Nutritional aspects of food extrusion: a review

Physicochemical, nutraceutical, and sensory evaluation of a milk-type plant-based beverage of extruded common bean (Phaseolus vulgaris L.) added with iron

Milk-type beverages are popular vegan products requiring iron and calcium fortification to improve their nutritional value, as iron deficiency is the world's most prevalent nutritional problem. This research aimed to develop and characterize an extruded common bean (Phaseolus vulgaris L.)-based milk-type beverage added with bean protein isolate and iron. The formulations included flavors (non-flavored, vanilla, and nut) and two iron concentrations (2 and 3 mg FeSO4/100 mL). Extrusion increased the beverages' protein (+17.38 %) and starch digestibility, and reduced their antinutritional compounds (trypsin inhibitors, condensed tannins, and carbonates). Developed beverages' formulations differed from a commercial soybean beverage in their physicochemical properties but were more nutritious (protein: 3.33-3.44 %; fiber: 3.43-4.08 %). Iron-added beverages displayed a medium sensory acceptance (best overall likeness: 5.3-6.2). The developed beverage is a suitable, sensory-accepted, and nutritious bean-based beverage, suggesting novel research lines improving vegan beverage formulations to increase average daily iron intake.

A comparative analysis of nutritional quality, amino acid profile, and nutritional supplementations in plant-based products and their animal-based counterparts in the UK

Plant-based (PB) food products have surged in popularity over the past decade. Available PB products in the UK market were extracted from NielsenIQ Brandbank and compared with animal-based (AB) counterparts in their nutrient contents and calculated Nutri-Scores. The amino acid contents of four beef products and their PB alternatives were analysed by LC-MS/MS. PB products consistently exhibited significantly higher fibre content across all food groups. Protein was significantly higher in AB products from all food groups except beef and ready meals. PB products were more likely to have higher Nutri-Scores compared to AB counterparts, albeit with greater score variability within each food group. Nutrient fortifications were primarily focused on dairy and ready meals; the most supplemented nutrient was vitamin B12 (found in 15% of all products). A higher proportion of EAAs in relation to total protein content was observed in all beef products.

Nutrition strategies to control post-weaning diarrhea of piglets: From the perspective of feeds

Post-weaning diarrhea (PWD) is a globally significant threat to the swine industry. Historically, antibiotics as well as high doses of zinc oxide and copper sulfate have been commonly used to control PWD. However, the development of bacterial resistance and environmental pollution have created an interest in alternative strategies. In recent years, the research surrounding these alternative strategies and the mechanisms of piglet diarrhea has been continually updated. Mechanically, diarrhea in piglets is a result of an imbalance in intestinal fluid and electrolyte absorption and secretion. In general, enterotoxigenic Escherichia coli (ETEC) and diarrheal viruses are known to cause an imbalance in the absorption and secretion of intestinal fluids and electrolytes in piglets, resulting in diarrhea when Cl- secretion-driven fluid secretion surpasses absorptive capacity. From a perspective of feedstuffs, factors that contribute to imbalances in fluid absorption and secretion in the intestines of weaned piglets include high levels of crude protein (CP), stimulation by certain antigenic proteins, high acid-binding capacity (ABC), and contamination with deoxynivalenol (DON) in the diet. In response, efforts to reduce CP levels in diets, select feedstuffs with lower ABC values, and process feedstuffs using physical, chemical, and biological approaches are important strategies for alleviating PWD in piglets. Additionally, the diet supplementation with additives such as vitamins and natural products can also play a role in reducing the diarrhea incidence in weaned piglets. Here, we examine the mechanisms of absorption and secretion of intestinal fluids and electrolytes in piglets, summarize nutritional strategies to control PWD in piglets from the perspective of feeds, and provide new insights towards future research directions.

Analysis of the Nutritional Composition of Ready-to-Use Meat Alternatives in Belgium

BACKGROUND

The interest in meat alternatives has increased over the years as people embrace more varied food choices because of different reasons. This study aims to analyse the nutritional composition of ready-to-use meat alternatives and compare them with meat (products).

METHODS

Nutritional composition values were collected in 2022 of all ready-to-use meat alternatives in Belgian supermarkets, as well as their animal-based counterparts. A one-sample t-test was performed to test the nutritional composition of ready-to-use meat alternatives against norm values, while an independent samples t-test was used to make the comparison with meat.

RESULTS

Minced meat and pieces/strips/cubes scored favourably on all norm values. Cheeseburgers/schnitzels, nut/seed burgers and sausages contained more than 10 g/100 g total fat. The saturated fat and salt content was lower than the norm value in each category. Legume burgers/falafel contained less than 10 g/100 g protein. Vegetarian/vegan minced meat and bacon contained fewer calories, total and saturated fat, and more fibre compared to their animal-based counterparts.

CONCLUSIONS

Minced meat and pieces/strips/cubes came out as the most favourable categories regarding nutritional composition norm values. Vegetarian/vegan steak came out the least favourable compared to steak, while vegetarian/vegan minced meat and vegetarian/vegan bacon came out the most favourable compared to their animal-based counterparts.

Plant-Based Meat Analogues in the Human Diet: What Are the Hazards?

Research regarding meat analogues is mostly based on formulation and process development. Information concerning their safety, shelf life, and long-term nutritional and health effects is limited. This article reviews the existing literature and analyzes potential hazards introduced or modified throughout the processing chain of plant-based meat analogues via extrusion processing, encompassing nutritional, microbiological, chemical, and allergen aspects. It was found that the nutritional value of plant-based raw materials and proteins extracted thereof increases along the processing chain. However, the nutritional value of plant-based meat analogues is lower than that of e.g., animal-based products. Consequently, higher quantities of these products might be needed to achieve a nutritional profile similar to e.g., meat. This could lead to an increased ingestion of undigestible proteins and dietary fiber. Although dietary fibers are known to have many positive health benefits, they present a hazard since their consumption at high concentrations might lead to gastrointestinal reactions. Even though there is plenty of ongoing research on this topic, it is still not clear how the sole absorption of metabolites derived from plant-based products compared with animal-based products ultimately affects human health. Allergens were identified as a hazard since plant-based proteins can induce an allergic reaction, are known to have cross-reactivities with other allergens and cannot be eliminated during the processing of meat analogues. Microbiological hazards, especially the occurrence of spore- and non-spore-forming bacteria, do not represent a particular case if requirements and regulations are met. Lastly, it was concluded that there are still many unknown variables and open questions regarding potential hazards possibly present in meat analogues, including processing-related compounds such as n-nitrosamines, acrylamide, and heterocyclic aromatic amino acids.

Enhancing the nutritional and bioactive benefits of faba bean flour by combining preprocessing and thermoplastic extrusion: A comprehensive study on digestion-resistant peptides

This research assessed how three preprocessing techniques [soaking (S), soaking and reconstitution (SR), and soaking and dehulling (SD)] impact the protein digestibility and bioactivity of faba bean flours when combined with thermoplastic extrusion. Samples were compared against a control (C) of extruded faba bean flour without preprocessing. Applying preprocessing techniques followed by extrusion diminished antinutrient levels while enhancing protein hydrolysis and in vitro bioactivity in higher extent compared to C. Specifically, SD combined with extrusion was the most effective, achieving an 80% rate of protein hydrolysis and uniquely promoting the release of gastric digestion-resistant proteins (50-70 kDa). It also resulted in the highest release of small peptides (<3kDa, 22.51%) and free amino acids (15.50%) during intestinal digestion. Moreover, while all preprocessing techniques increased antioxidant (ABTS radical-scavenging), antidiabetic, and anti-hypertensive activities, SD extruded flour displayed the highest levels of dipeptidyl peptidase inhibition (DPP-IVi, IC50=13.20 µg/mL), pancreatic α-amylase inhibition (IC50=8.59 mg/mL), and angiotensin I-converting enzyme inhibition (ACEi, IC50=1.71 mg protein/mL). As a result, it was selected for further peptide and in silico bioactive analysis. A total of 24 bioactive peptides were identified in intestinal digests from SD extruded flour, all with potential DPP-IVi and ACEi activities, and six were also predicted as antioxidant peptides. VIPAGYPVAIK and GLTETWNPNHPEL were highlighted as resistant bioactive peptides with the highest antidiabetic and antioxidant potential. Our findings demonstrated that combining preprocessing (particularly SD) and thermoplastic extrusion enhances protein digestibility in faba beans and promotes the release of beneficial bioactive peptides in the intestine.

Over 100 years of vitamin E: An overview from synthesis and formulation to application in animal nutrition

The groundbreaking discovery of vitamin E by Evans and Bishop in 1922 was an important milestone in vitamin research, inspiring further investigation into its crucial role in both human and animal nutrition. Supplementing vitamin E has been proved to enhance multiple key physiological systems such as the reproductive, circulatory, nervous and muscular systems. As the main antioxidant in the blood and on a cellular level, vitamin E maintains the integrity of both cellular and vascular membranes and thus modulates the immune system. This overview showcases important and innovative routes for synthesizing vitamin E on a commercial scale, provides cutting-edge insights into formulation concepts for successful product form development and emphasizes the importance and future of vitamin E in healthy and sustainable animal nutrition.

Effect of extrusion on the formation, structure and properties of yam starch-gallic acid complexes

This paper investigated the effects of twin-screw extrusion treatment on the formation, structure and properties of yam starch-gallic acid complexes. Yam starch and gallic acid were extruded. The microstructure, gelatinization characteristics, and rheological properties of the samples were determined. The microstructure of extruded yam starch-gallic acid complexes presented a rough granular morphology, low swelling, and high solubility. The X-ray diffraction analysis showed that the extruded yam starch-gallic acid complexes exhibited A + V-type crystalline structure. Fourier transform infrared spectroscopy results showed that the extrusion treatment could destroy the internal orderly structure of yam starch, and the addition of gallic acid could further reduce its molecular orderliness. Differential scanning calorimetry analysis showed a decrease in the enthalpy of gelatinization of the sample. Dynamic rheological analysis showed that the storage modulus and loss modulus of the extruded yam starch-gallic acid complexes were significantly reduced, exhibiting a weak gel system. The results of viscosity showed that extrusion synergistic gallic acid reduced the peak viscosity and setback value of starch. In addition, extrusion treatment had an inhibitory effect on the digestibility of yam starch, and enhanced the interaction of gallic acid with yam starch or hydrolytic enzymes. Therefore, extrusion synergistic gallic acid has improved the structure and properties of yam starch-related products, which can provide new directions and new ideas for the development of yam starch.

Optimization of the extrusion parameters for the production of lentil-quinoa extrudates enriched with pumpkin

This study aimed to develop a protein-fiber-rich extruded product based on yellow lentil, quinoa, and pumpkin flours. The final product quality is affected by formulation and extrusion parameters. Therefore, the effect of the pumpkin-flour ratio (A: 25-75%) and feed moisture content (C: 14-22%) besides barrel screw speed (B: 120-180 rpm) on the physical attributes of extrudates was investigated. Box-Behnken experimental design and stepwise-response surface method were used to analyze the effects of various process variables and ingredients on extrudates. The pumpkin-flour ratio had a significant positive correlation with bulk density (BD), water solubility index (WSI), and oil absorption index. Whereas the correlation between pumpkin-flour ratio with hardness, porosity, expansion ratio (ER), and water absorption index (WAI) was negative (P < 0.05). The feed moisture content positively affected the water activity (aw) and WAI and negatively affected the harness of samples (P < 0.05). The screw speed had a positive effect on ER, porosity, and WSI, whereas it negatively influenced the hardness, BD, and aw. By increasing the pumpkin-flour ratio, air cell size and wall thickness of samples had been decreased. The results showed that 44.2% pumpkin flour, 22% feed moisture, and 172.1 rpm screw speed gave an optimized product. There was no significant difference between predicted and experimental values (except for ER). The optimized snack was a good source of fiber (around 15%), protein (17.3%), and antioxidants (TPC = 15.28 mg GAE.g-1 and antiradical scavenging activity (DPPH) = 33.66%). The caloric value of the optimized snack was 362.6 cal.100g-1. The current formulation can be considered as the base of snack food or plant-based meat alternatives.

Effect of extrusion on the protein structure and digestibility of extruded soybean protein

BACKGROUND

Extrusion is the main method for the preparation of plant-based meat. Current studies have focused on the effect of different extrusion parameters on the texture and quality of plant-based meat, but there has been less research on their digestibility. This study determined the textural properties of extruded soybean protein (ESPro) for different extrusion parameters and the digestibility after in vitro simulated digestion experiments. The effect of extrusion on the structure and digestibility of ESPro and the relationship between them were elucidated.

RESULTS

The results demonstrated a significant improvement in the digestibility of ESPro through extrusion, with the highest values for cohesiveness, springiness, chewiness, fibrous degree, digestibility, and proportion of digested peptides with <1 kDa molecular weight at an extrusion temperature of 160 °C and a screw speed of 30 rpm (ESPro1). In addition, β-sheet content in the secondary structure of the ESPro showed a significant negative association with ESPro digestibility.

CONCLUSION

In this study, extrusion could improve the digestibility of ESPro by altering the protein structure. This advancement holds the potential for more effective applications in plant-based meats. © 2023 Society of Chemical Industry.

Effect of different screw speeds on the structure and properties of starch straws

To illustrate the action mechanism of screw speed on the performance of starch-based straws during the extrusion process, starch-based straws at different screw speeds were prepared using a twin-screw extruder and the structures and characteristics were compared. The results indicated that as screw speeds improved from 3 Hz to 13 Hz, the A chain of amylopectin increased from 25.47 % to 28.87 %, and the B3 chain decreased from 6.34 % to 3.47 %. The absorption peak of hydroxyl group shifted from 3296 cm-1 to 3280 cm-1. The relative crystallinity reduced from 13.49 % to 9.89 % and the gelatinization enthalpy decreased from 3.5 J/g to 0.2 J/g. The performance of starch straws did not increase linearly with increasing screw speeds. The starch straw produced at screw speed of 7 Hz had the largest amylose content, the highest gelatinization temperature, the minimum bending strength, and the lowest water absorption rate in hot water (80 °C). Screw speed had a remarkable impact on the mechanical strength, toughness and hydrophobicity of starch-based straws. This study revealed the mechanism of screw speed on the mechanical strength and water resistance of starch straws in the thermoplastic extrusion process and created the theoretical basis for the industrial production of starch-based straws.

B Vitamins in Legume Ingredients and Their Retention in High Moisture Extrusion

Legumes have been recognised as healthy and environmentally friendly protein sources. Knowledge about the vitamin B contents in legume ingredients and extrudates is scarce. In this study, we investigated thiamin, riboflavin, niacin, and folate in various faba bean, lupin, and pea ingredients. Further, the retention of B vitamins in high moisture extrusion was studied. Prior to liquid chromatographic determinations of thiamin, riboflavin, niacin, and folate, vitamins were extracted by acid hydrolysis (niacin), enzymatic treatment (folate), or their combination (thiamin and riboflavin). The contents (on a dry matter basis) varied greatly among different ingredients: the thiamin content was 0.2-14.2 µg/g; riboflavin, 0.3-5.9 µg/g; niacin, 8.8-35.5 µg/g, and folate, 45-1453 ng/g. Generally, the highest levels were in flours and protein concentrates, whereas low levels were observed in isolates. The retention of B vitamins was excellent in high moisture extrusion, except for folate in faba bean, where the folate contents were 42-67% lower in the extrudates than in the respective ingredient mixtures. In terms of both vitamin B contents and their retention, extrudates containing substantial amounts of flour or protein concentrate are promising plant-based sources of thiamin, riboflavin, niacin, and folate.

Feeding Value of Lupins, Field Peas, Faba Beans and Chickpeas for Poultry: An Overview

Grain legumes are fair sources of protein, amino acids and energy, and can be used as a replacement for soybean meal in poultry feed formulations as the soybean meal becomes short in supply and costly. However, a concern associated with the use of grain legumes in poultry feeding is the presence of antinutritional factors. The effective processing and utilisation of these grain legumes in poultry feeding are well documented. The current review focuses on four selected grain legumes (lupins [Lupinus albus and Lupinus angustifolius], field peas [Phaseolus vulgaris], faba beans [Vicia faba] and chickpeas [Cicer arietinum]) and their nutrient content, the presence of antinutritional factors, processing methods and feeding value, including updated data based on recent research findings.

Comparative structural, digestion and absorption characterization of three common extruded plant proteins

Extruded plant proteins, also known as textured vegetable proteins (TVPs), serve as vital components in plant-based meat analogue, yet their structural and nutritional characteristics remain elusive. In this study, we examined the impact of high-moisture (HM) and low-moisture (LM) extrusion on the structures, digestion and absorption of three types of plant proteins. Extrusion transformed plant proteins from spherical to fibrous forms, and formed larger aggregate particles. It also led to the disruption of original disulfide bonds and hydrophobic interactions within protein molecules, and the formation of new cross-links. Intriguingly, compared to native plant proteins, TVPs' α-helix/β-sheet values decreased from 0.68 to 0.69 to 0.56-0.65. Extrusion increased the proportion of peptides shorter than 1 kD in digesta of TVPs by 1.44-23.63%. In comparison to unextruded plant proteins, TVPs exhibited lower content of free amino acids in cell transport products. Our findings demonstrated that extrusion can modify protein secondary structure by diminishing the α-helix/β-sheet value, and impact protein tertiary structure by reducing disulfide bonds and hydrophobic interactions, promoting the digestion and absorption of plant proteins. These insights offer valuable scientific backing for the utilization of extruded plant-based proteins, bolstering their role in enhancing the palatability and nutritional profile of plant-based meat substitutes.

Plant-based meat substitute analysis using microextraction with deep eutectic solvent followed by LC-MS/MS to determine acrylamide, 5-hydroxymethylfurfural and furaneol

For the analysis of plant-based meat substitutes and the determination of Maillard reaction products such as acrylamide, 5-hydroxymethylfurfural and furaneol, a novel and effective procedure based on hydrophobic natural deep eutectic solvent and liquid chromatography coupled with tandem mass spectrometry was developed for the first time. The 49 compositions of the deep eutectic solvents were designed and screened to select the most suitable option. The terpenoids eugenol and thymol in a molar ratio of 2:1 were selected as precursors for solvent formation, allowing effective extraction of the target analytes. The developed procedure comprised two main steps: extraction - in which the analytes are isolated from the solid sample due to the salting-out effect and pre-concentrated in the deep eutectic solvent, and back-extraction - in which the analytes are re-extracted into the formic acid solution for subsequent mass spectrometric detection. As the density of the aqueous phases changed during the extraction and back-extraction steps, the phenomenon of inversion of the coalesced organic phase was observed, which simplified the withdrawing of the phases. The linear range was 1-50 ng/mL for acrylamide, 10-1000 ng/mL for 5-hydroxymethylfurfural and 200-1000 ng/mL for furaneol with coefficients of determination above 0.9952. The developed method was fully validated and found recoveries were in the range 83-120%, with CVs not exceeding 4.9%. The method was applied to real sample analysis of pea-based meat substitutes.

Effect of extrusion cooking on the chemical and nutritional properties of instant flours: a review

Satisfying the nutritional requirements of consumers has made food industries focus on the development of safe, innocuous, easy-to-prepare products with high nutritional quality through efficient processing technologies. Extrusion cooking has emerged as a prominent technology associated with the nutritional and functional attributes of food products. This review aims to establish a theoretical framework concerning the influence of extrusion parameters on the functional and nutritional properties of precooked or instant flours, both as end-products and ingredients. It highlights the pivotal role of process parameters within the extruder, including temperature, screw speed, and raw materials moisture content, among others, and elucidates their correlation with the modifications observed in the structural composition of these materials. Such modifications subsequently induce notable changes in the ultimate characteristics of the food product. Detailed insights into these transformations are provided within the subsequent sections, emphasizing their associations with critical phenomena such as nutrient availability, starch gelatinization, protein denaturation, enhanced in vitro digestibility, reduction in the content of antinutritional factors (ANFs), and the occurrence of Maillard reactions during specific processing stages. Drawing upon insights from available literature, it is concluded that these effects represent key attributes intertwined with the nutritional properties of the end-product during the production of instant flours.

Characterization of Second-Generation Snacks Manufactured from Andean Tubers and Tuberous Root Flours

Andean roots, such as zanahoria blanca, achira, papa China, camote, oca, and mashua, contain high amounts of dietary fiber, vitamins, minerals, and fructo-oligosaccharides. This study aimed to demonstrate the possibility of obtaining healthy second-generation (2G) snacks (products obtained from the immediate expansion of the mixture at the exit of the extruder die) using these roots as raw materials. Corn grits were mixed with Andean root flour in a proportion of 80:20, and a Brabender laboratory extruder was used to obtain the 2G snacks. The addition of root flour increased the water content, water activity, sectional expansion index, hygroscopicity, bulk density, and water absorption index but decreased the porosity. However, all 2G snacks manufactured with Andean root flour showed better characteristics than did the control (made with corn grits) in texture (softer in the first bite and pleasant crispness) and optical properties (more intense and saturated colors). The developed snacks could be considered functional foods due to the high amount of carotenoids and phenolic compounds they exhibit after the addition of Andean root flours. The composition of raw roots, specifically the starch, fiber, and protein content, had the most impact on snack properties due to their gelatinization or denaturalization.

Characterization of the mechanical properties of high-moisture meat analogues using low-intensity ultrasound: Linking mechanical properties to textural and nutritional quality attributes

Plant-based meat analogues offer possible alternatives to meat consumption. However, many challenges remain to produce a palatable meat analogue as well as to understand the roles of different processing steps and ingredients on both the texture and nutritional properties of the final product. The goal of this paper is to help with addressing these challenges by using a low-intensity ultrasonic transmission technique, both online and 24 h after production, to investigate high-moisture meat analogues made from a blend of soy and wheat proteins. To understand the ultrasonic data in the context of traditional characterization methods, physical properties (meat analogue thickness, density, peak cutting force) and protein nutritional quality attributes of the meat analogues were also characterized separately. The ultrasonic velocity was found to decrease with the feed moisture content and to be strongly correlated (r = 0.97) with peak cutting force. This strong correlation extends over a wide range of moisture contents from 58% to 70%, with the velocity decreasing from about 1730 m/s to 1660 m/s over this range. The protein quality was high for all moistures, with the highest amino acid score and in vitro protein digestibility being observed for the highest moisture content treatment. The accuracy of the ultrasonic measurements was enhanced by the development of an innovative non-contact method, suitable for materials exhibiting low ultrasonic attenuation, to measure the meat analogue thickness ultrasonically and in a sanitary fashion - an advance that is potentially useful for online monitoring of production problems (e.g., extruder barrel-fill and cooling-die temperature issues). This study demonstrates, for the first time, the feasibility of using ultrasonic transmission techniques to measure both velocity and sample thickness simultaneously and provide information in real time during production that is well correlated with some textural and nutritional attributes of meat analogues.

Effect of wheat dextrin on corn flour extrusion characteristics

Wheat dextrin is a modified wheat starch, classified as water-soluble. This study investigated the effect of wheat dextrin as an ingredient in corn flour blends on extrusion characteristics. Blends were prepared at 0, 10 and 20 % fibre content. DOE was used to design experiments and investigate the effects of variables selected to be studied. Feed moisture content was set at 18-25 %, temperature at 110-150 °C and specific feeding load at 0.100-0.150kg/rev. Moisture content, water absorption and solubility indices, color, sectional expansion index, density, hardness, crispiness (work (Wc) and number of spatial ruptures (Nsr)) and specific mechanical energy were evaluated. A regression model was established using response surface methodology, and processing conditions for optimal quality were generated (e.g., WSI: 96.9 %, SME: 96.9 %, final MC: 93.9 %). Wheat dextrin solubility characteristics for moisture content, WAI and WSI were inconclusive, showing a high tendency to insoluble behavior. For expansion, lightness and SME characteristics depended on processing conditions, especially temperature. Crispness was highest at low MC (18.87 %) x high fiber content (20 %) (e.g., Nsr: 1.2-1.5/mm), whereas values were the lowest at high MC (25.70 %) x low fiber content (0 %) (e.g., Nsr: 0.5-0.7/mm). Optimal conditions were set at 12 % fiber content, 19 % feed moisture content, 130 °C and a specific feeding load of 0.146 kg/rev. This study showed that it is impossible to classify wheat dextrin as acting strictly according to soluble fiber characteristics based on extrudate characteristics.

Use of K2CO3 to Obtain Products from Starch-Oil Mixtures by Extrusion

Mixtures of potato starch with oils (rapeseed and sunflower) were extruded. To improve the complexation of edible oils, a catalyst was added in amounts of 3 g, 6 g, and 9 g per 100 g of sample. The aim was to obtain potato starch extrudates with a high degree of complexation and edible oils during physical modification (extrusion) with the innovative use of K2CO3 as a catalyst. Selected functional properties (water solubility index and fat absorption index) and technological properties of the obtained extrudates (radial expansion index); color in the L*, a*, and b* systems, and the specific surface area was determined from the water vapor adsorption isotherm (SBET). The fat content was determined as external, internal, or bound, and complexed by amylose to assess the degree and manner of fat complexation during extrusion. Iodine-binding capacity and the complexing index were determined to confirm the formation of amylose-lipid complexes. The incorporation of edible oils resulted in a decrease in the radial expansion index and water solubility index compared to control samples. The extrudates were dark orange. Extrudates obtained at the temperature profile L: 80/80/80/60/60/50 °C, depending on the cooking oil, complexed from 48-79% of the introduced rapeseed oil and from 36-40% of the sunflower oil. The extrusion temperature profile (H: 100/100/100/75/75/60 °C) reduced the amount of bound lipid fractions. Using potassium carbonate in the extrusion of starch-lipid systems gives hope for further increasing the share of lipids in extruded mixtures.

Fish processing side streams are promising ingredients in diets for rainbow trout (Oncorhynchus mykiss) - Effects on growth physiology, appetite, and intestinal health

Due to the growth of aquaculture and the finite supply of fishmeal and oil, alternative marine protein and lipid sources are highly sought after. Particularly promising is the use of side streams from the fish processing industry, allowing for the recovery and retention of otherwise lost nutrients in the food production chain. The aim of the present study was to evaluate the potential of three fish processing side streams as fish feed ingredients. The side streams originated from different stages of the production chain, were used without further processing, and included sprat trimmings (heads, frames, viscera), marinated herring (fillets) and mackerel in tomato sauce (fillets and sauce). The three side streams contained moderate levels of protein (28-32% dry matter) and high levels of lipid (34-43%). The sprat trimmings included ca. 29% ash and 1.5% phosphorous which may add value due to the high level of essential minerals but needs to be considered in feed formulations. Three diets were formulated to include 50% of each side stream replacing all fishmeal and ca. 80% of the fish oil of the control diet, which contained 35% fishmeal and 10% fish oil. The diets were evaluated in a 12-week feeding trial using rainbow trout (Oncorhynchus mykiss). Fish fed the sprat diet displayed the highest feed intake and growth, and showed no negative effects on the intestinal health. The mackerel side stream displayed a good digestibility but resulted in lower growth rates compared to the sprat trimmings. Fish fed the herring diet, displayed the lowest performance regarding growth, feed intake and digestibility. They further exhibited a reduction in nutrient uptake in both proximal and distal intestine, likely contributing to the observed lower digestibility and growth, and a reduction in plasma ghrelin levels. As part of a circular approach to increase marine lipid and protein production for fish feed, the tested sprat and mackerel side streams are promising raw materials however additional studies using more commercial-like feed formulations are encouraged.

Comprehensive improvement of nutrients and volatile compounds of black/purple rice by extrusion-puffing technology

Introduction

Black/purple rice is a pigmented rice variety that contains high levels of anthocyanins, flavonoids, and other valuable bioactive compounds. Owing to its robust anti-inflammatory and antioxidant properties, black/purple rice exerts a beneficial effect on human health. Extrusion puffing technology has emerged as a promising means of improving rice flavor with lesser effect on nutrient content. In this study, metabolomics approach was used to conduct comprehensive metabolomics analyses aimed at examining the impact of extrusion puffing on black/purple rice nutritional value and flavor.

Methods

Firstly, the basic nutrient composition contents and extrudate characteristics of black/purple rice and Extrusion puffed black/purple rice were conducted. Then metabolomics profiling analyses of black/purple rice samples were performed to explore the impact of the extrusion puffing process on nutrient content and bioactive properties, in which we quantitatively determined the flavonoids and evaluated relative contents of volatile compounds.

Results

These analyses revealed that following extrusion puffing, black/purple rice exhibited significant improvements in the content of nutrients including flavonoids, minerals, and proteins together. Extrusion puffing additionally increased the diversity of volatile compounds within black/purple rice.

Discussion

These results suggest that extrusion puffing represents an effective means of substantially improving the functional and nutritional properties of black/purple rice, offering beneficial effects on consumer health. Overall, these data provide novel insights into the quality of extrusion puffed black/purple rice that will guide future efforts to establish how extrusion puffing can alter the nutrient content in a range of foods, thereby supporting the further development of a range of healthy food products.

Relationship between Physicochemical, Techno-Functional and Health-Promoting Properties of Fiber-Rich Fruit and Vegetable By-Products and Their Enhancement by Emerging Technologies

The preparation and processing of fruits and vegetables produce high amounts of underutilized fractions, such as pomace and peel, which present a risk to the environment but constitute a valuable source of dietary fiber (DF) and bioactive compounds. The utilization of these fiber-rich products as functional food ingredients demands the application of treatments to improve their techno-functional properties, such as oil and water binding, and health-related properties, such as fermentability, adsorption, and retardation capacities of glucose, cholesterol, and bile acids. The enhancement of health-promoting properties is strongly connected with certain structural and techno-functional characteristics, such as the soluble DF content, presence of hydrophobic groups, and viscosity. Novel physical, environmentally friendly technologies, such as ultrasound (US), high-pressure processing (HPP), extrusion, and microwave, have been found to have higher potential than chemical and comminution techniques in causing desirable structural alterations of the DF network that lead to the improvement of techno-functionality and health promotion. The application of enzymes was related to higher soluble DF content, which might be associated with improved DF properties. Combined physical and enzymatic treatments can aid solubilization and modifications, but their benefit needs to be evaluated for each DF source and the desired outcome.

Optimization of rheological characteristics of bread dough supplemented with defatted wheat germ

Optimization of bread dough formulation with defatted wheat germ (DWG) in terms of dough rheological properties was the objective of this study. Fractional factorial design 2 V 5 - 1 was applied in order to investigate influence of DWG granulation (<150 µm and 150-1000 µm), DWG content (10 and 20%), addition of gluten (0 and 5%), ascorbic acid (0.004 and 0.008%) and combined improver (0.1 and 0.3%) on farinograph and extensograph parameters. Responsive variables were water absorption and the degree of softening, obtained by farinograph, and resistance to extension and extensibility as well as their ratio, obtained by extensograph analysis. Gluten addition expressed dominant positive effect on water absorption and the degree of softening. The most pronounced negative effect on dough resistance exhibited DWG content (contribution of 57%). The combination of DWG with smaller particle size and 5% of gluten addition increased both resistance and extensibility, but R/E ratio was not affected. The optimal values for DWG granulation, DWG content, gluten content, ascorbic acid content and combined improver content were: < 150 µm, 14.24%, 4.83%, 0.004% and 0.1%, respectively, while predicted values for desired responsible variables were: water absorption 65.90%, degree of softening 84.05 FU, resistance 301.30 EU, extensibility 108.55 mm and R/E 2.5.

Three-Dimensional Printing of Foods: A Critical Review of the Present State in Healthcare Applications, and Potential Risks and Benefits

Three-dimensional printing is one of the most precise manufacturing technologies with a wide variety of applications. Three-dimensional food printing offers potential benefits for food production in terms of modifying texture, personalized nutrition, and adaptation to specific consumers' needs, among others. It could enable innovative and complex foods to be presented attractively, create uniquely textured foods tailored to patients with dysphagia, and support sustainability by reducing waste, utilizing by-products, and incorporating eco-friendly ingredients. Notable applications to date include, but are not limited to, printing novel shapes and complex geometries from candy, chocolate, or pasta, and bio-printed meats. The main challenges of 3D printing include nutritional quality and manufacturing issues. Currently, little research has explored the impact of 3D food printing on nutrient density, bioaccessibility/bioavailability, and the impact of matrix integrity loss on diet quality. The technology also faces challenges such as consumer acceptability, food safety and regulatory concerns. Possible adverse health effects due to overconsumption or the ultra-processed nature of 3D printed foods are major potential pitfalls. This review describes the state-of-the-art of 3D food printing technology from a nutritional perspective, highlighting potential applications and current limitations of this technology, and discusses the potential nutritional risks and benefits of 3D food printing.

Protein blends and extrusion processing to improve the nutritional quality of plant proteins

Plant proteins have low protein nutritional quality due to their unbalanced indispensable amino acid (IAA) profile and the presence of antinutritional factors (ANFs) that limit protein digestibility. The blending of pulses with cereals/pseudocereals can ensure a complete protein source of IAA. In addition, extrusion may be an effective way to reduce ANFs and improve protein digestibility. Thereby, we aimed to improve the protein nutritional quality of plant protein ingredients by blending different protein sources and applying extrusion processing. Protein blends were prepared with pea, faba bean, quinoa, hemp, and/or oat concentrates or flours, and extrudates were prepared either rich in pulses (texturized vegetable proteins, TVPs) or rich in cereals (referred to here as Snacks). After extrusion, all samples showed a reduction in trypsin inhibitor activity (TIA) greater than 71%. Extrusion caused an increase in the total in vitro protein digestibility (IVPD) of TVPs, whereas no significant effect was shown for the snacks. According to the molecular weight distribution, TVPs presented protein aggregation. The results suggest that the positive effect of decreased TIA on IVPD is partially counteracted by the formation of aggregates during extrusion which restricts enzyme accessibility. After extrusion, all snacks retained a balanced amino acid score whereas a small loss of methionine + cysteine was observed in the TVPs, resulting in a small reduction in IAA content. Thus, extrusion has the potential to improve the nutritional quality of TVPs by reducing TIA and increasing protein digestibility.

Extrusion as a tool to enhance the nutritional and bioactive potential of cereal and legume by-products

Cereal and legume by-products obtained from primary food production industries pose an environmental and economic problem. Nevertheless, these residues can potentially yield value-added products due to their elevated content of dietary fiber, phytochemicals, vitamins, minerals, and residual levels of proteins, which makes them a suitable and heightened option for reutilization in human consumption. Several studies identify extrusion as an innovative technology to modify the technofunctionality and nutritional properties of cereal and legume by-products, resulting in the production of improved ingredients. This review focuses on studies that evaluate the effect of extrusion to improve the nutritional and bioactive potential of cereal and legume by-products. A revision of the extrusion process parameters that improve the profile and bioavailability of dietary fiber, proteins, and phenolic compounds, and minimize antinutritional factors associated to cereal and legume by-products was done. The composition of by-products and process parameters such as feed moisture, barrel temperature and screw speed influence the resulting effect of extrusion. Studies suggest that extruding composite feedstock containing cereal or legume by-products may limit the molecular modifications that trigger the nutritional improvements. Therefore, extrusion applied as a pretreatment represents an interesting and economic alternative to improve the profile and bioavailability of the nutrients found in cereal and legume by-products which might lead to the development of functional ingredients useful to produce foods aimed to prevent chronic diseases.

Soybean residue (okara) modified by extrusion with different moisture contents: Physical, chemical, and techno-functional properties

To increase hydration properties and soluble fiber content, okara with different moisture contents (30, 35, and 40%) was extruded in single-screw equipment, keeping the temperature (120 °C) and screw speed (115 rpm) fixed. The physical, chemical, and techno-functional properties of extruded and non-extruded okara (control) were evaluated. The microstructure, color, chemical composition, and techno-functional properties of okara were altered after extrusion. The extruded samples showed general microstructure aspects similar between them, with an irregular and rough surface, striated parts, orifices, and some agglomerated particles with distorted, compact, and amorphous appearance, different from control. Among the modified samples, okara extruded with 30% moisture showed more intense changes in relation to the samples extruded with 35 and 40% moisture. Based on the results, it can be inferred that okara extruded with 35% moisture is the most suitable. Under this condition, there was an increase of 80% in soluble fiber content, 45% in water absorption and holding capacity and 11% in solid stability in water, the maintenance of swelling and oil absorption and holding capacities and the reduction of protein solubility in water. X-ray diffraction analysis showed that crystalline phase was affected by extrusion.

The effect of psyllium fiber on the in vitro starch digestion of steamed and roasted wheat based dough

This study aimed to determine how the addition of psyllium fiber to steamed and roasted wheat-based flat dough pieces affected the in vitro starch digestibility. Wheat flour was replaced with 10% psyllium fiber in the preparation of fiber-enriched dough samples. Two distinct methods of heating were utilised: steaming (100 °C, 2 min & 10 min) and roasting (100 °C, 2 min & 250 °C, 2 min). Rapidly digestible starch (RDS) fractions reduced significantly in both steamed and roasted samples, whereas slowly digestible starch (SDS) fractions increased significantly only in samples roasted at 100 °C and steamed for 2 min. The roasted samples had a lower RDS fraction than the steamed samples only when fiber was added. This study demonstrated the effect of processing method, duration, temperature, formed structure, matrix and the addition of psyllium fiber on in vitro starch digestion by altering starch gelatinization, gluten network, and consequently enzyme access to substrates.

Modification mechanism of protein in rice adjuncts upon extrusion and its effects on nitrogen conversion during mashing

The traditional production of wort with adjunct-introduced was achieved by double mashing procedure, which hindered the utilization of proteins in adjunct and led to a deficiency of nitrogen in wort. In this study, the modification mechanism of the extrusion pretreatment on the structure characterization of rice flour protein was investigated. The decoction mashing procedure was performed to enhance the nitrogen conversion of the extruded rice adjunct. Decreased solubility along with disrupted secondary and tertiary structures of rice protein were observed after extrusion. As a result, the total nitrogen, free amino nitrogen, and free amino acids content of wort with extruded rice adjunct-introduced were improved by 23.28 %, 34.67 %, and 7.33 %, respectively, which could be verified by the electrophoretic patterns of the wort protein. The application of extrusion as a pretreatment of adjuncts can promote the protein availability of adjuncts in the decoction mashing stage.

Effects of different rapid cooling temperatures and annealing on functional properties of starch straws after thermoplastic extrusion

To improve the performance of starch straws in rapidly cooling and annealing procedure of thermoplastic extrusion, control straw was prepared through slowly cooling at 25 °C, and starch straw was prepared through regulating different rapid cooling temperatures including 20 °C, 5 °C, -10 °C and -20 °C. The results indicated that control straw exhibited a homogeneous state, while starch straws treated by rapid cooling displayed like a wash-board structure. Compared to control straw, the ratio of the absorption peak intensity of 1047 and 1022 cm^-1 increased from 1.050 to 1.455 as cooling temperatures decreased from 25 °C to -20 °C, indicating short-range order of the double helix structure significantly enhanced. The relative crystallinities of starch straws increased from 12.01 % to 16.58 %. The maximum bending force value (60.92 N) of starch straws cooled at -20 °C was significantly higher than that (46.14 N) of control straw. Conversely, the modulus of elasticity in bending values (4.21-16.43 N/cm) of rapid cooling-treated straws were significantly lower than that (48.42 N/cm) of control straw. Water absorption of rapid cooling-treated straws were lower than that of control straw, indicating the hydrophobicity property of starch straws significantly improved.

Breadfruit (Artocarpus altilis): Processing, nutritional quality, and food applications

Breadfruit is an underutilized but highly nutritive crop containing complex carbohydrates while being low in fat. It is also a good source of essential amino acids (leucine, isoleucine, and valine). With a better understanding of breadfruit’s morphology, its potential as a global solution to food security has been gaining popularity. Breadfruit has been forecasted to have a larger amount of suitable cultivable land area compared to major crops such as rice and wheat, making its cultivation more desirable. Due to its highly perishable nature, good post-harvesting and post-processing practices are essential to extend the shelf life of breadfruit for global transportation and consumption. This paper aims to provide a comprehensive review on various processing methods of flour and starch, nutritional significance and new food applications of this novel food staple. In this review, the effects of the different processing and post-processing methods of breadfruit flour and starch have been described, and the nutritional composition and application of breadfruit flour as an ingredient replacer in various food applications have been discussed. It is vital to understand the processing and post-processing methods of breadfruit flour to enhance its shelf-life, physicochemical and functional properties. Furthermore, a compilation of novel food applications has been done to promote its use in the food industry. In conclusion, breadfruit flour and starch are highly versatile for use in numerous food products with added health benefits.

Conformational changes and physicochemical attributes of texturized pea protein isolate-konjac gum: With a new perspective of residence time during extrusion

The present study aimed to investigate the effects of different extrusion temperatures (110, 130 and 150 °C) and konjac gum addition (0.1 %, 0.2 %, and 0.3 %) on the flow behavior, physicochemical properties and microstructure of extruded pea protein isolate (PPI). The results showed that the textured protein could be improved by enhancing the extrusion temperature and adding konjac gum during extrusion. The water/oil holding capacity of PPI decreased and the SH content increased after extrusion. With temperature and konjac gum content increased, the β-sheet of extruded proteins transformed to other secondary structural components, and Trp residue transformed to a more polar environment, illustrating the changes in protein conformation. All extruded samples presented as yellow hue with little green and higher lightness, while excessive extrusion process reduced the brightness and promoted more formation of browning pigments. Extruded protein showed more associated layered with some air pores, and its hardness and chewiness increased with the increase of temperature and konjac gum concentration. Cluster analysis showed that the addition of konjac gum could effectively improve the quality characteristics of pea protein under low temperature extrusion, and the effect was similar to that of high temperature extrusion product. With the increase of konjac gum concentration, the flow pattern of protein extrusion gradually converted from plug flow to mixing flow, and the disorder degree of polysaccharide protein mixing system was enhanced. Moreover, Yeh-jaw model showed better fitting effect in F(θ) curves compared to Wolf-white.

Physical, Chemical and Functional Attributes of Neera Honey Infused Extrudates

Owing to the demand for the consumption of healthy extrudates, this study explored the infusion of neera (coconut inflorescence sap) honey in rice flour, corn flour and coconut milk residue blend-based extrudates. Neera honey, the concentrated coconut inflorescence sap, has numerous nutrients and a natural source of essential vitamins. Hence, the potential of neera honey as a biofortifying compound for the production of healthy extrudates was investigated. The rice and corn based extrudates supplemented with different concentration of neera honey have been prepared until the mix reaches 16 and 20% (w.b.) of feed moisture. Effect of addition of neera honey on the physical properties (expansion ratio, bulk density, specific length), functional properties (water absorption, water solubility, oil absorption), biochemical properties (total carbohydrates, total sugar, reducing sugar, phenolics, flavonoids, antioxidants), color parameters(L*, a*, b*), proximate compositions (moisture content, ash, protein, fat) and mineral profile of extrudates were recorded. Results suggest that addition of neera honey had a significant (p ˂ 0.05) impact on all the physico-chemical parameters evaluated. Incorporation of neera honey (feed moisture -20%) resulted in extrudates with less expansion, high bulk density and specific length, having high sugar, protein, phenolics, vitamin C and antioxidant activity. The combination of 60% rice flour + 25% corn flour +15% coconut milk residue samples infused with neera honey upto 16% feed moisture was found suitable for the preparation of nutritious extrudates based on functional characterization and minerals evaluation.

Effects of Adding Blueberry Residue Powder and Extrusion Processing on Nutritional Components, Antioxidant Activity and Volatile Organic Compounds of Indica Rice Flour

Using indica rice flour as the main raw material and adding blueberry residue powder, the indica rice expanded powder (REP) containing blueberry residue was prepared by extrusion and comminution. The effects of extrusion processing on the nutritional components, color difference, antioxidant performance and volatile organic compounds (VOCs) of indica rice expanded powder with or without blueberry residue were compared. The results showed that the contents of fat and total starch decreased significantly after extrusion, while the contents of total dietary fiber increased relatively. Especially, the effect of DPPH and ABTS+ free radical scavenging of the indica rice expanded flour was significantly improved by adding blueberry residue powder. A total of 104 volatile compounds were detected in the indica rice expanded powder with blueberry residue (REPBR) by Electronic Nose and GC-IMS analysis. Meanwhile, 86 volatile organic compounds were successfully identified. In addition, the contents of 16 aldehydes, 17 esters, 10 ketones and 8 alcohols increased significantly. Therefore, adding blueberry residue powder to indica rice flour for extrusion is an efficient and innovative processing method, which can significantly improve its nutritional value, antioxidant performance and flavor substances.

Legume Protein Extracts: The Relevance of Physical Processing in the Context of Structural, Techno-Functional and Nutritional Aspects of Food Development

Legumes are sustainable protein-rich crops with numerous industrial food applications, which give them the potential of a functional food ingredient. Legume proteins have appreciable techno-functional properties (e.g., emulsification, foaming, water absorption), which could be affected along with its digestibility during processing. Extraction and isolation of legumes’ protein content makes their use more efficient; however, exposure to the conditions of further use (such as temperature and pressure) results in, and significantly increases, changes in the structural, and therefore functional and nutritional, properties. The present review focuses on the quality of legume protein concentrates and their changes under the influence of different physical processing treatments and highlights the effect of processing techniques on the structural, functional, and some of the nutritional, properties of legume proteins.

Nutritional and bioactive components of rice-chickpea based snacks as affected by severe and mild extrusion cooking

BACKGROUND

Severe extrusion cooking (SEC) has been extensively explored for product development and has been compared with mild extrusion cooking (MEC). Different blends of chickpea-rice flour for extrusion can be used to achieve a balance between nutritive value and valued product characteristics. This study was therefore designed to optimize the severe and mild extrusion conditions for rice-chickpea flour blends to cater for increasing consumer demand for snacks with the aim of comparing the effects of severe and mild extrusion cooking (MEC) on nutritional quality.

RESULTS

The results revealed a significantly (P < 0.05) higher percentage reduction in sucrose during severe extrusion (46.85%) compared to mild extrusion (7.88%). Likewise, the percentage increase in maltose, glucose, and fructose was significantly (P < 0.05) higher during SEC than during mild extrusion. Total phenolic content increased by 13.96% during mild extrusion, whereas, during severe extrusion it decreased by 15%. Total flavonoid content and total antioxidant activity decreased by 11.11% and 15.63%, respectively, during severe extrusion whereas, total flavonoid content and total antioxidant activity increased by 13.17% and 24.29%, respectively, during MEC. The loss in condensed tannin content was significantly (P < 0.05) higher (33.82%) during SEC than with MEC (12.05%). With regard to amino acids, the maximum loss was observed in methionine (53.38%) followed by lysine (40.63%) during SEC. However, the mineral content was found to increase during SEC.

CONCLUSION

This study revealed that MEC is superior to SEC in terms of minimizing deleterious effects on overall nutritional value of ready-to-eat snacks. © 2022 Society of Chemical Industry.

Effect of the Production Parameters and In Vitro Digestion on the Content of Polyphenolic Compounds, Phenolic Acids, and Antiradical Properties of Innovative Snacks Enriched with Wild Garlic (Allium ursinum L.) Leaves

A new type of corn snack has been created containing additions of wild garlic (Allium ursinum L.). This medicinal and dietary plant has a long tradition of use in folk medicine. However, studies on wild garlic composition and activity are fairly recent and scarce. This research aimed to investigate the influence of the screw speed and A. ursinum amounts on the antiradical properties as well as the content of polyphenolic compounds and individual phenolic acids of innovative snacks enriched with wild garlic leaves. The highest radical scavenging activity and content of polyphenols and phenolic acids were found in the snacks enriched with 4% wild garlic produced using screw speed 120 rpm. The obtained findings demonstrated that snacks enriched with wild garlic are a rich source of polyphenolic compounds. Since the concentration of such compounds is affected by many factors, e.g., plant material, presence of other compounds, and digestion, the second aim of this study was to determine radical scavenging activity, the content of polyphenols, and individual phenolic acids of snacks after in vitro simulated gastrointestinal digestion. Using an in vitro two-stage model, authors noted a significant difference between the concentration of polyphenolic compounds and the polyphenol content of the plant material before digestion.

Bioactive, Mineral and Antioxidative Properties of Gluten-Free Chicory Supplemented Snack: Impact of Processing Conditions

This study aimed to investigate the impact of chicory root addition (20-40%) and extrusion conditions (moisture content from 16.3 to 22.5%, and screw speed from 500 to 900 rpm) on bioactive compounds content (inulin, sesquiterpene lactones, and polyphenols) of gluten-free rice snacks. Chicory root is considered a potential carrier of food bioactives, while extrusion may produce a wide range of functional snack products. The mineral profiles were determined in all of the obtained extrudates in terms of Na, K, Ca, Mg, Fe, Mn, Zn, and Cu contents, while antioxidative activity was established through reducing capacity, DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) tests. Chicory root addition contributed to the improvement of bioactive compounds and mineral contents, as well as antioxidative activities in all of the investigated extrudates in comparison to the pure-rice control sample. An increase in moisture content raised sesquiterpene lactones and minerals, while high screw speeds positively affected polyphenols content. The achieved results showed the important impact of the extrusion conditions on the investigated parameters and promoted chicory root as an attractive food ingredient in gluten-free snack products with high bioactive value.

Combined Thermomechanical-Biological Treatment for Corn By-Product Valorization into Added-Value Food (Feed) Material

The aim of this study was to apply the combined thermomechanical-biological treatment for corn processing by-product (CPBP) valorization to added-value food and feed material. The mechanical-thermal pre-treatment was performed by applying the extrusion technique. Extruded CPBPs (14, 16, and 18% moisture) were further biodegraded with Lactiplantibacillus plantarum-LUHS122 (Lpl), Liquorilactobacillus uvarum-LUHS245 (Lu), Lacticaseibacillus casei-LUHS210 (Lc), and Lacticaseibacillus paracasei-LUHS244 (Lpa). Acidity parameters, microbial characteristics, sugars concentration, amino and fatty acids profile, biogenic amines (BA), and antibacterial and antifungal properties of CPBP were analyzed. Fermented CPBP had a reduced count of mould/yeast. A significantly lower (p ≤ 0.05) count of total enterobacteria was found in most of the extruded-fermented CPBP. Fermentation of extruded CPBP (moisture of 16 and 18%) increased valine and methionine content. Cadaverine and spermidine were not found after treatment of CPBP, and the lowest content of BA was found in the extruded-fermented (Lpa, moisture 18%) CPBP. Applied treatment had a significant effect on most of the fatty acids. CPBP fermented with Lpl, Lu, and Lpa displayed inhibition properties against 3 of the 10 tested pathogenic/opportunistic bacterial strains. Extruded-fermented (Lu, Lc, and Lpa moisture of 14 and 18%) CPBP showed antifungal activity against Rhizopus. Extruded-fermented (14% moisture, Lpl) CPBP inhibited Rhizopus and Aspergillus fumigatus. In conclusion, combined treatment can improve certain parameters and properties of CPBP in order to produce safer and more nutritious ingredients for food and feed industries.

Twin-Screw Extrusion as Hydrothermal Technology for the Development of Gluten-Free Teff Flours: Effect on Antioxidant, Glycaemic Index and Techno-Functional Properties

Gluten-free products (GFP) currently are the fastest-growing category of baked goods probably due to the high worldwide incidence of celiac disease (CD). Refined rice is one of the most used cereal flour for GFP development, due to its high content in starch and good technological aptitude. However, its low content in fibre, protein and minerals has awakened a recent interest as alternative to balance the GF flour formulas. Teff is a cereal with high levels in fibre and antioxidants compounds but the lack of gluten results in very limited techno-functional properties. Extrusion is a thermal technology that allows to combine flours, overcoming negative impacts on quality characteristics. This study evaluated the effect of twin-screw extruder on rice-teff (white and brown) mixtures with different teff concentrations (25, 50 and 75%) on their antioxidant, glycaemic index and techno-functional properties. The results showed than the high shear−temperature process produced important modifications on the flour, which were confirmed using scanning electron microscopy (SEM). Significant increases in total dietary fibre (16 to 100% increase) were observed in teff containing flours, due to carbohydrate−lipid−protein complexes, which lead to resistant starch, with no significant increase in rice flour. Hydration and pasting properties were significantly (p > 0.05) affected by extrusion, and the effect was related to the concentration of teff used. The thermal process showed a decrease in total phenol (TP) content for rice; however, extrusion enhanced the release of total phenol in rice-teff blends, which was reflected on the antioxidant activities of blend flours, especially those prepared with brown teff.

Effect of preconditioner conditions and soybean meal substitution with sunflower meal on the chemical composition of the commercial freshwater fish extrudates.. [DOI: 10.21203/rs.3.rs-2121700/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

The aim of the present study was to evaluate the combined effect of the preconditioner conditions and substitution soybean meal protein with sunflower meal protein on the chemical composition of freshwater fish feeds. This experiment was conducted using Box-Behnken design with three independent variables; i) substitution of soybean meal with sunflower meal at three levels 0, 25 and 50%, ii) preconditioner temperature at three levels of 85, 95 and 105 °C, iii) preconditioner moisture (15,17.5 and 20%). There was no significant effect of manipulating the level of the three independent variables on the extrudates crude protein, crude fat, ash level and trypsin inhibitor activity. Increasing the substitution of soybean meal by sunflower meal significantly increased the extrudates dry matter and crud fiber levels. Increasing the preconditioner temperature had no negative effects on all the essential amino acids levels with exception of the threonine level, while significant increase in arginine, histidine and alanine levels of the extrudates were observed. Increasing sunflower meal inclusion had a negative significant effect on lysine and tyrosine levels and had a significant positive effect on methionine and glycine levels. These results indicate that increasing of the preconditioner temperature has a positive effect on increasing the inclusion level of sunflower meal in freshwater fish diets.