Utilization of Plant Dietary Fibers to Reinforce Low-Calorie Dairy Dessert Structure

Potential of Nanocellulose as a Dietary Fiber Isolated from Brewer's Spent Grain

Steady growth in beer production is increasing the number of by-products named brewers' spent grain. Such by-products are a source of several components, where cellulose is usually present in high amounts. The aim of this study was to develop a protocol to obtain a mix of cellulose microfibers with an average diameter of 8-12 µm and cellulose nanoplatelets with an average thickness of 100 nm, which has several applications in the food industry. The process comprised one alkaline treatment followed by acid hydrolysis, giving a new mix of micro and nanocellulose. This mix was characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, and laser scanning microscopy corroborating the presence and measurements of the cellulose nanostructure, showing an aspect ratio of up to 500. Finally, we demonstrated that the administration of this new type of nanocellulose allowed us to control the weight of mice (feed intake), showing a significant percentage of weight reduction (4.96%) after 15 days compared with their initial weight, indicating the possibility of using this material as a dietary fiber.

Incorporating an upcycled orange fibre on flan formulation: Impact on sensory properties

Fruit by-products are a valuable source of ingredients, in the formulation of what is known by "upcycled foods". Orange pomace, a by-product of orange juice industry, is a dietary fibre source. In this work, a powdered ingredient with soluble fibre obtained from orange pomace was used as replacement of inulin in the formulation of source of fibre "flan" like puddings. Four different formulations were analysed using Flash Profile and instrumental texture: 100% inulin, 70% inulin: 30% orange fibre, 30% inulin: 70% orange fibre, 100% orange fibre. The replacement of 30% of pudding's total fibre with the new ingredient helped to improve the texture and general appearance of the dessert. Greater percentages imparted non-desirable flavour attributes, such as bitterness and acidity. The use of this ingredient as a replacement of commercial inulin in the formulation of source of fibre puddings is possible. However, further research is needed to reduce the off flavours.

Characterization of Portulaca oleracea Whole Plant: Evaluating Antioxidant, Anticancer, Antibacterial, and Antiviral Activities and Application as Quality Enhancer in Yogurt

Purslane (Portulaca oleracea L.) is rich in phenolic compounds, protein, and iron. This study aims to produce functional yogurt with enhanced antioxidant, anticancer, antiviral, and antimicrobial properties by including safe purslane extract in yogurt formulation; the yogurt was preserved for 30 days at 4 °C, and then biochemical fluctuations were monitored. The purslane extract (PuE) had high phenolic compounds and flavonoids of 250 and 56 mg/mL, respectively. Therefore, PuE had considerable antioxidant activity, which scavenged 93% of DPPH˙, inhibited the viability of MCF-7, HCT, and HeLa cell lines by 84, 82, and 80%, respectively, and inhibited 82% of the interaction between the binding between Spike and ACE2 compared to a SARS-CoV-2 inhibitor test kit. PuE (20-40 µg/mL) inhibited the growth of tested pathogenic bacteria and Candida strains, these strains isolated from spoild yogurt and identified at gene level by PCR. Caffeic acid glucoside and catechin were the main phenolic compounds in the HPLC profile, while the main flavor compound was carvone and limonene, representing 71% of total volatile compounds (VOCs). PuE was added to rats' diets at three levels (50, 150, and 250 µg/g) compared to butylated hydroxyanisole (BHA). The body weight of the rats fed the PuE diet (250 µg/g) increased 13% more than the control. Dietary PuE in rats' diets lowered the levels of low-density lipoprotein (LDL) levels by 72% and increased the levels of high-density lipoprotein (HDL) by 36%. Additionally, liver parameters in rats fed PuE (150 µg/g) decreased aspartate aminotransferase (AST), alanine aminotransferase (ALT), and malondialdehyde (MDA) levels by 50, 43, and 25%, respectively, while TP, TA, and GSH were increased by 20, 50, and 40%, respectively, compared to BHA. Additionally, PuE acts as a kidney protector by lowering creatinine and urea. PuE was added to yogurt at three concentrations (50, 150, and 250 µg/g) and preserved for 30 days compared to the control. The yogurt's pH reduced during storage while acidity, TSS, and fat content increased. Adding PuE increased the yogurt's water-holding capacity, so syneresis decreased and viscosity increased, which was attributed to enhancing the texture properties (firmness, consistency, and adhesiveness). MDA decreased in PuE yogurt because of the antioxidant properties gained by PuE. Additionally, color parameters L and b were enhanced by PuE additions and sensorial traits, i.e., color, flavor, sugary taste, and texture were enhanced by purslane extract compared to the control yogurt. Concerning the microbial content in the yogurt, the lactic acid bacteria (LAB) count was maintained as a control. Adding PuE at concentrations of 50, 150, and 250 µg/g to the yogurt formulation can enhance the quality of yogurt.

Legume protein/polysaccharide food hydrogels: Preparation methods, improvement strategies and applications

For the development of innovative foods and nutritional fortification, research into food gel is essential. As two types of rich natural gel material, both legume proteins and polysaccharides have high nutritional value and excellent application potential, attracting wide attention worldwide. Research has focused on combining legume proteins with polysaccharides to form hybrid hydrogels as their combinations show improved texture and water retention compared to single legume protein or single polysaccharide gels, and these properties can be tailored for specific applications. This article reviews hydrogels of common legume proteins and discusses heat induction, pH induction, salt ion induction, and enzyme-induced assembly of legume protein/polysaccharide mixtures. The applications of these hydrogels in fat replacement, satiety enhancement, and delivery of bioactive ingredients are discussed. Challenges for future work are also highlighted.

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.

Rheological properties of dairy desserts: Effect of rice bran protein and fat content

Rice bran protein (RBP) is an alternative plant protein that can be used in a wide range of foods due to its unique functional, nutritional, and hypoallergenic properties. The interactions of RBP with other biopolymers have revealed its feasibility for application in dairy products such as whipped cream and dairy desserts. Therefore, the effects of RBP and fat content on the rheological properties of dairy desserts were investigated. The pH value was not influenced by protein, but the nonfat milk solid content was changed by fat and protein content. All the desserts showed thixotropic properties which were mainly related to the molecular disentanglement at high shear rates. By increasing fat like RBP, the apparent viscosity (η_a ) was increased. Rheological parameters such as n value, thixotropic index, storage (G'), and loss moduli (G'') were increased by RBP. Moreover, the dairy desserts containing RBP and whole milk presented generally higher G', G'', complex modulus, and complex viscosity values, and lower tan δ values. The RBP enriched samples also had a higher hardness and gumminess. Syneresis was decreased by RBP, which was related to the formation of ordered mesh-like structures which enabled the entrapment of more water. There was a positive correlation between the rheological, textural, and physical properties of the dessert with added RBP, and therefore dairy dessert attributes can be improved along with fat reduction. However, a sensory evaluation is needed to unravel the acceptability rate of RBP in fat reduction from the view point of consumers. PRACTICAL APPLICATION: Rice bran protein (RBP) has nutritional and hypoallergenic properties which enable it to apply to many products such as dairy desserts. One of the main concerns in dairy technology is the growing interest in low-fat products due to health problems. RBP showed unique properties which makes the creamy behavior. The rheological results have elucidated the creaminess associated with RBP and can assist in the proper simulation of mouthfeel.

Upgrading the physiochemical and sensory quality of yogurt by incorporating polyphenol-enriched citrus pomaces with antioxidant, antimicrobial, and antitumor activities

Industrial pomaces are cheap sources of phenolic compounds and fibers but dumping them in landfills has negative environmental and health consequences. Therefore, valorizing these wastes in the food industry as additives significantly enhances the final product. In this study, the citrus pomaces, orange pomace (OP), mandarin pomace (MP), and lemon pomace (LP) were collected by a juice company and subjected to producing polyphenols and fiber-enriched fractions, which are included in functional yogurt; the pomace powder with different levels (1, 3, and 5%) was homogenized in cooled pasteurized milk with other ingredients (sugar and starter) before processing the yogurt fermentation. The HPLC phenolic profile showed higher phenolic content in OP extract, i.e., gallic acid (1,702.65), chlorogenic acid (1,256.22), naringenin (6,450.57), catechin (1,680.65), and propyl gallate (1,120.37) ppm with massive increases over MP (1.34–37 times) and LP (1.49–5 times). The OP extract successfully scavenged 87% of DPPH with a relative increase of about 16 and 32% over LP and MP, respectively. Additionally, it inhibits 77–90% of microbial growth at 5–8 μg/mL while killing them in the 9–14 μg/mL range. Furthermore, OP extract successfully reduced 77% of human breast carcinoma. Each of pomace powder sample (OP, MP, LP) was added to yogurt at three levels; 1, 3, and 5%, while the physiochemical, sensorial, and microbial changes were monitored during 21 days of cold storage. OP yogurt had the highest pH and lowest acidity, while LP yogurt recorded the reverse. High fat and total soluble solids (TSS) content are observed in OP yogurt because of the high fiber content in OP. The pH values of all yogurt samples decreased, while acidity, fat, and TSS increased at the end of the storage period. The OP yogurts 1 and 3% scored higher in color, flavor, and structure than other samples. By measuring the microbial load of yogurt samples, the OP (1 and 3%) contributes to the growth of probiotics (Lactobacillus spp) in yogurt samples and reduces harmful microbes. Using citrus pomace as a source of polyphenols and fiber in functional foods is recommended to enhance their physiochemical and sensory quality.

Optimization of wheat dextrin yogurt formulation using response surface methodology

In the current study, response surface methodology was executed to optimize the ingredient formulation and process conditions production such as wheat dextrin, starter culture and incubation time on the responses such as pH, viscosity, syneresis, overall acceptability, L* value and hardness of the wheat dextrin yogurt. The analyses showed that the wheat dextrin yogurts have a pH from 4.09 to 4.98, viscosity from 10,649.5 to 21,410.1 cP, syneresis from 2 to 26.67%, overall acceptability from 5.3 to 7.9, L* value from 81.2 to 84.3 and hardness from 506 to 5943.3 g during the optimization process. From the variance analysis, the R2 of five response variables except hardness is more than 0.73, which indicates the model explained a high proportion of variability. To conclude, based on the response surface 3D plot of the pH, viscosity, syneresis, overall acceptability, L* value, and hardness evaluation, the optimum value for the independent variables are wheat dextrin of 15 g, a starter culture of 25 g, and an incubation time of 8 h for the wheat dextrin yogurt.

Assessing the influence of psyllium as a fat substitute in wheat and gluten-free cookies

Psyllium is a natural fibre with high water absorption capacity and proved nutritional advantages. The aim of this study was to evaluate the potential of psyllium as a fat replacer in sugar-snap cookies. Elaborations were made with wheat flour or maize flour by maintaining the original recipe or replacing the fat by a paste made with different proportion of psyllium and water. Cookies dough rheology and final cookies properties were evaluated. An acceptability test was also carried out. The replacement of fat decreased the values of G', G″ and G*, but increased tg delta to a greater extent in cookies with gluten. Cookies diameter and spread factor decreased and increased both cookies hardness and moisture content. Fat replacement increase L* value of cookies. Variation of the water content did not influence in the rheology of the dough and in the characteristics of gluten-free cookies, but wheat cookies had smaller spread ratio and decreasing hardness for increasing amount of water. Final cookies had low acceptability and this result was more evident in gluten-free cookies. Considering this result, it is difficult to use psyllium as a total fat substitute in this type of product.

Psyllium: a useful functional ingredient in food systems

Psyllium gum is a hydrocolloid found in the husk of seeds from Plantago ovata. Psyllium husk has been used in traditional medicine in areas of India and China. Its consumption has been shown to provide nutritional benefits, such as the capacity to reduce the glycaemic index, to minimize the risk of cardiovascular diseases, to decrease cholesterol and constipation problems and others. Thus, interest in the incorporation of psyllium in food products is twofold. First, it can be a natural alternative to the use of other gums and hydrocolloids considered additives. Second, it can be used to improve the nutritional properties of products in which it is incorporated. However, for this purpose, it is necessary to add great quantities of psyllium. This review analyses the potential use of psyllium in distinct food products, considering its advantages and inconveniences as well as possible solutions for undesired effects. Among the analyzed products there are bakery products and, in particular, gluten-free breads where psyllium has been used as a gluten substitute. The incorporation of psyllium into dairy products such as yogurts and those derived from fruits, among others, is also addressed.

Structural and sensory analysis of compositionally optimized apple jellies enriched with dietary fibre compared to commercial apple jams

The objective of this work was to optimize the formulation of apple jellies enriched with 3 g/100 g of dietary fibre and to compare them with commercial apple jams in terms of structural and organoleptic properties. With that aim, a fibre mix with one part of psyllium and three parts of other fibre variety (apple, bamboo or wheat) was added to apple jelly, and the rheological, mechanical and sensory properties, as well as colour and syneresis (water loss) of the samples at different storage times were studied, and compared to two commercial apple jams. Those properties did not suffer significant changes during 30 days of cold storage, meaning that the product was stable. The reduction of psyllium proportion in the fibre mix (from 1:1 to 1:3) reduced the gumminess of the fibre enriched jellies, keeping the syneresis at 0 g/100 g. The jelly enriched with apple and psyllium fibre was the most similar to commercial apple jams in terms of rheological and mechanical properties. Consumers acceptability of fibre enriched jellies was higher than 72%, being the jelly enriched with bamboo and psyllium fibre the closest to a commercial apple jam, which was the consumer's favourite.

Dietary fiber sources and human benefits: The case study of cereal and pseudocereals

Dietary fiber (DF) includes the remnants of the edible part of plants and analogous carbohydrates that are resistant to digestion and absorption in the human small intestine with complete or partial fermentation in the human large intestine. DF can be classified into two main groups according to its solubility, namely insoluble dietary fiber (IDF) that mainly consists on cell wall components, including cellulose, some hemicelluloses, lignin and resistant starch, and soluble dietary fiber (SDF) that consists of non-cellulosic polysaccharides as non-digestible oligosaccharides, arabinoxylans (AX), β-glucans, some hemicelluloses, pectins, gums, mucilages and inulin. The intake of DF is associated with health benefits. IDF can contribute to the normal function of the intestinal tract and it has an important role in the prevention of colonic diverticulosis and constipation. SDF is extensively fermented by gut microbiota and it is associated with carbohydrate and lipid metabolism, with important health benefits due to its hypocholesterolemic properties. Due to these nutritional and health properties, DF is widely used as functional ingredients in food industry, being whole grain cereals, pulses, fruits and vegetables the main sources of DF. Also some synthetic sources are employed, namely polydextrose, hydroxypropyl methylcellulose or cyclodextrins. The DF content of cereals varies depending on cultivars, their botanical components (pericarp, emdosperm and germ) and the processing conditions they have undergone (baking, extrusion, etc.). In cereal grains, AX are the predominant non-cellulose DF polysaccharides followed by cellulose and β-glucans, while in pseudocereals, pectins are quantitatively predominant.

Influence of the Addition of Potato, Okara, and Konjac Flours on Antioxidant Activity, Digestibility, and Quality of Dumpling Wrappers

To improve the antioxidant activity (AA), digestibility, and quality of fiber-rich dumpling wrappers, potato, okara, and konjac flours were added to wheat flour. The contents of these additional ingredients in the dumpling wrapper were optimized using the response surface methodology and the synthetic evaluation method. The dietary fiber content (DFC) and AA of blend flours and the optimized cooking time (OCT), cooking loss (CL), hardness, chewiness, firmness, color, and sensory evaluation (SE) of dumpling wrappers were evaluated as response quality parameters. The optimized flour was identified containing 17.5 g of potato flour, 8.5 g of okara flour, and 1.2 g of konjac flour per 100 g of blend flour, which resulted in a higher synthetic evaluation index value (0.71 compared with 0.68 for wheat flour). The qualities of the optimized flour dumpling wrappers were compared with those of wheat flour dumpling wrappers to verify the practicality of the optimized flour. The results showed that the optimized flour showed better comprehensive qualities, especially regarding DFC (9.59%, fourfold higher than that of wheat flour) and AA. Furthermore, the predicted glycemic index (GI) of the optimized flour (74.93%) was lower than that of the wheat flour (81.47%). Overall, the addition of potato, okara, and konjac flours can significantly (P<0.05) improve DFC, AA, and digestibility of wheat flour. The optimized flour not only maintains excellent dumpling wrapper quality but also increases the utilization of potato and okara flours, which has great potential for industrial applications.