Physicochemical evaluation of corn extrudates containing varying buckwheat flour levels prepared at various extrusion temperatures

Investigation of the effects of corn flour, Spirulina powder, and buffalo yogurt on the quality characteristics of gluten-free muffins

This study aimed to investigate the properties of buckwheat flour-based gluten-free muffins formulated by using corn flour (CF), Spirulina powder (SP), and buffalo yogurt (BY) levels as the factors in the Box-Behnken experimental design. The color values, total soluble polyphenol content (TPC), radical scavenging activity (RSA), specific volume, moisture content, and baking loss results were evaluated as the response variables in the design. The buckwheat flour in the control sample was substituted with CF and SP. Cow yogurt was used in the control muffin instead of milk and was substituted with BY at different levels in other samples. Among the response variables, TPC and RSA values were selected for the optimization studies. Decreasing the CF and SP levels in the formulations resulted in observing higher TPC and RSA values. Three optimal formulations were obtained by response surface methodology. Both cow and buffalo yogurt did not change the properties of the muffins adversely compared to milk. Increasing the SP content made the muffins firmer and caused a decrease in the L*, a*, b*, and browning index values of the muffins. However, sensory scores of SP-containing muffins were also satisfactory.

Sustainable utilization of apple pomace and its emerging potential for development of functional foods

Apple pomace, a byproduct of apple processing industry, possesses nutritional components which are of great interests for health aspects. Apple pomace is a good source of dietary fiber, minerals, carbohydrates, phenolic, and antioxidant compounds. These bioactive compounds can be extracted by different extraction techniques which have been comprehensively described in this review article. Furthermore, the incorporation of apple pomace as functional ingredients in different food products like bakery items, extrusion-based snacks, meat, dairy, and confectionary products to improve the commercial value and health benefits has been discussed briefly. This review article can be a helpful tool for industrialists, innovative researchers, and waste management authorities to manage the apple waste in an appropriate and sustainable way.

Buckwheat: an underutilized crop with attractive sensory qualities and health benefits

The pseudocereal buckwheat is one of the ancient domesticated crops. The aim of the present review was to outline the potential of buckwheat as an agricultural crop and brings studies on buckwheat into a new larger perspective combining current knowledge in agricultural history and practice, nutritional and sensory properties, as well as possible benefits to human health. Historically, buckwheat was an appreciated crop because of its short growth period, moderate requirements for growth conditions, and high adaptability to adverse environments. Nowadays, interest in buckwheat-based food has increased because of its nutritional composition and many beneficial properties for human health. Buckwheat is a rich course of proteins, dietary fibers, vitamins, minerals, and bioactive compounds, including flavonoids. Moreover, it contains no gluten and can be used in the production of gluten-free foods for individuals diagnosed with celiac disease, non-celiac gluten sensitivity, or wheat protein allergies. Buckwheat is traditionally used in the production of various foods and can be successfully incorporated into various new food formulations with positive effects on their nutritional value and attractive sensory properties. Further research is needed to optimize buckwheat-based food development and understand the mechanism of the health effects of buckwheat consumption on human well-being.

A Review of the Changes Produced by Extrusion Cooking on the Bioactive Compounds from Vegetal Sources

The demand for healthy ready-to-eat foods like snacks is increasing. Physical modification of vegetal food matrices through extrusion generates significant changes in the chemical composition of the final product. There is a great variety of food matrices that can be used in extrusion, most of them being based on cereals, legumes, fruits, vegetables, or seeds. The aim of this review was to summarize the main effects of the extrusion process on the bioactive compounds content, namely phenolics, terpenes, vitamins, minerals, and fibers of vegetal mixes, as well as on their biological activity. The literature reported contradictory results regarding the changes in bioactive compounds after extrusion, mainly due to the differences in the processing conditions, chemical composition, physicochemical properties, and nutritional value of the extruded material and quantification methods. The thermolabile phenolics and vitamins were negatively affected by extrusion, while the fiber content was proved to be enhanced. Further research is needed regarding the interactions between bioactive components during extrusion, as well as a more detailed analysis of the impact of extrusion on the terpenes since there are few papers dealing with this aspect.

Development, Characterization and Sensory Evaluation of an Extruded Snack Using Fig Molasses By-Product and Corn Semolina

The effects of extrusion process parameters on the physicochemical, pasting and technological properties of ready-to-eat snacks were evaluated. The aim was to develop fortified extruded products with fig molasses by-product powder (FMP), which is created as a result of the production of fig molasses, is not currently used in food industry, and may cause environmental problems. The feed humidity was changed to 14-17-20%, the die temperature was 140-160-180 °C and the ratio of FMP was 0-7-14% at a fixed screw speed of 325 rpm. The study showed that adding FMP to extruded products had a significant effect on colour properties, water solubility and water absorption index properties. İncreasing the FMP ratio had a significant reducing effect on dough properties of non-extruded mixtures such as peak viscosity (PV), final viscosity (FV) and setback viscosity (SB). The optimum conditions for the production of snacks were found to be 7% FMP, 155.44 °C die temperature and 14.69% humidity. It was determined that the estimated values of water absorption index (WAI) and water solubility index (WSI) for the products manufactured under ideal extrusion conditions were close to the obtained values, and that there was no significant difference between the estimated values of the other response variables and their actual values.

Individual or mixing extrusion of Tartary buckwheat and adzuki bean: Effect on quality properties and starch digestibility of instant powder

Introduction

Tartary buckwheat and adzuki bean, which are classified as coarse grain, has attracted increasing attention as potential functional ingredient or food source because of their high levels of bioactive components and various health benefits.

Methods

This work investigated the effect of two different extrusion modes including individual extrusion and mixing extrusion on the phytochemical compositions, physicochemical properties and in vitro starch digestibility of instant powder which consists mainly of Tartary buckwheat and adzuki bean flour.

Results

Compared to mixing extrusion, instant powder obtained with individual extrusion retained higher levels of protein, resistant starch, polyphenols, flavonoids and lower gelatinization degree and estimated glycemic index. The α-glucosidase inhibitory activity (35.45%) of the instant powder obtained with individual extrusion was stronger than that obtained with mixing extrusion (26.58%). Lower levels of digestibility (39.65%) and slower digestion rate coefficient (0.25 min^-1) were observed in the instant powder obtained with individual extrusion than in mixing extrusion (50.40%, 0.40 min^-1) by logarithm-of-slope analysis. Moreover, two extrusion modes had no significant impact on the sensory quality of instant powder. Correlation analysis showed that the flavonoids were significantly correlated with physicochemical properties and starch digestibility of the instant powder.

Discussion

These findings suggest that the instant powder obtained with individual extrusion could be used as an ideal functional food resource with anti-diabetic potential.

Valorization of Common (Fagopyrum esculentum Moench.) and Tartary (Fagopyrum tataricum Gaertn.) Buckwheat in Gluten-Free Polenta Samples: Chemical-Physical and Sensory Characterization

In recent years, increasing attention has been addressed to buckwheat, an interesting minor crop with an excellent nutritional profile that contributes to the sustainability and biodiversity of the agri-food system. However, the high content of rutin and quercitin present in this pseudocereal can elicit undesirable sensory properties, such as bitterness and astringency, that can limit its exploitation in food formulations. The aim of the present study was to characterize six gluten-free porridge-type formulations (called polenta) prepared using corn and buckwheat flour. Specifically, polenta samples were prepared adding common (CB) or Tartary buckwheat (TB) flour at 20% (CB20; TB20), 30% (CB30; TB30), and 40% (CB40; TB40) to corn flour. Product characterization included sensory and instrumental analyses (electronic tongue, colorimeter, and Texture Analyzer). Products containing Tartary buckwheat were darker, firmer, and characterized by a higher intensity of bitter taste and astringency than those prepared with common buckwheat. In this context, the impact of buckwheat species seems to be more important at 30% and 40% levels, suggesting that lower additions may mask the differences between the species. The gathered information could support the food industry in re-formulating products with buckwheat. Finally, findings about the relationship between instrumental and sensory data might be exploited by the food industry to decide/choose what indices to use to characterize new formulations and/or new products.

Influence of replacement of wheat flour by rice flour on rheo-structural changes, in vitro starch digestibility and consumer acceptability of low-gluten pretzels

This study aimed to access the influence of rice flour incorporation on various quality attributes of low-gluten wheat-based pretzels viz., functional, rheological, starch digestibility, color, textural and sensorial properties. Significant increase in swelling power (18.33 ± 0.51) and bulk density (0.58 ± 0.04) was observed in flour blend upon incorporation of rice flour, whereas, significant decrease in oil absorption capacity (0.62 ± 0.09), solubility index (6.72 ± 0.17), foaming capacity (9.67 ± 0.34), and foaming stability (3.39 ± 0.15) was recorded. Pasting properties of samples were studied using a Rapid Visco Analyser which indicated that all the pasting properties increased with an increase in rice flour incorporation. Fourier transform infrared spectroscopic studies revealed no difference in the basic functional groups of flour blend upon the incorporation of rice flour, however, it had a pronounced effect on elastic modulus (G′) of flour blend. In vitro starch digestion characteristics revealed 7.23% surge in slowly digestible starch and 13.36% reduction in rapidly digestible starch of developed low-gluten pretzels upon the incorporation of rice flour. Apparent amylose content (27.3 ± 1.45) and resistant starch content (6.12 ± 0.97) increased and starch digestibility index (69.87 ± 1.72) decreased in developed low-gluten pretzels. In conclusion, the developed low-gluten pretzels had significantly (p < 0.05) higher mineral profile and lightness (L*) and lower breaking strength in addition to having better overall acceptability. This study indicated that substituting wheat flour with rice flour up to a level of 35% affected the quality attributes of developed low-gluten pretzels.

Graphical abstract

Assessment of the Phytochemical and Nutrimental Composition of Dark Chia Seed (Salvia hispánica L.)

Chia seeds are rich sources of different macro and micronutrients associated with health benefits; thus, they may be considered as a functional food. However, the composition depends on the variety, origin, climate and soil. Here, we show a comprehensive characterization of extractable and non-extractable phenolic compounds of dark chia seed Salvia hispanica L. using high-performance liquid chromatography-electrospray ionization-quadrupole time-of-flight (HPLC-ESI-QTOF) and discuss potential health benefits associated with the presence of a number of nutritional and bioactive compounds. We report that dark chia from Jalisco is a high-fiber food, containing omega-3 polyunsaturated fatty acids, essential amino acids (phenylalanine and tryptophan), and nucleosides (adenosine, guanidine and uridine), and rich in antioxidant phenolic compounds, mainly caffeic acid metabolites. Our data suggest that chia seeds may be used as ingredients for the development of functional foods and dietary supplements.

Extrusion of fermented rice-black gram flour for development of functional snacks: Characterization, optimization and sensory analysis

Considering the health benefits of fermentation, extrusion of fermented rice black gram mix flour can lead to developing nutritionally rich expanded snack. Hence, present study details the effect of various extrusion process variables, barrel temperature (100, 110, 120 °C), screw speed (250, 300, 350 rpm) and die opening diameter (3, 3.5 mm) on physicochemical and bioactive properties of extrudates from fermented rice-black gram flour (Rice flour: black gram flour = 3:1). Results indicated that temperature rise led to the production of a more expanded product with higher water solubility index (WSI) and lower water absorption index (WAI). Higher puffing, WSI, and bioactive content were observed in 3 mm die opening extrudates. Interestingly, extrusion cooking of fermented flour has shown a remarkable increment in phenolic content and antioxidant activity from 63.47 up to 210.3 and 7.28 up to 13.889 mg GAE/100 g, respectively. However, rise in barrel temperature showed a negative impact on bioactive attributes. Further, the optimal conditions determined by numerical optimization method for development of fermented flour-based extrudates having superior functional and enhanced bioactive properties were found to be 100 °C temperature, 289 rpm of screw and 3 mm die diameter. Principal component analysis indicated that bulk density-moisture content and phenolic content-antioxidant activity were highly positively correlated, while expansion ratio-bulk density was negatively correlated. The microstructure of extrudates showed continuous and compact structure lacking starch granules. The fuzzy logic analysis revealed that fermented flour-based extruded product had superior overall acceptability over unfermented flour extrudates.

Effects of processing on onion skin powder added extrudates

It is possible to enhance the functional properties of extruded products with the inclusion of fruit and vegetable by-products. Onion skin, a rich source of quercetin and fiber, is considered as waste in the industry and can be used as an alternative ingredient to improve the nutritional value of the extruded products. Three levels (3, 6, and 9%) of onion skin powder (OSP) were added to wheat flour and compared with control (0% OSP). The effect of the extrusion process on accessible quercetin, total phenolic content, and antioxidant activity of the samples were investigated. In addition, carbohydrate digestibility analyses were conducted for the products. Mass spectrometry (LC-MS/MS) results indicated that increasing the OSP level increased the quercetin content. The process caused the release of the entrapped quercetin from OSP, which was revealed by significantly higher quercetin levels for the extrudates. Some of the quercetin was lost during in vitro digestion process. Increasing the OSP level increased antioxidant activity and total phenolic contents of the samples. Total phenolic contents decreased significantly after the processing, yet antioxidant activities were not affected. The extruded products showed high amounts of rapidly available glucose (69.5 g/100 g). The OSP enhancement did not change the carbohydrate digestibility of products. The results indicated that the extrusion process could increase the level of accessible bioactive ingredients, and the level of functional compound addition can be optimized further.