Effect of Fermentation on the Protein Digestibility and Levels of Non-Nutritive Compounds of Pea Protein Concentrate

Effect of Blanching Plus Fermentation on Selected Functional Properties of Mealworm (Tenebrio molitor) Powders

The aim of this study was to determine the effect of blanching followed by fermentation of mealworms (Tenebrio molitor) with commercial meat starter cultures on the functional properties of powders produced from the larvae. Full fat and defatted powder samples were prepared from non-fermented and fermented mealworm pastes. Then the crude protein, crude fat, and dry matter contents, pH, bulk density, colour, water and oil binding capacity, foaming capacity and stability, emulsion capacity and stability, protein solubility, quantity of free amino groups, and protein composition of the powders were evaluated. Regardless of the starter culture used, the blanching plus fermentation process reduced the crude and soluble protein contents of the full fat powders and in general impaired their water and oil binding, foaming, and emulsifying properties. Defatting of the powders improved most functional properties studied. The o-phthaldialdehyde assay revealed that the amount of free amino groups was higher in the fermented powders while sodium dodecyl sulfate polyacrylamide gel electrophoresis demonstrated that the soluble proteins of the fermented powders were composed of molecules of lower molecular mass compared to non-fermented powders. As molecular sizes of the soluble proteins decreased, it was clear that the protein structure was also modified by the fermentation process, which in turn led to changes in functional properties. In general, it was concluded that fermentation of mealworms with blanching as a pre-treatment does not contribute to the functional properties studied in this work. Nevertheless, the results confirmed that the properties of non-fermented powders are comparable to other food protein sources.

Fermentation of Cauliflower and White Beans with Lactobacillus plantarum - Impact on Levels of Riboflavin, Folate, Vitamin B12, and Amino Acid Composition

As diets change in response to ethical, environmental, and health concerns surrounding meat consumption, fermentation has potential to improve the taste and nutritional qualities of plant-based foods. In this study, cauliflower, white beans, and a 50:50 cauliflower-white bean mixture were fermented using different strains of Lactobacillus plantarum. In all treatments containing cauliflower, the pH was reduced to <4 after 18 h, while treatments containing only white beans had an average pH of 4.8 after 18 h. Following fermentation, the riboflavin, folate, and vitamin B12 content of the cauliflower-white bean mixture was measured, and compared against that of an unfermented control. The riboflavin and folate content of the mixture increased significantly after fermentation. Relative to control samples, riboflavin increased by 76-113%, to 91.6 ± 0.6 μg/100 g fresh weight, and folate increased by 32-60%, to 58.8 ± 2.0 μg/100 g fresh weight. For one bacterial strain, L. plantarum 299, a significant 66% increase in vitamin B12 was observed, although the final amount (0.048 ± 0.013 μg/100 g fresh weight) was only a small fraction of recommended daily intake. Measurements of amino acid composition in the mixture revealed small increases in alanine, glycine, histidine, isoleucine, leucine, and valine in the fermented sample compared to the unfermented control.

Harnessing Microbes for Sustainable Development: Food Fermentation as a Tool for Improving the Nutritional Quality of Alternative Protein Sources

In order to support the multiple levels of sustainable development, the nutritional quality of plant-based protein sources needs to be improved by food technological means. Microbial fermentation is an ancient food technology, utilizing dynamic populations of microorganisms and possessing a high potential to modify chemical composition and cell structures of plants and thus to remove undesirable compounds and to increase bioavailability of nutrients. In addition, fermentation can be used to improve food safety. In this review, the effects of fermentation on the protein digestibility and micronutrient availability in plant-derived raw materials are surveyed. The main focus is on the most important legume, cereal, and pseudocereal species (Cicer arietinum, Phaseolus vulgaris, Vicia faba, Lupinus angustifolius, Pisum sativum, Glycine max; Avena sativa, Secale cereale, Triticum aestivum, Triticum durum, Sorghum bicolor; and Chenopodium quinoa, respectively) of the agrifood sector. Furthermore, the current knowledge regarding the in vivo health effects of fermented foods is examined, and the critical points of fermentation technology from the health and food safety point of view are discussed.

Fortification of traditional egg pasta (erişte) with edible insects: nutritional quality, cooking properties and sensory characteristics evaluation

Proximate composition, cooking quality and sensory characteristics of traditional Turkish egg pasta, erişte, fortified with edible insect and legume flours were evaluated. Egg pasta samples were produced using different blends of wheat flour: legume (lentil and white kidney bean) flour and wheat flour: edible insect (mealworm and grasshopper) flour. Optimum cooking time significantly (p < 0.05) increased with the fortification of egg pasta. The fortification of egg pasta with edible insect flours resulted in a reduced volume expansion from 236.7% (control) to 215.6% and 196.9% for grasshopper flour (W:G) and mealworm flour (W:M) samples, respectively. On the other hand, W:M and W:G samples exhibited significantly (p < 0.05) higher nutritional profile in terms of protein, ash and crude fiber content. Results showed that the smoothness of pasta was also influenced; strengthened by addition of white kidney bean flour and weakened by the addition of grasshopper flour. The received scores from sensory evaluation showed that flours including lentil flour (W:L) and white kidney bean flour (W:B) samples had higher flavor and overall acceptability values with compared to the mealworm flour (W:M), grasshopper flour (W:G) and control sample (C).

Health-Promoting Components in Fermented Foods: An Up-to-Date Systematic Review

Fermented foods have long been produced according to knowledge passed down from generation to generation and with no understanding of the potential role of the microorganism(s) involved in the process. However, the scientific and technological revolution in Western countries made fermentation turn from a household to a controlled process suitable for industrial scale production systems intended for the mass marketplace. The aim of this paper is to provide an up-to-date review of the latest studies which investigated the health-promoting components forming upon fermentation of the main food matrices, in order to contribute to understanding their important role in healthy diets and relevance in national dietary recommendations worldwide. Formation of antioxidant, bioactive, anti-hypertensive, anti-diabetic, and FODMAP-reducing components in fermented foods are mainly presented and discussed. Fermentation was found to increase antioxidant activity of milks, cereals, fruit and vegetables, meat and fish. Anti-hypertensive peptides are detected in fermented milk and cereals. Changes in vitamin content are mainly observed in fermented milk and fruits. Fermented milk and fruit juice were found to have probiotic activity. Other effects such as anti-diabetic properties, FODMAP reduction, and changes in fatty acid profile are peculiar of specific food categories.

Nutritional biotransformation in traditional fermented tea (Miang) from north Thailand and its impact on antioxidant and antimicrobial activities

Miang is a traditional fermented tea made from fermentation of Assam tea leaves with mixed microbial culture involving lactic acid bacteria and yeast. Miang has important bioactive benefits such as antioxidant and antimicrobial activity with relevance to health benefits. Miang is categorized into two processes; filamentous fungi growth-based (FFP) and non-filamentous fungi-based (NFP) process, depending on area of production. Further, Miang is also divided into 2 types; astringent Miang and sour Miang, depending on fermentation time. The aim of this research was to determine the important macronutrient biotransformation of Miang diversity under above processes and types and explore the impact on bioactive compounds relevant to antioxidant and antimicrobial activities. During fermentation, pH, total acid, nutritional components, total polyphenols (TP), total tannins (TT), total flavonoids (TF), total catechins (TC), antioxidant activity and antimicrobial activity were evaluated. Miang when fermented for longer sour Miang process compared to shorter time astringent Miang increased crude protein, fiber, and ash contents whereas soluble carbohydrates decreased. Even though TP, TT, TF and TC of sour Miang was lower, the overall antioxidant activity was higher than astringent Miang. This suggests that in addition to the phenolic compounds, other specific phenolics and substances such as biotransformed protein and fat could contribute to antioxidant properties. Additionally, Miang also contains antimicrobial activities against dental caries pathogenic bacteria Streptococcus mutans, gastrointestinal disease causing Vibrio cholerae and Salmonella enterica serovar Typhimurium through likely effects of organic acids and phenolic compounds.

Solid state fermentation of de-oiled rice bran: Effect on in vitro protein digestibility, fatty acid profile and anti-nutritional factors

An experiment was conducted to study the effect of solid state fermentation of de-oiled rice bran (DORB) with Rhizopus oryzae on in vitro protein digestibility, anti-nutritional factors and fatty acid profile. The fermentation of DORB with Rhizopus oryzae significantly reduced the in vitro protein digestibility of DORB (p < .05). The fermentation of DORB with Rhizopus oryzae increased the saturated fatty acid (SFA) content by 46.83%, while decreased the MUFA and PUFA contents by 14.01 and 8.76%, respectively. The n-6 fatty acid content of FDORB increased by 6.19%, while n-3 fatty acid content decreased by 53.92%. The fermentation of DORB resulted in significant reduction in phytate and trypsin inhibitor activity (p < .05). Based on the present result it is concluded that the fermentation of DORB with Rhizopus oryzae improves the n-6 fatty acid profile and brings significant reduction in the phyate and trypsin inhibitor content but fails to improve the in vitro protein digestibility and hence cannot be recommended as a suitable microbe for DORB fermentation.