Technological characteristics of tofu from soybean coagulated with cardoon flower extract.

The objective of the present study was to develop tofu with soybean-water soluble extract coagulated with cardoon flower (F1) and magnesium chloride (MgCl2, F2). The produced tofu was characterized in terms of physical, chemical, microbiological, and sensory properties during 14 days of storage. The yield of F1 was higher (p < 0.05) (195 g/100 soybean seeds) than F2 (162 g/100 soybean seeds). F1 presented higher moisture, protein, acidity, syneresis, and lipids when compared with F2, and a reduction of these contents during the storage. F1 presented lower hardness, stickiness, springiness, and cohesiveness compared with F2. The acceptability of F1 showed a score of 6.00 and F2 of 4.68, and the purchase intention was 3.22 for F1 and 2.23 for F2. This study recommended the use of cardoon flower at 35% level as it has great potential as a coagulant for the elaboration of tofu with higher yield, and acceptability and reasonable purchasing intention.

Extrato de espinafre como fonte de nitrito em linguiça frescal: atributos de qualidade e estabilidade durante o armazenamento refrigerado / Spinach Extract as a source of nitrite in fresh sausages: quality attributes and stability during refrigerated storage

Introdução: Os consumidores têm inúmeras preocupações em relação à saúde, dentre as quais o consumo elevado de aditivos químicos, como os conservantes, que ao reagir com substâncias presentes nos alimentos podem produzir compostos cancerígenos. Alguns vegetais, como o espinafre, podem ser fontes naturais desses conservantes, e sua aplicação pode aumentar a saudabilidade dos produtos cárneos. Objetivo: Avaliar os efeitos do extrato de espinafre como fonte de nitrito para conservação de linguiças frescais, armazenadas durante 35 dias sob refrigeração. Material e Método: Quatro formulações foram produzidas: controle positivo, com sal de cura comercial (CP), controle negativo, sem sal de cura (CN), extrato de espinafre (EE) e extrato de espinafre pré-convertido por bactérias nitrato-redutoras (EEPC). As linguiças foram avaliadas através da composição centesimal, cor, teor residual de nitrito, TBARS e avaliação microbiológica. Resultados: O sal de cura (CP) resultou em menores alterações na coloração das linguiças frescais. O TBARS aumentou aproximadamente 2,5 vezes (p<0,05) ao longo dos 35 dias, em todas as formulações, e os menores valores, ao final desse período, foram encontrados nas formulações CP e EEPC. Estas mesmas formulações apresentaram os maiores teores residuais de nitrito e menor contagem de BAL e enterobactérias (35 dias), o que comprova que o EEPC é tão eficiente quanto o sal de cura comercial como conservante em linguiça frescal armazenada sob refrigeração. Conclusão: O uso de EEPC pode ser uma alternativa promissora para a indústria cárnea, possibilitando o desenvolvimento de produtos clean label que atendam à demanda por produtos mais saudáveis.

Introduction: Consumers express concerns about chemical additives in the diet, including preservatives, which can produce carcinogenic compounds when interacting with substances present in food. Some vegetables, such as spinach, can be natural sources of preservatives, and their application can increase the healthiness of meat products. Objective: To evaluate the effects of spinach extract as a source of nitrite for the preservation of fresh sausages during 35 days of refrigerated storage. Material and Method: Four formulations were produced: positive control, with commercial curing salt (CP), negative control, without curing salt (CN), spinach extract (EE) and spinach extract pre-converted by nitrate-reducing bacteria (EEPC). The sausages were evaluated for proximate composition, color parameters, residual nitrite content, TBARS, and microbiological characterization. Results: The curing salt (CP) led to a few changes in the color of the fresh sausages. TBARS increased approximately 2.5 times (p<0.05) during the 35 days for all formulations, and the lowest values were found for the formulations CP and EEPC at the end of the storage. These formulations had the highest residual nitrite levels and the lowest LAB and enterobacteria count (35 days), which proves that EEPC is an effective preservative to replace commercial curing salt in fresh sausages subjected to refrigerated storage. Conclusion: The use of EEPC can be a promising alternative for the meat industry, enabling the development of clean-label products that meet the demand for healthier products.

Japanese grape (Hovenia dulcis) powder as an antioxidant agent in Bologna sausages.

BACKGROUND: The Japanese grape (Hovenia dulcis Thunberg) has potential as an antioxidant due to its high content of phenolic compounds in the early maturation stages. In this study, the antioxidant sodium erythorbate (CONTROL) was replaced by Japanese grape pseudofruits dehydrated by freeze-drying (FDP) and oven drying (OP), in Bologna sausages. The commercial natural antioxidant licresse (LS), based on licorice, has also been studied. RESULTS: No significant differences (P < 0.05) were observed for the proximate composition and the texture profile of the Bologna sausages. An increase in pH was observed during storage for all formulations. At 28 days, the treatments FDP and OP were darker (lower L* values) and less red (lower a* values), possibly due to the presence of tannins in these samples, which may have bound with the iron present in myoglobin and minimized the oxidation reactions. The use of different antioxidants affected the nitrite contents of the Bologna sausages during storage. Regarding the lipid oxidation, the Japanese grape powder was more effective in delaying the oxidation reactions in Bologna sausages after 14 and 21 days of storage when compared to LS and the CONTROL, respectively. CONCLUSION: The Japanese grape powders were effective in retarding the lipid oxidation of Bologna sausages, possibly due to the presence of bioactive compounds, such as phenolic compounds, tannins, and ascorbic acid, showing the potential of these pseudofruits as antioxidants for use in meat products. © 2022 Society of Chemical Industry.

Incorporation of natural and mechanically ruptured brewing yeast cells in beef burger to replace textured soy protein.

The use of brewer`s yeast to replace textured soy protein (TSP) in burgers was investigated. Three formulations were made, corresponding to a control formulation with 4% TSP, a formulation containing 4% yeast cells in their natural state, and a formulation made with 4% mechanically ruptured yeast cells, which were characterized for the chemical, technological, and sensory properties. Significant differences were observed for pH and instrumental color between the formulations, with no changes in the visual color evaluation by the untrained assessors. The addition of yeast cells resulted in a higher cooking yield and lower reduction in diameter, contributing to maintaining the shape and juiciness of burgers, which is a positive aspect from the technological point of view. The TSP-based formulation presented higher overall appearance and flavor scores when compared with the other formulations, with no significant differences for the other sensory attributes. The results showed that debittering of yeast-cell biomass is required to remove hop resins and tannins before using in burgers, aimed to improve the product`s acceptance and the purchase intent. The debittered yeast cell biomass can be used in burger formulations with great potential to replace TSP, as an alternative to obtain a free allergen meat product.

ß-galactosidase from Kluyveromyces lactis in genipin-activated chitosan: An investigation on immobilization, stability, and application in diluted UHT milk.

The objective of this research was to evaluate the immobilization of the enzyme ß-galactosidase in a genipin-activated chitosan support. The influence of the number of spheres and substrate concentration on immobilization yield (IY) and enzyme activity (EA) was analyzed using experimental design. Thermal, operational and storage stabilities were assessed, and the enzymatic derivatives were characterized by thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The TGA showed that the enzymatic derivatives kept their thermal behavior, and the SEM images revealed smooth surfaces in all the spheres. The optimized conditions for the immobilization process were 4.57 mg·mL-1 of spheres and a substrate concentration of 10 mM (IY = 84.13%; EA = 24.97 U·g-1). Thermal stability was enhanced at 10 and 37 °C, enabling four successive cycles of lactose hydrolysis in diluted UHT milk. Therefore, the immobilized enzyme in genipin-activated chitosan has potential for lactose hydrolysis and applications in the food industry.

Enriched cereal bars with wine fermentation biomass.

BACKGROUND: Cereal bars are a sweet-tasting, nutritious, and enjoyable source of vitamins, minerals, and fiber. Ingredients can be added to the formulation to improve certain characteristics, such as protein content. Some of these ingredients are derived from yeast from fermentation processes. This study aimed to add value to the residue resulting from the wine fermentation process (wine lees) by applying it in the formulation of cereal bars. RESULTS: Three formulations of cereal bars with different concentrations of autolyzed yeast biomass were developed. The effect of the addition of biomass was investigated by chemical and sensorial analysis. The cereal bar with the highest concentration of autolyzed biomass (5%) showed the highest protein content (73.4 g kg-1 ). The findings regarding acceptance obtained by sensory analysis showed that the samples with 2.5% and 5% autolyzed biomass pleased consumers. CONCLUSIONS: Formulations of autolyzed biomass-based cereal bars have increased protein content as the autolyzed biomass concentration has increased. Moreover, the acceptance of the cereal bars with autolyzed biomass in concentrations of 2.5% and 5% was satisfactory. The use of wine lees in food products is therefore a possible way of adding value to this residue, including, for example, a significant increase in protein. © 2020 Society of Chemical Industry.

Yeast (Saccharomyces cerevisiae): evaluation of cellular disruption processes, chemical composition, functional properties and digestibility.

The objective of this study was to evaluate yeast (Saccharomyces cerevisiae) from beer fermentation in its natural form (NY) and subjected to different processes of cellular ruptured [mechanical method using ultrasound (MRY) and modified autolysis using NaCl and ethanol (MAY)] regarding functional and digestibility properties, comparing them with textured soy protein (TSP). Ultrasound treatment resulted in 42% disruption efficiency and the micrographs obtained from scanning electron microscopy analysis showed important morphological modifications due to processes of cellular ruptured action. MRY cells presented more pronounced damage than LN, which suggests the rupture of the cell wall and exit of the internal material to the medium. NY, MRY, MAY, and TSP presented a very close composition concerning the protein content, ranging from 39.32 to 43.80% and moisture of 0.07-0.14%. In vitro digestibility of brewing yeast samples equated the digestibility of TSP (higher than 94%). Cellular disruption with ultrasound (MRY) caused an increase in foaming ability, stability and also oil retention capacity (8.82 mL of oil/g of protein). Modified autolysis (MAY) resulted in higher water holding capacity (14.50 g of water/g of protein) and index of water solubility (greater than 64%) with a decrease in their emulsifying properties. The highest water absorption capacity was presented by the TSP and NY. Therefore, in its different forms, yeast can be applied as a functional and technological ingredient in the food industry, with significant technological capabilities and potential applications.