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.

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.

Esse trabalho teve como objetivo melhorar as condições higiênico-sanitárias dos alimentos comercializados na Feira do Produtor do município de Laranjeiras do Sul-PR para garantir a qualidade dos alimentos e a saúde dos consumidores. Para isso, foi inicialmente realizada uma pesquisa exploratória das condições higiênico-sanitárias dos ambientes de preparo, manipulação e comercialização dos alimentos a partir de visitas técnicas e diagnósticos das condições das propriedades dos agricultores e da comercialização de alimentos na feira. As não conformidades identificadas durante essa etapa do trabalho foram utilizadas para elaborar o curso de BPF baseado na legislação federal vigente focado, porém, na realidade dos feirantes. Os cursos foram ministrados em três locais para grupos de agricultores e participantes da feira, totalizando 101 pessoas. Após a execução dos treinamentos, foi realizado o monitoramento das atividades para observar o atendimento às boas práticas na feira e os resultados foram analisados de forma qualitativa e interpretativa. Como resultado, conclui-se que os cursos foram eficazes, pois melhorias significativas foram constatadas no local do estudo, como a melhoria dos hábitos de higiene praticados pelos feirantes, como práticas adequadas no preparo e comercialização de alimentos.

No abstract

Spent yeast biomass is one of the residues of brewing. It is specifically the second-largest residue from brewing industry. Most of the spent yeast is sold at low prices, or disposed as waste or used as animal feed. Spent yeast biomass is predominantly composed of proteins, and it has a high biological value, being an excellent source of high-quality protein, comparable in value with soy protein. Therefore, spent yeast biomass has great potential for use in foodstuffs for human consumption. The objective of this work was to evaluate the influence of cell rupture over the drying kinetics of spent yeast biomass using mathematical models (Lewis and Page). Also, to verify the influence of cell rupture method over the amount of protein. The cellular rupture was performed by two methods (chemical method and physical method: ultrasound). The drying process was performed by freeze-drying, and the parameters of the models were obtained using the non-linear regression (Generalized Reduced Gradient Nonlinear Optimization Code). Mathematical models of drying kinetics showed a strong correlation with the experimental data, R² > 0.96. The disruption process did not significantly affect the drying time and protein content. But the cellular autolysis improves the protein digestibility since the proteins will be totally available to the digestive enzymes and also increase the bioavailability of nutrients.