Bertolo Angélica Patrícia, Biz Ana Paula, Kempka Aniela Pinto, Rigo Elisandra, Cavalheiro Darlene
1Food Engineering and Chemical Engineering Department, State University of Santa Catarina, BR 282, km 573, Pinhalzinho, Santa Catarina 89870-000 Brazil.
2Federal University of Paraná, Curitiba, Paraná Brazil.
J Food Sci Technol. 2019 Aug;56(8):3697-3706. doi: 10.1007/s13197-019-03833-3. Epub 2019 Jun 11.
The objective of this study was to evaluate yeast () 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.
本研究的目的是评估啤酒发酵天然形式（NY）以及经过不同细胞破碎处理[使用超声波的机械方法（MRY）和使用氯化钠及乙醇的改良自溶法（MAY）]的酵母在功能和消化特性方面的表现，并将它们与大豆组织蛋白（TSP）进行比较。超声处理导致42%的破碎效率，扫描电子显微镜分析获得的显微照片显示，由于细胞破碎作用过程，酵母呈现出重要的形态学变化。MRY细胞比NY细胞呈现出更明显的损伤，这表明细胞壁破裂且内部物质释放到培养基中。NY、MRY、MAY和TSP在蛋白质含量方面的组成非常接近，范围在39.32%至43.80%之间，水分含量在0.07%至0.14%之间。啤酒酵母样品的体外消化率与TSP相当（高于94%）。超声细胞破碎（MRY）导致起泡能力、稳定性以及持油能力增加（8.82 mL油/g蛋白质）。改良自溶法（MAY）导致更高的持水能力（14.50 g水/g蛋白质）和水溶性指数（大于64%），但其乳化特性降低。TSP和NY的吸水能力最高。因此，酵母的不同形式可作为功能性和工艺性成分应用于食品工业，具有显著的工艺能力和潜在应用价值。
