Department of Food Hygiene and Control, Faculty of Veterinary Medicine, University of Sadat City, Sadat City, 32897, Egypt.
Food Technology Department, Arid Lands Cultivation Research Institute, The City of Scientific Research and Technological Applications (SRTA-City), Alexandria, 21934, Egypt.
Sci Rep. 2022 Aug 4;12(1):13401. doi: 10.1038/s41598-022-17633-x.
The current study aimed to figure out the effect of using a combination of 2% inulin, and 2% Fructo-oligosaccharides (FOS) with Lactobacillus acidophilus and their bacteriocin on some yogurt properties such as coagulation time, extending the shelf life of set yogurt and its microbiological quality, also the acceptance by consumers. The results indicated that coagulation time increased by 22.75% in yogurts prepared with Lactobacillus acidophilus and their bacteriocins compared to the control, and titratable acidity increased gradually in all treatments during storage. Hence control acidity (%) increased from 0.84 ± 0.02 at zero time to 1.23 ± 0.03 after 14 days of cold storage, while treatment (T4) was 0.72 ± 0.01 at zero time and reached 1.20 ± 0.5 after 39 days at the same conditions. The sensory properties showed the superiority of inulin, FOS, and Lactobacillus acidophilus bacteriocin groups. Lactobacillus bulgaricus, Streptococcus thermophiles, and Lactobacillus acidophilus count increased in the treatments compared to the control group, with an extended shelf life to 39 days of storage in the medicines containing lactobacillus acidophilus bacteriocin. Coliforms, Moulds, and yeasts did not detect in the treatments comprising 2% inulin, 2% FOS, and lactobacillus acidophilus bacteriocin for 39 days of refrigerated storage. This study proved that 2% inulin, 2% FOS, and Lactobacillus acidophilus bacteriocin fortification extended the shelf life by more than 5 weeks.
本研究旨在探讨在酸奶中添加 2%菊糖和 2%低聚果糖（FOS），以及嗜酸乳杆菌和其细菌素对酸奶某些特性的影响，如凝乳时间、延长凝固型酸奶的货架期及其微生物质量，以及消费者的接受程度。结果表明，与对照组相比，添加嗜酸乳杆菌和其细菌素的酸奶凝乳时间延长了 22.75%，且所有处理组的滴定酸度在储存过程中逐渐增加。因此，对照组的酸度（%）从零时间的 0.84±0.02 增加到冷藏 14 天后的 1.23±0.03，而处理组（T4）从零时间的 0.72±0.01 增加到 39 天后的 1.20±0.5。感官特性表明，菊糖、FOS 和嗜酸乳杆菌细菌素组具有优势。与对照组相比，处理组中的保加利亚乳杆菌、嗜热链球菌和嗜酸乳杆菌的数量增加，添加嗜酸乳杆菌细菌素的处理组的货架期延长至 39 天。在包含嗜酸乳杆菌细菌素的处理组中，39 天冷藏储存期间未检测到大肠菌群、霉菌和酵母菌。本研究证明，添加 2%菊糖、2% FOS 和嗜酸乳杆菌细菌素可将货架期延长 5 周以上。
