Postgraduate Program in Food Engineering, Federal University of Santa Catarina, Technology Center, Trindade, 88040-970 Florianópolis, SC, Brazil.
Department of Food Science and Technology, Agricultural Sciences Center, Federal University of Santa Catarina, Florianópolis, Santa Catarina, Brazil.
Food Res Int. 2021 Dec;150(Pt A):110742. doi: 10.1016/j.foodres.2021.110742. Epub 2021 Oct 12.
This work aims to manufacture a new concentrated lactose-free probiotic yogurt. For this purpose, the probiotic Bifidocaterium BB-12 was incorporated in a concentrated lactose-free yogurt, both in its free form and previously encapsulated. Previous cell encapsulation was performed using the spray-drying technique with the following wall materials: lactose-free milk, lactose-free milk and inulin, and lactose-free milk and oligofructose. Thus, three different probiotic powders were obtained and added separately to three fractions of concentrated lactose-free yogurt. The probiotic survival of both powders and yogurts was evaluated during refrigerated storage. Likewise, the viability of starter cultures in yogurt (Lactobacillus bulgaricus and Streptococcus thermophilus) was controlled. In addition, the physicochemical properties of the four yogurts were also measured (color, pH and acidity, and texture properties). All three powders showed good probiotic viability (>8 log CFU g) throughout 120 days of storage at 4 °C. In turn, yogurt formulations (with the addition of powders or free bifidobacteria) presented probiotic viability above 7 log CFU g after storage; as well as the starter cultures (>8 log UFC g). Yogurt with probiotic powder from lactose-free milk showed a more yellowish color; however, these differences would not be detected by the human eye (ΔE < 3.00). The yogurt with bifidobacteria free cells showed a greater post-acidification process (pH 4.18 to 4.02 and titratable acidity 1.52 to 1.89). It was not observed differences for firmness values of yogurt with free cells addition and yogurt with lactose-free milk and oligofructose powder addition. A slight significant decrease in the cohesiveness was observed in the yogurt elaborated with bifidobacteria free cells. The gumminess showed fluctuating values between all concentrated lactose-free yogurts. At the end of this study, we conclude that these probiotic powders can be incorporated into innovative lactose-free yogurts.
这项工作旨在制造一种新的浓缩无乳糖益生菌酸奶。为此，将益生菌双歧杆菌 BB-12 以游离形式和预先包埋形式加入浓缩无乳糖酸奶中。先前的细胞包埋是使用喷雾干燥技术进行的，使用的壁材有：无乳糖牛奶、无乳糖牛奶和菊粉、以及无乳糖牛奶和低聚果糖。因此，获得了三种不同的益生菌粉末，并分别添加到浓缩无乳糖酸奶的三个部分中。在冷藏储存期间评估了两种粉末和酸奶中益生菌的存活率。同样，控制了酸奶（保加利亚乳杆菌和嗜热链球菌）中起始培养物的活力。此外，还测量了四种酸奶的理化特性（颜色、pH 值和酸度以及质地特性）。在 4°C 下储存 120 天期间，所有三种粉末的益生菌活力均>8 log CFU g。反过来，在储存后，添加粉末或游离双歧杆菌的酸奶配方的益生菌活力均>7 log CFU g；以及起始培养物（>8 log UFC g）。含有无乳糖牛奶益生菌粉末的酸奶呈现出更黄的颜色；然而，这些差异不会被人眼察觉（ΔE<3.00）。含有游离双歧杆菌细胞的酸奶显示出更大的后酸化过程（pH 从 4.18 降低到 4.02，滴定酸度从 1.52 增加到 1.89）。未观察到添加游离细胞的酸奶和添加无乳糖牛奶和低聚果糖粉末的酸奶的硬度值有差异。在含有游离双歧杆菌细胞的酸奶中，观察到稠度略有显著下降。所有浓缩无乳糖酸奶中，胶粘性值均呈波动变化。在这项研究结束时，我们得出结论，这些益生菌粉末可以被纳入创新的无乳糖酸奶中。
