West Pomeranian University of Technology, Faculty of Food Sciences and Fisheries, Department of Dairy Technology and Food Storage, Papieża Pawła VI street 3, 71-459 Szczecin, Poland.
Polytechnic Institute of Coimbra, College of Agriculture, Department of Food Science and Technology, Bencanta, PT-3045-601 Coimbra, Portugal; Research Center for Natural Resources, Environment and Society (CERNAS), College of Agriculture, Polytechnic Institute of Coimbra, Bencanta, PT-3045-601 Coimbra, Portugal.
J Dairy Sci. 2019 Sep;102(9):7838-7848. doi: 10.3168/jds.2019-16556. Epub 2019 Jun 27.
Frozen yogurt is a type of dairy product that is considered to be a more healthful alternative to conventional ice cream due to its lower fat content and the presence of viable lactic acid bacteria. Lactose-free products are a growing trend in the dairy industry, and lactose-free yogurts and ice creams can both be found on the market. However, lactose-free frozen yogurt has not yet reached the market. In this study, we aimed to investigate the effect of adding κ-carrageenan (0.05, 0.1, and 0.15%) and corn starch (1, 2, and 3%) on acidity, texture, viscosity, overrun, melting properties, color attributes, and sensory characteristics of lactose-free frozen yogurts. Lactose was reduced by enzymatic hydrolysis during the fermentation process. The effectiveness of the hydrolysis was measured by HPLC, and lactose was reduced to 0.05% after 80 min of incubation with the enzyme. The addition of stabilizers did not change overrun and melting properties of frozen yogurt, but it did affect pH, titratable acidity, and color parameters. The product with 0.15% κ-carrageenan had the highest hardness and stickiness values. Moreover, κ-carrageenan had a positive effect on sensory attractiveness of lactose-free frozen yogurt, and it reduced the coarse texture in comparison with the control without stabilizers. A lactose-free frozen yogurt with good quality and nutritional characteristics was produced, particularly with the use of κ-carrageenan as stabilizer.
冷冻酸奶是一种乳制品，由于其脂肪含量较低且含有活菌的乳酸菌，因此被认为是比传统冰淇淋更健康的选择。无乳糖产品是乳制品行业的一个新兴趋势，市场上既有无乳糖酸奶也有无乳糖冰淇淋。然而，无乳糖冷冻酸奶尚未进入市场。在这项研究中，我们旨在研究添加κ-卡拉胶（0.05%、0.1%和 0.15%）和玉米淀粉（1%、2%和 3%）对无乳糖冷冻酸奶的酸度、质地、粘度、膨胀率、融化特性、颜色属性和感官特性的影响。在发酵过程中通过酶水解来减少乳糖。通过 HPLC 测量水解的效果，在 80 分钟的酶孵育后，乳糖减少到 0.05%。稳定剂的添加不会改变冷冻酸奶的膨胀率和融化特性，但会影响 pH 值、滴定酸度和颜色参数。添加 0.15%κ-卡拉胶的产品具有最高的硬度和粘性值。此外，κ-卡拉胶对无乳糖冷冻酸奶的感官吸引力有积极影响，与不含稳定剂的对照品相比，它减少了粗糙的质地。生产出具有良好质量和营养特性的无乳糖冷冻酸奶，特别是使用κ-卡拉胶作为稳定剂。
