Department of Food Science, Cornell University, Ithaca, NY 14853.
Department of Food Science, Cornell University, Ithaca, NY 14853.
J Dairy Sci. 2019 Sep;102(9):7874-7883. doi: 10.3168/jds.2018-16158. Epub 2019 Jul 10.
Greek-style yogurt has expanded from 5 to 50% of the US yogurt market in the past decade, accompanied by a corresponding increase in production of its by-product: yogurt acid whey (YAW). Yogurt acid whey qualities (e.g., low pH, mineral content, astringency, and saltiness) present challenges for processing, disposal, and ingredient use. A shelf-stable ranch dressing was formulated by replacing buttermilk in the control with YAW and concentrated YAW (6.3 to 25.2 °Brix). Added salt, gums, and acids were adjusted. The effects of buttermilk substitution on stability were studied on pasteurized samples (8 mo at room temperature). A consumer sensory study (n = 96) was conducted utilizing hedonic and just-about-right scales. Purchase intent and demographic data were also collected. A focus group (n = 7) evaluated the sensorial attributes of the samples after 6 mo. The experiment was performed in triplicate and all instrumental analyses (pH, soluble solids as °Brix, water activity, refraction index, and color) were conducted in triplicate for statistical analysis. Increasing the gum content in YAW samples resulted in equivalent texture liking compared with the control. Matching the control's NaCl concentration resulted in undesirable higher saltiness. The pH of the 18.9 °Brix YAW ranch sample without lactic acid added was under 4.6, with no effect on flavor liking. Increasing concentrations of YAW decreased L* and water activity, and increased the refractive index and hue. The YAW samples presented minimum changes over 8 mo of storage and had better water retention than the control. We conclude that 15 to 17 °Brix YAW is the optimal replacement for buttermilk in a dressing. The formulation of dressings may be accomplished successfully, sustainably, and cost effectively, with minor processing adjustment, by substituting buttermilk with YAW.
希腊式酸奶在过去十年中已从美国酸奶市场的 5%增长到 50%，其副产品酸奶酸乳清（YAW）的产量也相应增加。酸奶酸乳清的质量（例如低 pH 值、矿物质含量、涩味和咸味）给加工、处理和配料使用带来了挑战。通过用 YAW 和浓缩 YAW（6.3 至 25.2°Brix）替代基础酸奶制作出一种货架稳定的牧场调味料。调整了添加的盐、胶和酸。研究了巴氏杀菌样品（在室温下 8 个月）中替代乳清的稳定性。进行了一项消费者感官研究（n = 96），使用了愉悦度和恰到好处的量表。还收集了购买意向和人口统计数据。焦点小组（n = 7）在 6 个月后评估了样品的感官属性。该实验重复进行了三次，所有仪器分析（pH 值、可溶性固体作为°Brix、水活度、折射指数和颜色）都进行了三次，以进行统计分析。增加 YAW 样品中的胶含量可获得与对照品相当的口感喜好。将对照品的 NaCl 浓度匹配会导致不可取的更高咸味。未添加乳酸的 18.9°Brix YAW 牧场调味汁的 pH 值低于 4.6，对风味喜好没有影响。YAW 浓度的增加降低了 L*和水活度，增加了折射指数和色调。YAW 样品在 8 个月的储存期内变化最小，并且比对照品具有更好的保水性。我们得出结论，15 至 17°Brix 的 YAW 是调味汁中替代乳清的最佳选择。通过用 YAW 替代乳清，只需进行少量加工调整，就可以成功、可持续且经济有效地配制调味料。
