Effects of replacing buttermilk with yogurt acid whey in ranch dressing

摘要

Greek-style yogurt has expanded from 5 to 50% ofthe US yogurt market in the past decade, accompaniedby a corresponding increase in production of its byproduct:yogurt acid whey (YAW). Yogurt acid wheyqualities (e.g., low pH, mineral content, astringency,and saltiness) present challenges for processing, disposal,and ingredient use. A shelf-stable ranch dressingwas formulated by replacing buttermilk in the controlwith YAW and concentrated YAW (6.3 to 25.2 °Brix).Added salt, gums, and acids were adjusted. The effectsof buttermilk substitution on stability were studied onpasteurized samples (8 mo at room temperature). Aconsumer sensory study (n = 96) was conducted utilizinghedonic and just-about-right scales. Purchaseintent and demographic data were also collected. Afocus group (n = 7) evaluated the sensorial attributesof the samples after 6 mo. The experiment was performedin triplicate and all instrumental analyses (pH,soluble solids as °Brix, water activity, refraction index,and color) were conducted in triplicate for statisticalanalysis. Increasing the gum content in YAW samplesresulted in equivalent texture liking compared with thecontrol. Matching the control’s NaCl concentrationresulted in undesirable higher saltiness. The pH of the18.9 °Brix YAW ranch sample without lactic acid addedwas under 4.6, with no effect on flavor liking. Increasingconcentrations of YAW decreased L* and wateractivity, and increased the refractive index and hue.The YAW samples presented minimum changes over8 mo of storage and had better water retention thanthe control. We conclude that 15 to 17 °Brix YAW isthe optimal replacement for buttermilk in a dressing.The formulation of dressings may be accomplished successfully,sustainably, and cost effectively, with minorprocessing adjustment, by substituting buttermilk withYAW.