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 byproduct: 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.

The increased production of Greek-style yogurt in the past decade has induced the need for the reintroduction of the nutrients of its byproduct, yogurt acid whey (YAW), into the food system to combat food waste and aid sustainability. However, the processing and treatment of acid whey, which can be environmentally damaging if disposed of incorrectly, can be costly and complex. Upscaling YAW as an ingredient in food products with minimal re-processing is a cost-effective way to bypass the need for further abatement. To span a broad spectrum of baked products (sweet and savory, biologically and chemically leavened, dairy or water based, oven or surface baked, batter or dough, etc.), pilot commercial pizza crust and pancake formulations incorporating acid whey as a functional ingredient were developed. Dimensions and physico-chemical properties of samples were measured at production and over shelf life at room temperature (23 °C). Consumer sensory testing (n = 120 and n = 108, respectively, Just About Right (JAR), nine-point hedonic, purchase intent, and demographics) were conducted for both products. All instrumental trials and analyses (°Brix, aw, color attributes, viscosity, dimension measurements, and texture analysis) were conducted in triplicate for statistical analysis. Cochran’s Q and post-hoc tests on sensory data showed that liking for at least one experimental YAW sample for each of the pizza and pancake formulations were on par with their respective commercial product, despite the reduction of buttermilk, salt and sugar from the YAW formulations. Adding sustainability claims brought the purchase intent on par with the controls. Replacement of water by weight of YAW was more appropriate than by water content of the YAW. Sourness was the main undesirable trait of YAW samples based on penalty analysis. The use of YAW improved the shelf life of baked goods based on their respective failure mechanisms (textural properties and mold growth). YAW is a suitable ingredient in the formulation of sustainable, healthy, safe, and commercially successful baked products that have a tolerance or can benefit from a sour flavor profile.