Sensory Analysis of Greek Style Yoghurt Sauce with Blends of Whey Protein Concentrate and Virgin Olive Oil

Abstract

Aims:  To evaluate the influence of whey protein concentrate (WPC-80) and virgin olive oil fortification on the sensory profile of a Greek style yoghurt sauce and to optimize their inclusion levels for achieving the highest consumer sensory acceptance Study Design:  A laboratory-based product optimization study was conducted using a completely randomized design (CRD), evaluating the sensory response of Greek style yoghurt sauce fortified with varying concentrations of WPC-80 and virgin olive oil. Place and Duration of Study:  This research work was carried out in the Department of Dairy Technology, Dairy Science College, Hebbal, Bengaluru, Karnataka, India, over the duration spanning from December 2024 to October 2025. Methodology:  Cow milk standardized to 3.5% fat and 8.5% SNF was cultured with Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus for Greek style yoghurt preparation. The product was fortified with whey protein concentrate (WPC-80) at inclusion levels of 1%, 2%, and 3% to improve protein content and textural attributes, while virgin olive oil was incorporated at 8%, 10%, and 12% to enhance flavour and mouthfeel characteristics. Sensory quality was assessed by a trained panel of 20 judges using a 9-point hedonic scale for flavour, colour and appearance, body and texture, and overall acceptance. Data obtained from sensory trials were statistically evaluated through ANOVA, and treatment differences were compared using the Critical Difference (CD) test at a 5% probability level (P ≤ 0.05). Results:  Incorporation of 3% WPC-80 improved the flavour, body, and texture of the sauce by strengthening the protein structure, giving the best overall acceptance. For olive oil, 10% addition provided the right level of creaminess, appearance, and taste, while 12% made the sauce too oily and reduced liking. The combination of 3% WPC-80 and 10% virgin olive oil resulted in a stable sauce with the most favourable sensory scores. Conclusion: The optimized formulation with 3% WPC-80 and 10% virgin olive oil was found to be the most acceptable, indicating strong potential for developing a protein-enriched, health-oriented Greek style yoghurt sauce with desirable sensory attributes.