Effect of Fruit Acid–Milk Protein–Polysaccharide Interactions on the Physicochemical Properties and Sensory Quality of Low‐Fat Frozen Yoghurt

ABSTRACT Background Flavor plays a crucial role in determining consumer acceptance of frozen delicacies such as ice cream and frozen yoghurt. The type and level of flavoring matter used impart distinct sensory characteristics, and it is essential to identify the minimal amount that provides desirable flavor intensity without affecting the texture and underlying structure of frozen yoghurt matrix. Aim This study aimed to evaluate the effects of type of fruit flavor and their usage levels on the proximate composition, physico‐chemical properties, and sensory attributes of low‐fat (2.0% milk fat) frozen yoghurt with particular emphasis on the influence of fruit‐derived acids and soluble acids on the frozen yoghurt matrix. Methods Two fruit flavors viz., orange crush and pineapple crush each were incorporated at 9.0%, 10.5%, and 12.0% levels by weight in frozen yoghurt formulations to examine their effects on composition, viscosity (of mix), overrun, melting behavior, and sensory properties. Major Findings Increasing fruit crush level significantly ( p ≤0.05) elevated the total carbohydrates and total solids, while ash content decreased; fat and protein content remained unchanged. Pineapple‐flavored samples exhibited higher viscosity (340.60 to 388.40 cP vs 316.73 to 350.57 cP for orange flavored counterpart), acidity, and melting rate (indicating lower melting resistance) compared to orange‐flavored ones, when compared at the same usage level of fruit crush. The overrun of frozen yoghurts tended to decrease with increasing fruit crush usage levels, with pineapple samples showing lower overrun than the ones utilizing orange crush. The increase in viscosity observed in fruit‐flavored mix samples may be attributed to interactions between fruit‐derived pectin and milk proteins, which strengthened the colloidal network of the yoghurt matrix. Additionally, citric acid present in fruit crush possibly partially destabilized casein micelles, influencing gel structure and the acidity of the product. Scientific or Industrial Implications Sensory evaluation revealed that the optimized frozen yoghurt sample (O 2 ) achieved the highest overall acceptability score of 92.10 out of 100.00. The recommended usage level of orange crush was 10.5% by weight of frozen yoghurt formulation in order to obtain orange flavoured low‐fat (2% milk fat) frozen yoghurt, balancing desirable texture, flavor, and overall acceptability.