Determination of Some Quality Characteristics and Rheological Properties of Yoghurts Made Using Cow Milk and Soy Drink Mixture Enriched with Pomegranate Peel Extract

Abstract

This study examined the applicability of pomegranate peel extracts (PPE) and microencapsulated pomegranate peel extracts (MPE) in yogurts made with cow’s milk and soy drink mixtures. For preparing PPE, pomegranate peel powders were extracted by 50% ethanol in an ultrasonic water bath. PPE was encapsulated by using a spray dryer. Phytochemical composition and antioxidant activity of PPE and MPE were determined and 0.5% and 1% PPE and MPE were used in yogurt production. Physicochemical, rheological, microbial and sensory properties of the yogurt samples stored at 4 °C were determined during storage. Extract addition affected storage modulus (G') values and lost tangent (tanδ) values. The extract additive prevented the growth of yeasts and moulds and extended the shelf life of the samples. The favorable effect of the extract on taste and aroma was determined in sensory tests. However, the extract contributed to the loss of textural properties such as syneresis and visible viscosity.