Functional Low Fat Fruit Yoghurt

Abstract

Low fat set yoghurt (0.7%) fortified with different fruit pulps (persimmon, mango and guava) and ratios (5, 10 and 15%, w/w) were prepared and stored at 5±1oC for 14 days. Chemical, rheological, total viable lactic acid bacteria and sensory properties were measured when fresh and at 7 and 14 days of storage period. There were significant (p≤0.05) differences between plain yoghurt (control) and functional low fat fruit yoghurt in the total solids (T.S %), antioxidant scavenging activity (ASA%), total phenolic compounds (TPC) and total flavonoid compounds (TFC), they were increased with the increase of the fruit pulp ratios added. While, the pH value and fat% were decreased with the increase of the fruit pulps percentage. The results showed that pH value decreased with extended storage period. Highest values of ASA, TFC and TPC were belonged to yoghurt fortified with guava, mango and persimmon, respectively at 15 % ratio and at 7 days then decreased. The yoghurt containing guava pulp had the highest total viable lactic acid bacteria count compared with plain yoghurt and other fruits yoghurt. The highest (p≤0.05) apparent viscosity was recorded in yoghurt fortified mango, guava and persimmon pulps, respectively. Yoghurt treatments containing 10% mango, 10% persimmon and 5% guava recorded highest sensory scores in low fat yoghurt compared with plain yoghurt and other ratios. The results of current study demonstrated that addition of fruits to the yoghurt significantly improved the rheological properties, body & texture and flavour and support production of low fat yoghurt with more bioactive compounds.