Fortification of set yoghurts with lemon peel powders: An approach to improve physicochemical, microbiological, textural and sensory properties

Abstract

Lemon peel powder (LPP) is an excellent source of pectin and has been used as prebiotic polysaccharide. This study was conducted to assess the possibility of fortifying yoghurt with LPP (0.25 %, 0.5 % and 0.75 %) to improve the functionality of yoghurt. Physico-chemical properties of LPP as well as pH, acidity, color, total solids, viscosity, water holding capacity, syneresis, microbial, textural and sensory properties of LPP fortified yoghurt during 14 days of storage were evaluated. The results showed that bulk density, swelling, water absorption, emulsifying, and foaming capacity of LPP were 0.548, 8.61, 5.23 ml/g, 14.22 % and 11.33 % respectively. Addition of LPP enhanced the viscosity from 480 mPas to 610 mPas, total solid from 22.73 % to 25.93 %, acidity from 815 mg/100 ml to 1006 mg/100 ml and decreased pH values from 4.83 to 4.52. LPP fortification also improved the water holding capacity, microbial viability, and microstructure. The sensory test revealed that yoghurt with 0.5 % LPP had higher sensory scores and overall acceptability. Based on the data obtained from the current study, the addition of 0.5 % LPP in yoghurt had been suggested to enhance the nutritional quality of yoghurt by providing better physicochemical and organoleptic qualities.

Keywords

• Viscosity
• Syneresis
• Foaming properties
• Emulsifying properties
• Water holding capacity
• Microstructure