Rheological and physico-chemical attributes of lactose hydrolyzed micronutrients rich low lactose yoghurt

Abstract:

The study focuses on the development of low lactose yoghurt by lactose hydrolysis and fermentation process and fortification with micronutrients rich plant sources such as avocado, pumpkin seeds and lemon. The product was optimised for lactose hydrolysis and addition of avocado pulp powder (0.50%), pumpkin seeds powder (0.75%) and fresh lemon juice (0.75%) based on sensory quality. The developed product was analysed for rheology and physico-chemical characteristics; and nutritional quality. Degree of lactose hydrolysis was 54.80% at 0.30% lactase enzyme concentration and fermentation by yoghurt cultures brought down the lactose content to 1.00% (20 - 30% lowered). The lactose hydrolysed micronutrient rich yoghurt showed a significant improvement in the rheological properties such as firmness, consistency, cohesiveness, index of viscosity and apparent viscosity and physico-chemical properties enhanced by reduction in syneresis and setting time. The nutritional quality was improved with respect to fat, protein, minerals and vitamin C. The developed micronutrient rich (minerals and vitamins) low lactose yoghurt possesses superior sensory quality (sweetness and consistency) along with improved nutritional value which can attract lactose intolerant population.