Effect of Application of Stabilizers on Gelation and Synersis in Yoghurt

Abstract

Yoghurt and fermented milks were among the most common dairy products consumed in the world, which were estimated to be 8.3 million tonnes in 1999. In Ethiopia, a significant proportion of milk is consumed in its fermented form as Ergo. Ergo (naturally fermented sour milk) has similar properties with yoghurt; it is a semi-solid product and has pleasant aroma and taste. The fermentation process, usually natural, is affected through spontaneous proliferation of the initial raw milk flora at ambient temperature. However, modern yoghurt production is a well-controlled process that utilizes ingredients of milk, milk powder, sugar, fruits, flavoring agents, coloring agents, emulsifiers, stabilizers, and pure cultures of lactic acid bacteria, which are responsible for the fermentation process. Yoghurt is a product of lactic acid fermentation of milk by addition of a starter culture consisting of Streptococcus salivarius sub spp. thermophilus and Lactobacillus delbrueckii sub spp. Bulgaricus. The addition of sweeteners in yoghurt has made it more palatable. Yoghurt with no added flavor is predominantly sour due to the lactic acid produced during fermentation. For better acceptance of such yoghurts by the consumer, fruits, flavoring agents and sweeteners have been added to improve the flavor balance or to mask partially the acetaldehyde flavor characteristics. Therefore the application of stabilizers in yoghurt manufacturing will bring a positive effect on product stability and consumer acceptance. The review of yoghurt manufacturing and associated stabilizers will help for further research study and development work. The objectives of this review is to address The objective of the paper Yoghurt manufacturing, Common principles in yoghurt manufacturing, Ingredients  used in yoghurt manufacturing, Starter culture used in yoghurt manufacturing, Sweeteners  used in yoghurt manufacturing, stabilizers used  in yoghurt,the science of gelatinization and synersis in yoghurt, nutraceutical properties of yoghurt, Physico-Chemical Properties of Yoghurt  and Sensory Properties of Yoghurt.

Keywords: stabilizers, gelation, synersis and  yoghurt