Vol. 12, Issue 6 (2023)

Author(s):
Sreema TC, Geo Thomas and Adarsh M Kalla

Abstract:
The focus of the present study was to explore microwave (MW) treatment to the yoghurt starter microbes and evaluate the effect on their growth. Also, to develop a new processing technique in minimising acid whey production in Yoghurt cheese manufacture. The propagated experimental yoghurt cultures were subjected to MW treatment (180W for 3 min) and were inoculated in yoghurt milk for the preparation of yoghurt cheese by traditional method (Strained/Greek yoghurt (SY)) and new method (Greek style yoghurt (GSY)). The total solids (19% and 23%) and amount of culture addition (2% and 4%) were optimized in both the methods of yoghurt cheese manufacture. Desirable acidity and better sensory and textural properties were observed in SY with 2% culture and 23% solids and similarly for GSY with 4% culture and 23% solids. The comparative study of both the methods using optimised combination were carried out after testing for acidity and pH, physico chemical, texture and sensory analysis, nutritional analysis and yield. The GSY was higher in lactose and ash but lesser protein content when compared to the SY. The MW treatments to cultures did not have any impact on composition of the developed product. There was significant (p<0.05) difference between the acidity and pH values of control and MW treated cultures in GSY production. The developed GSY with 23% solids showed significantly (p<0.05) higher textural properties when compared to SY with 23% solids. There was significantly (p<0.05) higher hardness and consistency for MW treated samples when compared to the control GSY and SY. Sensory attributes were significantly (p<0.05) higher in GSY with 4% control and MW treated culture when compared to SY. The nutritional value of SY provides 120.25 kcal/100gm whereas GSY provides 121.29 kcal/100gm. The yield of the GSY incubated in cups, was approximately 100% whereas 50-55% of yield was observed in the SY. The developed GSY with 23% solids and 4% culture is the best alternative to SY. The MW treatment to cultures also enhanced the developed product.