EFFECT OF HEAT TREATMENT ON k-CARRAGEENAN GELATION IN MILK

摘要: Carrageenans are extensively used for the stabilisation of dairy products. Heat treatment is an essential part processing to ensure bacteriological safety product and also aids hydration hydrocolloid when present. In this work we examine effect various heat treatments on temperature dependent gelation K-carrageenan in milk, using small deformation rheology at 0.08Hz applied stress 5mPa. Skim milk was heated temperatures ranging from 70-150°C 15-300 seconds. K- Carrageenan added either unheated skim or preheated milk. The anhydrous form dispersed hydrated ultrafiltrate (SMUF). It found that gel strength increased with reached a maximum approximately 110°C. Prolonged heating higher resulted loss strength. decrease pH changes ionic equillibria due did not have profound carrageenan gelation. concluded brought about physicochemical casein micelles, which influenced rigidity flexibility milk-carrageenan network. likely forms complex K-casein surface micelles. has been treated below 90°C, remains attached At elevated dissociates micelles hence K-carrageenan/casein becomes detached This results increase network, manifested by modulus gels. per se interfere interaction between K-casein.