Development of Guava probiotic dairy beverages: application of mathematical Modelling between consumer acceptance degree and whey ratio

Abstract

Twenty One guava probiotic dairy beverages (Lactobacillus aciophilus LA-5 "2% vol/vol" "T₁", Bifidobacterium bavidium "2% vol/vol" "T₂" and Lactobacillus aciophilus LA-5 "1% vol/vol" and this ratio in Bifidobacterium bavidium "T₃") were produced using 0, 20, 35, 50, 65, 80 and 100% (vol/vol) (unsalted whey) which is a product of  Ras cheese manufacturing in their formulations and The same percentage interchangeably with cow's milk. The adding of whey from 0 to 100% had highly significant (p<0.001) effect on pH values in T₁ treatments. The highest pH values (5.039 to 5.173) recorded in the T₂ treatments, while less values (4.083 to 4.246) recorded in T₁ treatments. In T₂ treatments, the effect of adding whey on pH and counts of B. bavidium was found to be highly significant (p≤0.001). On the other hand, adding whey during the different treats had highly significant effect (p<0.001) on pH values and L. aciophilus, in contrast; non-significant effect (p=0.609) of adding whey was showed on B. bavidium. In T₁, T₂ and T₃ treatments, the higher values of consumer acceptance degree were 7.267, 7.567 and 7.767 out (9), respectively at 35% whey, while lower values 5 was showed at 0% and 80% whey in T₁ treatments, and (3.233 and 3.867) at 100% whey in T₂ treatments" and T₃ treatments. Mathematical Modelling was created to describe the relationship between consumer acceptance degree (C) and the whey ratio (W) at each type of the previously mentioned starters. Sinusoidal modelling was resulted with a standard error ranging between (0.38 or 0.40).