Processed cheese analogues incorporating fat-substitutes - 1. Composition, microbiological quality and flavour changes during storage at 5 degrees C

The effects on the perceived flavour of processed cheese analogue (spreadable type), of changes in the milk protein base, and of the substitution of milk fat by starch or microparticulate whey protein were studied. The gross chemical composition (g 100 g(-1) fat 12.3-22.8, protein 11.6-14.4 and carbohydrates 3.2-9.0) of the experimental samples was within the range typical of full- and low-fat commercial processed cheese spreads. Differences in sensory character were not associated with microbial contamination because coliforms were absent, and the counts of total viable count (TVC) yeast and moulds and of aerobic and anaerobic sporeforming bacteria were of no practical significance for example, TVC = 2.4 x 10(3) cfu g(-1)). Products made using high protein skimmed milk powder were notably different in flavour and aftertaste from those made with retentate. Moreover the analogues incorporating anhydrous milk fat were easily distinguished from those containing the other `lipid' types by their higher ratings for `creamy' and `buttery' flavour. Overall intensity of `flavour' `bitterness' and the `intensity' and `persistence' of aftertaste were influenced by storage period. These changes were associated with protein degradation during storage.