SENSORY PROFILE ANALYSIS AND VISUAL ASSES SMENT OF HEAT-TREATED MILK

The results of sensory profile analysis and visual assessment of milks subjected to different heat treatments have shown that a taste panel trained in sensory assessment of milk awards milk subjected to thermis ation- and pasteurization processes (short time and long-time heating) and obtained by applying the lower range of high temperature pasteuri zation a good to excellent quality as regards odour and flavour. The s ame taste panel has classified also milk obtained under conditions of UHT treatment to be perfect regarding odour and flavour and awarded a good quality, although with the temperature/ time combinations selecte d sterilization values up to 30 min were applied. In contrast to this milk obtained using the upper range of high temperature pasteurization at process temperatures of 105-125 degrees C and holding times corres ponding to sterilization values of less than 0.3 min has been classifi ed to be ''faulty'' from the sensory viewpoint. The reason for this mi ght be a milk flavour which occurs particularly in the upper range of high temperature pasteurization but is not set free under conditions o f UHT treatment, or is rather ''casted out'' from the milk matrix at t he higher process temperatures of the UHT treatment range and is, thus , no longer effective from the sensory viewpoint. Additionally one sho uld assume that the cooked flavour of UHT milk is today rejected neith er by a trained taste panel from the viewpoint of flavour and odour.