CHANGES IN APPLE JUICE FLAVOR COMPOUNDS PORING PROCESSING

Apple juice flavor fractions were collected at several stages during a commercial process. Replicated experiments were designed to collect s amples from untreated pulp, from enzyme treated pulp, after pectinase treatment, after microfiltration (MF), and after pasteurization. Addit ional juice heating experiments were carried out. Six apple juice flav or compounds were identified based on to retention times and reported studies. The flavor profile changed at the different stages of the pro duction line. Temperatures used (similar to 57.2 degrees C) for enzyme activation and MF tended to increase flavor compounds in apple juice except iso-butyl acetate. The higher temperatures used (similar to 85 degrees C) for pasteurization decreased all flavor compounds except pr opyl butyrate which increased. Results indicate apple juice may contai n heat activated precursors of identified flavor compounds.