QUALITY OPTIMIZATION OF HOT FILLED PASTEURIZED FRUIT PUREES - CONTAINER CHARACTERISTICS AND FILLING TEMPERATURES

A mathematical model was developed to describe the pasteurization, by hot filling, of fruit purees. The model assumed that the puree reaches instantaneously a hot-fill temperature and after introduced into the container cooling by conduction takes place. The heat transfer was mod elled by a finite differences method. Vitamin C and pectinesterase wer e used as quality and pasteurization criteria, respectively. Specific filling temperatures combined with container dimensions are required t o achieve a target pasteurization value. However only some of the adeq uate conditions offer final products with maximum quality. Several sim ulations were carried out to investigate the effect of filling tempera ture, container shape, type of cooling medium anal pasteurization valu e on final quality retention expressed as vitamin C retention. Using s tatistical factorial analysis the most important parameters affecting quality were filling temperature and pasteurization value, followed by cooling medium. Shape was not considered significant (p > 0.05). Best quality was achieved with higher hot filling temperatures and small p asteurization values. (C) 1997 Elsevier Science Limited.