Abstract:
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 modelled by a finite differences method. Vitamin C and pectinesterase were used as quality and pasteurization criteria, respectively. Specific filling temperatures combined with container dimensions are required to achieve a target pasteurization value. However, only some of the adequate conditions offer final products with maximum quality. Several simulations were carried out to investigate the effect of filling temperature, container shape, type of cooling medium and pasteurization value on final quality retention expressed as vitamin C retention. Using statistical 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 pasteurization values.
