PhD Oral Defense of Yetenayet Tola, Department of Food Science and Agricultural Chemistry
Heat sterilization or canning significantly damages quality of low acid vegetables. So far different attempts have been made to improve quality of canned vegetables either through modification of conventional processing methods or use of novel processing technologies. Both approaches have their own limitations to achieve required quality improvement or hindered by practical applicability in terms of maintaining food safety. However limited attempt have been made in terms of modification of product property (in terms of pH) and combined use of alternative processing techniques to improve quality of canned vegetables. The first part of this study was focused on searching of novel acid infusion mechanism to modify product pH at the slowest point of acidification. The second and third parts of the study investigated the resistance of Bacillus licheniformis spores under different treatments combinations. The fourth part of this work was focused on the study of the influence of acid infusion on quality retention of carrot.