Effect of Different Sterilization Treatments on the Nutrition and Taste of Soft Canned Saury

Abstract

The potential of ultra-high-pressure sterilization combined with olive oil impregnation for the processing of soft canned saury was evaluated in this paper. Five types of treatment were set up: Unsterilized group without olive oil, ultra-high-pressure sterilization group with olive oil impregnation (UHPSO), ultra-high-pressure sterilization group without olive oil (UHPS), conventional retort sterilization group with olive oil impregnation (RSO), and conventional retort sterilization group without olive oil (RS). The indicators related to the nutrition and taste (e.g. basic nutrients, total amino acids, fatty acids, free amino acids, taste-presenting nucleotides, etc.) of the soft canned saury in different treatment groups were compared and analysed. The results showed that crude fat and crude protein content were higher in the UHPSO group than in the other sterilization treatments, which had higher nutritional value. The amino acid composition of sterilization treatments were in accordance with the FAO/WHO recommendations and there were no limiting amino acids, with the UHPSO group recording the highest amino acid scores, especially for as a good source of supplementary sulphur-containing amino acids and lysine. Compared to conventional retort sterilization, ultra-high pressure sterilization inhibited the oxidative degradation of unsaturated fatty acids, making the soft canned saury were a good sources of n-3 polyunsaturated fatty acids in combination with olive oil impregnation. Compared to the unsterilized group, sterilization treatments resulted in free amino acids and flavoring nucleotides increased. Combining the taste activity values and MSG equivalents, glutamic acid, threonine, aspartic acid, alanine and hypoxanthine were found to contribute significantly to the formation of the umami taste of the soft canned saury, with the UHPSO group displaying the strongest umami taste. In summary, the combination of olive oil impregnation and ultra-high-pressure sterilization sulted in a more nutritious and delicious soft canned saury compared to traditional retort sterilization.

Keywords

• soft canned saury
• olive oil impregnation
• ultra-high-pressure sterilization
• retort sterilization
• nutrition
• taste