Abstract:

In order to explore the accurate sterilization processing with reduced energy, orange juice in bottle was used as the material to subject high temperature-short time (HTST) sterilization for analyzing the lowest sterilization temperature on common bacteria. Computational fluid dynamics (CFD) technology was used to design the mimic experiments of HTST sterilization for orange juice to explore the optimal sterilization time under different temperatures. Results indicated that the optimal sterilization time was 12 min at 120 ℃, 11 min at 125 ℃, 8 min at 130 ℃ or 7 min at 135 ℃. Meanwhile, the energy consumption in above-mentioned four conditions were 127, 150, 217 or 263 W according to the calculation of Carnot cycle. Based on the lowest energy consumption principle, the optimal sterilization processing was 12 min at 120 ℃.

Key words: juice, ultra high temperature short time sterilization, thermal sterilization, computational fluid dynamics (CFD)