基于作者前期的研究基础，本文将进一步探讨超声波辅助浸渍真空预冷（Immersion vacuum cooling with ultrasonic assistance，IVCUA）对西式火腿挥发性风味组分和微生物数量变化的影响。通过与浸渍真空预冷（Immersion vacuum cooling，IVC）、真空预冷（Vacuum cooling，VC）和风冷（Air blast cooling，AB）等预冷方式作对比，并以预冷后西式火腿的电子鼻、GC-MS和微生物结果分析为评价指标。电子鼻分析结果表明，电子鼻能够较好地区分不同预冷方式处理组西式火腿挥发性风味物质的差异。GC-MS分析结果表明，相比于AB处理组西式火腿中检出的106种挥发性风味物质，VC、IVC和IVCUA处理组中分别检出66、70和77种，且损失的种类大部分为对风味贡献不大的醇和烃类。相比VC组和IVC组而言，IVCUA组在对风味贡献大的醛类、酮类、酯类等挥发性风味物质上有更小的损失。菌落总数和乳酸菌数量变化结果表明，IVCUA组具有较AB、VC和IVC组更低的菌落总数和乳酸菌数量，表明其具有更长的货架期。综上所述，IVCUA组作为一种创新的预冷方式对熟肉制品的预冷是可行的。
Based on the author’s previous study, immersion vacuum cooling with ultrasonic assistance (IVCUA), is further compared with immersion vacuum cooling (IVC), vacuum cooling (VC) and air blast cooling (AB) for the change of volatile compounds and microbial count in cooked pork ham. Electronic nose analysis results indicated that the differences on the volatile flavor compounds of cooked pork hams treated by different cooling methods could be sensitively detected using the electronic nose. The results of GC-MS analysis demonstrated that there were significant difference on the compounds of volatile flavor of cooked pork ham treated by different cooling methods, and 66, 70, 77 and 106 volatile flavor compounds were detected for VC, IVC, IVCUA and AB samples, respectively. VC, IVC and IVCUA samples had a higher loss on alcohol and hydrocarbon compared to those treated by AB. However, these losses didn’t produce a significant effect on the total produced flavors. Compared to IVC and VC samples, IVCUA samples had more compounds of volatile flavor including aldehydes, ketones and esters, which play an important role in the formation of total flavors. In addition, it was concluded that samples treated by IVCUA had a lower total viable count and lactic acid bacteria count compared to those subjected to AB, VC and IVC treatment during cold storage, indicating a longer shelf-life. Results confirmed that IVCUA is reasonable to cool the cooked meat products as an innovative cooling technology.