Study on the volatile compounds generated from lipid oxidation of Chinese bacon (unsmoked) during processing

Abstract

In order to investigate the generation of aroma in Chinese bacon (unsmoked), the changes of lipolysis, lipid oxidation, and volatile compounds derived from lipid oxidation (VCDFLO) during processing were analyzed. The results showed that acid lipase activity decreased during the entire process, while neutral lipase and lipoxygenase (LOX) increased from raw meat to the 1 day of dry‐ripening then decreased. Phospholipase increased during dry‐curing then decreased during dry‐ripening. Thiobarbituric acid reactive substances increased from raw meat to the 7 days of dry‐ripening thereafter decreased. Total free fatty acids increased at the end of 1 day of dry‐ripening and decreased subsequently. Thirty‐five VCDFLO were identified; the total peak area of these compounds increased by almost double at the 4 days of dry‐ripening than raw meat and indicated 47.37–50.85% of total 78 volatile compounds in the final products. In conclusion, VCDFLO generation was attributed to lipid‐related enzymes and contributed mainly to the aroma. Practical applications: Chinese bacon (unsmoked) usually produced from high intramuscular fat pork has more intense and long‐lasting aroma, since intramuscular triglycerides are good precursors for most volatile compounds. Understanding the mechanism of aroma formation related to lipid oxidation could help us to improve the product quality and optimize the duration of processing. Therefore, the present work identified the characteristic flavor compounds and provided the changing regularity of these compounds at various stages to facilitate the generation of them by regulating lipases and lipoxygenase (LOX) activities. The work showed that neutral lipase and lipoxygenase (LOX) played important roles during dry‐curing and dry‐ripening. The regulation of lipases and LOX activities can facilitate the generation of volatile compounds of Chinese bacon (unsmoked).

The Changes of the Volatile Compounds Derived from Lipid Oxidation of Boneless Dry‐Cured Hams During Processing

“…The variation trend of free fatty acids during the processing of boneless hams is demonstrated in Table . Total saturated fatty acids (∑SFA), total monounsaturated fatty acids (∑MUFA) and total polyunsaturated fatty acids (∑PUFA) increased drastically from raw ham to the end of resting, and then decreased sharply at the end of ripening, which was consistent with the results of Chinese unsmoked bacon . The increase of free fatty acids composition during the salting and resting stages could be due to the lipolysis of triglycerides and phospholipids .…”

“…The total peak area of 1‐octen‐3‐ol increased significantly during the processing. The increase of 1‐octen‐3‐ol may be correlated with the decrease of moisture content . 1‐Octen‐3‐ol, with a strong mushroom flavor, was derived from the oxidative breakdown of linoleic acid and considered to be a flavor contributor .…”

Correlations among flavor compounds, lipid oxidation indices, and endogenous enzyme activity during the processing of Xinjiang dry‐cured mutton ham

“…1‐hexanol, which is from oleic acid and palmitic acid, has been well reported as a major volatile compound of meat. It is originating from the oxidative breakdown of linoleic acid and has been described as an important meat volatile due to its low odor threshold (Yang et al, ). With the exceptions of 1‐octen‐3‐ol, which have low threshold values, alcohols have higher threshold values than aldehydes and thus have weaker effects on flavor (Marušić et al, ).…”

Aroma and flavor characteristics of commercial Chinese traditional bacon from different geographical regions

“…Many studies have been conducted on Chinese traditional bacon. However, these studies were mainly focused on chemical compounds and their changes during processing (Huang et al, ; Xie et al, ; Yang et al, ; Yu & Sun, ; Yu, Sun, Tian, & Qu, ; Zhang & Zhao, ). The classification of traditional Chinese pork bacon with geographical features by determining their physicochemical properties through chemometric techniques was effective (Guo et al, ).…”