Lipolysis and lipid oxidation during processing of Chinese traditional smoke-cured bacon

• Published in: Food chemistry 2014-04, Vol.149, p.31-39
• Main Authors: Huang, Yechuan, Li, Hongjun, Huang, Tian, Li, Feng, Sun, Juan
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; Food Handling; Lipase - chemistry; Lipid oxidation; Lipids - chemistry; Lipolysis; Lipoxygenase - chemistry; Meat Products - analysis; Medical sciences; Muscle, Skeletal - chemistry; Muscle, Skeletal - enzymology; Oxidation-Reduction; Smoke-cured bacon; Swine; Tobacco, tobacco smoking; Toxicology
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2013.10.081

•Relationship between lipolysis and oxidation in bacon is studied using APLSR.•Both triacylglycerols and phospholipids contribute to free fatty acid.•Preferential lipolysis is found in both phospholipids and triacylglycerols.•Autoxidation is the main cause of muscle lipid oxidation.•Phospholipid degradation promotes lipid oxidation, whereas triacylglycerol not. Lipolysis and lipid oxidation as well as the relationship between them during processing of Chinese traditional smoke-cured bacon were studied by evaluating the changes in physicochemical parameters, lipase and lipoxygenase (LOX) activities, lipid content, fatty acid composition, peroxide value (POV), and thiobarbituric acid reactive substances (TBARS). Besides phospholipids, triacylglycerols (TAG) were an important source of free fatty acids in bacon, resulting in an increase in free fatty acid content in the mid-late stage of processing, whilst phospholipids hydrolysed intensely in the early stage. Preferential lipolysis was observed for polyunsaturated fatty acids in phospholipids and for linoleic and palmitic acids in TAG. The lipolysis of TAG and phospholipids was independent and catalysed by acid lipase and phospholipase, respectively. ANOVA-partial least squares regression (APLSR) analysis showed that POV and TBARS were poorly related to LOX and closely associated with phospholipid degradation. Therefore, autoxidation may be the main cause of muscle lipid oxidation in smoke-cured bacon, which was promoted by phospholipid hydrolysis.