Study On The Effect Of Lipid On The Flavour In The Pork Of Rongchang

Based on domestic and international factors in the study of effects on meat flavour, in order to deeply understand the relationship between Rongchang pork and its lipid, the experimental subject chose Rongchang pig meat as raw materials, investigate the effect of lipid on the Rongchang pork from 3 different aspects, and these results can be used in generalization of Rongchang pork. The major findings are as follows:1 Study on the flavour contribution of phospholipid and triglyceride to Rongchang porkThe longissimus muscle of Rongchang pig was eatracted selectively using petroleum sprit and chloroform with methanol respectively. Sensory analysis showed that the sensory property were roasted when the phospholipids and triglycerides were removed, while the pork characteristic aroma score were significantly low (p<0.01) compared to the petroleum spirit test. Electronic nose analysis showed that similar degree of control pork and petroleum spirit defatted pork is 78.13%, however similar degree of control pork and Chloroform-methanol defatted pork is 64.59%. The volatile compounds in Chloroform-methanol defatted pork reduced evidently compared with control pork and petroleum spirit defatted pork. Percentage of lipid-aldehydes, mallard-aldehydes, ketones, alcohols, esters, sulfur compounds and nitrogen compounds were closed except of furans and alkanes in control pork and petroleum spirit defatted pork, and both of them were differ sharply with Chloroform-methanol defatted pork. Phospholipid contained higher percentage of polyunsaturated fatty acids than triglyceride, such as C18:2 and C20:4. triglycerides had little effect on the Rongchang pork characteristic and meaty flavour, but phospholipid was.2 Contribution of water soluble components in the lipids to the aroma of cooked Rongchang porkDifferent treatment of lipids were compared for differences in odor and volatile composition measured using electronic nose, sensory test and headspace solid-phase microextraction (HS-SPME) coupled to GC-MS. Lipids in the lean extracted by chloroform with methanol was washed by water to remove the water soluble compounds. Much less compounds and less percentage of furans, alcohols, esters, sulfur compounds and Millard-aldehydes were identified in washed lean lipids, and they can be clearly distinguished by electronic nose and sensory test; Lipids in the fat tissue extracted by chloroform with methanol was washed by water to remove the water soluble compounds. Not much less compounds were identified in washed lean lipids, and they can not be clearly distinguished by electronic nose and sensory test, there is less water soluble compounds in the fat lipids.3 Contribution of lean, fat to the aroma of cooked Rongchang porkFour composites were formulated by 80:20 lean to fat ratios:beef lean/beef fat, beef lean/pork fat, pork lean/pork fat, and pork lean/beef fat. Sensory analysis showed that regardless of species fat type, beef flavour was higher in samples made with beef lean, and pork flavour was higher in samples made with pork lean. Four single species formulations were made:pork with 5% fat, pork with 10%fat, pork with 15%fat, pork with 20%fat. Sensory analysis showed that meaty flavour was not increased in patties formulated with higher fat levels. Electronic nose can not clearly discriminate four patties formulated with different fat levels, similar degree of four patties is high. The volatile compounds in four patties formulated with different fat levels were very similar. Lipid in the lean contain higher percentage of phospholipids than in the fat, and Lipid in the lean contain lower percentage of triglyceride than in the fat. Phospholipids in the lean contain higher percentage of polyunsaturated fatty acids than in the fat. Polyunsaturated fatty acids were attacked by free radicle easily and generate volatile compounds in the meat.