Research On Odor Of Hyla Rabbit Meat And Its Changing Of Deposition In Vivo

Rabbit meat,as a functional food,which is one of the ideal meat food,because of its high protein,high lysine,high lecithin,high digestibility and low fat,low cholesterol,low urinary amine,low quantity of heat,namely "four high,four low" characteristics,gets gradually the favour of consumers.Our country is the world's largest rabbit production and breeding country,with the improvement of people's health consciousness,rabbit meat consumption demand for residents in China is gradually increased.However,the quality of rabbit meat has been affected by the special odor,with an indirect impact on the development of the whole rabbit industry.So the research on rabbit meat odor has significantly practical significance and social value.The odor of rabbit meat may be affected by mang factors,including breed,gender,feed,composition of fatty acids,processing and castration and so on.Nowadays,intermediate aldehydes were regard as main volatile compounds for rabbit meat odor.Hyla rabbit with high dressing percentage,high disease resistance,well heterosis,well production performance and well inheritance has vast development space and huge social economy value.This paper studied the extraction,separation and identification of Hyla rabbit meat odor,and also studied sedimentary changes of Hyla rabbit meat odor of different age,different parts and different genders.Moreover,the volatile compounds of Hyla rabbit brain,kidney,liver,kidney,perirenal fat and meat were analysed by principal component analysis,clustering analysis and discriminant analysis,exploring the source of Hyla rabbit meat odor and properties.The analysis method of hexanoic acid in Hyla rabbit meat was established,for understanding its distribution and deposition during the growth of Hyla rabbit.The influence factors for formation of hexanoic acid in Hyla rabbit meat was also studied,to improve the quality of the rabbit meat,to develop rabbit meat processing industry,to deodorize and other issues.The experimental conclusions were as follows:?1?SDE method extracted a total of 75 chemical compounds including hydrocarbons,alcohols,aldehydes,acids,esters,ketones,ethers and heterocyclic;the SPME method extracted a total of 41 chemical compounds including hydrocarbons,aldehydes,ketones and esters;the SFE method extracted a total of 39 chemical compounds including hydrocarbons,alcohols,aldehydes,acids,esters and heterocyclic.Extraction categories: SDE > SFE > SPME,extraction quantity: SFE > SDE > SPME and extraction rate:SPME > SFE > SDE.According to the method of odor active value,hexanoic acid,hexanal,octanal,nonanal,?E,E?-2,4-decadienal and 1-octen-3-ol are the key component of rabbit meat odor.?2?SFE-CO₂ technology was employed to extract the odorants in rabbit meat with the Box-Behnken response surface analysis based on single factor experiments,using extraction yield as index.According to the response surface analysis,the optimal extraction condition is: extraction temperature 40.67?,extraction pressure 25.67 MPa,extraction time 3.13 h and extraction yield 98.01%.And for actual operation,the parameters were modified to 40?,25 MPa and 3 h.The extraction yield was 98.11%.Pentanal,hexanal,hexanoic acid and 2-pentyl furan were preliminarily regarded as the main body of rabbit meat odor.?3?Hexanoic acid can be effectly detected in Hyla rabbit meat using gas chromatography with external standard method.The regression equation is: Y=30421x+50838,R²=0.9998.The recovery and RSD were 91.72% and 1.3% respectively.LOD and LOQ were 2 ?g/kg and 8 ?g/kg respectively.The content of hexanoic acid in Hyla rabbit meat was raising trend firstly and downtrend secondly with the increase of day age.The order of hexanoic acid content was: fore leg > abdomen > hind leg > Longissimus dorsimuscle.The content of hexanoic acid in abdomen and hind leg of male Hyla rabbit meat were significantly higher than those in female ones?p < 0.05?.Howere,it has no significant difference in fore leg and Longissimus dorsimuscle between genders.The formation mechanism of hexanoic acid in Hyla rabbit meat is that hexanoic aicd was generated from hexanal under supercritical CO₂ conditions.Part of hexanoic acid was formed from ? oxidation of linoleic acid.Enzyme of LOX indirectly affects the production of hexanoic acid in Hyla rabbit meat.Actually,it affects the hexanal production from lipids.?4?The number of volatile compounds in abdomen of Hyla rabbit was highest among four parts.And that in Longissimus dorsimuscle was lowest.The number of volatile compounds in brains was highest among brains,kidney,liver,perirenal fat and rabbit meat.But the content of volatile compounds in perirenal fat was highest among those five parts.The concentration of volatile compounds in male Hyla rabbit meat was significantly higher than that in female ones?p < 0.05?.Priciple component analysis showed that hexanal,octanal,2-nonenal,decanal and 2-decenal was the main odorants.Cluster analysis showed that the profile of volatile compounds in Longissimus dorsimuscle was totally different from that in fore leg,hind leg and abdomen.Discriminant analysis said that the odor of Hyla rabbit meat was originated from lipids.?5?The content of odor in Hyla rabbit meat was raising trend firstly and downtrend secondly with the increase of day age.The water content,colorimeter,protein,pH of Hyla rabbit meat had no significantly difference with odor of Hyla rabbit meat.Howere,The content of odor in rabbit meat was significantly correlation with total fat content and TBARS?p < 0.05?.