Study On The Law Of Quality Formation Of Yunnan Dried Beef Processing

Dried beef is the natural fermented meat products unique to Yunnan Hui Autonomous Region in China,the traditional dried beef production in cattle hindquarters as raw materials,such as pickled hanging from the production process,belongs to the low temperature fermentation of beef products.At present,the main production of dried beef follow the traditional experience,it is difficult to achieve standardization and safety production,to produce stable quality and safety products.A preliminary study on the production process,safety,preservation technology and other aspects of domestic scholars on the dry,but on the dry production process of physicochemical changes of no and the quality formation characteristics,which leads to the lack of standardized cow dry pickled data basis and theoretical guidance.Based on this,it is necessary to carry out a research,the processing technology of beef cow dry process quality standard form research work rules.The test selected 8 cattle hind legs,from which the stock two muscles(BF)of dried beef production,and raw meat(0d),(30d),air dried salted finish drying for 1months(60d),air drying for 2 months(90d),air drying(120d),3 months air drying for 4 months(150D),(180d)finished cow dry 7 points in process sampling,the physical indexes(moisture,crude fat,salt,nitrite,color,peroxide value,acid value,TBARS,pH,trimethylamine nitrogen,heavy metal content,water activity,moisture migration,mineral composition N-,methylnitrosamino),protein degradation and flavor compounds during fermentation(precursor substances,free fatty acids,volatile flavor compounds)and other quality formation were studied,the main results are as follows:1.With the dried beef production process,the moisture content and water activity decreased,while the salinity increased gradually,helps to control the quality and flavor of dried beef.Health indicators:the cow dry residue of nitrite increased after the first drop,but still lower than the national standards and regulations;dried beef(AV)acid value and peroxide value(POV)content increased gradually.Dried beef processing pH value in the process of change showed a trend of increased first and then decreased,mainly due to protein hydrolysis and fermentation to produce lactic acid interactions lead to.Because the muscles of browning and other reasons,lead to color values of dried beef(L*,a*,b*)changes in the production process,L*showed a rising trend,a*and b*are changing slowly,generally showed a low high low trend.The TBARS value measured by MDA showed a low high low trend during the processing.Bazhong is rich in minerals beneficial to human body.In each stage of dried beef processing,heavy metal content,N-dimethyl nitrosamine,trimethylamine nitrogen and other harmful indicators are less than specified in the national standard.The low field nuclear magnetic resonance(LF-NMR)technique for the detection of each stage of the cow dry water distribution,containing three different states of water in fresh beef,respectively with hydration water,immobilized water,free water.There are three peaks in the finished product,respectively with hydration water,immobilized water and peak oil flow.Total peak area compared with fresh meat decreased.It may be that the amount of water loss in dry cured beef is higher than that of fat.2.The use of GC-MSD for each stage of the dried beef samples setting quantitative analysis identified 24 kinds of free amino acids in dried beef,and with C16:0,C18:0,C18:1n9c and C14:0,these kinds of free amino acids accounted for more than 76%of the total amount of dried beef.The saturated fatty acids in dried beef of Bazhong were mainly C16:0,C18:0 and C14:0,and the content of C12:0 was the second.Unsaturated fatty acids were the main components of C18:1n9c,followed by C18:2n6c,C16:1n7 and C20:3n6,and the contents of unsaturated fatty acids in finished dried cattle in Bazhong decreased significantly compared with those in raw meat(P<0.05).The contents of 8 free fatty acids such as C4:0,C6:0,C8:0 and so on in cattle dried in Bazhong were lower than those in 0.50%.Beef samples in saturated fatty acids(P<0.05)were significantly increased to about 72.6%,and did not change significantly in the process in the next(P>0.05);single unsaturated fatty acid content in the curing stage decreased significantly to 11.69%,significant at the end of air drying after first months(P<0.05)increased,and in the process the next the content did not change significantly(P>0.05)remained at around 20%;polyunsaturated fatty acids in the processing of a few months ago had no significant change(P>0.05),air drying in third months increased to 10.60%,and remained relatively stable in the later period of processing.3.Methods using ~1H-NMR metabonomics to study the metabolites of dried beef in the production process analysis,and multivariate statistical methods find the correlation between the chemical composition and the difference and difference components.Test results have dried beef NMR spectra of 59 metabolites were identified,and these metabolites can be divided into the following categories:Dried beef tastes salty and savory to,and including the sweet and bitter components,the taste system is complex,most content of flavor amino acids showed an upward trend in the machining process,the important flavor substances of glutamic acid,the main umami,increased significantly in the process(P<0.05).The alanine content was highest in the finished product,followed by glutamic acid.The dried beef,detected in three kinds of amine compounds,which were the highest content in raw meat,and creatinine content is 0.14mg/g,finished cattle dry Bazhong creatinine content significantly(P<0.05)increased to 0.59mg/g.Compared with the content of creatinine,the choline content was low,and the content in raw meat was 0.01mg/g.After processed,the content of dried beef in Bazhong was significantly increased(P<0.05)to 0.04mg/g.To several 2-hydroxy butyric acid,3-hydroxy butyric acid,acetate,formate,lactate,fumaric acid,isovaleric acid,malic acid,pyruvic acid,succinic acid and other organic acids detected in dried beef,the highest content of lactate.2-hydroxybutyric acid,3-hydroxy butyric acid and formic acid in raw meat with low content of less than 0.05mg/g,and after pickling and no significant change(P>0.05),still maintain a low content in the finished product,0.02mg/g,0.01mg/g and 0.07mg/g respectively.Fumaric acid and malic acid in raw meat in small amounts,and significantly in after curing(P>0.05)decreased in the finished dried beef in the content of zero.4.55 kinds of volatile flavor compounds were detected in fresh beef,and the types of volatile flavor compounds in beef samples were increased after salting and air drying,and there were 60 kinds of volatile compounds in the samples.The main ingredients are mainly concentrated in aldehydes,alcohols and hydrocarbons,ketones,acids,esters,furan,and aldehydes in raw meat percentage was 33.57%,the content of alcohols finished products after processing dried beef rose to 49.62%.The product contains most kinds of aldehydes.Some of the relatively high relative levels of aldehydes that are detected in aldehydes are sinal,hexanal,and heptaldehyde.The relative content of the ketone is higher:acetone;The relative content of alcohols is positive octanol,hexanol,etc.Hydrocarbon paraffin hydrocarbon and aromatic hydrocarbons with benzene ring structure,high relative content of 12,14,propane,o-xylene,dimethyl benzene,etc.