| In this experiment,Harbin dried sausage is the object of study,which were added mixed spice,without spices,pepper powder,pepper.In the natural fermentation process,Microbiological,physical and chemical properties of volatile flavor compounds were measured?The aims of this study were to investigate the effects of Strains and volatile flavor compounds,as well as the changes of strains to contacting with formation pathway of the flavor.A further aim was to provide a theory basis in productiing security dried cured salami and developing new products.The contents and results were as follows:1.The changes of strains of dry fermented sausages in the fermentation eycle using SPSS significant were analyzed.The results showed that:the colony formine unit had a increased trend then a increased trend in four selective Medias(PCA?MRS?MSA?PDA).Total bacteria count of each group was spice mixed group<pepper<Chinese prickly ash group<clove group<blank group,and the total number of bacteria in mixed spice group was significantly lower than that of blank group(P<0.05).When a kind of spices was added,the more spices to be added,the more bacteria to be suppressed within the scope of the experiments;lactic acid bacteria of each group remained on the state of advantage and maintaining a high level in the whole manufacturing proeess,eolony eount was more than that of staphylococcus aureus and yeastt in different periods.Lactic acid bacteria of spice mix group in the whole period is significantly higher than blank group(P<0.05),adding a kind of spices,Lactic acid bacteria of dried intestine clearly higher than the blank group,but not significant(P>0.05).Whena kind of spices was added,within the scope of the experiments,the more spices to be added the more bacteria to be suppressed.Spices inhibited effectively the growth of spoilage organisms and pathogenic bacteria so that the lactic acid bacteria the lactic lacti acid bacteri growed better.Both a kind of spices and spice mix had inhibition on staphylococcus aureus and yeast at the beginning of fermentation of dried sausage,inhibition strength was spice mix>Chinese prickly ash>pepper>cloves,During the process of subsequent processing,spices had a promotion effect on the growth of the two kinds of bacteria,and the more spices was to be added,the more bacteria was to be promoted.In the late stage of processing,the number of staphylococcus aureus and yeast in mixed spice group was significantly higher than that in the blank group(P<0.05),the number of staphylococcus aureus in the pepper group was significantly higher than that of blank group(P<0.05)at the end of the dry period.Above conclusion shows:Either adding a spice or mixed spices had an effect on bacterial flora of air dried sausage,the addition of mixed spices had the greatest influence on the bacterial strain,the second was the pepper.Obviously the addition of spices have inhibited the growth of harmful bacteria and increased the competitive advantage of beneficial bacteria,to ensure the edible security of the dried intestine and shelf-life is great significance.2.The changes of physico-chemical properties of dried fermented sausages in the fermentation cycle were analyzed.The results showed that:in the entire fermentation process,pH value of mixed spice group,peppergroup,Chinese prickly ash group,clove group were lower than that of blank group.And only at the beginning of the fermentation,the pH decreased significantly(p<0.05),after air drying of the dried sausages,the pH value of spices groups dropped below 5.3,the high acid environment is conducive to inhibit the growth of spoilage organisms and pathogenic bacteria.Both the addition of the mixture of spices and the addition of clove powder,Chinese prickly ash,pepper have accelerated the lower rate of moisture content in dried intestine,but the effect was not significant(p>0.05),while adding spices is not the key factors to influencing the moisture content,but still has certain effect on it.3.The volatile flavor compounds in the fermentation cycle at the end of ripening(6d)and the end of the drying time(14d)were measured and analysed by SDE/GC-MS.The contents and results were as follows:The control group,the group mixed spice,elove groups,pericarpium group,pepper group had been respectively detected 46 species,67 kinds,51 kinds of,respectively,56 kinds and 61 kinds of volatile flavor compounds,especially olefins and esters were more than the others.IS-alpha-pinene,IR-alpha-pinene,Camphene,Alpha-piene,Beta-piene,3-carene,D-Limonene.Limonene,Copaene.Myrcene,Caryophylleneoxide.Isoledene,pentadeeane,3-Cyclohexene-1-niethanol,alph...,Linalool,Eugenol were detected in mixed spice group from the spices compounds;IS-alpha-pinene,Beta-piene,3-carene,D-Limonene,Linalool,Eugenol weredetected in clove group from the spices compounds;Myrcene,3-carene,Beta-piene,D-Limonene,Linalool,Isoledene,Alpha-Terpineol,Beta-Terpineol,Eugenol were detected in pericarpium group from the spices compounds;IS-alpha-pinene,Camphene,Beta-piene,3-carene,4-carene,D-Limonene,Copaene,pentadeeane,Linalool,Alpha-Terpineol,Eugenol were detected in pepper group from the spices compounds.The proportionof the volatile flavor compounds from the spices compounds more than 20%.Therefore,spices play an important contribution on the volatile flavor of dried sausages.they are essential flavor source in dried sausages.Spices of each group were detected ethyl esters volatile flavour compounds,such as ethyl caproate,ethyl acetate,palmitic acid,myristic acid ethyl ester,ethyl oleate,linoleic acid ethyl ester,kwai acid ethyl ester,etc,and theirs' contents were far higher than the blank group.We can see from this,adding spices was more conducive to microbial fermentation,promoted alcohols and acids occuring esterification reaction,in turn,generated more esters flavor substances.lt was in conformity with that spices promoted the growth of beneficial bacteria.2-Pentanone which is from Staphylococcus aureus to incomplete beta oxidation of the unsaturated fatty acid,produced by the beta-keto acid decarboxylation was detected in add spices of each group,and increaseed the fruit aroma of fermented sausage.There were alarge number of 3-hydroxy 1-2-butanone generated by the Staphylococcus aureus metabolism of carbohydrate checked out in the group of mixed spice,pepper,clove.They have a extremely significant role in taste.This shows the change of the microbial closely associated with the formation of flavor. |
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