| This study is a part of the item entitles"Study principium and quality of flavor of traditional meat". The aim is to keep Jinhua ham's special and character flavor, while to reduce salt content, producing cycle, and reduce producing cost. The new type ham flavoring is produced by addition exogenous enzyme. The main content and results are as follows.The effects of exogenous proteases and lipases on flavor of Jinhua ham flavoring were studied. Tastes component and precursors were quickly produced by addition exogenous proteases and lipases. Optimum conditions were 6% of salt content, 0.15g/kg of nitrite content, cured 30h at the temperature of 4, the dose of neutral lipase 621u and neutral proteases 5375u, hydrolysable time 4 hours at the temperature of 43.40 by single factor experiment and surface response analysis. There were free fatty acids 2.50% and amic nitrogen 2.40% of the hydrolysable solution in the optimum condition. The main free fatty acids from fresh meat to the end of hydrolyzation were palmitic, oleic, stearic, linoleic, their content incessantly accumulated; The rate of break outing from lipids was stearic> palmitic> linoleic> oleic during the whole processing; oleic and linoleic were oxidation during the end of processing, their content changed from 1.64%,0.83% to 1.22%,0.60%. Saturated fatty acid content didn't change. Taste was good and aroma was weak in the the hydrolysable solution by sensory evaluation.Study on changes of physico-chemical characters and flavor of the same oxidation condition for different hydrolysates in order to find relation between hydrolyzation and oxidation and acceptive degree. The results showed TBA value and carbonyl value were always most and lied on proportion of different pro-flavor for different hydrolysates in the oxidation time. However TBA value and carbonyl value showed raise trend during oxidation process. pH value firstly descended and raised, and showed ruleless change for different hydrolysates in the oxidation time. Difference of pH value was small and water content showed ruleless change in the oxidation time. Hydrolysate of FFA 0.95%~1.02% and AJTD 2.07%~2.30% oxygenated 8~12 days. Hydrolysate of FFA 1.17 %~1.22% and AJTD 2.63%~2.89% oxygenated 8 days. Flavor assessed raise with FFA and AJTD increased in the oxidation time. Flavor assessed descended with FFA and AJTD exceeding 1.17%, 2.89%.Relation between oxidation and flavor was studied for the taste and aroma by single factor experiment and surface response analysis. The optimum conditions were: soybean lipoxygenase 30u, reaction temperature 34℃, oxidation times 8 days; or no soybean lipoxygenase, reaction temperature 34℃, oxidation times 8 days. Flavoring was better.Changes in the optimum conditions were studied. Protein and lipase were brook down, and their content changed from 56.05%, 15.58% to 38.12%, and 7.68%. The effects of addition of protease and lipase on proteolysis, lipolysis were 3.27% amido-nitrogen and 5.69% FFA. Amido-nitrogen went up to 3.76% and FFA declined to 4.55% during oxidation times. Chance range was 0.49% and 1.13%. The acid value (AV), carbonyl value volatile electropositive nitrogen rised, their content got to 8.35mg/g,1.27meq/kg and 49mg/100g. POV, TBA value and microbe went up and down, their content got to 2.51mep/kg,0.08mg/100g and 2.9×104个. Water content and pH went down to 53.10% and 5.44.Ham flavoring were compare to Jinhua ham by analyzing flavor composition of ham flavoring by GC-MS and sensory evaluation. The results showed accepting of Ham flavoring is good but aroma is weak. The GC-MS flavor profile analysis objectively proved that the Ham flavoring flavor profile was consistent with that of raw ham. There were mostly flavor and unique flavor of Jinhua ham, and the content was consistent with that of raw ham in the ham flavor.
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