| The single factor experiment and orthogonal experiment were used to optimize processing technology of low acidity Sichuan-style salami which was inoculated Lactobacillus planetarium and Pediococcus pentosaceus and Staphylococcus in this project. Four kinds of Sichuan-style sausage were produced under different processing conditions, which were named A(controlling temperature and humidity and inoculation) and B(controlling temperature and humidity but no starter cultures) and C(inoculation but in natural condition) and D(the natural conditions and not inoculation). The characteristics of sensory quality, fundamental physical and chemical character, lipolysis and lipid oxidation, protein degradation, microorganisms were analyzed. The major results and conclusions were as follows:(1) The optimum production conditions of low acidity Sichuan-style salami for the fermentation period:fermentation temperature 20 "C, fermentation time 12h, glucose 0.10%, relative humidity 75%; for ripening period:ripening temperature 13℃, ripening time 4d and relative humidity 60%.(2) The pH value, Aw, water content, residues of NaNO2 of the group A were lower than the other groups(P<0.05), which were 5.50、0.740、28.80%、4.42mg/kg respectively at the end of drying, which indicated that low acidity was in favour of the moisture loss and inoculated starter cultures can promote NaNO2 degraded.(3) The content of acid value(AV), peroxide value(POV) and TBA value had an upward trend. The acid value of group A was 2.701mgKOH/g, which was higher than the others(.P<0.01).The POV value and TBA value of group A were 0.783meq/kg and 0.252mgMDA/kg, which was lower than the others(P<0.01). The saturated fatty acids of group A was 1.48 times as many as raw meat, meanwhile, the monounsaturated fatty acids of group A was 1.68 times as many as raw meat. The content of SFA and MUFA were higher than the others, which indicated that low acidity could enhanced the activity of fat hydrolysis enzyme which could promote fat to hydrolyze free fatty acid and inoculated starter cultures could slow down oxidation of free fatty acids, delay it rancidity.(4) The total volatile basic nitrogen and non-protein nitrogen content of four groups showed an upward trend. The content of NPN was highest, which indicated that low acidity and inoculated starter cultures could promote protein degradation. The content of TVB-N of group A was lower than group B, which indicated that nitrogen-containing substances less and the rancidity was lighter. The content of all free amino acid of group A was 605.06mg/100g, which was higher than the others(.P <0.01). The degree of protein degradation was most(P<0.05), which indicated low acidity could lead to protein denaturation and accelate protein degradation.(5) A total of 80 volatile components were found in four kinds of Sichuan-style sausage and hydrocarbons, esters and alcohols were intended to be the mainly flavor substances. The kinds of esters, acids and hydrocarbons were more than others in group A, meanwhile, The relative content of esters, alcohols and aldehydes were 22.16%,21.29% and 14.26%, which were higher than others(P<0.01).(6) The sensory score was 92, which was the highest in all groups, which indicated that inoculated starter cultures could improve the sensory quality of sausage. The result showed that the Sichuan-style sausage which were processed by controlling temperature and humidity and the traditional fermented Sichuan-style sausage could be distinguished effectively by using electronic nose, four kinds of Sichuan-style sausage which were produced under different processing conditions could be distinguished effectively by using electronic tongue. |
PDF Full Text Request