基于近红外光谱与机器学习的萨拉米香肠成熟度判定模型构建OA

In this study,the effects of different starter cultures on the physicochemical quality of salami during ripening were systematically evaluated using near infrared spectroscopy(NIRS)and machine learning(ML)algorithms,and a non-destructive method for determining the key ripening-related physicochemical indexes of salami was established using NIRS and ML.Experimental groups with different mixed starter cultures were set up(combinations of Pediococcus pentosus,Lactobacillus casei,Leuconostoc intestinalis,Staphylococcus xylosus).The physicochemical properties of fermented sausage including pH,moisture content(MC),water activity(aw),color difference(ΔE),and resilience index(RI)were dynamically monitored.Three predictive models were developed using partial least squares regression(PLSR),random forest(RF)and extreme learning machine(ELM)based on the NIRS data.The predictive ability of three data input methods,namely,the full-band data,principal component analysis(PCA)and regression coefficient(RC),was comparatively analyzed.The results showed that 1)the sausage made with the P.pentosus M10+L.casei M13+L.intestinalis+S.xylosus received the highest sensory score with outstanding performance in color,texture,flavor and overall acceptability;2)NIRS allowed the prediction of aw,MC,ΔE and RI,while the prediction accuracy for pH was low(coefficient of determination of prediction set(Rp2)=0.45);3)both feature extraction methods effectively reduced data dimension;the cumulative contribution rate of the first five principal components of PCA was 98.86%,while RC reduced the number of spectral variables from 176 to 10-25;and 4)the PLSR-RC model was the optimal predictive model for aw with Rp2 of 0.92 and mean squared error of prediction(MSEP)of 0.02,the ELM-full band model was the optimal predictive model for MC(Rp2=0.92,MSEP=2.56),and the PLSR-full band model was the optimal predictive model for both ΔE and RI with Rp2 of 0.71 and 0.83,respectively.In summary,the mixed-strain starter can significantly improve the physicochemical quality and sensory characteristics of sausage,and the PLSR model shows the best prediction accuracy and stability in the analysis of NIRS data,providing reliable technical support for the rapid detection of fermented meat maturity.