Analysis of volatile compounds of Tremella aurantialba fermentation via electronic nose and HS‐SPME‐GC‐MS

Abstract

AbstractTo detect the odor changes of the volatile compounds during the Tremella aurantialba (T. aurantialba) fermentation associated with its degree, electronic nose (E‐nose) technique, and headspace solid phase microextraction combined with gas chromatography‐mass spectrometry (HS‐SPME‐GC‐MS) analyses were performed each day. E‐nose and GC‐MS were used to recognize the comprehensive aroma characterization and volatile compounds of T. aurantialba fermentation, respectively. Principal component analysis (PCA) were used to analyze the data detected by E‐nose technique and GC‐MS. Support vector machine (SVM) was established to analyze E‐nose date for predicting the different stage of the T. aurantialba fermentation. The main volatile compounds were identified by GC‐MS analysis as alcohols, esters, aldehydes, ketones, heterocyclic, and aromatic compounds. The results of PCA by E‐nose were more similar with that of GC‐MS. The discrimination rates of the SVM model were 100 and 97.14% in the training and testing sets. It can be concluded that E‐nose technique coupled with SVM classification tool has high potential to monitor the fermentation process. These may sufficiently demonstrate excellent promise for the E‐nose technique and GC‐MS method to be applied in the liquid state industry.Practical applicationsE‐nose combined with GC‐MS could detect the odor changes of the volatile compounds during the T. aurantialba fermentation. Both analytical techniques showed good performances in the classification of the fermentation degree of T. aurantialba. These may provide a theoretical basis for the design of the portable electronic nose, which would achieve the real‐time smell monitoring of liquid state fermentation of T. aurantialba associated with its degree of fermentation. This equipment can be used to determine the state of fermentation instead of workers. The E‐nose technique and HS‐SPME‐GC‐MS method could be applied in the liquid state fermentation industry in the future.