Comparison on Changes of Volatile Components in Gecko Before and After Processing by HS-SPME-GC-MS / 中国实验方剂学杂志

ABSTRACT

ObjectiveOn the basis of sensory evaluation， the changes of volatile components in gecko before and after processing were compared， and the odor correction effect of different processing methods of gecko was discussed. MethodRaw products， fried yellow products， vinegar processed products， wine processed products， talcum powder scalding products and white wine sprayed products after scalding talcum powder of gecko were prepared， and 10 odor assessors were invited to evaluate the 6 samples in turn by sensory evaluation. Headspace solid-phase microextraction-gas chromatography-mass spectrometry （HS-SPME-GC-MS） and relative odor activity value （ROAV） were used to analyze the key odor components， and multivariate statistical methods were used to analyze the difference of volatile components between raw and processed products of gecko. Taking water-soluble extract and protein contents as internal indicators， sensory evaluation score and content ranking of differential components as external indicators， and assigning a weight of 0.25 to them respectively， the comprehensive scores of raw products and processed products of gecko were calculated to evaluate the odor correction effect of each processing method. ResultThe average sensory evaluation scores of the raw products， fried yellow products， vinegar processed products， wine processed products， talcum powder scalding products and white wine sprayed products after scalding talcum powder of gecko were 1.6， 5.2， 6.2， 6.1， 7.2 and 8.0， respectively. ROAV results showed that key components affecting odor of gecko were 2-ethyl-3，5-dimethylpyrazine， isovaleraldehyde， trimethylamine， 1-octen-3-ol， n-octanal， nonanal， 2-methylnaphthalene， γ-octanolide， 2-heptanone and phenol. Principal component analysis （PCA） significantly distinguished raw products from processed products. Orthogonal partial least squares-discriminant analysis （OPLS-DA） results showed that there were 16， 13， 16， 16， 16 differential components between raw products， fried yellow products， vinegar processed products， wine processed products， talcum powder scalding products and white wine sprayed products after scalding talcum powder of gecko. Among these differential components， there were 4 common components， namely， the contents of different odor components （2-methylnaphthalene and 2-ethyl-p-xylene） decreased， while the contents of different flavor components （2-decanone and 2，3，5-trimethylpyrazine） increased. The comprehensive scoring results showed that the odor correction effect of each processed products was in the order of talcum powder scalding products>wine processed products>vinegar processed products>fried yellow products>white wine sprayed products after scalding talcum powder. ConclusionTalcum powder scalding is a better method to improve the odor of gecko， and it can provide an experimental basis for the processing of gecko to correct the odor.