Analysis of Aroma Components of Alternative Tea for Acacia Robinia Pseudoacacia Flowers in Different Processing Techniques

To explore the different characteristics of the main aroma components of locust flower substitute tea with different processing techniques,the fresh Robinia pseudoacacia L. flower were used to produce substitute tea by five processing technologies with sun-dried green tea,baked green tea,fried green tea,white tea and black tea. The volatile compounds of Robinia pseudoacacia L. flower substitute teas were identified by headspace solid-phase microextraction combined with gas chromatography-mass spectrometry. The relative odor activity value(ROAV)was used to evaluate the contribution of aroma components to the overall flavor of Robinia pseudoacacia L. flower substitute teas to identify the key odor compounds. The results showed that seventy-five volatile constituents with a sense of smell were detected from the Robinia pseudoacacia L. flower substitute teas including alkenes,aromatic hydrocarbons,alcohols,aldehydes,ketones,acids,phenols,esters,lactones,nitrogenous compounds and miscellaneous oxygen compounds. The main compounds were aldehydes(16 species),alcohols(12 species),alkenes(11 species)and esters(10 species). There were 13 species common compounds which were styrene,2-pentylfuran,5-isopropyl-2-methylphenol,limonene,benzyl alcohol,phenylacetaldehyde,phenethyl alcohol,decanal,beta-cyclocitral,2-phenylcrotonaldehyde,methyl anthranilate,D-longifolene and ethyl palmitate. The common key odor compounds were decanal and limonene. Five different processing technologies were used to substitute locust flower tea with different main aroma components. Among the key odor compounds under different process conditions,linalool,(E,E)-2,4-nonadienal,and(E)-2-nonenal are unique aroma substances in the tanning process. Naphthalene is a unique aroma substance in the baking process. 2-Methylbutyraldehyde is a unique aroma substance in the roasting process. 1-Octen-3-ol is a unique aroma substance in the fermentation process.