Characteristic Components Identifiction And Authenticity Evaluation Of Four Monofloral Honeys

The major components in honey is carbohydrates,whereas phenolics may be responsible for functional activity with small amount.It is important to identify the phenolics in honey for their functional activity research.In addition,phenolics in plants varies according to the plant species.Therefore,it is important to indentify the phenolics in monofloral honey,and to evaluate the traceability and authenticity.The aim of the present study was to indentified phenolics of four kinds of monofloral honey,acacia honey,linden honey,vitex honey and rapeseed honey,and evaluates the authenticity of commercial honey.The phenolics in honey were pre-concentration by solid phase extraction(SPE),and the phenolics were identified by LC-MS,GC-MS and NMR.We first indentified phaseate acid and trans,teans-abcisic acid in acacia honey.phaseate acid may be the representative compound in acacia honey.Furthermore,we indentified 4-(2-hydroxypropan-2-yl)cyclohexa-1,3-diene-1-carboxylic acid)in linden honey,it also may be the representative compound,we neamed it lindenin.In vitex honey,we indentified the representative compound 7-O-?-Dglucopyranosyl-dihydroquercetin-3-O-?-Dglucopyranoside.We named it vitexin.In rapeseed honey,we identified the representative compound methyl syringate.We qualitative and quantitative analysis phenolics in 30 acacia honey samples,55 linden honey samples,15 vitex honey samples and 10 rapeseed honey samples.The content of phaseate acid in acacia honey reached 68.01?g/100 g.The average content of lindenin in linden honey was 2.283mg/100g(Tilia mandshurica Rup et Maxim)and 1.564mg/100g(Tilia amurensis Rupr)respectively.The average content of vitexin is 2.5mg/100 g in vitex honey,and the average content of methyl syringate is 1.044mg/100 g in rapeseed honey.Furthermore,Chromatographic fingerprints of four kinds of monofloral honey samples were established.According to the chromatographic fingerprint and the content of the representative compounds,we finally determine the authenticity evaluation index of the four commercial monofloral honey honey.Moreover,according to authenticity evaluation indicator,25 commercial acacia honey samples,24 commercial linden honey samples,13 commercial vitex honey samples and 4 commercial rapeseed honey samples were evaluated for authenticity.Our result indicates that the quality of the four-commercial honey in the market was uneven.The quality of acacia honey is the most serious.Only 3 of the 25 acacia honey samples are real honey.The other 22 brands of acacia honey have different forms of quality problems,including the dilution of honey with syrup,mixed with other monofloral honey or Pure syrup instead of honey.The quality of linden honey is much better than that of acacia honey.14 of the 24 brands belong to the true linden honey,and 3 brands are not linden honey.Five of the 13 vitex honey samples belong to the true vitex honey,and the four brands are not vitex honey.Two of the four rapeseed samples belonged to pure rapeseed honey,and one brand was pure syrup.