Analysis And Quality Evaluation Of Polyphenols Composition Of Blueberry Honey In Guizhou

Blueberry honey is a natural mature honey brewed by bees from the nectar of blueberries.It has a sweet taste and unique flavor,and is deeply popular by consumers.This dissertation intends to analyze the composition of the polyphenolic compounds,the sensory properties,physicochemical properties,antioxidant activity of Guizhou native blueberry honey as well as explore its volatile components.This will make the foundation of identification and commercialization of Guizhou specific blueberry honey.The detailed results are as follows:?1?Amberlite XAD-2 macroporous resin was used for enrichment and extraction of polyphenols in blueberry honey with an average extraction rate of 90.07%.18polyphenolic compounds were identified from the extracts by LC-MS/MS including 6phenolic acids:protocatechuic acid,p-hydroxybenzoic acid,vanillic acid,caffeic acid,and paraffin Soybean acid;12 flavonoids:ferulic acid,rutin,myricetin,luteolin,mulberry pigment,quercetin,apigenin,naringenin,kaempferol,isorhamnetin,aspenin,pinusin And galangin.The content of p-hydroxybenzoic acid?74.08?197.56?g/100g?,quercetin?37.96?146.77?g/100 g?,kaempferol?46.67?76.04?g/100 g?in blueberry honey is relatively high,which is potential testing index for the polyphenol identification of blueberry honey.?2?The sensory evaluation scores of blueberry honey were significantly different?p<0.05?,among which the score of honeybee from western honeybee was the highest,with the advantages of lighter color and delicate crystal;The blueberry honey form eastern honeybee has the lowest score,which is characterized by coarse particles and peculiar smell.The total acidity of blueberry honey is 36.24?46.81 meq/kg,and the ratio of glucose and moisture content is above 1.7,meaning blueberry honeybee has the characteristics of high acidity and easy crystallization;The total phenolic acid and total flavonoids of blueberry honey are 20.61?24.72 mg GAE/100 g and 3.31?6.77mg RE/100 g respectively;IC₅₀concentration for DPPH free radical scavenging rate and IC₅₀concentration for ABTS free radical scavenging rate are 117.02?157.01mg/m L and 139.41?269.06 mg/m L respectively.And the higher the total phenolic acid content,the higher the ability to scavenge DPPH free radical and ABTS free radical.?3?The electronic nose and GC-MS were used to study and analyze the volatile components of blueberry honey,honey of various flowers,vetch honey,fennel honey and gall nut honey.The results show that the volatile components of different honey sources have significant differences.The electronic nose can quickly distinguish the volatile components of different honey sources effectively;GC-MS has detected 103volatile components,including 18 kinds of aldehydes,15 kinds of ketones,7 kinds of acids,15 kinds of esters,9 kinds of alkanes,6 kinds of alcohols,10 kinds of benzene and phenols,14 kinds of olefins and other nine substance.Cluster analysis can distinguish different kinds of honey effectively.In addition,2-hydroxybenzaldehyde is only detected in blueberry honey,which can be used as a tseting indicator of volatile components for blueberry honey.