The Analysis And Application Of Amino Acids In Honey

Honey is rich in several kinds of nutrients,such as phenolic acids,flavonoids,vitamin,amino acids,protein,mineral and so on.It is raw material for food and drug with great potentiality.Flower origin is one of the key factors for honey qualities,meanwhile,the geographic source,the method of collection and processing and storage condition could affect honey qualities as well.Therefore,accurate and reliable methods need be established,which could be used to identify honey flower origin and control process.It is the key to improvement in honey quality.Amino acids,a group of nutrients of honey mainly from pollen,could be used to identify honey floral origin.Amino acid are reactants of maillard reaction and amino acid contents would change during heat treatment.So the change of amino acids could monitor honey processing.This thesis select 5 types honey(jujube honey,chaste honey,lungan honey,acacia honey and rape honey)as study subjects according to its color,geographic source and market price.This thesis analyzed the free amino acid contents and amino acid contents through acidic hydrolysis of proteins.The floral origin of honey were identified through amino acid contents combined with chemometrics methods.In addition,the change of amino acid contents during heat treatment were studied.The thesis included five parts,and the contents as follow:1.This study was conducted to determine amino acid contents from honey by high performance liquid chromatography,amino acids were derivatived by waters AQC kit.The results showed that the differences of some amino acid contents were large for different honey types,such as proline,phenylalanine,etc.Amino acid contents combined with chemometrics method were used to identified honey floral origin in this thesis and obtained a ideal result.2.Protein in honey was determined with coomassie brilliant blue and electrophoresis methods.The results showed that protein contents and constituents of different honey type were distinctly different,such as the proteins electrophorograms of jujube honey has a specific protein at 17KDa.Based on the difference of honey protein,this thesis analyzed amino acid contents through hydrolysis of proteins.Ultrafiltration and acidic hydrolysis were used in this thesis.Amino acid contents through hydrolysis of proteins combined with chemometrics method were used to identified honey floral origin in this thesis.The results showed that 5 type honeys could be correctly classified,but the distance between chaste and rape honey were shorter.Classification result was not better than the free amino acid classification.3.Jujube and chaste honey were selected as study subjects,since these honey had higher amino acid contents.These honey were heated treatment.The color value,5-HMF content and amino acid contents were analyzed during heated treatment.These data combined with chemometrics method could classify honey according to these processing degree.Therefore,the best processing temperature was 45 ?,heating time should be no more than 8h at 65 ?,and honey should avoid heat treatment at 80 ?.And the chaste honey were affected more than jujube honey during heating processing.