Study On A Method For Evaluating The Activity Of Sucrose Invertase In Honey

Honey is one of the most important products in bee industry and has been paid more and more attention because it contains a variety of beneficial bioactive components.However,in order to obtain high profits,some honey production enterprises concentrated the immature honey by heat processing or concealed the shelf life,which is not only affecting the quality of honey,but also the consumer benefits.The activity of enzymes in honey was gradually decreased due to the degree of heat processing and storage time.Therefore,the freshness and quality of honey can be evaluated by measuring the enzyme activity in honey.At present,more and more countries in the world have put the determination of sucrose invertase activity in honey as important as the determination of amylase activity.But up to now,there is no standard method to detect sucrose invertase activity in honey in China.In this sduty,we selected five kinds of honey including Acacia honey,Linden honey,Vitex honey,Longan honey and Litchi honey as research objects.The existence of sucrose invertase in five kinds of honey were verified by the operation of SDS-polyacrylamide gel electrophoresis(SDS-PAGE),non-denatured polyacrylamide gel electrophoresis(Native-PAGE)and liquid chromatography-mass spectrometry(LC-MS).The results also showed that the molecular weights and protein sequences,respectively.Based on the principle that 3,5 dinitrosalicylic acid can be reduced to brown red amino compounds,a accurate method for the determination and calculation of sucrose invertase in honey is established.The optimum reaction conditions of sucrose invertase were determined.Finally,a total of 200 honey samples including raw honey and commercial honey were evaluated for sucrose invertase value by the established method.The results showed that the average level of enzyme values in commercial honey were all lower than that in raw honey.And the level of enzyme values among different brands of commercial honey were quite different.Based on the determination results of sucrose invertase activity in commercial honey samples,the recommended criteria were determined.