The Study On Optimization Of The Preparation Technology Of Black Garlic And Physicochemical Properties Of ?-cyclodextrin Inclusion Compound

Garlic was used as raw material to prepare black garlic at 60?,70? and 80?.The effects of processing temperature on functional components,processing time and sensory qualities were investigated.The results showed that reducing sugar and total phenol were degraded seriously at 80? for 45 d,the poor nutrient components were obtained at 60? for 80 d,and the best qualities of black garlic belonged to 70? for 60 d.On the basis of constant temperature fermentation,black garlic was prepared by pretreatment and variable temperature fermentation.The effects of refrigeration and water bath pretreatment(RBP),refrigeration and microwave pretreatment(RMP)on nutritional components of black garlic were studied.The results indicated that the contents of reducing sugar and total phenol and amino nitrogen(AN)in black garlic were all increasing under the RBP and RMP,which were higher than those of unpretreated black garlic.Preprocessing combined with variable temperature fermentation was applied to improve the quality of black garlic and shorten the processing time.It was found that high quality black garlic was obtained under variable temperature fermentation for 15 d.In order to study the dehydration mechanism of black garlic,the kinetic characteristics of thin layer drying for black garlic under hot air(HA)and microwave(MW)were analyzed and five mathematical models were used for nonlinear fitting.The results demonstrated that effects of HA temperature and MW power on moisture ratio(MR),drying rate(DR),volume shrinkage,shape change,surface temperature and drying time were significant.The maximum R2(0.99805 and 0.99972)were obtained by fitting the Wang and Singh model and Logarithmic model to the moisture ratio curves under HA and MW drying,respectively.Compared with HA drying,MW drying had higher effective moisture diffusivity(Deff)and lower activation energy(Ea).In order to increase the stability and bioactivity of black garlic powder,the preparation technology,stability,solubility and antioxidant properties of ?-cyclodextrin(?-CD)combined with black garlic powder inclusion compound were researched,optimizing the process parameters by response surface method.The results indicated that the inclusion ratio reached up to 76.92%for the optimized inclusion compound,which had stronger resistance to high temperature,humidity and oxygen,better solubility,DPPH free radical scavenging ability and reducing power.