Study On Physicochemical Properties And Stability Of ?-carotene Emulsion Of Peach Gums Based On Different Sources

In order to clarify the processing characteristics and encapsulation effect of peach gums from different sources,13 cultivars of peach gums from 3 geographical origins were taken as the research object in this paper to explore the influence of color and total phenolic contents of peach gums during the process of soaking and drying.Chemometrics were applied to describe the difference of peach gum based on cultivars and geographical origins.Taking tween-20 as reference,three typical cultivars as objects,and the encapsulated properties of emulsions were investigated.It provided theoretical basis for the further application of peach gums in the food field.The main conclusions of the experiment were as follows:(1)The water absorption of peach gum could reach up to 26 times of its original weight.The average content of total phenol in unsoaked peach gum was 2.49 times than that of the sample after soaking.The average content of total phenol in the sample after vacuum freeze-drying under different ratios was 1.14 times than that of the sample after heat pump drying.The average content of total phenol in the unsoaked peach gum under the same drying method was about 2 times than that of the sample after soaking.There was a significant color difference(P<0.05)between the soaked sample and the unsoaked sample,moreover,the color saturation,brightness and b*value were significantly increased(P<0.05).Besides,the color difference of the sample after vacuum freeze-drying was lower than that of the sample after heat pump drying.The results of correlation analysis showed that the total phenolic content was positively correlated with L*value(P<0.01),and negatively correlated with?E value(P<0.05).(2)Main components and processing properties in peach gums were investigated.Total phenolic contents(TPC),amino acids contents,minerals contents and a*for 13 peach gum samples had significant difference(P<0.05).There were 7 principle components in peach gums including threonine(PC1),alanine(PC1),a*(PC2),total sugar contents(PC3),magnesium(PC4),iron(PC5),cystine(PC6),xylose(PC7),respectively.In addition,the distribution of peach gum samples with cultivars and geographical origins separated well regarding amino acids contents and minerals contents as basis.Association models between apparent attributes and physicochemical components demonstrated significant relationships(P<0.05).Amino acids,minerals and soluble protein had an influence on transparency(T)of peach gum samples and viscosity(?)was mainly associated with the structure of PGP.TPC and minerals contents could have an influence on the color of peach gums.(3)Taking tween-20 as control,three varieties of peach gums such as Mixture cultivar(MC),Zhonghpan 11#(ZP11)and Yingqing(YQG),were selected as emulsifier to prepare the encapsulated emulsion and explore physicochemical stability during storage.The results showed that initially,the sphericity and distribution of microcapsules with PGP as emulsifier were better,and emulsion efficiencies(EE)of four emulsions were 82.73%(MC),71.92%(YQG),89.08%(ZP11)and 84.55%(TW-20),respectively.And three emulsions of PGP about D₅₀,D[4,3],D[3,2]were larger.Absolute values of zeta-potential about the three emulsions were higher than 30 m V,among which YQG was the highest.Besides,three PGP emulsions were brighter and had higher saturation in color.After 35 days for storage,absolute values of zeta-potential of three emulsions were still higher than 30 m V(TW-20was 24.52 m V),indicating that the stability of PGP emulsions were better than that of TW-20.L*,a*,b*,C*and h°values of four emulsions increased,demonstrating that the ability of color retention about three emulsions was stronger than TW-20,and the order of the ability was MC>ZP11>YQG>TW-20.Emulsion of YQG was the one with the highest RR(43.44%)after 35 days for storage.