Studies On Component Dissolution Variation And Stability Of Red Bayberry Integrated Alcoholic Beverages

Red bayberry(Myrica rubra) integrated alcoholic beverages on current market are mostly soaking liquor, tranditionally loved by residents in Jiangsu and Zhejiang Provinces. As a liqueur wine, it combines both the bouquet flavor of based wine and the fruity smell, and preserves to the greatest degree the nutrients in red bayberry. There are 18 species of red bayberry identified through the provincial agencies at present. Different varieties of red bayberry differ in nutrients as well as their taste. In this paper, red bayberry integrated alcoholic beverages was produced by immersing the fresh fruits in alcohol solution. Two leading varieties in Zhejiang producing area, namely Biqi and Dongkui, were used as raw material. Different concentrations of alcohol of food grade and the ratios of solid-liquid (m: v), i.e. fruit to alcohol solution, for making the liqueur wine were studied. Ultrasonic treatment was used to assistant the dissolution of ingredients in the fruit to alcohol solution during the immersion process. The ingredients dissolved were dynamically monitored and optimized immersing conditions were investigated. At the same time, red bayberry integrated alcoholic beverages was prepared with these two species as raw material and commercially available liquor as base liquor. Clarification processing and color stability study were carried on after storing the alcoholic beverages for three months. The study aims to provide some technological and theorical basis on the extraction process and clarification of red bayberry integrated alcoholic beverages, stability of anthocyanins and application of some co-pigments. The main results of this paper are as follows:(1) Solid-liquid ratio and alcohol concentration affected the concentration of dissolved constituents in red bayberry liqueur wine. The higher the concentration of alcohol, the greater concentration of ingredients in the liqueur wine. During the extraction process, concentration of dissolved constituents presented a downward trend after the first rise, among which, anthocyanins concentration decreased to the largest degree. Total acid and TSS kept in little fluctuation after the first rise.(2) Solid-liquid ratio (m/v), alcohol concentration, ultrasonic time and immersing time were used as four factors in three levels in an orthogonal experiment to optimize the extraction conditions. The results indicated that the optimum extraction conditions for the two species were different. The optimum extraction conditions of the liqueur made by Biqi were solid-liquid ratio 1.5,60% alcohol, ultrasonic time 40 min, and extraction days 30 d, Under this condition, the liqueur’DPPH clearance rate was 88.5% and the color a* value was 60.93. The optimum extraction conditions of the liqueur made by Dongkui were solid-liquid ratio of 1:1,60% alcohol, ultrasonic time 50 min, extraction days 40 d, and the liqueur’s DPPH clearance rate was 56.4% with its a* value 48.69.(3) Different concentrations of gelatin, PVPP, chitosan, and chitosan-xanthan gum were used to clarify the liqueur. Clarity and color values indicated that they all played an effective role in clarifying. Optimum clarification methods were determined using changes of main composition in the liqueur wine and its stability as an index. The results showed that the gelatin clarification group got the highest clarity while stability in liqueur clarified by PVPP was the worst. The two clarifying agents——chitosan and chitosan-xanthan gum had less effect on the composition of liqueur, however, chitosan-xanthan gum group has some precipitation during storage, so the optimal clarification agent was chitosan with an addition in 0.3 g/L.(4) Biqi variety was used to investigate anthocyanins’ stablity in red bayberry integrated alcoholic beverages. It was found that there was a preferable linear relation between-ln(Ct/C0) and time t after heat treatment, with its regression coefficient R2 greater than 0.84. The result indicated that thermal degradation of anthocyanins corresponded to the first order kinetics equation. According to the changed form of Arrhenius equation lnk=lnKo-Eo/RT, apparent activation energy of anthocyanin E0 during thermal degradation was determined as 7.23×104kJ/mol. The loss of anthocyanins caused by ultraviolet irradiation was slower than that caused by heat (95 ℃) with its loss rate 20% after irradiation for 10 h.(5) In this experiment the best co-pigment was proved to be natural pigment, of which mulberry red pigment was the best, followed by red bayberry pigment, with the color preservation rate increasing from 64.5% to 91.5%. To reduce the addition of pigment, red bayberry juice could be used to add into the liqueur in the late flavor adjustment, not only to enhance the fruity smell of the liqueur, but also to improve the stability of anthocyanins and color.