| This thesis was research about the processing method of instant black tea by oxygen. Using green tea infusion as raw material,the research processed instant black tea by oxygen and oxide additives.The satisfaction function method in mathematics was used in the result analysis, the turbidity、luminance and the red degree of the production were proposed synthetic mathematical expectation to replace the comprehensive quality of the production. Based on this, the result of the experiment was optimized by the response surface method in SAS software. The experiment was divided into two parts:At the first part,the research was using green tea infusion as raw material, sodium hydroxide as additives,’Hong Yan’type black tea for model.Infusions pH,reaction temperature,infusions concentration and reaction time were chosen for influence factors. The extraction technology was optimized by central composite design combined with desirability function analysis. The optimum conditions were as following:the Infusions pH was9.5,The infusions concentration was20%, the reaction temperature was80℃and the oxidation time was20min. The brightness was56.3, clarity was7.6NTU, red degree was42.8of the trial production sample,the sensory evaluation was’Hong Yan’.In the second part, the research was using green tea infusion as raw material,’Hong Liang’type black tea for model. Selected a phosphate (sodium hydrogen phosphate), the concentration of sodium hydrogen phosphate、reaction temperature and oxidation time were chosen for influence factors. The extraction technology was optimized by Box-Nebenkern design combined with desirability function analysis. The optimum conditions were as following:the concentration of p sodium hydrogen phosphate was2.75g, the reaction temperature was80℃,and the oxidation time was30min,while the purity of the hydrogen was more than95%. The brightness was32.5, clarity was7.6NTU, red degree was34.2of the trial production sample,the sensory evaluation was’Hong Liang’. |
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