Research On The Deacidification Technology Of The Hawthorn Juice

Hawthorn is rich in a variety of nutrition and medicinal compounds, so it's regarded as "edible medicinal fruit". However, because hawthorn fruit contains large amount of acid, the consumer market of fresh hawthorn and its products was greatly limited. Therefore, the lack of the practical and effective deacidification technology for the hawthorn juice become the principal problem in the hawthorn -processing industry. On the basis of development haw-processing industry, the objective of this research was to find a deacidification technology by chemical deacidification technology, resin deacidification technology and microbial deacidification technology, which applie to reduce acid and retain the flavonoids in hawthorn juice. The deacidification process of hawthorn juice was investigaged using the modern chemistry and instrumental analysis methods, the method of microbial screening and separation, modern fermentation technology. The mainly results obtained from this study are as follows:1. Based on the analyze data of chrominance. pH and acid of hawthorn juice, the chemical deacidification was gained.the results showed that the acid of hawthorn juice be reduced 43.59%by adding 5.2 g/L total volume of CaCO3 and KHCO3(1:2) on the condition of 30?,80r/min for 2h.2. Through the comparison of the static adsorption of acid and flavonoids, weak alkali ion exchange resin (D311) is the most suitable for reducing organic acids of the hawthorn juice. The best conditions for reducing organic acids are:Room temperature,100 ml/h velocity.The optimization regeneration condition of D311 is in the low flow down 100 ml 1 mol/1 NaOH. After much regeneration, the total acid adsorption ability has reduced 11.5%, the flavonoids adsorption ability has reduced 73.3% and the flavonoids retention ratio can amount to 88.8%.3. The microorganism that has been highly efficiency degradated citric acid was gained through microbial qualitative screening technology. This microorganism can effectivly degradate citric acid in hawthorn juice, but has less effect on hawthorn flavonoids. The microorganism belong to candida species, and named J3 by the morphological, physiological and biochemical, and the sequence analysisl8 SrDNA. The concentration of citric acid in the culture solution reduced from 20 g/1 to 4.2 g/1 when cultivate the J3 yeast for 72 h under the conditions of 30?,150 r/min and 40 ml/250 ml triangular flask.90 mg/L SO2,4% alcohol and 80 g/L of citric acid can all not inhibition the growth of J3 yeast.4. The carbon metabolism of J3 yeast and medium organic acids composition are markedly differences under different amount of sugar in culture conditions, The J3 yeast can priorly utilize sugar when the culture condition of sugar is higher (?8g/l). The organic acids composition of the HPLC analysis results indicated that the J3 yeast utilize exogenous citric acid, and accompanies with accumulation of apple acid and oxalic acid. Meanwhile, the citrate metabolism by J3 yeast may lead to the rise of the glyoxalic acid. The J3 yeast citric acid mainly metabolize through the glyoxylate cycle by analysing the metabolic pathways in each key enzymes. The hawthorn juice acidity can reduce from 11.4g/l to 3.4g/l by mixed culture fermentation between the J3 yeast and the acid wine yeast.