用酸水解法由橡木宛栲胶渣生产饲料酵母的研究

STUDIES ON THE ACID HYDROLYSIS OF VALONEA EXTRACT RESIDUES FOR FODDER YEAST PRODUCTION

在我国的栲胶工业生产中每年产生废渣 (栲胶渣 )近 13万t之多 ,探索有效的利用途径是很有意义的。本研究涉及用酸水解法由栲胶渣生产饲料酵母的相关问题 ,其主要目的在于阐明所选定的栲胶渣原料是否能有效地适用于稀硫酸高温渗滤水解工艺技术 ,并同时考察其水解糖液对生产饲料酵母的适应性。从 4家栲胶厂采取的 5种栲胶渣样品经分析表明 ,以橡木宛栲胶渣含糖量最高 ,分别可达到 5 6 78%和 5 9 70 % ,故最后将其选定为饲料酵母生产原料。在硫酸浓度为 0 5 %～ 0 8%和温度为 180～ 190℃的条件下水解 6 0min ,得糖率平均可达 40 % ,相当于理论得糖率的6 7% ,接近水解工业生产一般水平。在对中和后水解糖液以热带假丝酵母 (Candidatropicalis)进行发酵时 ,酵母得率可达还原糖含量的 36 71%～ 39 84% ,其蛋白质含量可达 43 6 4%～ 48 6 8% ,亦接近水解工业生产一般水平。研究结果表明 ,橡木宛栲胶渣用酸水解法生产饲料酵母在技术上是基本可行的 ,在经济上与其它水解工业原料生产的产品成本是相近的。

In China,about 130,000 tons of different kinds of extract residues are obtained per annum in the tannin extract industrial production. To find an effective pathway for utilization of this resource has a very important significance.This work is concerned in the production of fodder yeast from tannin extract residues using acid hydrolysis method.Its main purpose is to clarify whether the tannin extract residues as raw material are suitable to the percolation hydrolysis technology at high temperature using dilute sulfuric acid,and meanwhile to investigate the conformability of the hydrolyzate neutralized as substrate for the fodder yeast fermentation.The chemical analytical data of five kinds of tannin extract residues from four manufactories showed that the sugar content of two valonea extract residues is the highest,up to 56.78% and 59.70%, respectively.Therefore these residues were chosen as raw materials in this experiment.When these residues were subjected to hydrolysis for 60 minutes with dilute sulfuric acid from 0.5% to 0.8%,at temperatures from 180 to 190℃,its sugar yields averaged about 40%,corresponding to 67% of the theoretical sugar yields,approximating to the general level of hydrolysis industrial production.When the substrate was fermented with Candida tropicalis ,the yeast yields range from 36.71% to 39.80% of the reducing sugar content,and the protein content of yeast amounts from 43.64% to 48.68%,approximating to the general level of hydrolysis industrial production.Research results revealed that utilization of valonea extract residues for production of fodder yeast is basically feasible by means of acid hydrolysis in respect of technique.The production cost is economically near to that from other kinds of raw material used in hydrolysis industry.