淘米水投加对花生渣厌氧发酵产酸过程的影响

Effect of rice wash on the acidification of anaerobic fermentation from peanut residue

在发酵温度为35℃和原料干物质(TS计)质量固定的条件下,研究了淘米水的投加对花生渣厌氧发酵过程中有机质溶出的影响。试验设置淘米水与花生渣干物质比(TS)分别为1∶0(1#),1∶1(2#),1∶1.5(3#),1∶2(4#),1∶3(5#)和0∶1(6#)共6个处理。试验结果表明:淘米水的投加不能加速花生渣内蛋白质的溶解,且随着TS的升高,蛋白质溶出率及降解率降低;淘米水的投加明显提高了花生渣内碳水化合物的降解速率、挥发酸(VFAs)的产量及酸化率。当TS为1∶2时,4#试验组碳水化合物的降解速率、VFAs浓度及产率最高,分别为0.010/d,14 497.460 mg/L和0.54 g/g(VS),酸化率高达83.4%,产酸量为1#试验组与6#试验组总产量的1.36倍,提高了36.0%。淘米水与花生渣联合发酵以产偶数酸发酵为主导,占其总酸含量的90.0%,且不能通过调节TS配比的方式改变其发酵产酸类型。

On the basis of temperature of 35 ℃ and fixed total solid（TS） of substrates, the effects of dosing rice wash on hydrolysis and acidification of peanut residue were investigated. The experiment set up 6 treatments for rice water and peanut residue, the total solid（TS） ratios were set as 1∶0（1#）, 1∶1（2#）, 1∶1.5（3#）, 1∶2（4#）, 1∶3（5#） and 0∶1（6#）, respectively. The results indicated that the rice wash can not accelerate the dissolution of protein in peanut residue, with the increase of TS ratio, protein dissolution and degradation rate were lower, but rice wash helped to improve the degradation of carbohydrates rate and acidification in peanut residue. The acidification effect was best when the mixing ratio of rice wash to peanut residue was 1 ∶2, with the degradation of carbohydrates rate reached 0.010/d, volatile fatty acids（VFAs） content of 14 497.460 mg/L and the yield was 0.54 g/g.VS, and acidification rate is as high as 83.4%, its produce acid quantity for a single material 1# and 6# 1.36 times of production, increased by 36.0%; The combined fermentation of rice wash and peanut residue is dominated by even acid fermentation, which accounts for up to90.0% of total acid content, and cannot affect the fermentation production acid type by regulating the ratio of TS.