Guangxi Le Jiao Acid-free Fermentation Complex Enzyme

Experiment Scheme

The bacteriostasis experiment of acid-free fermentation complex enzyme (hereinafter referred to as complex enzyme) is carried out through mass production operation. The experiment is divided into two experimental schemes: the saccharification tank adjusts PH value and the saccharification tank does not adjust PH value.

I. The experiment scheme where the saccharification tank adjusts PH value in mass production

I.1 Introduction to production operation of fermentation section

1. 75g of complex enzyme is added to each seed tank in the experiment group. After full tank cultivation, 206 and 210 seed tanks are pressed into fermentation tank 211 (experiment group); 207 and 208 seed tanks are pressed into 218 (penicillin group).

2. 650g of complex enzyme is added into fermentation tank 211 and 650g of complex enzyme is added to 212 when tank 211 and tank 212 are connected. By analogy, the sequence of tank connecting is 211-212-213-214. Similarly, the sequence of tank connecting of fermentation tank 218 is 218-217-216-215, except that penicillin is normally added into 218 row.

3. Carry out one batch with the existing production process, and detect acidity, volatile aide in liquefaction stage, acidity and volatile acid in fermentation start, acidity and volatile acid in 20h, 40h and 60h and the whole sample in the end as contrast data.

1.2 Experiment results 

1.3 Result analysis

1. As indicated by laboratory results, the data of the three groups of contrast experiments are similar, which means that the effect of complex enzyme during the period is relatively stable without strong fluctuation.

2. By comparing complex enzyme addition and penicillin addition, there is few difference between the experiment data, which manifests that the complex enzyme can restrain bacteria effectively. Tank discharging acidity is about 4.5 and the acid rise stays within 1. Volatile acid is approximately 0.2 within 70 hours after tank discharging. All of the above are at the normal level.

II. The experiment scheme where the saccharification tank does not adjust PH value in mass production

1.1 Introduction to production operation of fermentation section

1. During fermentation stage, 650g of complex enzyme is added into fermentation tank.

2. Four seed tanks are used in fermentation section, numbered 206, 207, 208, 210. And the experiment fermentation tanks are numbered as 222, 223, 224, 225, 226, 227, with volumes all being 130 m3.

3. 650g of complex enzyme is added into fermentation tank 222 and 650g of complex enzyme is added into 223 when 222 and 223 are being connected. By analogy, the sequence of tank connecting is 222-223-224. Similarly, the tank connecting sequence of fermentation tank 227 is 227-226-225, except that penicillin is normally added into 227.

Explanation: According to the existing process, acid-free feeding is basically realized in 223 and 224 experiment tanks and other tanks will have feed liquid with PH adjusted.

4. Carry out one batch with the existing process. Detect acidity, volatile aid in the liquefaction stage. Detect acidity, volatile acid at the beginning of fermentation and the whole sample in the end as contrast group data.

1.2 Experiment results 

1.3 Result analysis

1. From the experiment results, it can be seen that the acidity increase is less than 1 and there is no sharp increase in acidity.

2. According to the existing process, acid-free feeding is basically realized in 223/224 experiment tanks, which manifest that the effect of complex enzyme is obvious when the acid rise is stable within 1 and volatile acid is about 0.15;

3. The volatile acid in other experiment tanks is relatively high, which may due to the change of raw materials in the blending section. Comprehensive analysis shows that bacteria growth can still be inhibited within 80 hours, and spore growth may be prolonged to adapt to fermentation environment and carry out metabolism and acid production. By adjusting PH to restrain miscellaneous bacteria, volatile acid increase significantly after 70 hours. From the effect, adding complex enzyme is better than adjusting PH to inhibit bacteria. In other indexes, the acid rise is less than 1, the alcohol degree is about 9 and the reducing sugar, total sugar as well as appearance sugar are almost the same as before. The results show that the complex enzyme can restrain bacteria.

III. Conclusion

1. According to the results of the two experiment schemes, it can be seen that the effect of complex enzyme is relatively stable and it can restrain bacteria. As shown by the experiments, the complex enzyme can completely replace and adjust PH to restrain bacteria growth.

2. Based on the existing process, the utilization of nitric acid is 40-45kg/t, equivalent to 32-36yuan/t alcohol. The use of penicillin is 16g/t, equivalent to 2 yuan/t alcohol. The unit price of the complex enzyme is 480,000/t, equivalent to 31-35yuan/t alcohol, and the cost is the same as a whole. In addition, by reducing the amount of acid added, the corrosion to equipment has been subconsciously reduced. Moreover, by detecting the increase of nitrogen content in fermentation tank after adding nitric acid, some strains may be metabolized by nitric acid. The alcohol yield may be raised by decreasing the amount of nitric acid added. Bu cutting down nitrate concentration in sewage, the purity and gas volume biogas produced by sewage will increase correspondingly. It is difficult to estimate the accurate increase in output.

Zhongrong Technology Corporation Ltd.

Zhang Dongming  

No. 1, Changqian Road, Fengrun District, Tangshan City, Hebei Province

2017-07-18