Acid Protease AP-100 is produced from selected strains of Aspergillus niger through submerged fermentation and extraction and refining processes. It can catalyze protein hydrolysis under acidic conditions and is applicable to hydrolysis of proteins with acidic medium.
AP-100 is applied to the production of ethanol.
Declared Enzyme: Acid Protease
Systematic Name: EC 220.127.116.11
Activity: 100,000 U/ml (minimum)
Appearance: Black Brown Liquid
Product pH: 2.5 to 5.0
Specific gravity: ≤ 1.25 g/ml
EFFECT OF pH
AP-100 can work at pH range from 2.0 to 6.0. For maximum activity, the optimal pH is 2.5 to 3.5.
EFFECT OF TEMPERATURE
AP-100 can work at temperatures from 30 to 65°C, with its optimal temperature from 40 to 50°C.
EFFECT OF METAL IONS
AP-100 is activated by Mn2+, Ca2+ and Mg2+, and inhibited by Cu2+, Hg2+ and Al3+.
Use of AP-100 in fermentation process offers the following benefits:
Promote raw material particles dissolved
AP-100 can hydrolyze the proteins of the raw materials, thus destroy the interstitial cell wall structure of starch granules, so as to release the starch wrapped in the granules, which is conducive to saccharification.
Promote the growth of yeast
Free amino nitrogen (FAN) is the most effective nitrogen source for yeast. Adding AP-100 during alcoholic fermentation can effectively hydrolyze proteins and peptides in raw materials so as to generate FAN that yeasts can absorb, thus promote the growth of yeasts, increase the quantities of yeasts in the fermented mash, and shorten the fermentation cycle.
Beneficial to high concentration fermentation
In high concentration fermentation of ethanol, it is mainly nutritional deficiencies rather than the accumulation of alcohol that leads to the decrease of fermentation activity. Free amino acids (FAN) can not only shorten the fermentation cycle but also increase the output of alcohol, improve ethanol tolerance and survival rate of yeasts. Therefore, AP-100 is an ideal nutrient for yeast growth and accelerator for fermentation.
In intermittent fermentation, it should be added at one time when the fermentation tank is filled with one third materials. In continuous fermentation, it should be added consecutively depending on the amount of saccharification mash fed at the inlet of fermentation tank.
Recommended dosage of AP-100 is 0.001 to 0.015% w/w (dry solids basis). Actual dosage should be depending on the raw materials and process of production.
STORAGE & SHELF-LIFE
Typical shelf-life is six months if this product is stored at 0∼10°C in its original packaging, sealed and unopened, protected from the sunlight. Prolonged storage and/or adverse conditions such as higher temperatures may lead to a higher dosage requirement, thus should be avoided.