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Product Description

Acid Protease AP-520 is a food grade acid protease enzyme produced from robust strains of Aspergillus niger using submerged fermentation, extraction, and refining techniques. AP-520 can effectively hydrolyze proteins under acidic conditions.
AP-520 can be used in the production of potable alcohol, food and beverage where protein hydrolysis is needed under low pH conditions.
Product Characteristics
Declared Enzyme:        Acid Protease
EC No.: EC
Activity: 100,000 U/ml (minimum)
Appearance: Black Brown Liquid
Product pH: 2.5∼5.0
Specific gravity: ≤1.25 g/ml


Effect of pH
The effective pH range for the activity of AP-520 is approximately 2.0 to 6.0, with an optimum performance at pH 2.5 to 3.5.
Effect of Temperature
AP-520 works at temperatures from 30 to 65°C with it optimal temperature range from 40 to 50°C.
Effect of Metal ions
AP-520 is activated by Mn2+, Ca2+ and Mg2+ ions. Heavy metal ions such as Cu2+, Hg2+ and Al3+ will inhibitthe enzyme activity of AP-520.
In intermittent fermentations, the entire dose of AP-520 should be added all at once after the fermentation tank is filled approximately 30%. In continuous fermentations, AP-520 should be added continually, with the dosage rate dependent on the amount of mash fed at the inlet of the fermentation tank.
Use of AP-520 in fermentation process offers the following benefits:
  • Promote raw material particles to be dissolved
    AP-520 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 and reproduction of yeast 
    Free amino nitrogen (FAN) is the most effective nitrogen source for yeast. Adding AP-520 during alcoholic fermentation can effectively hydrolyze proteins and peptides in the 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 alcohol, 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-520 is an ideal nutrient for yeast growth and accelerator for fermentation.
Dosage Guidelines
Recommended dosage of AP-520 is 0.001 to 0.015% w/w (dry solids basis). Actual dosage should be depending on the raw materials and process of production.
AP-520 is packaged in 25kg, 30kg food-grade HDPE drums or 1125kg IBC totes. Customized packaging is available upon request.
Storage & Shelf-life 
  • AP-520 has been formulated for optimal stability.
  • Typical shelf-life is twelve months if this product is stored at 0∼ 25°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.
Safe Handling of Enzymes
Inhalation of enzyme dust and mists should be avoided. In case of contact with the skin or eyes, promptly rinse with water for at least 15 minutes. For detailed handling information, please refer to the Material Safety Data Sheet.

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