Organic acids refer to some organic compounds with acidity. The most common organic acid is carboxylic acid, which is acidic from carboxyl group. Calcium methoxide, acetic acid and are all organic acids. Organic acids can react with alcohols to form esters.
Role of organic acids in aquatic products:
1. Alleviate the toxicity of heavy metals, convert molecular ammonia in aquaculture water, and reduce the toxicity of toxic ammonia.
2. Organic acid can remove oil pollution. There is oil film in the breeding pond, so organic acid can be used.
3. Organic acids can regulate the pH of water body and balance the water body.
4. It can reduce the viscosity of water body, decompose organic matter through flocculation and complexation, and improve the surface tension of water body.
5. Organic acids contain a large number of surfactants, which can complex heavy metals, quickly detoxify, reduce the surface tension in the water body, quickly dissolve the oxygen in the air in the water, improve the oxygenation capacity in the water body, and control the floating head.
Misunderstanding of using organic acids:
1. When the nitrite in the pond exceeds the standard, the use of organic acid will reduce the pH and increase the toxicity of nitrite.
2. It cannot be used with sodium thiosulfate. Sodium thiosulfate reacts with acid to produce sulfur dioxide and elemental sulfur, which will poison breeding varieties.
3. It cannot be used with sodium humate. Sodium humate is weakly alkaline. The effect will be greatly reduced if they are used.
Factors affecting the application of organic acids:
1. Addition amount: when the same organic acid is added to the feed of aquatic animals, but the mass concentration is different, the effect is also different. There were differences in weight gain rate, growth rate, feed utilization rate and protein efficiency; The addition amount of organic acid is within a certain range. With the increase of the addition amount, it will promote the growth of cultured varieties, but if it exceeds a certain range, too high or too low will inhibit the growth of cultured varieties and reduce the utilization of feed, and the most suitable addition amount of organic acid to different aquatic animals will be different.
2. Addition period: the effect of adding organic acids in different growth stages of aquatic animals is different. Studies have shown that it has the best growth promoting effect in childhood, with the highest weight gain rate of 24.8%. In adulthood, it has obvious effects in other aspects, such as anti immune stress.
3. Other ingredients in feed: organic acids have synergistic effect with other ingredients in feed. The protein and fat contained in the feed have high buffering power, which can improve the acidity of the feed, reduce the buffering power of the feed, facilitate absorption and metabolism, and affect the food intake and digestion.
4. External conditions: for the best effect of organic acids, it is also important to have appropriate water temperature, diversity and population structure of other phytoplankton species in the water environment, high-quality feed, well-developed and disease-free fish fry, and reasonable stocking density.
5. Potassium dicarboxylate: adding potassium dicarboxylate can reduce the addition amount and better achieve the purpose.