Mechanism of action of acidulant: reduce the acidity and gastrointestinal pH of the feed system, and improve the activity of digestive enzymes

The food source of piglets before weaning is mainly breast milk, which contains a large amount of lactose, which is converted into lactic acid by lactobacillus in the stomach, so that the pH in the stomach is maintained at 4.0, and milk protein can be better digested. Due to the imperfect development of the digestive system and immune organs in the early weaning of piglets, the secretion of digestive enzymes and gastric acid is insufficient, and the piglets suddenly change from sucking breast milk to eating solid feed, the lactose supply is reduced, and the lactic acid production in the stomach is reduced, while the solid feed system has high acidity and strong ability to neutralize acid, so that the pH in the stomach > 5.5. A large number of tests have shown that the optimal pH required by pepsin is 2.0~3.5, and when the pH > 4.0, the activity of pepsin is weakened or even inactivated. The high pH environment at weaning can lead to poor protein digestion, so the addition of acidifiers to the diet of weaned piglets will reduce the acidity of the feed system, reduce the pH in the gastrointestinal tract, further improve the activity of pepsin, promote protein digestion, and the amount of feed digestion will also increase accordingly.

Early weaned piglets, due to the imperfect development of their digestive system and immune system, through exogenous addition of acidifiers, the use of its acidification can activate pepsinogen, stimulate the secretion of pepsin, and then improve the digestibility of feed gastric protein. A large number of studies have confirmed that the addition of acidifiers to piglet diets can reduce dietary pH and gastrointestinal pH and increase the activity of digestive enzymes. Jing Cui et al. found that the addition of acidifiers to the diet of weaned piglets had a significant effect on the pH of gastric and duodenal contents (P<0.05), and a decreasing trend on the pH of contents in the jejunum and ileum, but the difference was not significant (P>0.05), and there was no significant effect on the pH of colonic contents (P>0.05).