Ingredients analysis | Evaluation on the value of digestion speed of feed protein ingredient

What’s the significance of study on the digestion speed of protein ingredients?

Improving pig production performance is an effective way to reduce the cost of per kilogram meat and gain benefit. While feed nutrition is the main factor and determines the performance. Protein and energy are the two key nutrients in feed, and their total amount accounts for more than 90% of the whole formula. Studies have shown that only when the digestion and absorption speed of protein and energy are synchronized, can the maximum deposition of the two nutrients be achieved in animals.

Taking the current piglet feed as an example. The energy supply has adopted a typical combination of raw materials with fast (monosaccharide/disaccharide), medium (fast starch), and slow (medium-slow starch and fat) speed of digestion. Thus, the supply of protein should also adopt this rule: raw materials with fast (amino acids and small peptides), medium (medium and long chain peptides) and slow (complete protein) digestion. However, there is no systematic review data on the digestion speed of different protein materials.

Comparative study on the digestion speed of different protein ingredients.

• Study object

6 kinds of common protein ingredients in pig feed: Peru steam fish meal, dehulled soybean meal, soybean protein concentrate, expanded soybean, fermented soybean meal, enzymatic hydrolysate of soybean protein (Chengdu Mytech)

• Method

Using pepsin + trypsin digestion method, Set different digestion time points, collect the digestion fluid to determine the nitrogen content, calculate the protein digestion rate, and draw the protein digestion rate curve.

• Result

The law of in vitro protein digestion rate of different protein ingredients

1. Peruvian steam fish meal: there was no significant difference in digestibility at 30, 60 and 90 min (P>0.05). While digestibility increased significantly at 120 min, 180 min, and 240 min respectively (P<0.05), and there was no significant difference in digestibility after 240 min (P>0.05).

2. Dehulled soybean meal: there was no significant difference in digestibility at 30, 60 and 90 min (P>0.05). Digestibility increased significantly at 120 min and 150 min respectively (P<0.05), and there was no significant difference in digestibility after 210 min (P>0.05).

3. Soy protein concentrate: there was no significant difference in digestibility at 30, 60 and 90 min (P>0.05). Digestibility increased significantly at 120 min and 240 min respectively (P<0.05).

4. Extruded soybean: there was no significant difference in digestibility at 30, 60, 90, 120 and 150 min (P>0.05). Digestibility increased significantly at 210 min (P<0.05), and there was no significant difference in digestibility after 240 min (P>0.05).

5. Fermented soybean meal: there was no significant difference in digestibility at 30, 60, 90 and 120 min(P>0.05). Digestibility increased significantly at 150, 180 and 240 min respectively (P<0.05), and there was no significant difference in digestibility after 240 min (P>0.05).

6. Enzymatic hydrolysate of soybean: there was no significant difference in digestibility at 30 and 60 min (P>0.05). Digestibility increased significantly at 90 min (P<0.05), and there was no significant difference in digestibility after 120 min (P>0.05).

In vitro protein digestibility of different protein ingredients at the same digestion time

• Digestion for 90 min

The digestibility of enzymatic hydrolysate of soybean protein was significantly higher than that of fish meal and dehulled soybean meal (P<0.05). There was no significant difference in the digestibility of fish meal and dehulled soybean meal (P>0.05); the digestibility of soybean protein concentrate, extruded soybean, and fermented soybean meal was significantly lower than that of dehulled soybean meal (P<0.05).

• Digestion for 150 min

There was no significant difference in the digestibility of enzymatic hydrolysate of soybean protein and dehulled soybean meal (P>0.05); the digestibility of fish meal, soybean protein concentrate, expanded soybean, and fermented soybean meal was significantly lower than that of dehulled soybean meal (P<0.05).

• Digestion for 240 min

There was no significant difference in the digestibility of enzymatic hydrolysate of soybean protein, dehulled soybean meal and fish meal (P>0.05).The digestibility of soybean protein concentrate, extruded soybean and fermented soybean meal was significantly lower than that of dehulled soybean meal (P<0.05).

• Digestion for 360 min

There was no significant difference in the digestibility of enzymatic hydrolysate of soybean protein and dehulled soybean meal (P>0.05); the digestibility of fish meal, soybean protein concentrate, extruded soybean and fermented soybean meal was significantly lower than that of dehulled soybean meal (P<0.05).

Discussion

• Different protein ingredients have different digestion speed

1.Enzymatic hydrolysate of soybean protein is digested rapidly in 1-2 hours.

2.Fish meal and dehulled soybean meal are digested at medium speed in 3-4 hours.

3.Soy protein concentrate, extruded soybean, and fermented soybean meal are digested slowly in 5-6 hours.

• The processing technology alters the protein structure, thus the digestion speed is different

1.Enzymatic hydrolysate process (enzymatic hydrolysate of soybean protein) increased the digestion rate and digestibility.

2.Alcohol soaking process (soybean protein concentrate), extruding process (extruded soybean) and fermentation (fermented soybean meal) decreased the digestion speed and digestibility.

Application

It is suggested to combine protein materials with different digestion speed in piglets feed. For example: enzymatic hydrolysate of soybean protein or amino acid (fast digestion) + fish meal or soybean meal (medium speed digestion) + soy protein concentrate or extruded soybean or fermented soybean meal (slow digestion), in combination with energy materials with different digestion speeds, to accelerate the growth rate of piglets and achieve the best performance.