FISHERIES RESEARCH INSTITUTE,MOA,TAIWAN

It is the current development trend of the feed industry to develop functional feeds by adding probiotics, algae or peptides, and other raw materials. In order to ensure the activity of feed additives, the Fisheries Research Institute has developed a oil/water emulsification after coating technology, which uniformly mixes water and oil—the two substances of different polarities—and properly controls the temperature of the post-spray to successfully spray probiotics on the surface of the feed during the mass production process. This not only saves the time of artificial mixing by the farmer but also effectively reduces the loss of additives and makes the probiotics more effective. 

Probiotics have been widely used in the culture industry. Different probiotics have different functions, including assisting in improving the breeding environment, increasing the immunity and disease resistance of breeding organisms, etc. The Fisheries Research Institute has actively developed a series of probiotics, such as lactic acid bacteria and bacillus, which can be used in aquaculture. After such probiotics are added to the feed, they would have the functions of protecting the intestinal health of farmed organisms, strengthening immunity and disease resistance, promoting growth, and increasing survival rate.

Aquatic compound feed is divided into different types, such as powder, pellet, and extruded feed. Traditional powder and pellet feed have shortcomings, such as poor stability in water, fast settling speed, and low feed conversion efficiency. It also tends to cause feed waste, dissolve and lose nutrients or pollute water quality. In contrast, the extruded feed has good stability in the water and can suspend on the water for a long time. It is a high-quality product with low waste, low pollution, high conversion rate, high efficiency, and convenience for feeding management. However, in the manufacturing process of extruded feed, an extruder must first be used to pressurize and knead, and the feed is heated to mature by steam. Therefore, probiotics that are not resistant to high temperature and high pressure usually cannot be added directly in the pelletizing process but are mostly mixed in water at the breeding site to make them attached to the surface of the feed and dry in the shade before feeding. This process is not only time-consuming and labor-intensive, but it also makes the probiotics easy to dissolve and lose the active ingredients.

The oil emulsification after coating technology developed by the Fisheries Research Institute is to cover the feed with oil via negative pressure vacuum-embedding and coating after feed granulation and drying so that the probiotics are successfully sprayed on the surface of the feed, which can greatly save the manual mixing time and effectively reduce the dissolution to ensure the effectiveness of the probiotics. In addition, the oil content of the feed can increase from 15% to more than 25%, improving the post-stage fattening effect of farmed fish. This method can be applied to the addition of probiotics and other heat-sensitive substances susceptible to heat damage, such as enzymes and non-heat-protected vitamins. Their being sprayed on the feed after being emulsified with oil can ensure the retainment of the nutrients and efficacy.

Feed of oil emulsification and spray with probiotics (traditional powder, pellet, and extruded feed)