Shrimp Feed Formulation and Manufacturing Process

The quality of shrimp feed determines the development of shrimp grounds. Shrimp feed cost accounts for about 50% of the overall cost in shrimp fishery! Due to the information is site-specific and proprietary, it is not an easy thing to provide shrimp production cost data. In accordance with one review of hatchery operating costs, we summarized a sketchy production cost data:

Typically, shrimp feed expenses represented at least 40 percent of total nursery production costs. Investment costs for grow-out facilities have been cited as ranging from USD 400/ha (yielding 600 kg/ha/yr) in India to nearly USD 64,000/ha (yielding 2,270 kg/ha/yr) in the USA. Similarly, grow-out operating costs from less than USD 2 to more than USD 15 kg/yr have been cited. The average cost split was 30 percent feeding, 20 percent seed, 15 percent labour and 35 percent other expenses.

What should shrimp farmers do to improve the return on the feed investment?
• Industry education – farmer
– What to look for in a feed
– How to feed
• Improve feeding methods
– Deliver feed to meet nutrient requirements
• Increase cost effectiveness of feeds

– Refine nutrient requirements
– Reduce the use of exotic ingredients
– Stop over formulation
– Manufacture extruded shrimp feed pellets rather than hard pellets

Classification of Shrimp Feed Pellets

At present, there are 2 kinds of feed pellets on the market, hard shrimp feed pellets and extruded food pellets.

Pros and cons of hard pellets

Commercial hard shrimp feed pellets are mainly produced by ring die pellet mill. In the production process, after raw material being crushed and mixed, the starch gelatinized and the protein denaturation in steam conditioning functions, thus the viscous force enhance, then material close to each other under the action of die and roller pressing, rubbing, finally forming through the die hole.

The advantages of hard shrimp feed pellets:

1.The feed formula could be optimized combination to achieve both meet the nutritional needs and reduce the cost;
2.In the process of tempering granulation, feeds are ripened under the effect of steam and loop die, which is conducive to shrimp digestion and absorption.
3.In the granulator suppression effect, all components are bonded with each other, improving the density of the feed, the obtained product are sinking, it is adapt to the shrimp benthic lifestyle.
4.According to the need to add nutrients and medicine, enhance physical fitness and immunity of shrimp.
5.Simple feeding, the shape and size of bait is suitable for shrimp eating.
6.The feed is convenient for preservation and transportation, less affected by the natural conditions, can be produced in large quantities.

But there is a disadvantage of the hard particles shrimp feed, if the starch gelatinization degree is low in production process, the product will have poor water resistance.

Increasing demand on extruded shrimp feed pellets in the near future

With the increase of the shrimps farming scale, the yield of shrimp feed also continued to increase, many livestock feed processing plant and some traditional aquatic feed processing plants have turned to the produce shrimp feed. However, the quality of shrimp feed requirements are relatively high. If only in accordance with the traditional production process of aquatic feed, it is difficult to achieve the quality requirements of shrimp feed, especially in water resistance. With the improvement of living standards, the food quality and safety problems are payed more and more attention. The security problem of shrimp food must start from the source. Therefore, the shrimp culture has to be developed healthy and pollution-free aquaculture. Can not use a lot of antibiotics in feed, one of difficult problem is using ripener to prevent disease. Shrimp feed is a key factor affecting the shrimp culture, have to developing the direction of safety and environmental protection. In the production process of hard pellet feed, if the starch gelatinization degree is low in production process, the product will have poor water resistance. While the requirements of shrimp feed on the water resistance is relatively high, so it is very important to improve the water resistance of shrimp feed. During process the change of various factors will effect quality of feed, especially water resistance. Study on the influence of various factors on the sinking and water resistance of the final product from the feed processing, it can provide technical guidance for the actual production process, so as to improve the process conditions and the quality of the shrimp feed, it is also conducive to promoting the healthy and sustainable development of shrimp aquaculture, improve breeding efficiency. Compared with the hard pellets, the biggest difference with extrusion feed is that material directly into the extrusion machine after quenching and tempering , high temperature high pressure made by rubbing, shearing and heating, then suddenly released into the normal temperature and pressure through the die hole, so as the material formed and produced a series of changes in the physical and chemical properties. During extrusion process the high-intensity hydrothermal can remove most of the harmful factors, improving the safety of shrimp feed. Therefore, shrimp feed produced by fish feed extrusion granulating machine will occupy the heavier market share.

Shrimp Feed Formulation Directly Affecting Quality of Feed Pellets

High-quality shrimp feed is characterized by good water stability, good hygienic control on raw materials for optimum FCR and health of prawn, good attractability and feed palatability, and rich in nutrition to produce healthy and strong prawns. In recent years, pond-reared shrimp develops rapidly. While farmers know little about the shrimp feed production and feeding method. Some of them don’t care about what kind of shrimp feed they are feeding their prawn, while others take no notice of the dose rate, thereby increasing shrimp feed costs increasing, production efficiency reducing. Shrimp feed pellets should be formulated to meet the shrimp’s nutritional requirements of essential amino acids, fatty acids, vitamins, minerals and moulting accelerating substances. To solve those problems, Fanway Fish Feed Machinery introduces some shrimp feed formulas, and hope they will help farmers earn more profits.

Adult fresh water shrimp feed formulation

◇ Formulation of raw materials

◇ Premix formula (g)

◇ Vitamins and mineral elements
Vitamins: (IUs=international units)

Mineral elements(mg./kg):

Macrobrachium nipponense feed formulation

Macrobrachium nipponense is one kind of freshwater shrimp with high economic value and large cultivation potential. It is rich in nutrition, and grows fast, deeply loved by people. Macrobrachium nipponense culture has been popularized in large areas till now.
◇ Adult shrimp feed formulation (%)

◇ juvenile prawn feed formulation (%)

Shrimp Feed Manufacturing Process

A. Grinding technology
The raw material grinding is a basic process, particle size should be above 40-60 mesh. Research shows that the digestion and absorption rate of protein in peanut oil-cake powder that pass the sieve with 40 – 100 mesh have no obvious difference. Considering from the processing energy consumption, The energy consumption of the hammer mill in 100 mesh is the three times higher than that in 40 mesh. Therefore, the fineness of raw material could be not less than 40 mesh, but finer the grinding degree is, better the water resistance of shrimp feed pellets is. In addition, the fine material can improve the mixing uniformity of ingredients and the compaction quality of pellet feed, and it is easy for digestive enzymes to contact with feed to promote digestion. Grinding raw material needs two processes, the first is coarse grinding, like peanut cake and shrimp head capsule. Fish Feed Hammer Mill is needed. It should be equipped with a 3mm sieve piece to crush raw materials into coarse powder. The second process is fine crushing, need Droplet Fish Feed Crusher with sieve of 0.5mm pore. Crushing degree must reach the requirement that all pass 40 mesh, 80% material pass 60 mesh.

B. Batching technology
The raw materials must be cleaned up before crushing, cleaning our debris, such as paper, wood, stones and others. Before the second process, the ingredient, like peanut oil-cake powder, fish meal, spray-dried blood cells, squid powder, should be mixed in accordance with the proportion of ingredients, then crushed into more than 40 mesh powder, then stir well with the standard flour and additive-the coefficient of variation is not more than 10%.

C. Granulation technology
After being crushed, the moisture content of raw materials is 13 %, which makes it not easy to soften up and gelatinize, so it is an important condition to add appropriate amount of water to ensure powder bonding and starch gelatinization. At first, in mixing process, shrimp feed manufacturer should squirt water with high-pressure hydraulic pump to keep the moisture content of raw materials remain about 18%, followed by adding steam. By this means, raw materials are with uniform moisture content and reach softening requirement. After adding steam, the material temperature increases rapidly, extending the material gelatinization time. Only starch fully gelatinized, does the working temperature of dies decrease and the service life of die improve. When raw material temperature, after steam treatment, reaches 90 – 105oC, it is the right time to process the materials. Fish Feed Extruder is used to manufacture delicious and nutritional shrimp feed pellets.

D. Drying technology
The particles come from the host having high moisture content, need to be dried, the most commonly fish feed pellet drying equipment is net Mesh-belt type fish feed dryer. Its role is to reduce the water content, water content is usually below 10%, this can ensure the feed won’t deterioration for more than 2 months; The second role is promoting gelatinization, ripening, and adhesion. General drying temperature is 90oC for 20 minutes, if beyond this standard, the feed may be burned and the vitamin be destroyed, which can affect shrimp’s appetite and the feed prices, while the steam drying temperature can relatively increase to 105oC.

E. Cooling technology
Shrimp feed pellet cooling is usually in the Counter-flow type fish feed cooler, in this progress cool air will take away some hot energy and water, pellet can be packaged when they stay at room temperature. If pellet take cooling progress without drying, a large number of small cracks will appear on the surface and extends to the deep due to the internal of pellet have rapid cooling and dewatering, even good gelatinization fines will also have the phenomenon. In the feeding, the particles will along the crack decomposed into several pieces because of being soaked in water, but the phenomenon will reduce a lot if after drying. The water content is 17% – 18% from feed extruder, 12％—13％after drying, 10% – 11% after cooling.

F. Classifying Screener
After granulating, drying and cooling, unfinished products, including particles, powder and residue, should be screened by classifying screener. Powder and pieces are filtered out from the bottom of machine. Large particles and residue are screened from the top of this machine. Finished materials are packaged in feed column from interlayer. Shrimp feed is classified into four types from juvenile prawn to adult shrimp. Since nutritional ingredient is different, there are different feed size and length. Little shrimp needs feed 0.3-1.5mm in diameter; prawn, 2mm; adult shrimp, 2.7mm. With the growth of little shrimp, the length of granules increases to a few centimetres. In this way, to keep tidy, pure and beautiful, the interlayer of classifying screener can be changed accordingly. The raw materials should be crushed, screened and packaged once or twice.

G. Packaging
Taking Penaeus Orientalis for example, the feed is stored and fed in shrimp ponds along the coast, easy to be affected by damp because of the humid coastal air, so penaeus orientalis feed pellets must be packaged by paper and plastic syntactic bags. Weight of per package is better to be 20 kg or 25 kg, which is beneficial to transport.