Control of key points in the high-quality trace element premix feed production

At present, the supply mode of trace elements is still dominated by inorganic trace elements, mainly because of its low price and long-term use, which has formed an inherent habit. However, most of the feed-grade inorganic trace elements come from industrial by-products. Because of their low prices, upstream companies do not adequately handle them, and a large amount of toxic and harmful substances are likely to remain, which brings many problems to feed safety and stability.

These problems are only slightly alleviated with the use of organic trace elements. This is mainly due to the intensified competition of feed plants, the higher requirements for feed quality, and the demand for animal appearance traits in the breeding terminal. In the past two years, driven by large feed factories, organic trace elements have gradually been recognized and widely used. In this environment, new problems have arisen as the times require. How to scientifically evaluate and rationally apply organic trace elements has brought new problems to many feed formulators.

Under the pressure of the above-mentioned double problems, more and more feed companies have chosen to directly hand over the premix of trace elements, similar to the multi-dimensional model, and hand it over to professional trace element production and processing companies to focus their energy on The part that I am best at. There are seven or eight kinds of trace elements, dozens of inorganic and organic monomer raw materials in the feed. If the feed enterprise evaluates one by one, it will inevitably increase a large amount of human and financial input. Failure to evaluate will increase the risk of feed safety and stability.

Under this trouble, custom-made compound trace elements are the most effective and safest solution. According to the different needs of different customers, we adopt a personalized customization method and hand over all the trace element premixes to professional suppliers. The benefits of customized composite trace elements can be briefly summarized in the following aspects: ①Reduce the risk of corporate purchases. In the past, more than a dozen types were purchased, but now only one or a few types of compound minerals need to be purchased. ②Reduce the pressure of storage and warehouse. In the past, dozens of trace monomers needed to be stored separately, which not only occupied the raw material warehouse, but also the long-term storage of inorganic minerals is prone to oxidation, discoloration, agglomeration and moisture absorption. Switching to composite mines can eliminate such problems. ③Reduce a lot of investment in quality control personnel and equipment.

So, how can we produce high-quality premix of trace elements? Need to do the following aspects of raw material control, formula control, premix feed production line process and premix feed equipment and quality control.

1. Control of raw materials

For the control of trace element premix raw materials, three principles are mainly grasped, namely: control of oxidation factor, control of caking factor and control of hygiene index.

(1) Control of oxidation factor

As we all know, the most prone to discoloration in the microelement premix is ​​iron. The light green ferrous ions in the raw materials are oxidized into yellow ferric ions, which causes the premix to change color. So, what causes the oxidation of iron ions, and how do we control this discoloration factor. Briefly summarized into three aspects. First, the control of oxidants in feed. Feed-grade trace elements mostly come from industrial by-products. The production of feed-grade zinc sulphate is mostly made by wet method. The raw material used is zinc hypoxide from industry, which also contains other elements such as cadmium, lead, arsenic and iron. Therefore, in order to obtain high-content zinc sulfate products, impurity removal is required. In the impurity removal process, oxidant removal occupies an important position.

The oxidant used for these impurity removal is mostly hydrogen peroxide, and a part of it is brought into the trace element premix with the zinc sulfate raw material, so the divalent iron in the trace element premix is ​​oxidized to trivalent iron.Second, the choice of carrier. Many companies use stone powder as the carrier of the trace element premix. As the pH of the premix increases due to the stone powder, ferrous iron will be oxidized to ferric ions when the pH is greater than 5. Third, the selected organic iron is not sufficiently chelated, and is oxidized to trivalent iron in a large amount under the action of free water in the premix. The method to solve the above problems is very simple. First, detect the residual amount of oxidant in each batch of raw materials. Second, select appropriate trace element carriers. Third, scientifically and effectively evaluate organic trace elements.

(2) Control of caking factor

The agglomeration of the premix is ​​mainly caused by the moisture absorption and recrystallization of the raw materials. The main reason for this phenomenon is that a large amount of free water, free acids and chlorides remain in the raw materials. The main methods to control agglomeration are as follows: First, strictly formulate corporate standards. Because the relevant national standards for trace element monomers control fewer indicators, they cannot rely on the national standards to select a high-quality raw material. It requires companies to meet their own needs and testing. Strength to formulate detailed corporate internal control standards. Second, strictly control whether the above three of all raw materials exceed the internal control standards of the enterprise. Third, minimize the use of copper sulfate pentahydrate.

(3) Control of health indicators

On the basis of the national standard, the content of nickel and mercury needs to be additionally controlled, because nickel directly affects the skin coloration of young animals and poultry, and copper sulfate has the highest content of nickel. Mercury easily damages the gastric mucosa and intestinal villi, leading to digestibility and absorption rate decline, so weaned piglet diets need to focus on controlling whether mercury exceeds the standard. Another important issue is the control of dioxins. Most of the raw materials for the production of feed-grade copper sulfate in our country use waste corrosion liquid from the production of circuit boards. The waste corrosion liquid used to produce circuit boards just has the three conditions for generating dioxins, namely: benzene ring, chloride ion and high temperature. Therefore, we tested the content of dioxins in the finished feed grade copper sulfate which exceeded the EU standard by 3 to 5 times. As we all know, dioxins are highly carcinogenic, and long-term use of high copper in piglet feed is bound to cause harm to the environment and humans.

2. Control of formula

Due to the low absorption rate of inorganic trace elements and the low price, the cost of compound feed is very small. Therefore, manufacturers have been using inorganic trace elements in a proportion that exceeds the NRC and national standards by 3 times or even higher. As we all know, there is a certain safety threshold for the use of trace elements, and there is also a certain proportion of absorption between the elements. Due to our large-scale use, animals cannot fully absorb it, resulting in a great waste of trace elements. At the same time, a large number of cations also cause a certain stimulus to the animal intestinal electrolyte balance. Therefore, for the use of trace elements, we must focus on the two basic principles of effective content and the ratio of elements, and design animal trace element premixes of different varieties and stages with ideal trace element models.

When designing any animal's trace element premix, the following factors must be considered on the basis of formula design principles: First, the loss caused by the redox reaction between different forms of trace elements. Second, the best addition ratio among the four elements of iron, copper, zinc and manganese. Third, the ratio of organic trace elements to inorganic trace elements. Fourth, whether different regions are in the lack of trace elements. Fifth, in different seasons, the safe amount of trace elements needs to be increased. Among them, the addition ratio of inorganic trace elements and organic trace elements is the most perplexing problem encountered by many feed companies in the design process. Here, the basic trace element application database and market application experience value owned by our production enterprises are extra important.

3. Premix Feed Manufacturing Process, equipment and quality control

(1) Production process

First of all, we must be clear about the characteristics of high-quality trace element premixes, which can be summarized in five points. That is: First, make the micro-components evenly distributed. Second, improve the instability of trace components. Third, the level of addition can be standardized. Fourth, reduce the production process of feed enterprises. Fifth, to maximize the synergistic effect of trace components.

It can be seen from the above that uniform distribution ranks first, so how to make chemical substances with different bulk density, different moisture, and different particle sizes to be mixed uniformly, there is no doubt that there are two aspects, namely: ultra-fine pulverization of very small components of raw materials, and automatic Scientific application of pre-mixing equipment.

According to the principle of Poisson distribution, the premix product with a mixing uniformity (CV) <3% or less is required. At least 900 particles of this component in each sample can prevent errors in nutrient supply and analysis results of this component. For example, sodium selenite, calcium iodate, and organic chromium in the premix of trace elements have very low levels of addition, and the effective dose is close to the toxic dose. Therefore, ultrafine pulverization is necessary to make the mixing uniform. At present, premix feed making plants all use dry ball milling for crushing. The average particle size after crushing is 500-600 mesh.

(2) Premix feed production equipment

The scientific use of fully automatic pre-mixing equipment greatly improves production efficiency and reduces raw material procurement costs for feed factories. It also strictly controls the safety and stability of the trace element premix. The central control system controls the feeding sequence of the raw materials in the formula to reduce the problems of multiple feeding and missed feeding due to manual feeding. Accurate micro-weighing can effectively control the feeding error of materials. The double paddle mixer machine can ensure that the uniformity of the material mixing is controlled below 3%.

(3) Precise quality control and visual traceability

In addition to scientific technology and sophisticated automatic premixing equipment, there must also be a set of refined quality control processes and traceability systems. The first is the determination of the mixing uniformity. The traditional determination of the mixing uniformity of the trace element premix is ​​to detect the iron element in it. However, there are two problems in the detection of iron element. First, the proportion of iron element in the micro-ore is relatively large. , Can not fully reflect the uniformity of the multi-ore mixing. Second, the micro-ores prepared by some premix feed processing plants currently do not contain iron, so it is impossible to detect the iron to reflect the uniformity of the premix feed product. You can choose trace components such as iodine, selenium, and cobalt to judge the mixing uniformity index, which is more accurate.

The most important aspect of the current use of trace element premixes is to place the trust of feed companies on the brand of selected multi-mineral suppliers. As a multi-mining producer itself, it is necessary to develop a detailed traceability system so that multi-mining is not a cold product placed in the customer’s warehouse, and the person in charge of the feed company must truly perceive this product. The real situation of every link from raw material procurement, formula design, pre-mixing processing, finished product testing, logistics. To this end, some companies in the market have also launched a product online traceability query system, so that customers can clearly understand the ins and outs of their products.