CN102669729A - Loach processing technology - Google Patents

Abstract

The invention relates to a process for treating loach, the steps of which are as follows: the water content of loach is reduced to less than 5% by drying or vacuum freeze-drying to make dried loach; the dried loach is put into a supercritical extraction device for extraction Degreasing treatment is carried out in the kettle; the extraction parameters are as follows: the fluid is supercritical CO ₂ , the flow rate is 15-30L/h, the extraction pressure is 22-35MPa, the extraction temperature is 30-50°C, the separation pressure is 10-16MPa, and the separation temperature is 50-60°C , the treatment time is 0.5-1.5h; after degreasing treatment, degreasing dried loach and loach fish oil are obtained. The process of the present invention adopts the supercritical fluid treatment method to effectively remove the fish oil in the dried loach, so that the dried loach can avoid oxidation and can be stored for a long time, and the dried loach after treatment can be better crushed to make loach powder. And the by-product is high-quality loach fish oil. It can also significantly reduce the microbial content in the loach powder, making the subsequent loach powder safer.

Description

A kind of processing technology of loach

technical field

The invention relates to a food processing method, in particular to a loach processing technology .

Background technique

Traditional Chinese medicine believes that loach meat or the whole body can be used as medicine, which has medicinal effects such as nourishing yin and clearing heat, invigorating spleen and Qi, dispelling dampness, and invigorating yang, which are recorded in "Compendium of Materia Medica" and "Dictionary of Chinese Medicine". Among the folk remedies, there is also a method of eating loach to reduce fire. The in-depth study of modern biology shows that the natural polysaccharides, glycoproteins and polypeptides extracted from loach have anti-inflammatory, transaminase-lowering, jaundice-removing and liver-protecting effects through animal experiments. At present, the products developed by utilizing the health care and medicinal effects of loach mainly include loach powder. The processing method of existing loach powder mainly adopts the method of drying or vacuum freeze-drying to remove the moisture in the loach to become dried loach, and then pulverizes and processes into loach powder. Because loach contains a certain amount of fat, the mass percentage of fat in dried loach is about 4% to 6% after the water is dried. If it is not removed during processing, it will easily cause loach powder to form agglomerates in the subsequent crushing process. , so that the crushing particle size cannot be very fine. The analysis of scientific researchers shows that loach fat contains more than 50% unsaturated fatty acids. If the storage conditions are improper, it is easy to be oxidized, resulting in a rancid smell of dried loach or loach powder, which seriously affects the shelf life of the product. Simultaneously, the unsaturated fatty acid in the loach fat contains rich DHA, EPA and other health-care components, and if the extraction and separation are carried out, the loach resources can be fully utilized.

The existing methods for separating fish oil from aquatic products mainly include heating and solvent methods, but the high extraction temperature of the heating method will affect the medicinal efficacy of dried loach, and the solvent method will cause solvent residues in loach powder and fish oil, which will affect the product. the quality of. How to effectively remove the fat of loach during processing without affecting the medicinal efficacy of loach, and at the same time make full use of its fish oil, there is no suitable solution in the prior art.

Contents of the invention

The technical problem to be solved by the present invention is to provide a loach treatment process with a more reasonable process, which can avoid the oxidation of dried loach, prolong the storage time and produce loach fish oil by-product.

The technical problem to be solved by the present invention is achieved through the following technical solutions. The present invention is a kind of processing technology of loach, it is characterized in that, its step is as follows:

(1) The water content of the loach is reduced to less than 5% by drying or vacuum freeze-drying to make dried loach;

(2) Put the dried loach into the extraction kettle of the supercritical extraction device for degreasing treatment; the extraction parameters are as follows: the fluid is supercritical CO ₂ , the flow rate is 15-30L/h, the extraction pressure is 22-35MPa, and the extraction temperature is 30-50 ℃, separation pressure 10MPa～16MPa, separation temperature 50℃～60℃, treatment time 0.5～1.5h;

(3) After degreasing treatment, degreasing dried loach and loach fish oil are obtained.

In the processing technical scheme of loach of the present invention, further preferred technical scheme or technical feature are as follows:

1. In step (1): drying until the water content of the loach is preferably 4%.

2. Before the degreasing treatment, the dried loach can also be cut into sections, and cut into sections of dried loach with a length of 3 to 4 cm.

3. In step (2), the preferred extraction parameters are as follows: CO ₂ flow rate is 20L/h, extraction pressure is 25MPa, extraction temperature is 40°C, separation pressure is 14MPa, separation temperature is 55°C, and treatment time is 1 h.

Compared with the prior art, the process of the present invention adopts the method of supercritical fluid treatment to effectively remove the fish oil in the dried loach, so that the dried loach can avoid oxidation and can be preserved for a long time, and the dried loach after the treatment can be better preserved. Pulverize to make loach powder, and obtain high-quality loach fish oil as a by-product, which can be further processed and utilized. Through the treatment of the process of the invention, the microbial content in the loach powder can also be significantly reduced, so that the subsequently prepared loach powder is safer.

Detailed ways

The specific technical solutions of the present invention are further described below, so that those skilled in the art can further understand the present invention, without limiting their rights.

Embodiment 1, a kind of processing technology of loach, its step is as follows:

(1) The water content of the loach is reduced to less than 5% by drying or vacuum freeze-drying to make dried loach;

(2) Put the dried loach into the extraction kettle of the supercritical extraction device for degreasing treatment; the extraction parameters are as follows: the fluid is supercritical CO ₂ , the flow rate is 15L/h, the extraction pressure is 22MPa, the extraction temperature is 30°C, and the separation pressure is 10MPa. Separation temperature 50°C, processing time 0.5;

(3) After degreasing treatment, degreasing dried loach and loach fish oil are obtained.

Embodiment 2, a kind of processing technology of loach, its step is as follows:

(1) The water content of the loach is reduced to less than 5% by drying or vacuum freeze-drying to make dried loach;

(2) Put the dried loach into the extraction kettle of the supercritical extraction device for degreasing treatment; the extraction parameters are as follows: the fluid is supercritical CO ₂ , the flow rate is 30L/h, the extraction pressure is 35MPa, the extraction temperature is 50°C, and the separation pressure is 16MPa. Separation temperature 60°C, treatment time 1.5h;

(3) After degreasing treatment, degreasing dried loach and loach fish oil are obtained.

Embodiment 3, a kind of processing technology of loach, its steps are as follows:

(1) Use drying or vacuum freeze-drying method to reduce the water content of loach to 4% to make dried loach;

(2) Put the dried loach into the extraction kettle of the supercritical extraction device for degreasing treatment; the extraction parameters are as follows: the fluid is supercritical CO ₂ , the flow rate is 20L/h, the extraction pressure is 25MPa, the extraction temperature is 40°C, and the separation pressure is 14MPa. The separation temperature is 55°C, and the treatment time is 1 h;

(3) After degreasing treatment, degreasing dried loach and loach fish oil are obtained.

Following is the comparison of the unprocessed dry loach through the present embodiment process treatment:

Comparison of Effects of Different Loach Degreasing Treatment Methods

project The smallest mesh/mesh that can be crushed Shelf life/month Is there any solvent residue Mold/cfu/g The dried loach processed by the process of the present invention 60 ≥12 none 2×10 ² Dried loach defatted with petroleum ether 50 12 have 2×10 ³ Unskimmed dried loach 30 3 none 3×10 ³

From the above comparison, it can be seen that the dry loach processed by the technology of the present invention has a longer shelf life because of defat, and the mesh size that can be crushed is smaller. It can be used as a high-quality raw material for producing loach powder, and high-quality loach fish oil can be processed and utilized simultaneously. , this method is significantly better than the prior art.

Embodiment 4, in the treatment process of the loach described in embodiment 1 or 2 or 3: before the degreasing treatment, the dried loach is cut into sections, and the length is cut into dry loach sections of 3-4 cm.

Claims (4)

1. a processing technology of loach, is characterized in that, its step is as follows: (1) The water content of the loach is reduced to less than 5% by drying or vacuum freeze-drying to make dried loach; (2) Put the dried loach into the extraction kettle of the supercritical extraction device for degreasing treatment; the extraction parameters are as follows: the fluid is supercritical CO ₂ , the flow rate is 15-30L/h, the extraction pressure is 22-35MPa, and the extraction temperature is 30-50 ℃, separation pressure 10MPa～16MPa, separation temperature 50℃～60℃, treatment time 0.5～1.5h; (3) After degreasing treatment, degreasing dried loach and loach fish oil are obtained. 2. The process for treating loach according to claim 1, characterized in that in step (1): drying until the water content of loach is 4%. 3. The treatment process of loach according to claim 1, characterized in that: before the degreasing treatment, the dried loach is cut into sections, and the dried loach is cut into lengths of 3 to 4 cm. 4. The treatment process for loach according to claim 1, 2 or 3, characterized in that in step (2), the extraction parameters are as follows: _CO2 flow rate is 20L/h, extraction pressure is 25MPa, extraction temperature is 40°C, separation The pressure is 14MPa, the separation temperature is 55°C, and the treatment time is 1 h.