Method of fresh squeezing / supercritical extraction phospholipid technology

Abstract

Soybeans are stored and adjusted in an after-ripening fresh-keeping bin, then the soybeans are subjected to low-temperature tempering, crushing and peeling, flaking, tempering, low-temperature instant puffing and squeezing to obtain crude soybean oil and high-valued protein, the crude soybean oil is subjected to hydration degumming to obtain soybean oil and by-product oil foots, and the oil foots are subjected to vacuum dehydration to obtain soybean concentrated phospholipid. And obtaining soybean phospholipid powder particles through a supercritical extraction technology. A novel grease preparation method for synchronously recovering high-quality protein and other active components is formed by coupling a cold pressing technology and a supercritical extraction technology, and a key technology for synchronously separating biological dissociated grease and protein products is realized.

Description

Technical Field

[0001] The invention relates to a method for fresh-squeezing / supercritical extraction of phospholipids. Background Art

[0002] Newly harvested soybeans are only mature in form, but not truly mature. They have a low germination rate, are not storable, and have poor processing and edible quality. Soybeans need to be stored in a suitable environment to effectively ensure their quality. In addition, after the soybeans are ripened, their oil yield can be effectively improved. Edible oils and fats are one of the essential nutrients for the human body. They not only provide energy for the human body, but also effectively improve the flavor of food, provide essential fatty acids and fat-soluble vitamins, etc. Soybean oil extraction is generally divided into pressing and leaching, and the pressing method is further divided into hot pressing and cold pressing according to its processing process. With the continuous improvement of people's living standards, researchers have gradually turned their attention to how to retain more nutrients in edible oils, and moderate processing has also come into people's eyes.

[0003] Cold pressing is a physical pressing of oil at a relatively low temperature. Compared with the leaching process, the pressing process is simple and can retain the nutrients in soybean oil to a greater extent. The disadvantage is that it is greatly restricted by the raw materials and the oil yield is low. In order to give full play to the advantages of raw material storage regulation and cold pressing technology, this study started with the quality of raw soybeans and controlled from the front end of the process. The soybean preservation and post-ripening storage process was transformed and explored to obtain freshly pressed soybean oil.

[0004] Supercritical CO2 extraction technology has the advantages of no chemical solvent consumption and residue, no pollution to the environment, high extraction efficiency, easy recovery, simple process, low operating temperature, which can effectively protect heat-sensitive active substances, and high quality and purity of the obtained products. Soybean oil foot is an important by-product of soybean oil refining. Soybean crude oil is degummed to obtain oil foot, and the oil foot is vacuum dehydrated to obtain soybean concentrated lecithin. Soybean concentrated lecithin is a kind of light brown or light yellow translucent viscous substance with certain functional characteristics, a slight bean smell, and easy oxidation denaturation. Soybean powder lecithin is further purified from concentrated soybean lecithin. At present, the solvent extraction method is commonly used in industrial production to prepare soybean powder lecithin. The concentrated soybean lecithin is deoiled and impurities are removed, and then dried to prepare powder lecithin. The solvent extraction method uses too much solvent and has excessive loss. It is toxic and will pollute the environment. It contains a certain amount of impurities. At the same time, the solvent residue limits the application of soybean powder lecithin in high-end food and dairy industries. The supercritical CO2 extraction method chooses not to add entrainer. Carbon dioxide can give full play to the advantages of strong solubility and diffusion ability, fully contact with the raw material particles, and effectively take away the oil substances contained in the particles, solving the problems of high impurity content, dark color and weak functionality of current soybean lecithin products, and realizing the preparation of organic soybean powder lecithin without solvent throughout the process. Summary of the invention

[0005] The soybeans are stored and conditioned in a post-ripening fresh-keeping warehouse, and then cleaned and de-impurified for low-temperature conditioning, crushed and peeled. The crushed beans enter the cold press for low-temperature pressing to extract oil, and fresh oil and oil cake are obtained respectively. After degumming, degummed oil and oil foot are obtained, and concentrated lecithin is obtained after dehydration and impurity removal. Organic soybean powder lecithin is obtained through supercritical extraction technology.

[0006] Specific implementation method: Step 1: Soybeans are stored and conditioned in a post-ripening fresh-keeping warehouse, and then after cleaning and removing impurities, they are tempered at low temperature, crushed, peeled, rolled, and tempered. Step 2: Use an extruder to expand the raw soybean embryos after rolling to make mature embryos, so that the oil is converted into porous expanded embryo sheets. Step 3: For the screw oil press, the material after rolling is fed into the feed port of the oil press, and the temperature is indirectly fine-tuned by adjusting the oil outlet gap and cake thickness of the screw oil press. The temperature can also be adjusted by adding cold oil spray, hollow pressing shaft and pressing cage water circulation, etc., so that the pressing temperature is maintained below the denaturation temperature of soybean protein, and soybean crude oil and soybean cake are obtained by pressing. Step 4: Add 0.1-0.15% hot water or diluted alkali, salt, phosphoric acid and other electrolyte aqueous solutions of soybean crude oil to the oil filtered at 85°C under stirring, so that the colloid-soluble impurities therein absorb water and condense, and then settle and separate. Heat the oil to 80-85℃, slightly lower than the water temperature (water is slightly boiling), add 5-10% of the centrifugal oil weight of deionized soft water, add 0.04-0.06% of the amount of phosphoric acid in the crude oil, and adjust the amount of alkali solution according to the quality of the crude oil. Wash with water for 3 minutes to remove residual soap and phospholipids. Use a continuous centrifuge to separate. Vacuum dehydration, heat to 110℃, and observe the transparency of the oil, bubbles, etc. during the dehydration process. Determine the number of water washings based on the residual soap in the degummed oil, generally 1-3 times. The water content of the degummed oil after drying is ≤0.10%. Step 5: Crude phospholipids are obtained by vacuum dehydration of the oil foot, a by-product of soybean hydration degumming. Step 6: Add crude soybean lecithin into the barrel and put it into the extraction tank, install the pressure ring and sealing ring, tighten the upper plug, set the extraction temperature on the temperature controller on the operation panel, heat it, set the CO2 flow rate to 28L / h, adjust the pressure control valve, set the extraction pressure, start cyclic extraction, and maintain constant pressure and temperature. After cyclic extraction for a period of time, take out the barrel from the extraction tank to obtain a powdered lecithin product.

[0007] Specific implementation method 2: The difference between this implementation method and specific implementation method 1 is that the pressing temperature is 30-60° C., and the method carried out under this condition is the same as that of specific implementation method 1.

[0008] Specific implementation method three: The difference between this implementation method and specific implementation method one is that the moisture content of soybeans is adjusted to 8%-14%. The method carried out under this condition is the same as that of specific implementation method one.

[0009] Specific implementation method 4: The difference between this implementation method and specific implementation method 1 is that the screw speed is 50-90100r / min, and the method carried out under this condition is the same as that of specific implementation method 1.

[0010] Specific embodiment 5: The difference between this embodiment and specific embodiment 1 is that the extraction pressure is 20-50 MPa, and the method carried out under this condition is the same as that of specific embodiment 1.

[0011] Specific embodiment 6: The difference between this embodiment and specific embodiment 1 is that the extraction temperature is 30-60°C, and the method carried out under this condition is the same as that of specific embodiment 1.

[0012] Specific embodiment 7: The difference between this embodiment and specific embodiment 1 is that the extraction time is 90-150 minutes, and the method carried out under this condition is the same as that of specific embodiment 1.

Claims

1. A method for fresh-squeezing / supercritical extraction of phospholipids is achieved by the following steps. Step 1: The soybeans are stored and conditioned in a post-ripening fresh-keeping warehouse, and then after cleaning and removing impurities, they are tempered at low temperature, crushed and peeled, and the crushed beans enter the cold press for low-temperature pressing to extract oil, respectively, to obtain freshly squeezed oil and oil cake. Step 2: The raw soybean embryos after rolling are puffed into mature embryos with an extruder, so that the oil is converted into porous puffed embryo sheets. Step 3: For the screw oil press, the material after rolling is fed into the feed port of the oil press, and the temperature is indirectly fine-tuned by adjusting the oil outlet gap and cake thickness of the screw oil press. The temperature can also be adjusted by adding cold oil spray, hollow pressing shaft and pressing cage water circulation, etc., so that the pressing temperature is maintained below the denaturation temperature of soybean protein, and soybean crude oil and soybean cake are obtained by pressing. Step 4: 0.1-0.15% of the soybean crude oil is added to the oil filtered by precipitation at 85°C with hot water or diluted alkali, salt, phosphoric acid and other electrolyte aqueous solutions, so that the colloid-soluble impurities therein absorb water and condense, and then settle and separate. Heat the oil to 80-85℃, slightly lower than the water temperature (water is slightly boiling), add 5-10% of the centrifugal oil weight of deionized soft water, add 0.04-0.06% of the amount of phosphoric acid in the crude oil, and adjust the amount of alkali solution according to the quality of the crude oil. Wash with water for 3 minutes to remove residual soap and phospholipids. Use a continuous centrifuge to separate. Vacuum dehydration, heat to 110℃, and observe the transparency of the oil, bubbles, etc. during the dehydration process. Determine the number of water washings based on the residual soap in the degummed oil, generally 1-3 times. The water content of the degummed oil after drying is ≤0.10%. Step 5: Crude phospholipids are obtained by vacuum dehydration of the oil foot, a by-product of soybean hydration degumming. Step 6: Add crude soybean lecithin into the barrel and put it into the extraction tank, install the pressure ring and sealing ring, tighten the upper plug, set the extraction temperature on the temperature controller on the operation panel, heat it, set the CO2 flow rate to 28L / h, adjust the pressure control valve, set the extraction pressure, start cyclic extraction, and maintain constant pressure and temperature. After cyclic extraction for a period of time, take out the barrel from the extraction tank to obtain a powdered lecithin product.

2. The difference between this embodiment and the first embodiment is that the pressing temperature is 30-60°C, and the method carried out under this condition is the same as that of the first embodiment.

3. The difference between this embodiment and the first embodiment is that the moisture content of the soybeans is adjusted to 8%-14%. The method carried out under this condition is the same as that of the first embodiment.

4. The difference between this embodiment and the first embodiment is that the screw speed is 50-90100 r / min. The method carried out under this condition is the same as that of the first embodiment.

5. The difference between this embodiment and the first embodiment is that the extraction pressure is 20-50 MPa. The method carried out under this condition is the same as that of the first embodiment.

6. The difference between this embodiment and the first embodiment is that the extraction temperature is 30-60°C. The method carried out under this condition is the same as that of the first embodiment.

7. The difference between this embodiment and the first embodiment is that the extraction time is 90-150 min. The method carried out under this condition is the same as that of the first embodiment.