Walnut oil peeling and cold pressing complete equipment
The pressing method is a traditional processing method in the vast walnut production areas in my country. On the basis of the traditional walnut pressing technology, Henan Taixing Grain and Oil Machinery Co., Ltd. has developed a walnut shelling, peeling and cold pressing process, which can obtain high-quality cold pressed walnut oil and pressed cakes. Can make high-protein walnut powder. The process is as follows:
Process flow: Walnut raw materials → cleaning → peeling → peeling → drying → crushing → tempering → cold pressing → virgin walnut oil
Process description: Walnuts are first transported to a vibrating cleaning sieve to remove impurities, and then metal impurities and stones are removed by a magnetic separator and a specific gravity stone remover.
After cleaning, the walnuts are peeled from the shells, and the walnut kernels and shells are separated.
Walnut kernels are peeled by adding water in a water machine, then peeled off by a separator, and finally dried by a dryer.
Using a crusher to crush the dried walnuts, the crushed walnuts are quenched and tempered and transported to the cold press for cold pressing.
This process is a cold pressing process, the residual oil is 13-20%, and the tempering temperature can also be increased. For hot pressing, the residual oil rate can be reduced to 6% while maintaining the unique aroma of walnuts.
Main equipment: vibrating cleaning screen, magnetic separator, specific gravity stone removing machine, peeling machine, peeling machine, crusher, dryer, tempering pot, etc.
Main feature: Adopting cold pressing process, tempering and pressing temperature is controlled at 60-80℃, which can better maintain protein. Cold pressed crude oil has good quality, acid value ≤1.0(KOH)mg/g, peroxide value ≤2.0mmol/kg, color R/Y<2.5/25.
Walnut oil refining equipment
Ordinary walnut oil refining mostly uses a chemical refining process. Because the soapstock produced in the alkali refining process takes many biologically active substances such as vitamin E away from the oil, so that the nutrients in the oil are reduced and the loss is considerable. Therefore, we use physical refining methods for the refining of walnut crude oil. The first stage is only degumming treatment without alkali refining to ensure that the biologically active substances are not lost and no chemical substances are added.
The deacidification and deodorization section is a distillation physical process, equipped with a patented product combined deacidification and deodorization tower developed by our company. The grease falls on the packing in the packed tower and disperses into an oil film, flows from top to bottom, and contacts with water vapor in countercurrent. , Fatty acids and various volatile substances are removed by distillation under the action of vacuum and stripping steam, so as to achieve the purpose of deodorization (deacidification). The deodorization (deacidification) process is short, which not only reduces the production cost, but also helps to inhibit the formation of trans fatty acids and preserve the retention of vitamin E.
Process flow: crude oil → degumming → decolorization → filtration → deoxygenation → heat exchange → heating → deacidification and deodorization → heat exchange → cooling → crystallization → crystal growth → filtration → refined oil
Process description: After the crude oil is preheated, hot brine is added to the oil for washing, the soap water is separated, and the degumming is completed after one or two times of the same washing. The degummed oil enters the decolorization process, adds activated clay to decolorize in the decolorization tower, and then is pumped into the leaf filter for filtration. After polishing, the filtrate enters the next process. After the leaf filter is blown dry, the waste clay is discharged through vibration. The decolorized oil is pumped into the gas separator for vacuum deoxygenation, and then the oil is pumped into the oil-oil heat exchanger and deodorized oil for heat exchange preheating, and then enters the heater when it is heated to about 250 ℃ and enters the combined deacidification and deodorization tower in high vacuum Deacidification and deodorization are carried out in the state to maximize the removal of fatty acids, odors and other volatile substances in the oil. The fatty acid mixed steam is discharged from the top of the tower into the fatty acid trapping system and sold. The oil is drawn from the bottom and pumped into the heat exchanger to exchange heat with the oil to be deodorized, and then cooled to obtain the deodorized oil. The deodorized oil is cooled and crystallized in a crystallization tank and then transferred to the crystallization stage. The oil after crystallization and crystallization is pumped into a filter to separate wax and grease to obtain refined oil.
Main equipment: centrifuge (or water washing pot), decolorization tower, leaf filter, bag filter, combined deacidification and deodorization tower, spiral plate heat exchanger, crystallization tank, dewaxing filter, etc.
Process characteristics: using physical refining technology to maximize the retention of nutrients in the oil.
The extraction and refining process of walnut oil is as follows:
Walnut → walnut kernel → 120 degree drying → pure physical walnut oil press → walnut oil → deacidification → degumming → drying and decolorization → deodorization → refined walnut oil. The best extraction and refining process: petroleum ether is used as the extraction liquid. Under 30-40 degrees, leaching for 8-10 hours, the initial temperature of alkali refining is 40 degrees, the alkali concentration is 10.45%, the total amount of alkali added can be determined according to the acid value of the crude oil (the amount of alkali added in this experiment is 0.1% of the crude oil), stir Speed 60r/min; degumming add water 2%-6%, time 5-6h, vacuum drying, vacuum degree 700-730mmHg, temperature around 110 degrees, time 50min, add activated carbon 0.5%-2%. 110 degrees decolorization 10-20min, vacuum Degree of 720mmHg, deodorization 3-5h under the condition of 190 degrees.