The production of strong flavor peanut oil is accomplished by improving the production process and equipment of pressed secondary oil. In the treatment of raw materials, the method of mixed processing of roasted and raw peanuts is used to improve the quality of refined oil by using the natural flavor of roasted peanut kernels. In order to keep the flavor of peanuts, physical refining is used in the refining treatment of strong flavor peanut oil to achieve the desired effect of peanut oil refining.
Cleaning: the same equipment as normal secondary oil.
Grading: separate out the immature, moldy and broken kernels from peanuts by the grading sieve. These kernels can be used to produce secondary oil and sell separately.
Drying/cooling: hot air flow drying machine can be used for drying. The moisture content of peanuts should be 5%~ 6% after drying. Then, make the temperature of peanuts lower than 40°C quickly with cold air.
Crushing/peeling: the toothed roll crusher can be used to remove the red skin of peanuts, then suck the red skin out with wind power air separator or aspirated plansifter. The red skin of peanuts can be used as the raw material of pharmaceutical and chemical industry.
Hot air roasting: put 25% ~ 30% of peanut kernels into the coal-fired hot air roasting machine and peanuts should be heated to 180°C ~ 200°C. The roasting temperature is the key factor of the aroma of peanut oil. If the temperature is too low, the flavor is light. While if the temperature is too high, the peanuts are easy to be overcooked.
Cooling and rolling: in order to prevent the peanuts from gelatinization and spontaneous combustion, they should be cooled rapidly after baking, and then rolled into broken granules by the teeth roller crusher after cooling.
Cooking: cook the peanuts with five layers vertical steam frying pan. Peanuts in the first and second layer should be full to be steamed; peanuts in 3 ~5 layers should be shallow to remove the moisture. The discharging temperature should be 108°C ~ 112°C with moisture content of 5% ~ 7%. In order to ensure the strong flavor of peanut oil, the indirect steam pressure of steam frying boiler shall be not less than 0.6mpa.
Oil pressing: model 200 peanut oil press is used in the process. Considering the particularity of strong flavor peanut oil production process, appropriate adjustments on the spindle speed of peanut oil press is made, which is improved to 10rpm from 8rpm. The cake thickness is also increased properly at about 10mm. The pressing temperature is 135°C, the pressing moisture is 1.5% ~ 2% and residual oil of press cake is 9% ~ 10%. After the crude oil has been precipitated, filter the oil by vertical leaf filter and send it to the refining workshop. After crushing, send the press cake to the extracting workshop for secondary extraction. The extracted crude oil is sold separately as conventional oil after refining.