Method for producing degreasing peanut protein powder at low-temperature

Abstract

The invention discloses a method for preparing defatted peanut protein powder under low temperature, which solves the problems that the NSI value of the prior defatted peanut protein powder is low, so that the functional characteristics of products, such as solubility, water and oil absorbility, emulsibility, etc. are low. The technical proposal comprises preparing the defatted peanut protein powder through the primary low-temperature pre-pressing, quality adjusting, leaching, low-temperature exsolution and super fine crushing to a defatted peanut after being dried with the red skin eliminated at low temperature; the whole production process is carried out under low temperature, and the obtained defatted peanut protein powder is in white or light yellow color, has less than 6.0 weight percent of water, less than 2 weight percent of fat, more than 60 percent of protein content (N*6.25, butt), and more than 60 percent of nitrogen solubility index, long storage time, good functional characteristics, such as solubility, water and oil absorbility, emulsibility, etc., good palatability and high peanut protein utility rate.

Description

technical field [0001] The invention relates to a method for preparing protein powder, in particular to a method for preparing defatted peanut protein powder at low temperature. Background technique [0002] At present, the preparation of defatted peanut protein powder mainly adopts the method of short-time high-temperature steaming (about 27-35min), pre-pressing (about 110-115°C), leaching, and high-temperature precipitation (about 105°C) followed by ultrafine pulverization. It can reduce the residual oil rate of protein powder to less than 2%, and the protein content is about 60% (N×6.25, dry basis). However, due to the high temperature in the steaming, pre-pressing and desolventizing steps, the protein is denatured due to high temperature , the content of water-soluble protein in peanut protein powder is reduced, and the nitrogen solubility index (NSI value) drops below 50%, which greatly reduces the functional properties of the product such as solubility, water and oil a...

AI Technical Summary

Problems solved by technology

[0002] At present, the preparation of defatted peanut protein powder mainly adopts the method of short-time high-temperature steaming (about 27-35min), pre-pressing (about 110-115°C), leaching, and high-temperature precipitation (about 105°C) followed by ultrafine pulverization. It can reduce the residual oil rate of protein powder to less than 2%, and the protein content is about 60% (N×6.25, dry basis). However, due to the high temperature in the steaming, pre-pressing and desolventizing steps, the protein is denatured due to high temperature , the content of water-soluble protein in peanut protein powder is reduced, and the nitrogen solubility index (NSI value) drops below 50%, which greatly reduces the functional properties of the product such as solubility, water and oil absorption, and emulsification, and loses the functional properties in food processing. application value, and due to the Maillard reaction, the color of the cake is darkened, mostly brown, which seriously affects the palatability and the utilization rate of peanut protein

[0003] With the development of technology, low-temperature pressing technology has been vigorously promoted due to its low pressing temperature and small protein denaturation. For example, at present, the stripped peanut kernels are often sent to a low-temperature screw press for two cold pressings, and then processed by ultrafine grinding technology. To obtain peanut protein powder, because the method does not go through high temperature, the problems of protein denaturation and low NSI value are solved. However, in order to meet the effective oil yield, the speed of the screw press is relatively slow, generally controlled at 10 rpm , the energy consumption is large, and the two cold pressings require the cooperation of multiple low-temperature screw presses, and the equipment investment is also high. The most important thing is that even after two cold pressings, the residual oil rate can only be reduced to 7.5% at most ( Weight) or so, can not reach the required residual oil rate of defatted peanut protein powder below 2%, can only be called semi-defatted peanut protein powder

The high oil content of semi-defatted peanut protein powder makes it difficult to store, and its functional properties are poor, and the product color is dark, so its use is limited

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