New process for extracting stevioside by utilizing enzyme coupling membrane separation technology

Abstract

The invention discloses a new process for extracting stevioside by utilizing an enzyme coupling membrane separation technology, belonging to the technical field of food additives. The stevioside is a natural sweetener extracted from stevia rebaudian leaves, and the characteristics of high sweetness and low heat energy of the stevioside are more and more accepted by people. The existing extraction process has the defects of long extraction period, low extraction efficiency and the like, which is not favourable for the development of the stevioside industry. In the new process, the stevioside leaves serve as raw materials and are extracted at low temperature by an enzymatic method; impurities, such as colloid, pigment and the like, in the extracting solution are removed by virtue of a flocculation process; then, membrane filtration treatment is carried out by an ultrafiltration membrane with certain molecular weight cut-off; the ultrafiltrate is adsorbed, desorbed and decolorized by utilizing a resin coupling technology; and finally, the finished product is obtained by virtue of spray drying. The high-efficiency liquid chromatography proves that the total content of the nucleosidein the product obtained by the new process is above 98% which is superior to those of the international super-grade products. According to the new process, the problems of long production period, low stevioside transfer rate and the like of the conventional method can be effectively solved, and the resin service life is prolonged by more than 6 times.

Description

technical field [0001] The invention belongs to the technical field of food additives. Background technique [0002] Stevioside is a natural sweetener extracted from stevia leaves. Its high sweetness and low calorie characteristics are more and more recognized by people. It is of great development value and health respect besides cane sugar and beet sugar. Natural sweetener. [0003] In addition to stevioside (mainly including 8 kinds of glycosides), stevia leaf extract contains many impurities such as various pigments, proteins, and colloids. The current general extraction process is: stevia leaves are extracted by cold immersion, the extract is flocculated by flocculant, decolorized by activated carbon and decolorized resin, then separated and enriched by macroporous adsorption resin, and finally the finished product is obtained by spray drying. This process mainly has the following problems : [0004] (1) The conversion rate of stevioside is low, and the conversion rat...

AI Technical Summary

Problems solved by technology

[0004] (1) The conversion rate of stevioside is low, and the conversion rate in industrial production is generally about 50%, which seriously affects the economic benefits of the entire industry

[0005] (2) The extraction rate is low and the extraction period is long

[0006] (3) The extract obtained after being flocculated with a flocculant still contains a large amount of impurities and pigments, which brings a great burden to the subsequent resin treatment

[0007] (4) Activated carbon decolorization not only has poor decolorization effect, but also has strong adsorption to stevioside, which in turn causes the loss of stevioside

[0008] (5) In industrial production, it is first treated with decolorizing resin, and then enriched and desorbed by macroporous adsorption resin, which seriously affects the service life of decolorizing resin and increases the burden of post-treatment of resin