Depending upon the requirement of end product various processing techniques are used. In India the commercial production of Guar gum is normally undertaken by using process of roasting, differential attrition, sieving and polishing.
The stage wise process of manufacturing food grade guar gum is as under. It is very important to select guar split in this process. The split will be screened to clean and then it will be soaked to prehydrate in a double cone mixer. Prehydrating stage is very important in the process as it derives the rate of hydration of the final product.
The soaked splits, which has reasonably high moisture content, will be passed through Flacker to take them. The flaked guar split will be ground to desired particle size followed by drying of the material. The power will be screened through rotary screens to deliver required particle size. The oversize will be either recycle to main Ultra fine or regrind in separate regrind plant, as per viscosity requirement.
This stage helps to reduce the load at the grinder. The soaked splits are difficult to grind. Direct grinding of those generates more heat in the grinder which is not desired in the process as it results in insoluble or reduced hydration of the product. Through heating, grinding & polishing process the husk is separated from the endosperm halves and the refined Guar Gum split are obtained. Through grinding process the refined Guar split are then treated and converted into powder.
During the split manufacturing process, husk & germ are obtained which are used as a cattle feed as they are rich in protein. It is widely sold in the international market as Guar Meal and has contents of Oil & Albuminoids. These contents are about 50% in germ whereas it is about 25% in husks. Quality of the food grad guar gum powder is defined from its particle size, rate of hydration and the microbial in it. E412 guar gum is an important natural food supplement with high nutritional value.