Guar gum is a thickening powder made from the seed of the guar plant. Castor oil is a pale, viscous oil pressed from castor seed. Hydrogenated castor oil (HCO) is castor oil converted into a hard wax, and tamarind kernel powder (TKP) is a starchy powder milled from tamarind seed. All four are industrial ingredients India exports in volume, and Gujarat is central to guar and castor.
Each has several uses and several grades, so the product name alone does not tell you what you are buying.
What is guar gum, and what is it used for?
Guar gum is made by splitting guar seed, removing the husk and germ, and milling the endosperm into powder. The powder swells in cold water into a thick, smooth gel. Guar gum uses include thickening and stabilising foods such as sauces, ice cream and bakery, thickening drilling fluid in oil and gas work, and sizing and printing in textiles and paper.
Production is described in where guar gum is produced in India. Grades for food and for industry differ in viscosity, particle size and cleanliness, so state the end use when you ask for a quote.
What is castor oil used for?
Castor oil is pressed from castor seed and then refined to the grade needed. It is unusual because it is mostly ricinoleic acid, which gives it high viscosity and useful chemistry. Castor oil is used in soaps, cosmetics, paints and coatings, plastics, lubricants and as a starting material for many chemicals. The range is set out in the main uses of castor oil in industry.
Castor oil is edible only in tiny, regulated amounts and is mostly an industrial product. The seed and the meal contain a toxin, so they must be handled and labelled carefully.
What is hydrogenated castor oil?
Hydrogenated castor oil is made by adding hydrogen to castor oil until it becomes a hard, brittle wax. It melts at a higher temperature than castor oil and is stable in heat. Buyers use it in greases, coatings, waxes, polishes and some personal-care products as a thickener and structuring agent. Who buys it and why is described in what hydrogenated castor oil is.
Specify melting point, acid value, iodine value and colour. A low iodine value shows the oil has been fully hydrogenated.
What is tamarind kernel powder?
Tamarind kernel powder is made by decorticating, roasting and milling the seed of the tamarind fruit. It is a starch-like thickener, and its main use is sizing yarn in textile weaving, with further uses in paper, jute and some food and industrial products. What TKP is and who uses it covers the market.
Because TKP is a natural product, viscosity, protein, moisture and colour vary by lot, so test and fix them in your contract.
How to buy any of them
Write down the end use, the grade, the key test values and the test method. Ask for a sample and a certificate of analysis from each lot. Cost differences come from the raw seed crop, the processing level and the packing, and a real quote needs a specification. The first order should be inspected and sampled before loading, as explained in why quality drops after the first container.
If you are unsure which grade you need, book a free sourcing review, and we will help you work it out and find audited manufacturers.