CAS Number: 7778-18-9; 10034-76-1 (hemihydrate); 10101-41-4 (dihydrate)
Other names: Plaster of Paris, Drierite, GypsumCalcium Sulphate is an inorganic compound found in nature in both a hydrated form and a dry, crystalline form. It is odourless and is most often found as a white powder. The presence of impurities will impart colours to the powder. The properties of Calcium Sulphate is very much influenced by the amount of water of crystallisation presence the molecules, and this in turns makes it useful for different applications. In the form of γ-anhydrite (the anhydrous form), it is used as a desiccant. With water, it turns into the hemihydrate a paste-like substance that dries hard. All forms are white solids that are poorly soluble in water. Calcium Sulphate causes permanent hardness in water.
1. Used in food products as additive and preservative, as anti-foaming and an anti-caking agent, Calcium Sulphate is one of the most popular food additives.
1.1 Calcium sulphate is used to coagulate soy milk to produce tofu. It is considered to be one of the richest sources of calcium and minerals. Most of the vegetarian cheese products contain gypsum which is mostly consumed by people who are intolerant to milk products.
1.2 Canned food: Gypsum is also used to preserve food items such as vegetables, fruits and jellies. A variety of other canned food items such as artificially sweetened creams, jellies and fruits also contain gypsum to preserve its self life and freshness. Fruits and vegetables tend to remain fresh due to the presence of gypsum.
1.3 Preserve frozen food stuffs: Another advantage of using gypsum includes its use to preserve frozen food. The overall content of sodium can be kept low with the addition of calcium sulfate.
1.4 Brewing process: It is also added to beer during the process of brewing. This helps to improve the shelf life of the drink and adds a certain amount of crispness to the beer.
1.5 Baked food items: Gypsum is added to baked food products such as bread and cakes. It is also included in baking powder, cereals, enriched flour and yeast as calcium supplement.
1.5 Calcium Sulphate is used by people who are intolerant to milk and milk products. It is also used in food to improve the nutritional benefit of certain edible products.
2. In the Pharmaceutical Industries
Calcium Sulphate is used as a nutritional supplement. Calcium Sulphate is widely used to manufacture calcium tablets. Deficiency in calcium causes loss of hair, weak bones and teeth, brittle nails, cramps, high cholesterol, fatigue, yellow teeth and osteoporosis.
3. As a pigment:
Calcium sulfate is a white color powder and is mixed with paints to create white paint. This type of paint is used for art painting and both exterior and interior paints.
4. Calcium Sulphate is added to cement to quicken the setting time.
5. Calcium sulfate is used as a coating agent for papers and adds thickness and durability, making the paper tougher.
6. Calcium Sulphate added to fertilizer makes the fertilizer to be acidic which is used in alkaline soil.
7. Calcium Sulphate is to remove impurities in Aluminium extraction processes.
Side effects of calcium sulphate are quite uncommon and rare, symptoms include swelling of the abdomen and gas, intense abdominal pain, irregular bowel movement, nausea and so forth.