Food-Grade Magnesium Sulfate: Properties, Uses, and Safety Considerations Magnesium sulfate, commonly known as Epsom salt, is a versatile inorganic compound with the chemical formula MgSO₄. When purified to meet stringent safety standards, it is classified as food-grade magnesium sulfate, suitable for use in food, pharmaceutical, and cosmetic applications. This high-purity form is free from heavy metals, toxins, and other contaminants, ensuring its safety for human consumption and industrial use. Properties and Production Food-grade magnesium sulfate appears as a white, crystalline powder or granular substance. It is highly soluble in water but insoluble in organic solvents like ethanol. The compound is hygroscopic, meaning it readily absorbs moisture from the environment, requiring proper storage in airtight containers. It is typically produced through the reaction of magnesium oxide, hydroxide, or carbonate with sulfuric acid, followed by purification processes such as recrystallization to remove impurities. The final product must comply with international food safety standards, including those set by the FDA, EFSA, and Codex Alimentarius. Applications in Food and Beverages 1. Nutritional Supplement – Magnesium sulfate is used as a dietary mineral supplement to address magnesium deficiency, which can lead to muscle cramps, fatigue, and cardiovascular issues. It is often added to fortified foods, sports drinks, and electrolyte solutions. 2. Brewing and Fermentation – In beer production, it serves as a water-adjusting agent to enhance yeast activity and improve fermentation efficiency. It also contributes to the desired mineral profile of brewing water. 3. Food Additive – Recognized as E518 in the EU, it functions as a firming agent, acidity regulator, and stabilizer in processed foods like tofu, canned vegetables, and dairy products. 4. Coagulant in Tofu Production – Magnesium sulfate helps coagulate soy milk, contributing to the texture and consistency of tofu. Safety and Regulatory Compliance Food-grade magnesium sulfate must adhere to strict purity criteria, with limits on contaminants such as arsenic, lead, and mercury. While generally recognized as safe (GRAS) in regulated quantities, excessive intake can cause gastrointestinal distress, including diarrhea and nausea. Regulatory bodies specify maximum allowable concentrations in food products to ensure consumer safety. Conclusion Food-grade magnesium sulfate is a valuable additive in the food industry, offering functional and nutritional benefits. Its applications range from dietary supplementation to food processing, provided it meets high-purity standards. Proper usage and adherence to safety guidelines are essential to harness its benefits without adverse effects.