Calcium Citrate Tetrahydrate takes shape as a crystalline compound, recognized for its role in supplementing calcium in food, pharmaceuticals, and a range of industrial uses. With the chemical formula Ca3(C6H5O7)2·4H2O, this substance appears as a colorless to white solid. In daily experience, the compound arrives either as dense, free-flowing powders, shimmering flakes, or sometimes as granules and pearls, each reflecting a subtle crystalline shine. Its molecular weight reaches 570.49 g/mol. Its density typically stands close to 1.8 g/cm3, which, compared to more compact minerals, gives it a slightly airy quality. Water holds onto the structure, forming the tetrahydrate, which boosts its appropriateness as an additive that disperses easily in solutions and mixes effectively in both liquid and solid forms.
Calcium Citrate Tetrahydrate’s structure revolves around calcium ions bound to citrate anions, with four water molecules per formula unit. This coordination sets the stage for its hydrophilic nature, giving it a high solubility among common calcium salts. The physical form usually ranges from fine, chalky powders to larger, crystalline solids. The powder clings less to surfaces than other supplements; think about gently pressing a scoopful — it feels soft, almost silky, not rough or gritty. That distinct texture translates into easy handling across production lines, making it popular not just in tablet pressing but also for blending in fortification processes in dairy and plant-based drinks.
Manufacturers turn out Calcium Citrate Tetrahydrate to established standards, often aligning with specifications required by the food, pharma, and personal care industries. Purity usually exceeds 98%, with minimal levels of heavy metals or other contaminants present. The typical assay on a dry basis confirms at least 21% elemental calcium content. As consumers and patients increasingly pay attention to ingredient safety, that level of purity matters even more. The raw material source also carries weight — most comes from processed citric acid byproducts or natural limestone, with careful quality control to rule out hazardous impurities. Its HS Code classifies as 2918.15 under international standards, easing its movement through global trade channels.
A range of forms — powder, flakes, and even pearls — offers flexibility to end-users. Chefs and food technologists look for flowable granules for even dispersion, while tablet manufacturers require the fine powder for direct compression. Liquid suspensions pop up in medical and nutritional drinks, with crystal and pearl options supporting particular industrial uses, such as buffering agents or water purification. The shape reveals clues about the production process, with pearls often suggesting fluid bed granulation and flakes reflecting plate crystallization. Every format delivers the compound’s mild flavor profile and medium-intensity reactivity, which reduce taste impacts when blended into food or medication.
Any chemical deserves respect for its hazards, but Calcium Citrate Tetrahydrate ranks among the safer calcium sources. The compound avoids the lung hazards of calcium oxide, and it sidesteps the strong alkalinity found in calcium hydroxide. As an irritant, exposure may cause mild discomfort, generally limited to dust in the eyes or, rarely, to skin when handled without gloves for hours on end. Inhalation at industrial levels could lead to coughing or minor irritation, but typical use rarely sets off problems. Still, compliance with safety data sheets (SDS) remains part of responsible practice. Harmful reactions prove rare, with virtually no environmental persistence or long-term toxicity expected under normal handling conditions.
Understanding its formula, Ca3(C6H5O7)2·4H2O, gives researchers insight into binding properties, solubility, and interaction with other nutrients or excipients. The tetrahydrate form means the molecule brings four water molecules along for the ride, so any formulation or reaction must account for that built-in moisture. Material scientists look to its stability, with the tetrahydrate resisting breakdown in normal storage, enduring months in sealed containers before showing any clumping or caking. In practice, the substance often starts as citric acid, neutralized by calcium carbonate or hydroxide, yielding a product ready for broad deployment — not just nutritional applications but also water softening, buffering, and even plant nutrition.
With specific gravity close to 1.8 g/cm3 and mild hygroscopicity, the product handles storage with less fuss than many salts. Unlike calcium chloride or nitrate, it does not draw as much moisture from the air, so bags and bins avoid the rock-hard clumping that plagues some minerals. The solubility registers as moderate; water at room temperature dissolves about 0.8 g per 100 mL, sufficient for fortification but less than you’ll find in highly soluble calcium sources. These characteristics matter most when precise dosing or reliable texture matter — such as in clear beverages, puddings, or dry mixes.
Practical handling suggests keeping the dust down and using standard precautions, but the overall risk profile remains low. In years of working with nutritional supplements, the worst incidents often traced to poor ventilation or accidental spills, quickly mopped up with simple tools. Calcium Citrate Tetrahydrate does not carry risks of toxicity at normal doses and neither children nor pets suffer adverse effects if they run across it by accident, barring excessive ingestion. Still, like all chemicals, it deserves a label and secure storage away from incompatible substances such as strong acids or concentrated alkalis, which might react with the citrate component.
Future improvements revolve around more accurate moisture control, purer raw materials, and safer packaging. As regulatory agencies update standards, producers respond with tighter monitoring and new analytical methods. For users in loud, dusty factories, simple solutions like local ventilation, vacuum clean-up systems, and sealed containers reduce human and environmental exposure. Researchers continue to probe the limits of the molecule, testing for rare contaminants or trace metals using ever-finer instruments, addressing concerns before they reach the customer.
Calcium Citrate Tetrahydrate stands as a hard-working, versatile compound bridging the worlds of nutrition, chemistry, and industry. Its mix of safety, solubility, and physical adaptability drives continued demand and innovation. Reinforcing good manufacturing practices and emphasizing regular, independent testing strengthens trust all along the supply chain, from raw material extraction to end-use formulations. Those lessons, drawn from decades in manufacturing and nutrition, shape a safer product and a more transparent conversation with everyone who counts on reliable calcium sources.
