Liquid citric acid shows up as a clear or slightly yellowish watery solution. This substance comes from citrus fruits like lemons and limes, but in the industrial world, it gets produced mainly by fermenting sugar with certain types of mold, like Aspergillus niger. The typical molecular formula looks like C6H8O7. That’s three carboxyl groups, which makes it highly acidic. Most people know citric acid from food and drink, but its uses reach far beyond fizzing up lemon soda. In liquid form, it blends into water smoothly, giving anyone in food processing or cleaning a ready-to-mix ingredient that does its job with no fuss.
Liquid citric acid offers a density around 1.26 g/cm3 at 20 °C, making it heavier than water but still manageable for those in a factory or lab. The solution has a tart, sour taste and a pH that hovers near 2, which means serious acidity—enough to break down scale, rebalance food flavors, or knock out some bacteria, though not enough for sterilizing medical gear. Its crystal structure in solid form reveals a compact lattice, but as a solution, those molecules flow loose and ready to react. This versatility keeps it in demand for food, beverage, pharmaceuticals, cleaning products, and cosmetics, always as a dependable pH adjuster, preservative, chelating agent, or descaler.
While solid citric acid usually appears as colorless crystals, white flakes, or even powder, the liquid version passes for clear or faintly yellow. It blends evenly, so it doesn’t leave residues or clumps the way powder sometimes can if dumped in one go. Some suppliers produce citric acid in pearls or granulated forms for different applications, but industries working on larger volumes usually prefer the liquid or concentrated solution, measured by the liter. Chefs and cleaning professionals often appreciate the ready-to-mix liquid because it skips the dissolving step and mixes instantaneously, especially in cold water where powder might linger at the bottom of a bucket.
Most commercial citric acid starts with corn or cane sugar, thanks to the starches and sugars they provide for fermentation. After fermentation, filtration, and purification, producers spray-dry the result into powder or keep it as liquid, depending on where it's headed next. In kitchens, a splash of liquid citric acid sharpens flavors, preserves jams, and prevents browning in fruit salads. In cleaning, that same acidity strips limescale and soap scum from kettles or coffee makers. Factories use citric acid to treat water, etch metal, or even balance the acidity in pharmaceuticals. The HS Code 29181400 tracks this acid in international trade, reflecting its status not just as a food ingredient but a chemical raw material with reach across many sectors.
Safe handling matters. Though citric acid gives lemons their tang, concentrated liquid splashed in the eyes or left on skin can sting or burn. Workers and at-home users both need to remember its low pH. This chemical won't eat through stainless steel or plastic, but corroded iron or damaged ceramics can suffer over time. Regulators don’t see citric acid as harmful in small amounts, but constant exposure or careless handling raises risk for irritation to skin, eyes, and sometimes lungs if vapor is present. Any chemical strong enough to de-scale boilers needs respect. Keeping gloves and goggles close makes sense, especially with concentrated forms or in production settings.
The main empirical formula reads as C6H8O7. For liquid solutions shipped in bulk, concentrations usually range from 20% to 50% by weight, balancing potency and safe handling. Density can shift slightly based on temperature and concentration, so suppliers test each batch and share full specs for industrial buyers. Crystal forms pack tight, while flakes and pearls offer slower dissolve rates or easier scooping. In every situation, knowing the acid’s purity, density, concentration, and storage needs makes the difference between a smooth production run and unwanted surprises. Citric acid solution comes from simple origins—sugar, fermentation, chemistry—but its role as a raw material winds through cleaning, cooking, medicine, and manufacturing.
