© 2026 Nanjing Finechem Holdings Co., Ltd,
All Right Reserved
People worked with citrates for centuries, often by trial and error before lab science spelled out exactly what these compounds could do. Sodium citrate dihydrate took on new importance in the early 1900s, when researchers in blood storage realized it could safely keep blood from clotting, a discovery that fueled the growth of blood banks during World War I. By the 20th century, industry relied on this salt for food preservation, especially in cheese and sodas, thanks to its flavor control and ability to stabilize acidity. Today’s widespread use draws on both the curiosity and practical experiments of these early pioneers.
Sodium citrate dihydrate stands out as a white, crystalline powder that dissolves cleanly in water with no fuss, bringing a mildly salty, tart taste. It’s not a flavor powerhouse but works in the background, buffering acids, tightening tastes, and keeping foods safe to eat longer. Factories churn out tons of this salt each year, bound for shelves in food plants, pharmacies, and labs. Besides food, hospitals rely on its anticoagulant powers for blood storage and transfusions. Its reach stretches into cleaning products, personal care, and even the oilfields, where it tackles scale and corrosion.
This salt’s chemical formula is C6H5Na3O7·2H2O. Each crystal holds a fixed pair of water molecules—something scientists call “dihydrate.” Sodium citrate packs a molecular weight near 294.1 grams per mole. It melts around 150°C, but heating it to dryness pushes off the water, turning it powdery and anhydrous. It dissolves well in water, less so in alcohol, and feels cool to the touch. Because it carries three sodium atoms per molecule, it works well to shift pH, letting it buffer a solution around pH 7.6. This is one of those salts that quietly holds a factory line or a mixing tank steady, making unpredictable swings in acidity much less likely.
Manufacturers sell sodium citrate dihydrate under tight quality rules. Look on the bag and you’ll see purity figures above 99 percent, and moisture measured with care. Specifications lay out limits for heavy metals, chlorides, and sulfates. Coupled with exact manufacturing data, this labeling builds trust in food, pharma, and laboratory settings. Pharmacopeias spell out the assay methods and required purity. Product labels clearly show the chemical formula, batch number, expiration date, and storage guidelines to protect against moisture and contamination. This level of traceability goes a long way toward preventing supply chain mix-ups or quality issues, which I’ve seen create real headaches in busy production environments.
Production almost always begins with citric acid, which comes from fermenting sugar sources with specialized mold. Workers neutralize this acid with a sodium source—usually sodium carbonate or sodium bicarbonate—under controlled conditions in big reaction tanks. The process turns the acid into sodium citrate, then careful evaporation and cooling pull crystals out of the solution. Rinsing, filtration, and drying follow. Scaling up from lab bench to industrial output challenged early chemical engineers, who had to solve issues like slow crystallization and filter clogging. The resulting powder flows easily and matches the product description batch after batch—a must for food safety audits and drug regulations.
On the chemistry front, sodium citrate proves itself pretty stable. It doesn’t break down unless you add strong acids or bases. Mix it with calcium, and it forms insoluble calcium citrate—a reaction that inspired its use in water softening and in cheese emulsification. Lab chemists value its tri-sodium core: by tweaking which ions are around, students can watch precipitation, chelation, or acid-base reactions. Some industrial processes modify sodium citrate by partial dehydration to produce the anhydrous form, which keeps longer without caking. Each property finds a spot in finished products, whether that’s holding minerals in check or setting up a delicate pH balance.
Don’t get tripped up by varied names in ingredient lists. Sodium citrate dihydrate goes by trisodium citrate, citric acid trisodium salt dihydrate, E331, or even 3-sodium citrate hydrate. In food industry catalogs, the E-number system signals approval for use as a food additive. Pharmacies stock it by the United States Pharmacopeia or European Pharmacopeia names, while suppliers print out CAS numbers to head off any confusion with monohydrate or anhydrous forms. All these names trace back to one core chemical with broad utility.
Handled right, sodium citrate dihydrate stays low-risk on the safety scale. Swallow small amounts and the body quickly metabolizes it. High doses can irritate, so food and pharma rates stay tightly regulated. Warehouses must keep it dry and protect it from strong acids, which can react with the salt. Workers handling industrial bagged material wear dust masks, gloves, and goggles, learning from decades of OSHA and international guidelines. Larger facilities keep detailed SOPs and emergency procedures, drawing on accident records and government standards to build safe environments. Some countries require transport labeling as a minor irritant, but not hazardous.
Most people first meet sodium citrate dihydrate in cheese slices or sodas. Melting cheese for burger toppings or nachos? This salt keeps everything smooth. Cooks and food factories rely on it to limit sourness and keep finished products tasting "just right." Sports drinks and oral rehydration sachets use it for electrolyte balance. Hospitals depend on it in blood bags and anticoagulant tubes. Cleaning brands sneak it into detergents for its ability to soften water, cut through lime deposits, or help other ingredients do their jobs. Oilfield workers turn to it for drilling operations, fighting mineral buildup deep underground. In each area, this compound underpins products people expect to work, often without anybody thinking twice about what keeps them safe or tasty.
In the lab, sodium citrate dihydrate attracts both basic scientists and engineers looking for new uses. Researchers develop energy-efficient synthesis routes and look for ways to reduce environmental impact in production. Food science teams fine-tune cheese texture or beverage clarity. Pharma R&D works out better drug delivery formulas, leveraging its pH control in buffers for new injectables. Medical researchers study its role in anticoagulation and metabolic treatments. Industrial chemists test modifications that could make it fit new roles, like sustainable antifreeze blends. As regulations and market demands shift, innovation moves beyond established recipes, turning to automation, green chemistry, and digital tracking.
Toxicologists dug deep into sodium citrate over the years, mostly with repeated studies in animals and clinical settings. At typical levels in food and medicine, it’s cleared by metabolism with no lasting issues. High doses can change the body's electrolyte balance, which spells trouble for people with kidney or heart conditions. Regulatory authorities like the US FDA and European EFSA review new data constantly, setting maximum allowed concentrations. Occupational health experts track dust exposure and possible risks for those in production, although outside of rare allergic reactions or respiratory irritation, most risks remain low. Open access to safety databases and adverse outcome reports strengthens the trust scientists and the public show in this additive.
Looking ahead, sodium citrate dihydrate finds new jobs as industry shifts toward sustainability and digital tracking. Green chemistry trends drive research on bio-based feedstocks, aiming to lessen the environmental impact of production. Digital platforms link batches to data on sourcing, production, and transport, supporting full traceability for quality control and ethical sourcing. Advanced healthcare platforms test new medical device coatings or dialysis fluids using sodium citrate’s biocompatibility. As food and pharmaceutical regulations evolve, I expect the call for purer, more precisely labeled sodium citrate to rise. Ongoing research keeps unearthing tweaks to production and new uses, showing that old compounds can always find new relevance through hard-won innovation and careful stewardship.
Most people bump into sodium citrate dihydrate without even knowing it. This salt, made from citric acid and sodium, pops up a lot in kitchen cupboards and medical settings. In the food world, it keeps soda fizzy, gives cheese sauces that smooth melt, and helps canned products keep a safe pH. When I cooked for a living, melting cheddar for nachos was a hassle until I learned about sodium citrate. Drop a bit into the pot, and the cheese suddenly blends into silky sauce — no greasy pools, no stringiness. That’s not just a chef’s trick; it keeps fake cheese on store shelves tasting the same, box after box.
Restaurants and food companies lean on sodium citrate because it keeps foods tasting fresh and looking right. Fizzy drinks lose their punch if the acidity drops, but sodium citrate helps set the stage for bubbles to stick around. Jams and jellies set properly and don’t taste sour. Canned veggies skip that sharp, tinny taste some remember from childhood. For anyone sensitive to processed foods, checking labels for sodium citrate gives a sense of what tweak keeps food stable and consistent, batch after batch. Science calls it a “buffering agent”—in the kitchen, it means fewer flavor disasters.
Sodium citrate found a solid role in hospitals as well. As an anticoagulant, it keeps donated blood from clotting during storage and transport. When patients end up needing a sodium citrate drip, it’s often because kidneys can’t clear acid properly, throwing the whole body out of balance. Anyone who’s ever dealt with kidney stones may have heard of “citrate salts” prescribed to cut down the chances of another round of pain. This is real-world chemistry working behind the scenes to make gritty emergency room scenes smoother for patients and health workers.
Dental offices add sodium citrate to rinse solutions, helping reduce acidity in the mouth. This helps protect enamel from erosion and slows tooth decay. Pharmacists sometimes reach for it in oral rehydration products or medicines designed for upset stomachs. By neutralizing oral or stomach acid, sodium citrate can settle a queasy gut much faster than some chalky tablets. Parents with sick kids at home know the relief that comes from an effective anti-nausea drink, and sodium citrate often plays a part in that recipe.
People sometimes get nervous about long names on food labels. Sodium citrate dihydrate tends to pass more scrutiny than some additives because its origins are straightforward — citric acid, often fermented from crops, mixed with sodium. Nutritionists stress moderation, though, because every extra bit of sodium in the diet can sneak up on blood pressure. For those watching salt intake, being aware of both sodium content and where it hides in ingredient lists matters. Cooking more at home, checking nutrition panels, and choosing fresh foods over processed ones helps keep sodium citrate intake in check.
More research keeps rolling in about how food preservatives, including sodium citrate, impact gut health and broader wellness. Transparent labeling along with open public conversations give everyone a stronger foundation for informed decisions. Shoppers and cooks benefit from knowing both the magic and the limits of what sodium citrate brings to the table. Poking around and asking questions — that’s how folks learn about the science shaping their meals and medicines.
Sodium citrate dihydrate shows up on a lot of ingredient lists, especially in food and drink products most people wouldn't expect. It acts as a preservative, a pH regulator, and can even keep cheese from turning into a rubbery mess when melted. This salt, made from citric acid, lands on the FDA’s list of food additives recognized as safe. That’s an official seal of approval, but before tossing another processed snack in the cart, people want to know more.
Most households have some connection to sodium citrate without even knowing it. A splash of prepared lemon juice, a few slices of American cheese on a burger, a glass of powdered drink mix on a summer afternoon—these all likely contain this additive. Part of sodium citrate’s appeal for food makers comes from its ability to prevent spoilage and maintain flavor balance, letting groceries stay on the shelf longer and taste the same each time. Having watched countless home cooking experiments turn into strange-tasting science projects because something spoiled, I see why this ingredient earns a spot in industrial kitchens.
The question should look at both the science and what experience tells us. Scientific studies back up sodium citrate’s safety in modest amounts. The FDA, along with European regulators, checked the numbers and concluded food-grade sodium citrate doesn’t pose big risks when eaten as part of a regular diet. Published studies, like those in the Journal of Food Protection, note very low toxicity and no link with cancer or reproductive health risks. For the average person, the body just breaks it down to a bit more sodium and citric acid—substances the kidneys and liver handle every day.
My personal experience matches the research. With friends and family who follow low-sodium or kidney-friendly diets, sodium citrate sometimes comes up as an alternative to plain table salt. They find it easier on the taste buds and less likely to crank up blood pressure in normal serving sizes. No complaints about stomach upsets or mysterious symptoms pop up after meals.
Even safe ingredients require a little common sense. Sodium citrate still brings sodium to the diet, about the same as other salty additives. Processed foods pile up sodium from all sorts of sources. The Centers for Disease Control and Prevention report most Americans consume much more sodium than advised, partly because of hidden sources like this one. Extra sodium can raise blood pressure, stress the heart, and push the kidneys to work overtime.
Health experts recommend checking nutrition facts for sodium content, paying extra attention to ingredient labels on foods like flavored drinks, cheeses, and processed meat. If blood pressure or kidney health is already a concern, asking a doctor before eating products with sodium citrate makes sense. For most healthy adults and kids, a varied diet with plenty of fresh foods keeps sodium citrate intake in a safe range without effort.
To keep a diet safe and balanced, cooking at home using fresh ingredients puts control back in your own hands. Swapping out processed snacks for fruits, vegetables, and home-cooked meals automatically cuts down on additives, including sodium citrate. Watching water intake also helps the body process sodium more effectively. The best step: learn to read those long ingredient lists and nutrition panels—understanding what goes into each meal brings both peace of mind and better health.
Sodium citrate dihydrate isn’t just a name printed on chemical containers in labs and hospitals. It weaves through several layers of modern life—used to adjust acidity in foods, keep blood from clotting during lab tests, and manage health issues such as kidney stones. Yet, its functions vary based on the context, and so does the right amount to use.
In healthcare, sodium citrate dihydrate comes with serious instructions. Doctors often prescribe it for urinary alkalinization or as an anticoagulant for blood transfusions. For adults managing kidney stones, a typical prescription lands in the ballpark of 1 to 3 grams taken three to four times daily, dissolved in plenty of water. Children get adjusted doses based on body weight, most often calculated as milligrams per kilogram. The margin for dosing error is slim, as too much alkalinity can bring on metabolic issues, while too little may render the treatment pointless.
Solid guidance comes straight from pharmacology texts and institutional resources. The National Institutes of Health highlights specific numbers, emphasizing that only a healthcare professional should set the plan. Deviating from recommended amounts invites trouble, from electrolyte imbalances to stomach upset. Food authorities highlight the “as needed” principle, weighing maximum levels to ensure flavors, preservatives, and pH regulators stay within safe territory.
In food processing, numbers shift depending on what’s being made. Cheesemakers add sodium citrate dihydrate by the gram, sometimes up to 5g per kilogram for melt and taste, while soft drinks and citrusy candies use much less, typically under 1g per liter. Food safety relies on these limits; excess can leave odd tastes or even cause minor digestive upset in sensitive folks.
I once thought dumping more “stuff” in a recipe gave stronger results. After a lousy batch of homemade cheese that tasted like batteries, I figured out why standards exist. Overdosing with sodium citrate doesn’t just ruin taste, it can upset your stomach and throw off the balance in all the ways you didn’t expect. This chemical asks for respect and care.
Pharmacies and factories swear by product labels, batch control, and professional training. In my own work, I’ve seen the difference when teams double-check their measurements and consult up-to-date references. Clear labeling, user education, and stricter oversight can help close gaps. Patients should ask questions about their prescriptions and report odd symptoms right away. Small efforts—clear instructions, better dosing devices, translated guides—prevent mistakes.
Staying within the recommended dosage means reading instructions, asking experts, and not taking shortcuts with “more is better.” Progress happens when doctors explain why these numbers exist and food makers check their balances. Everyone—from clinic staff to home cooks—gains confidence by sticking to the script and keeping up with current recommendations.
Sodium citrate dihydrate serves many useful purposes, but its safe use relies on respected boundaries and shared knowledge. Good health depends not on chance, but on accuracy, communication, and a willingness to learn from both science and experience.
Sodium citrate dihydrate sits on the shelf in bags or jars, usually as a white powder. In labs or kitchens, it helps buffer solutions or keep cheese sauces creamy. Mishandling often turns a valuable ingredient into a useless mess. Most people underestimate how moisture and air can change substances that seem reliable and stable.
Moisture can sneak into almost any storage area. Sodoum citrate dihydrate clumps if it draws in water. I've pulled out bags that once poured like sand, now solid as chalk. Hygroscopic chemicals suck up water if left exposed even for short periods. That moisture not only changes how the powder behaves but can kick off slow chemical changes that aren't always visible right away. This kind of slow spoilage often catches staff by surprise, especially on humid days or in unventilated closets.
A simple trick, from years of scraping failed powders out of jars: keep sodium citrate dihydrate in well-sealed containers. Glass with a good gasket outperforms plastic over the long haul. Air will carry in tiny water droplets, so thick screw-top jars or commercial moisture-barrier bags make life easier. Toss in silica gel packets for an extra line of defense.
Many places store their chemicals under harsh overhead lights, never thinking about light’s silent damage. Sunlight ruins plenty of things quietly and quickly. Warmth doesn’t always seem risky, but repeated temperature swings knock any crystal structure out of balance. Over time, a warm corner in a lab or kitchen fills with clumps that refuse to dissolve. Keeping the temperature steady, out of sunlight, keeps sodium citrate dihydrate useable longer.
My own best experiences came from using a cabinet away from heat vents and windows, in a room that stays close to 20°C (68°F) all year. That might not sound like science, but stable environments offer steady results. Cold rooms can also work when available, reducing risk of slow breakdown.
Accidents happen fast when things aren’t labeled clearly. Sodium citrate dihydrate looks like other powders but can’t fill all the same roles. Adding a clear, dated label to each jar or tub stops confusion and helps staff know how old the contents are. Planning fresh purchases instead of bulk orders makes sense for places with low use – fresher stock always works better.
Spillage or cross-contamination ruins batches and recipes. Separate scoops and gloves prevent issues before they start. If sodium citrate dihydrate ends up exposed, transferring it right away to a dry, sealed container can mean the difference between saving and losing a batch.
A few steps make storage straightforward:
All these habits come from trial and error, and more than a few ruined batches. Most users learn through frustration that chemistry and kitchen supplies have long memories for mistakes. Paying attention to storage keeps ingredients honest and results predictable. It saves money. More importantly, it keeps staff and projects moving without nasty surprises. Sodium citrate dihydrate stays as useful as the care it’s given on the shelf.
You’ll find sodium citrate dihydrate in more products than you might expect. Hospitals often use it to manage certain blood problems, and food makers mix it into everything from lemon-lime sodas to processed cheese. The stuff acts like a buffer, keeping pH levels steady, and folks with kidney stones or heartburn sometimes get it as medicine. Despite all these uses, it’s worth paying attention to how it can affect the body.
Some people notice tummy trouble after taking sodium citrate dihydrate. Nausea and mild stomach pain show up more often in those drinking the solution for a medical reason. It can taste quite salty and sour, which sometimes leads to vomiting if someone can’t keep it down. Anyone who’s had to gulp it before a medical test probably remembers the unpleasant feeling. That doesn’t mean everyone reacts this way, but folks who tend to get queasy should take it slow and use plenty of water.
Sodium doesn’t just disappear after it’s swallowed; it sticks around in the body’s fluids. People with heart failure, high blood pressure, or kidney problems might end up taking in too much sodium, which raises blood pressure or causes swelling in the ankles or hands. Sometimes patients get blood tests to check on their sodium and other minerals, especially if they already have a chronic condition. Doctors usually warn patients about these risks, as too much sodium can make these medical issues flare up fast.
Sodium citrate changes how kidneys handle acid. That’s why doctors use it for kidney stones, since it can help prevent stones from forming. For some, though, especially if kidneys aren’t working well, the body might hold on to too much sodium or too much fluid. This can lead to shortness of breath, headaches, or confusion, and in rare cases, even seizures. Allergic reactions are extremely rare, but not impossible. Swelling of lips, itching, or trouble breathing always need quick medical attention.
No one signs up for months of daily sodium citrate if they can avoid it. Over time, too much can mess with mineral levels, most often causing a drop in potassium or calcium. This happens more in older adults, or anyone who already has trouble with their heart or kidneys. Because most people only use sodium citrate briefly, big problems are unlikely, but anyone on it for weeks or months should keep an eye on blood tests and check with a doctor regularly. Manufacturers list all potential side effects in medication guides, but speaking from experience, most folks rarely check the fine print unless something already feels off.
Doctors give exact instructions on how much and how often to take sodium citrate, based on body weight, age, and health history. Ignoring those instructions often leads to side effects showing up faster. Drinking a full glass of water with each dose helps the body process the extra sodium, and tracking any odd symptoms helps catch problems early. For anyone with ongoing health issues, checking with a health professional before starting or stopping any new supplement or medication makes all the difference. Instead of treating sodium citrate like a harmless household item, see it as a tool: useful with the right guidance, but something to respect and monitor.
| Names | |
| Preferred IUPAC name | sodium 2-hydroxypropane-1,2,3-tricarboxylate dihydrate |
| Other names |
Trisodium citrate dihydrate Citrosodine Citric acid trisodium salt dihydrate Trisodium 2-hydroxypropane-1,2,3-tricarboxylate dihydrate Sodium citrate tribasic dihydrate |
| Pronunciation | /ˈsəʊdiəm ˈsɪtreɪt daɪˈhaɪdreɪt/ |
| Identifiers | |
| CAS Number | 6132-04-3 |
| Beilstein Reference | 136763 |
| ChEBI | CHEBI:86158 |
| ChEMBL | CHEMBL1201472 |
| ChemSpider | 50565 |
| DrugBank | DB09156 |
| ECHA InfoCard | 1001323 |
| EC Number | 01-2119457026-42-XXXX |
| Gmelin Reference | 129570 |
| KEGG | C00335 |
| MeSH | D020123 |
| PubChem CID | 129712227 |
| RTECS number | GE8300000 |
| UNII | 1Q73Q2JULR |
| UN number | UN3077 |
| CompTox Dashboard (EPA) | DTXSID7036396 |
| Properties | |
| Chemical formula | Na3C6H5O7·2H2O |
| Molar mass | 294.10 g/mol |
| Appearance | White crystalline powder |
| Odor | Odorless |
| Density | 1.7 g/cm³ |
| Solubility in water | Freely soluble in water |
| log P | -3.2 |
| Acidity (pKa) | 8.32 |
| Basicity (pKb) | pKb: 3.47 |
| Magnetic susceptibility (χ) | -65.0e-6 cm³/mol |
| Refractive index (nD) | 1.437 |
| Viscosity | Viscous liquid |
| Dipole moment | 2.49 D |
| Thermochemistry | |
| Std molar entropy (S⦵298) | 254.0 J·mol⁻¹·K⁻¹ |
| Std enthalpy of formation (ΔfH⦵298) | −1566.2 kJ/mol |
| Std enthalpy of combustion (ΔcH⦵298) | -234.6 kJ/mol |
| Pharmacology | |
| ATC code | A09AB02 |
| Hazards | |
| Main hazards | May cause mild eye, skin, and respiratory irritation. |
| GHS labelling | Not a hazardous substance or mixture according to the Globally Harmonized System (GHS) |
| Pictograms | GHS07 |
| Signal word | Warning |
| Hazard statements | Not a hazardous substance or mixture. |
| Precautionary statements | Keep container tightly closed. Store in a dry place. Store in a well-ventilated place. |
| NFPA 704 (fire diamond) | Health: 1, Flammability: 0, Instability: 0, Special: - |
| Lethal dose or concentration | LD50 (Oral, Rat): 5400 mg/kg |
| LD50 (median dose) | LD50 (median dose) Oral Rat: 5400 mg/kg |
| NIOSH | Not Listed |
| PEL (Permissible) | Not established |
| REL (Recommended) | 300 mg/kg |
| IDLH (Immediate danger) | No IDLH established. |
| Related compounds | |
| Related compounds |
Citric acid Trisodium citrate Monosodium citrate Disodium citrate |
