What is E577?
Complete guide to understanding E577 (Potassium Gluconate) in your food
The Quick Answer
E577 is potassium gluconate, an organic mineral salt made from gluconic acid (derived from glucose) bonded with potassium.
It’s used in food as an acidity regulator, stabilizer, sequestrant, and—most importantly—as a potassium mineral source for dietary supplementation and nutritional enhancement.
Unlike many food additives that are purely functional, E577 provides genuine nutritional benefit by supplying bioavailable potassium, making it particularly valuable in health-conscious and low-sodium products.
📌 Quick Facts
- Category: Stabilizer, acidity regulator, sequestrant, potassium supplement
- Chemical form: Potassium salt of gluconic acid
- Also known as: Potassium salt of gluconic acid, potassium D-gluconate
- Found in: Dietary supplements, low-sodium foods, pudding powders, beverages, infant formula, food for medical purposes, weight-control products
- Safety: FDA approved, EFSA approved, WHO approved
- Acceptable Daily Intake (ADI): “Not specified” set by JECFA in 1997; “quantum satis” principle applies (use as much as needed)
- Source: Fermented glucose (fermentation of glucose to gluconic acid, then neutralized with potassium)
- Potassium content: Contains 16.69% elemental potassium by mass (or 17% depending on purity)
- Physical form: White to slightly yellow, free-flowing crystalline powder or granules, slightly bitter/saline taste
- Solubility: Freely soluble in water (approximately 900 g/L at 20°C)
- Dietary restrictions: Suitable for vegetarians and vegans (plant-derived)
- Notable advantage: Provides bioavailable potassium alongside functional benefits
What Exactly Is It?
E577 is the potassium salt of gluconic acid.
Gluconic acid is a naturally occurring organic acid created by oxidizing glucose (fermentation). When gluconic acid is chemically bonded with potassium, it creates potassium gluconate—a white crystalline compound that dissolves in water.
This compound is simultaneously a food additive (providing functional properties) and a nutritional supplement (providing potassium), making it unique among food additives for its dual benefit.
Chemical formula: C₆H₁₁KO₇ (monopotassium salt of gluconic acid)
How it’s made:
The production process is straightforward:
• Step 1 – Fermentation: Glucose undergoes bacterial fermentation (typically using Gluconobacter species) to produce gluconic acid
• Step 2 – Neutralization: The gluconic acid is neutralized with potassium carbonate (K₂CO₃) to create potassium gluconate
• Step 3 – Purification and drying: The product is purified and dried to create the final additive
Potassium content: E577 contains 16.69-17% elemental potassium by mass. This means approximately 5.99 grams of E577 contains 1 gram of potassium (100 mg of elemental potassium per 600 mg of E577).
Where You’ll Find It
E577 appears in a growing range of health-focused and specialized food products:
• Dietary supplements and nutritional supplements
• Low-sodium and low-salt food products
• Infant formula and baby food
• Food for special medical purposes
• Weight-control and meal replacement products
• Fortified beverages and drinks
• Pudding and custard powders
• Bakery products (certain formulations)
• Confectionery (sugar-free or low-calorie products)
• Meats and processed meat products
• Fish and fishery products
• Dairy products and cheese alternatives
• Fats and oils (emulsions)
• Soups and sauces
• Products for cardiovascular or electrolyte health
E577 is less common than E578 (calcium gluconate) in regular processed foods, but appears frequently in specialized products targeting specific health needs—particularly products marketed for cardiovascular health or potassium supplementation.
Why Do Food Companies Use It?
E577’s primary function is stabilization combined with potassium fortification.
Food manufacturers use potassium gluconate for multiple strategic advantages:
• Potassium fortification: Adds bioavailable potassium for genuine nutritional benefit
• Sodium replacement: Acts as a salt replacer—critical for low-sodium product formulations
• Stabilization: Prevents ingredient separation, maintains product consistency
• Buffer salt: Regulates and maintains pH stability
• Sequestrant: Binds metal ions that could cause discoloration or rancidity
• Anti-caking agent: Prevents powder products from clumping
• Electrolyte balance: Provides potassium for sports drinks and specialized beverages
• Thickening/firming: Improves texture and mouthfeel
• Chelating agent: Removes unwanted minerals that interfere with product quality
• Yeast nutrient: Provides potassium for bread leavening and fermentation
• Clean label advantage: Often labeled simply as “potassium gluconate” or “potassium,” making it attractive for “natural” marketing
• Health marketing: Enables “contains potassium” or “potassium-enriched” claims on labels
Strategic advantage: E577 allows food manufacturers to reduce sodium (addressing blood pressure and cardiovascular health concerns) while simultaneously adding potassium (also supporting cardiovascular health). This dual benefit is increasingly important in products targeting heart-health conscious consumers.
Is It Safe?
E577 is one of the safest food additives and is extensively approved.
Approval status:
• FDA approved: Listed as a nutrient supplement and sequestrant in food
• EFSA approved: Listed in Commission Regulation (EU) No 231/2012 as an authorized food additive
• JECFA approved: Listed with ADI “not specified” (set in 1997)
• WHO approved: Recognized by World Health Organization
• International approval: Approved in Australia, New Zealand, and most countries worldwide
• Uses: Categorized as “Group I” with “quantum satis” use levels (use as much as needed for functional purpose)
Safety profile:
• ADI: “Not specified” by JECFA—indicating no safety concerns at approved levels
• Toxicity: No documented toxicity at food use levels; extremely high safety margin
• No carcinogenicity: No evidence of cancer-causing potential
• No reproductive effects: Safe for use during pregnancy and breastfeeding
• Natural metabolism: Body metabolizes it as potassium and gluconic acid from natural sources
• Bioavailability: Provides bioavailable potassium; well-absorbed by the body
• Medical use: Used pharmaceutically for treating low potassium (hypokalemia)
• No documented adverse effects: No widespread adverse effects documented at food use levels
Important consideration—potassium intake:
While E577 is safe, potassium intake must be moderated in certain populations:
⚠️ Important Note on Potassium Intake:
While E577 (potassium gluconate) is safe as a food additive, excessive potassium intake from any source can be problematic for:
• Chronic kidney disease patients: Kidney function impairment reduces potassium excretion; excessive intake can cause dangerous hyperkalemia (high blood potassium)
• People on potassium-sparing diuretics: These medications increase potassium retention; E577 consumption could cause harmful potassium accumulation
• People on ACE inhibitors or ARBs: These blood pressure medications increase potassium retention
• People with diabetes: Increased risk of hyperkalemia; should monitor potassium intake
• Infants and young children: Have different potassium requirements; E577 is permitted in infant formula but in carefully controlled amounts
For these groups, while E577 is “approved as safe” for the general population, excessive consumption may not be appropriate. Always consult a healthcare provider if you have any of these conditions and are consuming potassium-fortified products regularly.
Natural vs Synthetic Version
E577 is derived from natural glucose but involves processing:
Source and production:
• Glucose starting material: Derived from corn, sugar cane, or other natural sources
• Fermentation method: Most modern production uses bacterial fermentation of glucose (natural process)
• Potassium bonding: Chemical process to create the salt
• Final product: Chemically identical regardless of production method
Perceived “naturalness”: E577 is often perceived as more “natural” than synthetic additives because it’s derived from glucose (a naturally occurring sugar) and potassium (a natural mineral). However, regulatory classification is “food additive” rather than “natural” due to the processing involved.
Vegetarian/vegan status: E577 is fully vegetarian and vegan (not derived from animal products). The potassium source is inorganic mineral potassium, and the gluconic acid is produced from glucose through fermentation.
Natural Alternatives
Want to avoid E577 or looking for potassium sources?
Some alternatives include:
• Calcium gluconate (E578) – Similar stabilizer; provides calcium instead of potassium
• Potassium citrate – Alternative potassium source; higher potassium content (13.9% vs. 16.69%)
• Potassium chloride – Simple potassium source; salty taste; highest potassium content (52.4%)
• Whole food sources of potassium: Bananas, avocados, sweet potatoes, spinach, beans, nuts, fish, yogurt
• Low-sodium salt substitutes – Often contain potassium chloride (check labels)
• Plant-based foods: Most vegetables and legumes contain natural potassium
• Simply avoid fortification – Obtain potassium from natural food sources
Comparison to Related Compounds
E577 differs from related gluconate additives:
• E574 (Gluconic acid): Base compound without mineral salt bonding
• E576 (Sodium gluconate): Similar stabilizer; provides sodium instead of potassium (not recommended for low-sodium products)
• E578 (Calcium gluconate): Similar stabilizer; provides calcium instead of potassium
• Other potassium sources: Potassium citrate, potassium chloride (different chemical forms; different properties)
The Bottom Line
E577 (potassium gluconate) is a safe and beneficial food additive that combines functional food technology with nutritional enhancement.
It’s found in dietary supplements, low-sodium products, infant formula, specialized beverages, and products marketed for cardiovascular or electrolyte health—where it serves as both a stabilizer and a potassium source.
E577 is approved by the FDA, EFSA, WHO, and virtually all regulatory bodies worldwide.
Key advantage over most additives: E577 isn’t purely functional—it provides genuine nutritional benefit by supplying bioavailable potassium. This makes it one of the rare instances where an E-number additive actually improves the nutritional value of food rather than just improving appearance, texture, or shelf life.
Potassium considerations: While E577 is safe for the general population, people with chronic kidney disease, those on certain blood pressure medications, or those with diabetes should consult their healthcare provider before regularly consuming potassium-fortified products, as excessive potassium intake can be dangerous for these groups.
For healthy individuals with normal kidney function and not taking medications that affect potassium, E577 at approved levels is considered safe. In fact, for people concerned about adequate potassium intake and needing to reduce sodium, E577-containing products offer a beneficial option.