Potassium acetate (Acetate potassium)
(CH₃COOK; food additive E261(i) — acidity regulator/buffer)

Description

• Potassium salt of acetic acid with a neutral–slightly acetic taste; used as an acidulant/acidity regulator and buffer across many foods, also in low-sodium formulations as an alternative to sodium acetates.
• Supplied as high-purity granules/powder (food grade) and sometimes as solutions for continuous dosing; highly hygroscopic.

Indicative nutrition values (per 100 g; technological ingredient, not intended for direct consumption)

• Energy: ~0–10 kcal (negligible)
• Carbohydrate, protein, fat: negligible
• Total potassium: ~39–40 g/100 g (≈ 390–400 mg K per 1 g product)
• Sodium: 0 g
• Note: primarily a processing aid; potassium contribution becomes relevant only at gram-level use.

Key constituents

• Predominantly potassium acetate (conjugate base of a weak acid).
• Allowed traces of free acetic acid and moisture per spec; inorganic impurities (chlorides/sulfates/metals) within limits.
• No known intrinsic allergens; manage only cross-contact risks.

Chemical composition and structure

• Formula: CH₃COOK (monovalent salt of ethanoic acid).
• Molar mass: ~98.14 g/mol.
• Acts as a buffer in water with acetic acid (acid/base pair).
• Potassium mass fraction ≈ 40%.

Physical properties

• Appearance: white crystals/powder, odorless or faintly acetic.
• Solubility: freely soluble in water; miscible with ethanol; hygroscopic/deliquescent.
• pH (1% w/v in water): typically 7.5–9.0 (influenced by purity and dissolved CO₂).
• Melting/decomposition: ~292 °C (decomposes).
• Stability: stable at ambient when dry; absorbs moisture/CO₂ with pH drift.

Production process

• Neutralization of food-grade acetic acid with potassium hydroxide/carbonate/bicarbonate under controlled pH/temperature.
• Filtration/polishing → concentration/drying → milling/sieving to target particle size.
• Quality controls for assay, solution pH, metals, insolubles; packaged under GMP/HACCP.

Sensory and technological properties

• Acidity regulation/buffering: stabilizes pH with acetic acid, smoothing process and shelf-life variations.
• Sodium-free salt effect: useful in reduced-sodium product design.
• Antimicrobial support: acetate activity is strongest at acidic pH; can work synergistically with acetates/diacetates/lactates.
• Interactions: high doses can influence fermentations/leavening; broadly compatible with most food matrices.

Food applications

• Cooked meats/RTE: pH control and hygiene support (often blended with lactate/diacetate).
• Sauces, acid preserves, condiments: buffering for stable acidity and flavor.
• Bakery/snacks: dough/seasoning pH tuning; low-sodium option vs sodium acetates.
• Beverages/syrups: fine pH adjustment with limited flavor impact.
• Medical/clinical (out of food scope): acetate anion/electrolyte source in specific formulas.

Nutrition & health

Potassium acetate is a technological ingredient, not intended as a nutrient. It can nonetheless add dietary potassium (~40% w/w), which supports neuromuscular function and normal blood pressure within a balanced diet. Individuals with impaired renal function, on potassium-sparing diuretics, or at risk of hyperkalemia should limit intake per medical advice.
Metabolically, the acetate anion is rapidly oxidized and contributes mild alkalinizing capacity in buffer systems. The product is sodium-free, useful for low-sodium targets; any nutrition claims on finished foods must observe legal thresholds.

Portion note: Typical use 0.05–0.50% (0.5–5 g/kg) in sauces/condiments and 0.10–0.80% in meats/RTE (often in blends). In highly acidic or flavor-sensitive systems, start at 0.05–0.20% and optimize via trials.

Quality and specifications (typical topics)

• Assay (as CH₃COOK) ≥99.0% anhydrous; solution pH within spec.
• Heavy metals (Pb, As, Cd, Hg) within limits; chlorides/sulfates low; insolubles minimal.
• Loss on drying/moisture controlled; free acetic acid within limits.
• Particle size: tailored (low-dust fine powder vs low-fines granules).
• Microbiology: does not support growth; very low counts; pathogens absent/25 g.

Storage and shelf-life

• Store tightly closed, dry, and dark in moisture-barrier packaging (multi-wall bags/drums with liners).
• Avoid uptake of moisture/CO₂ (caking, pH drift).
• Typical shelf-life: 24–36 months unopened; reseal with desiccant after opening.

Safety and regulatory

• EU: additive E261(i) (acidity regulator/buffer), generally at QS (quantum satis) under GMP and category limits.
• Other jurisdictions: permitted as ingredient/additive; in the US, generally recognized as GRAS for intended uses.
• Operate under GMP/HACCP with full traceability; SDS available.

Labeling

• Names: “potassium acetate”, “E261(i)”.
• For blends with other organic salts, declare ratios; include use directions and storage statements.
• For low-sodium positioning, verify claims on the finished product.

Troubleshooting

• Over-acetic taste → excess free acid or high dose → rebalance buffer ratio (acetate/acetic), reduce dose, adjust seasoning/sugars.
• Caking → moisture ingress → stronger barrier pack, add desiccant, minimize headspace.
• Off-target pH → insufficient buffering or absorbed CO₂ → check alkalinity, prepare fresh solution, limit aeration.
• Process interference (fermentations/leavening) → high doses can inhibit microbes → reduce level or adjust buffering at critical steps.

Sustainability and supply chain

• Potential bio-based origin when acetic acid is produced by fermentation (ethanol/acetic), lowering fossil footprint.
• Plant practices: heat/condensate recovery, wastewater managed to BOD/COD targets; recyclable packaging.
• Supplier qualification, audits, and residue programs under GMP/HACCP.

INCI functions (cosmetics)

• Potassium Acetate: pH buffer, antistatic/masking agent for leave-on/rinse-off products; use per cosmetic regulations and tolerability assessments.

Film-forming agent. It produces a continuous ultra-thin film with an optimal balance of cohesion, adhesion and stickiness on the skin or hair to counteract or limit damage from external phenomena such as chemicals, UV rays and pollution.

Conclusion

Potassium acetate,  is a clean, flexible buffer for stabilizing pH and sensory profiles, with added value in low-sodium recipes. Consistent performance relies on high purity, tight moisture control, correct buffer design, and suitable packaging.

Mini-glossary

• QS (quantum satis): Use “as needed” to achieve the technological effect under good practice.
• Buffer: Conjugate acid/base system that resists pH change.
• GMP/HACCP: Good manufacturing practice / hazard analysis and critical control points — Preventive hygiene and process-control systems.
• SDS: Safety data sheet — Product safety and handling document.
• BOD/COD: Biochemical/chemical oxygen demand — Wastewater load metrics guiding treatment and discharge.
• SFA: Saturated fatty acids — High intakes can raise LDL-cholesterol; this ingredient contributes none directly.

Studies

Medical

Used in the treatment of diabetic ketoacidosis (1), also has an antibacterial function (2), in intravenous therapy in the management of hypokalaemia (3).

"Potassium acetate studies"

Molecular Formula :    C₂H₃O₂K   C₂H₃KO₂

Molecular Weight:    98.142 g/mol

CAS:    127-08-2

EC Number:   204-822-2

UNIII:    M911911U02

FEMA Number:    2920

PubChem Substance ID:24898171

MDL number:    MFCD00012458

Beilstein Registry Number:    3595449

Synonyms: 

• Acetate, Potassium
• Acetic acid potassium salt
• Diuretic salt
• Potassium ethanoate

References______________________________________________________________________

(1) Guise R, Ausherman K, Vazifedan T. Potassium-Containing Fluids for Diabetic Ketoacidosis. J Pediatr Pharmacol Ther. 2021;26(6):592-596. doi: 10.5863/1551-6776-26.6.592.

Williams V, Jayashree M, Nallasamy K, Dayal D, Rawat A. 0.9% saline versus Plasma-Lyte as initial fluid in children with diabetic ketoacidosis (SPinK trial): a double-blind randomized controlled trial. Crit Care. 2020 Jan 2;24(1):1. doi: 10.1186/s13054-019-2683-3.

Abstract. Background: Acute kidney injury (AKI) is an important complication encountered during the course of diabetic ketoacidosis (DKA). Plasma-Lyte with lower chloride concentration than saline has been shown to be associated with reduced incidence of AKI in adults with septic shock. No study has compared this in DKA. Methods: This double-blind, parallel-arm, investigator-initiated, randomized controlled trial compared 0.9% saline with Plasma-Lyte-A as initial fluid in pediatric DKA. The study was done in a tertiary care, teaching, and referral hospital in India in children (> 1 month-12 years) with DKA as defined by ISPAD. Children with cerebral edema or known chronic kidney/liver disease or who had received pre-referral fluids and/or insulin were excluded. Sixty-six children were randomized to receive either Plasma-Lyte (n = 34) or 0.9% saline (n = 32). Main outcomes: Primary outcome was incidence of new or progressive AKI, defined as a composite outcome of change in creatinine (defined by KDIGO), estimated creatinine clearance (defined by p-RIFLE), and NGAL levels. The secondary outcomes were resolution of AKI, time to resolution of DKA (pH > 7.3, bicarbonate> 15 mEq/L & normal sensorium), change in chloride, pH and bicarbonate levels, proportion of in-hospital all-cause mortality, need for renal replacement therapy (RRT), and length of ICU and hospital stay. Results: Baseline characteristics were similar in both groups. The incidence of new or progressive AKI was similar in both [Plasma-Lyte 13 (38.2%) versus 0.9% saline 15 (46.9%); adjusted OR 1.22; 95% CI 0.43-3.43, p = 0.70]. The median (IQR) time to resolution of DKA in Plasma-Lyte-A and 0.9% saline were 14.5 (12 to 20) and 16 (8 to 20) h respectively. Time to resolution of AKI was similar in both [Plasma-Lyte 22.1 versus 0.9% saline 18.8 h (adjusted HR 1.72; 95% CI 0.83-3.57; p = 0.14)]. Length of hospital stay was also similar in both [Plasma-Lyte 9 (8 to 12) versus 0.9% saline 10 (8.25 to 11) days; p = 0.39]. Conclusions: The incidence of new or progressive AKI and resolution of AKI were similar in both groups. Plasma-Lyte-A was similar to 0.9% Saline in time to resolution of DKA, need for RRT, mortality, and lengths of PICU and hospital stay. Trial registration: Clinical trial registry of India, CTRI/2018/05/014042 (ctri.nic.in) (Retrospectively registered).

(2) Liato V, Labrie S, Aïder M. Electro-activation of potassium acetate, potassium citrate and calcium lactate: impact on solution acidity, Redox potential, vibrational properties of Raman spectra and antibacterial activity on E. coli O157:H7 at ambient temperature. Springerplus. 2016 Oct 10;5(1):1760. doi: 10.1186/s40064-016-3453-1. 

Abstract. Aims: To study the electro-activation of potassium acetate, potassium citrate and calcium lactate aqueous solutions and to evaluate their antimicrobial effect against E. coli O157:H7 at ambient temperature. Methods and results: Potassium acetate, potassium citrate and calcium lactate aqueous solutions were electrically excited in the anodic compartment of a four sectional electro-activation reactor. Different properties of the electro-activated solutions were measured such as: solutions acidity (pH and titratable), Redox potential and vibrational properties by Raman spectroscopy. Moreover, the antimicrobial activity of these solutions was evaluated against E. coli O157:H7. The results showed a pH decrease from 7.07 ± 0.08, 7.53 ± 0.12 and 6.18 ± 0.1 down to 2.82 ± 0.1, 2.13 ± 0.09 and 2.26 ± 0.15, after 180 min of electro-activation of potassium acetate, potassium citrate and calcium lactate solution, respectively. These solutions were characterized by high oxidative ORP of +1076 ± 12, +958 ± 11 and +820 ± 14 mV, respectively. Raman scattering analysis of anolytes showed stretching vibrations of the hydrogen bonds with the major changes within the region of 3410-3430 cm-1. These solutions were used against E. coli O157:H7 and the results from antimicrobial assays showed high antibacterial effect with a population reduction of ≥6 log CFU/ml within 5 min of treatment. Conclusions: This study demonstrated the effectiveness of the electro-activation to confer to aqueous solutions of organic salts of highly reactive properties that differ them from their conjugated commercial acids. The electro-activated solutions demonstrated significant antimicrobial activity against E. coli O157:H7. Significance and impact of study: This study opens new possibilities to use electro-activated solutions of salts of weak organic acids as food preservatives to develop safe, nutritive and low heat processed foods.

(3) Glover P. Hypokalaemia. Crit Care Resusc. 1999 Sep;1(3):239-51. 

Abstract. Objective: To review the metabolism and function of potassium and causes and management of hypokalaemia. Data sources: A review of studies reported from 1966 to 1998 and identified through a MEDLINE search of the English-language literature of hypokalaemia. Summary of review: Potassium is predominantly an intracellular ion that contributes to approximately 50% of the intracellular fluid osmolality and is largely responsible for the resting membrane potential. The latter accounts for its influence on the excitability of muscle and nervous tissue. Hypokalaemia is defined as a serum potassium of less than 3.5 mmol/L or plasma potassium less than 3.0 mmol/L and may be asymptomatic. Clinical features associated with hypokalaemia include abnormalities of cardiovascular, neurological and metabolic function and may be treated with oral potassium salts, although tachycardia and muscle weakness are the two life threatening disorders which may require rapid intravenous correction. The potassium salts of chloride, phosphate and acetate are often used, although the choice is often guided by the presence of an associated hypochloraemic alkalosis, non-anion gap acidosis or hypophosphataemia, indicating treatment with potassium chloride, potassium acetate, or potassium phosphate, respectively. The infusion rates of intravenous therapy depends upon the salt used. Potassium chloride is usually infused at a rate up to 40 mmol/h, whereas potassium acetate and potassium monohydrogen or dihydrogen phosphate are usually infused up to 5 mmol/h and 2 mmol/h respectively.