ISO 20370:2009

Overview

ISO 20370:2009 defines a standardized enzymatic method for the determination of acetate content in materials used to produce wrappings for cigarette filters, cigarettes and other tobacco products. The method measures anhydrous acetic acid (expressed as a mass fraction, % by mass) using an enzyme-coupled reaction sequence and spectrophotometric detection of NADH at 340 nm. The standard is intended for quality control and laboratory testing of cigarette paper and related wrapping materials.

Key topics and requirements

• Scope: Measurement of acetate content in wrapping materials for cigarette filters, cigarettes and other tobacco products.
• Analytical principle: Conversion of acetate to acetyl‑CoA (via acetyl coenzyme A synthase), subsequent reactions produce NADH; NADH increase is measured at 340 nm to quantify acetate.
• Reagents & kits: Use of commercially available enzymatic test kits (or equivalent individual reagents). Key reagents include ATP, CoA, NAD, L‑malic acid, citrate synthase, L‑malate dehydrogenase and ACS.
• Sample preparation: Extract about 1.0 g of conditioned wrapping material in 100 ml water (ultrasonic bath or stirring for 30 min), then filter.
• Measurement: Use a double‑beam spectrophotometer; total cuvet volume typically 3.23 ml. Calibrate with sodium acetate standards (e.g., 50, 100, 300 mg/l).
• Calculations: The method provides equations to convert absorbance difference (ΔA) to acetate concentration. For standard volumes, an intermediate equation: ρ (g/l) = 2.566 × ΔA (for anhydrous acetic acid, M = 60.05 g/mol).
• Precision: Results from an interlaboratory study (nine labs) showed acetate levels tested between ~0.4% and 1.1% with reported repeatability and reproducibility estimates.
• Safety & conditioning: Warning about hazardous materials and requirement to condition samples per ISO 187; references also include ISO 287 and ISO 3696 for moisture and water quality.

Applications and users

• Tobacco product manufacturers and cigarette paper suppliers for product formulation control (burn rate, puff number).
• Independent test laboratories and regulatory enforcement bodies performing compliance testing.
• R&D and quality assurance teams assessing additive levels (sodium/potassium acetate) in wrapping materials.
• Manufacturers of filter wrappings and material suppliers seeking documented analytical methods for specifications.

Related standards

• ISO 187 - Conditioning and testing atmosphere for paper and board
• ISO 287 - Moisture determination (oven‑drying)
• ISO 3696 - Water for analytical laboratory use
• CORESTA Recommended Method No. 33 - Determination of acetate in cigarette paper

ISO 20370:2009 is a practical, validated method for consistent acetate measurement in tobacco wrapping materials, supporting quality control, formulation management and regulatory compliance.