ISO 7541:2020

Overview

ISO 7541:2020 - "Spices and condiments - Spectrophotometric determination of the extractable colour in paprika" defines a standardized laboratory method to measure the extractable colour of ground paprika. The procedure measures the absorbance of an acetone extract at 460 nm using a spectrophotometer and expresses results in ASTA units. It applies to all ground paprika presentations (sweet, hot, smoked, etc.) and is based on the ASTA Method 20.1.

Key topics and technical requirements

• Scope: Quantifies extractable colour (soluble matter in acetone) of ground paprika.
• Principle: Acetone extraction of a prepared sample; spectrophotometric absorbance measurement at 460 nm.
• Sample preparation:
  • Grind so ≥99% passes an 850 µm sieve.
  • Protect sample from light.
• Reagents & apparatus:
  • Acetone (analytical grade).
  • Spectrophotometer (460 nm), 1 cm pathlength cells, analytical balance (0.1 mg), 100 ml volumetric flasks, 10 ml class A pipette.
• Procedure highlights:
  • Weigh ~0.5–0.7 g sample into 100 ml flask, fill to mark with acetone.
  • Shake and store 16 hours at room temperature, away from light; settle particles and measure absorbance using acetone as blank.
  • Recommended absorbance (A) range: 0.30–0.70. Dilute extracts with A > 0.70; increase sample mass if A