Overview
ISO 3513:1995 - "Chillies - Determination of Scoville index" is an ISO method for measuring the pungency (hotness) of chillies, whole or ground, unadulterated by other spices. This second edition (1995) cancels ISO 3513:1977 and specifies a sensory-based laboratory procedure that combines solvent extraction and dilution series with a trained tasting panel to quantify the Scoville index.
Key topics and technical requirements
- Scope: Applies to chillies (commonly Capsicum frutescens) not mixed with other products; defines a standardized sensory method for Scoville index determination.
- Principle: Ethanol extraction of a test portion, filtration, preparation of aqueous dilutions and sensory testing by a panel to determine the greatest dilution at which pungency is perceived.
- Reagents & materials:
- Ethanol 95% (v/v) for extraction
- Sucrose solution 50 g/L for dilution
- Grade 3 water (ISO 3696)
- Apparatus: Volumetric flasks (50 ml, 100 ml), graduated and one-mark pipettes, filter paper, 50 ml beaker, analytical balance (±0.001 g).
- Sampling & sample prep: Sampling guidance referenced (ISO 948) and sample preparation per ISO 2825 when necessary.
- Extraction & dilution: Shake and stand extraction sequence; prepare a series of dilutions according to predefined schedules (A–F) and tables that map extract volumes to Scoville dilution factors.
- Sensory panel & tasting protocol:
- Panel of five trained assessors selected and monitored per ISO 8586-1 and ISO 3972.
- Each assessor receives six-tube sample series; sip, swallow, and report pungency perceived between 20–30 seconds after swallowing.
- Water at 35–40 °C to rinse; 5-minute intervals between samples.
- Expression of results: The Scoville index is the highest dilution factor at which at least three assessors detect pungency. (Some dilution tables require multiplying the factor by 1 000 as noted in the standard.)
Applications and users
ISO 3513:1995 is useful for:
- Spice producers and processors conducting quality control of chilli batches
- Food testing and sensory laboratories measuring pungency for labeling or product development
- Regulatory and trade bodies requiring standardized Scoville reporting
- Research institutions studying Capsicum pungency and cultivar comparisons
Keywords: ISO 3513, Scoville index, chillies, pungency, sensory analysis, ethanol extraction, Capsicum, spice quality control.
Related standards
This ISO method delivers a reproducible, internationally recognized sensory procedure for quantifying chilli heat, enabling consistent Scoville index reporting across laboratories and industry stakeholders.
