SIST EN ISO 11136:2017/A1:2020 PDF

Overview

EN ISO 11136:2017/A1:2020 is Amendment 1 to ISO 11136 (Sensory analysis - Methodology). It provides updated, normative guidance for conducting hedonic tests with consumers in a controlled area (consumer acceptability and preference testing). This European adoption (CEN) of ISO 11136:2014/Amd 1:2020 clarifies statistical procedures, sample‑size calculations and example workflows for preference, difference and non‑inferiority hedonic tests.

Key topics and technical requirements

• Test context: Hedonic (liking) and preference tests conducted in a controlled test area (laboratory or test booth setting).
• Hypothesis types: Guidance for bilateral (two‑sided) and unilateral (one‑sided) hypotheses, including difference and non‑inferiority formulations.
• Statistical procedures: Updated formulas and worked examples in Annexes F, G and H for:
  • Preference proportions (p), difference δ definitions and caution about alternate definitions of δ.
  • Sample‑size and power calculations (examples: n = 259 for p difference 0.20; unilateral case n = 211; larger examples up to n = 853).
  • Use of t‑statistics, pooled within‑product variance, and degrees of freedom for t‑tests.
  • Practical calculation notes showing Excel functions (T.INV.2T, T.INV, T.DIST) for critical t and cumulative probabilities.
• Worked examples: Step‑by‑step numerical examples for calculating t, β (type II error), and power - useful for planning and reporting.
• Reporting and interpretation: How to conclude on significant preference or non‑inferiority based on t vs. critical values and power considerations.

Practical applications

• Design and execution of consumer acceptability studies for food, beverage, personal care and other sensory products.
• Determining sample sizes and statistical power when comparing two products for preference or equivalence.
• Supporting product development decisions (reformulation, optimization) and substantiating marketing claims about consumer preference.
• Standardizing test procedures in sensory labs to produce reproducible, defensible results.

Who should use this standard

• Sensory scientists and sensory laboratories
• Product developers and R&D teams in food, beverage, cosmetics, household products
• Quality assurance specialists and statisticians supporting consumer testing
• Consultants and contract research organizations offering consumer hedonic tests

Related standards

• ISO 5495 (mentioned in the amendment) - preference test terminology and methods referenced for two‑product ranking/preference procedures.

EN ISO 11136:2017/A1:2020 is essential for practitioners who need robust, standardized methods for consumer hedonic testing with clear statistical guidance for planning, analysis and interpretation. Keywords: EN ISO 11136:2017/A1:2020, sensory analysis, hedonic tests, consumer testing, controlled area, sample size, statistical power, preference test.