ASTM E679-19 PDF

Full title and description

ASTM E679-19 — Standard Practice for Determination of Odor and Taste Thresholds By a Forced-Choice Ascending Concentration Series Method of Limits. This practice describes a rapid sensory test design, sample presentation format, and calculation/reporting procedures used to determine detection and recognition thresholds of substances in gases, liquids or solids.

Abstract

ASTM E679-19 specifies a multiple forced-choice sample presentation in an ascending concentration (or dilution) series (method of limits) to estimate individual and panel odor and taste thresholds. The practice distinguishes detection (awareness) from recognition (identification) thresholds, prescribes panel procedures and best-estimate and geometric-mean calculations, and provides reporting guidance for threshold results. It is intended as a rapid, general-purpose threshold method rather than a physical presentation protocol, which will depend on sample state and test context.

General information

• Status: Active / current edition (E679-19).
• Publication date: August 15, 2019 (designation E679-19).
• Publisher: ASTM International (Committee E18 on Sensory Evaluation, Subcommittee E18.04).
• ICS / categories: Sensory analysis — ICS 67.240 (sensory analysis / odor & taste testing).
• Edition / version: E679-19 (2019 edition; revises earlier E679 editions).
• Number of pages: 7 pages (concise practice document).

Scope

This practice provides a rapid sensory threshold procedure applicable to determining odor and taste thresholds of any substance in any medium (air, water, beverages, solids, etc.). It prescribes the overall experimental design (forced-choice, ascending concentration series), basic sample preparation and presentation considerations (physical presentation methods are not fixed by the practice), rules for panelist responses, calculation of individual and group best‑estimate thresholds, and recommended reporting items to ensure comparability and traceability of results.

Key topics and requirements

• Multiple forced‑choice sample presentation in an ascending concentration (dilution) series (method of limits).
• Distinction between detection (awareness) and recognition (identification) thresholds and reporting of which type was measured.
• Derivation of individual best‑estimate thresholds from response patterns and calculation of panel threshold as the geometric mean of individual thresholds.
• Panelist/assessor selection and training considerations (training can strongly influence threshold values).
• Specification of dilution step factor, number of scale steps, temperature/handling, and number of test replications in reports.
• Recommended reporting items and worked examples (appendices) to support calculation transparency and comparison across studies.

Typical use and users

Commonly used by sensory scientists, olfactometry laboratories, environmental consultants, product developers, quality control teams, and researchers who need a standardized, rapid method to estimate odor or taste thresholds. Applications include environmental odor assessment, product odor/taste characterization, water quality screening, and research into human sensory sensitivity.

Related standards

ASTM E679 references and is used alongside other sensory and olfactometry standards such as ASTM E544 (referencing suprathreshold odor intensity), ASTM E1432 (calculating individual and group thresholds from forced‑choice data), ISO 13301 (guidance on odour/flavour/taste detection thresholds), and CEN/EN 13725 (dynamic dilution olfactometry for odor concentration). These documents are complementary for specific presentation techniques, instrument-based olfactometry, or suprathreshold intensity work.

Keywords

odor threshold, taste threshold, forced-choice, ascending concentration series, method of limits, olfactometry, sensory evaluation, detection threshold, recognition threshold, panelist selection, geometric mean.

FAQ

Q: What is this standard?

A: ASTM E679-19 is a concise ASTM practice describing a rapid forced‑choice ascending concentration series method to determine odor and taste detection and recognition thresholds for substances in gases, liquids or solids.

Q: What does it cover?

A: It covers experimental design (forced‑choice presentation), response rules, calculation of individual best‑estimate thresholds and the panel threshold (geometric mean), reporting recommendations, and general sample‑handling considerations; it does not fix detailed physical presentation hardware, which depends on the sample state.

Q: Who typically uses it?

A: Sensory scientists, environmental odor consultants, olfactometry labs, product developers and QA/QC teams use it when they need a standardized, reproducible method to estimate sensory thresholds for research, regulatory screening or product comparison.

Q: Is it current or superseded?

A: The current edition is E679-19, published August 15, 2019. The document history shows earlier editions (1979, 1991, 2004/2011) and E679-19 remains the active edition; a routine review/revision work item was opened in 2024 to consider minor edits or reapproval.

Q: Is it part of a series?

A: It sits within ASTM Committee E18 (Sensory Evaluation) work and is complementary to other sensory practices and test methods (for example ASTM E544 and E1432) and international standards (ISO and EN/CEN olfactometry guidance).

Q: What are the key keywords?

A: Odor threshold, taste threshold, forced‑choice, ascending concentration series, method of limits, olfactometry, sensory evaluation, detection, recognition, panelist training, geometric mean.