Overview
EN ISO 3093:2009 - "Wheat, rye and their flours, durum wheat and durum wheat semolina - Determination of the falling number according to Hagberg‑Perten" specifies the internationally accepted Falling Number (FN) method for estimating alpha‑amylase activity in cereals. The method applies to cereal grains (especially wheat and rye), their flours, durum wheat and semolina. The FN method measures the time (in seconds) for a viscometer stirrer to fall through a gelatinized starch suspension; lower FN indicates higher alpha‑amylase activity. The standard also describes converting FN to a Liquefaction Number (LN) to estimate the composition of mixtures with known FNs. Note: the method is not suitable for determining very low levels of alpha‑amylase activity.
Key topics and technical requirements
- Scope and principle: Uses starch gelatinization and enzymatic liquefaction to assess viscosity change caused by alpha‑amylase.
- Test definition: Falling Number (FN) is the total time from immersion to fall, expressed in seconds; LN is a calculated, additive value for mixture estimation.
- Sample types: Whole grains, flours and durum semolina; guidance on sample cleaning, representative sampling and storage effects.
- Sample preparation: Mill the grain to specified particle size; recommended cooling and mixing steps to ensure reproducible results.
- Apparatus: Specifies precision viscometer tubes (inner diameter 21.00 mm ± 0.02 mm; inner height 220.0 mm ± 0.3 mm), viscometer stirrer, water bath with temperature control, electronic timer and accurate dispensers/balances.
- Reagents and environment: Use water complying with ISO 3696; determine moisture content (ISO 712) as part of result interpretation.
- Corrections and precision: Includes altitude correction equations (Annex A) and interlaboratory precision data (repeatability and reproducibility).
- Intellectual property: Notes potential patent coverage for specific Falling Number apparatus (Perten Instruments) and provides contact information for licensing.
Applications and users
- Grain quality testing: Millers, cereal laboratories and grain traders use FN to assess pre‑harvest sprouting damage and enzyme activity that affect baking and processing.
- Flour and semolina quality control: Bakers and pasta manufacturers rely on FN to predict dough behavior and end‑product quality.
- Blending and formulation: Use LN conversions to design mixtures that achieve target FN levels in finished products.
- Regulatory and commercial testing: Laboratories performing standards‑based cereal analyses for certification, inspection and supply contracts.
Related standards
- ISO 712 - moisture determination (reference method)
- ISO 3696 - laboratory water quality
- ISO 13690 - recommended sampling of cereals
Keywords: EN ISO 3093:2009, Falling Number, Hagberg‑Perten, alpha‑amylase, wheat, rye, flour, durum semolina, liquefaction number, cereal analysis, grain quality testing.