130 µg per capsule

Diacetyl, like butter, or butter popcorn”

Certified cider flavour standard used to train professional beer tasters to recognize and scale the intensity of diacetyl character. Butanedione is produced by yeast during fermentation. It imparts a buttery flavour to cider. High levels can be formed by malo-lactic bacteria.

Food grade | free from sensory impurities | extensively tested | safe to smell and taste.

Flavour cards

Flavour standard information

Technical specification

The best way to detect diacetyl character in cider is as follows. Without covering the glass, swirl the beer to release the aroma. Take a single short sniff. Repeat as necessary.
Amount of flavour per capsule
130 µg per capsule
40 µg / l in cider
Produced in cider from a precursor formed by yeast during fermentation. Diacetyl can also be formed by contaminant lactic acid bacteria including Lactobacillus and Pediococcus.
Diacetyl is a desirable flavour in some ciders, and an off-flavour in others. In traditional ciders it arises from secondary fermentation with malo-lactic bacteria. Such ciders have higher levels of 2,3-butanedione compared with those produced more rapidly, without a malo-lactic fermentation.
CAS registry number
The CAS registry number of 2,3-butanedione is 431-03-8.
Other names
  • diacetyl
  • biacetyl
  • 2,3-butane dione
  • butane-2,3-dione
  • 2,3-diketobutane
  • dimethyl diketone
  • dimethyl glyoxal
  • 2,3-dioxobutane
2,3-Butanedione is one of two vicinal diketones found in cider. The ratio of butanedione to pentanedione can be used as an indicator of the source of the diacetyl flavour, since bacteria produce diacetyl and no pentanedione, while yeast produces the precursors of both diacetyl and pentanedione.
Threshold distribution
Capsules per pot
Free Shipping
Product image
earn 10 points

You may also be interested in