Product Description
Sensory training kit used to train professional beer tasters to recognize and scale the intensity of six different flavour notes associated with yeast and bacteria.
Use this set of certified beer flavour standards to deliver up to 90 minutes of taster training for ten people, or as a personal flavour training kit, allowing you to train yourself to recognize each of the six flavour notes over a longer period of time.
The AROXA™ Yeast – Yeast and Bacteria – Yeast kit 1 comes complete with informative flavour cards for each standard.
AROXA™ certified beer flavour standards are: food grade | free from sensory impurities | extensively tested | safe to smell and taste. Unsure whether this kit is right for you? Don’t forget about our 100% satisfaction guarantee.
This kit contains seven flavours as detailed below.
ACETALDEHYDE
ACETALDEHYDE
HONEY
ETHYL PHENYLACETATE
COOKED VEGETABLE
METHYL THIOACETATE
SULPHITIC
SULPHUR DIOXIDE
The importance and origins of each flavour are:
Flavour: ACETALDEHYDE Chemical name: ACETALDEHYDE
“Acetaldehyde, like green apple, emulsion paint or white wine”
IMPORTANCE: Acetaldehyde is present in all beers. It is a characteristic flavour of some beer styles, eg Bière de Garde. Acetaldehyde is an off-flavour at high concentrations in beer.
ORIGINS: Acetaldehyde is produced by yeast during fermentation as the penultimate step in production of ethanol from wort sugars. Its presence is indicative of fermentation problems and poor control of dissolved oxygen in packaging.
Flavour: DIACETYL Chemical name: 2,3-BUTANEDIONE
“Diacetyl, like butter, butter popcorn, or warm milk”
IMPORTANCE: Diacetyl is a desirable flavour in some ales, stouts and lagers, eg Pilsner. It is considered an off-flavour in other lager beers. Considerable efforts are made by breweries to tightly control the concentration of 2,3-butanedione in beer.
ORIGINS: Diacetyl is produced in beer from a precursor (alpha-acetolactate) formed by brewer’s yeast during fermentation. It can also be formed by contaminant lactic acid bacteria such as Lactobacillus and Pediococcus spp.
Flavour: HONEY Chemical name: ETHYL PHENYLACETATE
“Honey, like sweet mead or sherry”
IMPORTANCE: Ethyl phenylacetate off-flavour formed during ageing in pack from precursors which are formed during fermentation. It is a positive flavour note in Honey beers.
ORIGINS: Ethyl phenylacetate is formed during ageing of beer. It tends to develop after the appearance of papery, tobacco and leathery notes, and after the loss of banana and bitter notes.
Flavour: MERCAPTAN Chemical name: METHANETHIOL
“Mercaptan, like drains or soft white cheese”
IMPORTANCE: Methanethiol is a component of the sulphury flavour character of beer. It is found in all beer styles to a degree. Methanethiol and other thiols are off-flavours when present in excess.
ORIGINS: Methanethiol arises through yeast autolysis at the end of fermentation or during maturation. It can also be contributed to beer by dry hopping and by growth of bacteria in beer.
Flavour: BOILED CABBAGE Chemical name: METHYL THIOACETATE
“Boiled cabbage, like boiled cauliflower, broccoli or cabbage”
IMPORTANCE: Methyl thioacetate is a positive sulphury flavour note in some lagers. It can be perceived as an off-flavour in other lagers and in all ales and stouts.
ORIGINS: Methyl thioacetate is produced by lager yeast (but not by ale yeast) during fermentation. The amount produced depends on wort composition, yeast strain and fermentation conditions.
Flavour: CAPRYLIC Chemical name: OCTANOIC ACID
“Caprylic, like goat hair or candle wax”
ORIGINS: Octanoic acid is produced by yeast during maturation of beer. It is released into beer from autolysing yeast cells.
Flavour: SULPHITIC Chemical name: SULPHUR DIOXIDE
“Sulphitic, like burning sulphur or young white wine”
IMPORTANCE: Sulphites keep beer fresh during storage. They affect the flavour intensity of many beer aldehydes. When added as an antioxidant, they impart a distinctive sulphury character to fresh beer.
ORIGINS: Sulphur dioxide is produced by lager (but not by ale or wheat beer) yeast during fermentation. It may be added to beer as an antioxidant in some markets.
