The importance and origins of each flavour are:

Flavour: FLORAL-CITRONELLA    Chemical name: BETA-CITRONELLOL

“Floral-citronella, like lemon grass or insect repellent”

ORIGINS: Hop varietal characteristic. Present in hops and extracted into wort or beer. The majority of floral-citronella flavor in beer is produced by brewer’s yeast from hop-derived geraniol during fermentation.

Flavour: FLORAL-VIOLET    Chemical name: BETA-IONONE

“Floral-violet, like violets or rose water”

ORIGINS: Found in all hops and affected more by their condition and age than by hop variety. Formed as a result of degradation of carotenoid pigments in hops during growth of the plant and during post-harvest storage.

Flavour: STRAWBERRY    Chemical name: ETHYL-2-METHYLBUTYRATE

“Strawberry, like strawberry milkshake or apple juice”

ORIGINS: Hop varietal characteristic, particularly associated modern “fruity” hop varieties. Low levels of this compound are present in hops. Significant concentrations can be formed by some yeast strains during fermentation from metabolism of the degradation product of one of the hop α-acids (adhumulone).

Flavour: COCONUT    Chemical name: GAMMA-NONALACTONE

“Coconut, like coconut sun cream”

ORIGINS: It is not yet clear whether coconut flavor characteristics from hops are driven by hop variety, growing conditions, growing location, or other factors. The exact nature of the compounds responsible for coconut characteristics in beer is not yet fully understood. They most likely include -nonalactone and related compounds. Fatty acids from hops and yeast may also augment the flavor, making it more closely resemble that of fresh coconut.

Flavour: PEACH    Chemical name: GAMMA-UNDECALACTONE

“Peach, like peach or peach flavouring”

ORIGINS: It is not yet clear whether peach flavor characteristics from hops are driven by hop variety, growing conditions, growing location, or other factors. The exact nature of the compounds responsible for coconut characteristics in beer is not yet fully understood. They most likely include gamma-undecalactone and related compounds. Fatty acids from hops and yeast may also augment the flavor, making it more closely resemble that of fresh peach. Peach flavor in beer is most likely driven by the presence of fatty acid precursors in hops, which are converted into lactones by means of chemical reactions in beer or the metabolic activities of yeast.

Flavour: GREEN BANANA    Chemical name: CIS-3-HEXENYL ACETATE

“Green banana, like under-ripe banana or plantain”

Flavour: PASSION FRUIT    Chemical name: 3-MERCAPTOHEXYL ACETATE

“Passion fruit, like Sauvignon Blanc wine”

Flavour: CATTY    Chemical name: 4-MERCAPTO-4-METHYLPENTAN-2-ONE

“Catty, like tom cat urine or blackcurrant”

Flavour: LYCHEE    Chemical name: 3-METHYLTHIOHEXYL ACETATE

“Lychee, like lychee or guava”

ORIGINS: Hop varietal characteristic. Particularly associated with North American hops and “New World” hops grown in Australia and New Zealand. Examples of hop varieties with prominent lychee flavor characteristics include Galaxy and Nelson Sauvin. Imparted to beer through both kettle hopping and dry hopping.

Flavour: MELON    Chemical name: CIS-6-NONANAL

“Melon, like honeydew melon or cantaloupe melon”

ORIGINS: Hop varietal characteristic. Particularly associated with the German variety, Huell Melon. Present in hops and extracted into wort or beer. The majority of melon flavor in beer is extracted directly from hops during wort boiling, or through dry hopping during or after fermentation.