Isomerized Hop Extracts

Preparation:	alpha acids are separated as alkali metal salts from whole resin extract, isomerized and taken up in buffered water
Major Role:	provision of hop bitterness in whole or in part to beer
Method of Use:	used on post-fermentation basis by metered injection into beer lines

Composition
Alpha acids (HPLC)	0	-	0.8%
Beta acids	0	-	0.3%
Fats and waxes	0	-	0.3%
Aroma	absent
Bitter units (iso-alpha)	29	-	31% (w/v)
Potassium carbonate buffered water	68	-	70%

Specifications
pH (1% soln.)	9.0	-	9.5
Haze (1% soln.)	0	-	5 (EBC)
Gushing test	Nil

Advantages
-	very easy to handle, ship, store and use
-	totally consistent and standardized
-	product with highest utilization rate (65-70%)
-	provides for very easy adjustment of bitterness
-	allows production of beers with varying bitterness from a single base beer
-	almost totally inert in aroma terms (non-variety specific)

Disadvantages
-	too costly as exclusive source of bitterness
-	brewer must still consider sources of hop aroma and flavour
-	”chemically processed” product
-	reputed association with gushing - now shown to be false

Composition