Hop products with isomerized or reduced iso α-acids intended for use in beer brewing or elsewhere in the food industry
Hop products with isomerized or reduced iso α-acids are dissolved with methanol. The bitter acids are separated through reverse phase high-pressure liquid chromatography (RP-HPLC) and isocratic elution. They are then measured at a wavelength of 270 nm.
Hops with high moisture content have a shorter storage life; in contrast, hops that are too dry disintegrate easily and lose their lupulin.
Hops and hop products intended for use in beer brewing or elsewhere in the food industry
The moisture content of whole hops, hop powder products or pellets is determined through the difference in weight before and after drying under standardized conditions.
Hops and hop products intended for use in beer brewing or elsewhere in the food industry
After extraction with toluene, the α-acids and β-acids in the hops and hop pellets are determined using spectrophotometry.
Hops and hop products intended for use in beer brewing or elsewhere in the food industry
The polyphenols are extracted from the hops using hot water. In an alkaline environment, they form a red pigment with iron (III) ions, which is measured spectrophotometrically at 600 nm.
Barley malt (pilsner malt) and smoked malt intended for use in beer brewing or elsewhere in the food industry
The phenol fraction collected through steam distillation is mixed with 4-amino- 2,3-dimethyl-1-phenyl-3-pyrazolin-5-one (4-aminophenazone) under alkaline conditions and oxidized by potassium hexacyanoferrate(III) to form a pigment (fig. 1), which after extraction with chloroform, can be measured spectrophotometrically.
This method describes how to evaluate the flavor and aroma of malt as part of a manual inspection procedure.
Malt intended for use in beer brewing or elsewhere in the food industry.
Organoleptic evaluation of a representative sample of malt