Advances in the analysis of aromatic compounds in hop ?nugget? from Patagonia

GONZALEZ, S.; GASTALDI B; SILVA SOFRÁS, F.; VAN BAREN CATALINA; DI LEO LIRA PAOLA; RETTA DAIANA; BANDONI, AL,

Simposio; 8th Brazilian Symposium on Essential Oils (SBOE); 2015

SBOE

In the manufacture of beer malt addition with small and varying amounts of two groupsof hops (Humulus lupulus L.) which provide the bitter taste and the flavor profile of thebeverage depending on the composition of its hundreds of volatile constituents.Overall, it is considered that there are four types of scents provided by the different hopvarieties: 1, fats and green notes for the presence of aldehydes; 2, citrus chords (neroland linalool); 3, fruity or floral notes due to the presence of certain alcohols and esters;4, herbaceous and spicy notes provided by sesquiterpenes and their oxidized formsgenerated during the beer processing (1,2). (E)-caryophyllene and α-humulene are twokey sesquiterpene compounds in most of the varieties. Its percentage ratio allowsdifferentiating between varieties. Other important sesquiterpenes compounds are offarnesene and selinene nuclei. Furthermore, the presence of myrcene is undesirablefor giving a "chemical or solvent" aroma; however, this compound is easily volatilizedduring processing of the beverage. The presence of sulfur compounds is also of utmostorganoleptic importance for its low odor thresholds that have been studied by severalauthors. New varieties of hops with new aromatic profiles are prized as a way toproduce novel types of beer. In Argentina, ?Nugget? is a variety characterized amongthe bitter ones (high humulones), for this reason the volatile components of this varietyof hop from Patagonia, Argentina, were isolated by hydrodistillation and analyzed byGC / FID / MS. 102 constituents were identified, being the main: myrcene: 62.4%, α-humulene: 11.7%, (E)-caryophyllene: 4.6%; methyl cis-4-decenoate: 1.6%, methyl 4,8-decadienoate: 1.5% and linalool: 1.0%. Hop Nugget from Patagonia presented highmyrcene content compared with hops from the same variety of other regions; however,this monoterpene disappears to a great extent during brewing. Besides, minimalamounts of 2-nonanol and methyl 3,6-dodecadienoate were detected, both regarded astypical markers of this variety. The ratio α-humulene/(E)-caryophyllene, used tocharacterize different varieties, was 2.5, similar to the values found with Nugget fromSpain (1.6) and from the United States (3).