Genotyping is the characterization of a hop variety by examination of its DNA sequences. This information is not only used in the Hopsteiner breeding program to select parents and evaluate seedlings, but molecular markers have immediate applications to quality control. For example, prior to propagation for planting a new ἀeld, the source material is tested for identity and purity by comparing its DNA ἀngerprints to an in-house database of molecular marker proἀles for refer-ence varieties. Until now, genotyping in hops, or other niche crops, lacked sufἀcient power, due to the small number of features measured in each assay and the considerable cost. Hopsteiner has solved this by applying Next Generation Sequencing (NGS) to hops, which increases the number and diversity of measured DNA features per assay -- far beyond what is required for routine genotyping.

Hopsteiner has released an exciting new hop variety bred and trialed in the Yakima Valley of

Lacing is an important visual attribute of beer. The interaction of iso-alpha acids and protein in beer is responsible for lacing. One can improve the lacing of beer by increasing the concentrations of iso-alpha acids in beer, however, this will cause an increase in beer bitterness. In our February 2014 Newsletter, we mentioned that if one isolates alpha acids from CO2 hop extract and adds it to beer, post fermentation, one can dramatically improve foam stability of beer at concentrations as low as 3 to 5 ppm. Alpha acids added to beer at these same concentrations also enhances the lacing of beer.

The Hop Storage Index (HSI) is one of the parameters to evaluate freshness of hops and hop pellets. Our newsletter of January 2012 already informed about the varying HSI within hop varieties and crop years.

Once considered a fad, then a trend, U.S. Craft beer production has become a solid component of total U.S. beer production. According to the Brewers Association, Craft beer production in 2012 topped 13 million barrels (31 US gallons or 119 Liters per barrel). Total U.S. beer production for the same period was just slightly more than 200 million barrels.

It is well known that alpha acids in hops are responsible for beers bitterness via their thermal isomerization into iso-alpha acids during the kettle boil. Alpha acids that don’t isomerize generally absorb onto the trub and yeast during fermentation, with little if any getting into the final beer.

It is well known that hop is a nitrate storing plant and therefore the concentrations are rather high, as shown in the graph below with the data from crop 2013. The various colors stand for different growing regions. Yellow (Spalt), blue (Tettnang), green (Hallertau) and red (Elbe-Saale) are the German growing areas and the US hops are presented in grey. The values vary between 4410 and 9900 mg/kg.

As in previous years we would like to demonstrate how the contribution of hop oils to beer can vary from one crop year to another. We have chosen linalool as a representative hop aroma substance as it correlates well with the sensory impression of hoppy aroma in beer.

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