Bitter
The bitter taste of traditionally brewed beer is the most important thing for many beer lovers. This taste comes from Humulus lupulus, otherwise known as hops. Alongside the bitter taste, hops also ensure a better head and a longer shelf life. Growing at a rate of 10 cm per day, this plant is one of the most vigorous in the world. This is quite fortunate, given the huge amount of beer produced all over the world. However, this also involves several major disadvantages. The rapid growth requires huge quantities of water. It takes up to 50 glasses of water to produce one glass of beer. Hops also need large quantities of artificial fertiliser and are bulky to transport. Large numbers of trucks are required as a result. All in all, hops are not particularly sustainable. Finally, hops are also rather sensitive plants, and this often causes variations in quality, which can adversely affect the taste of the beer.
Genetic code
The researchers solved these problems by modifying the genetic code of yeast using the new CRISPR-Cas9 technique. This technique could be regarded as a pair of DNA scissors that can be used to cut and paste new pieces of genetic information into cells. It allowed the researchers to paste the DNA of hops, one of the things which creates the bitter flavour, into the brewer's yeast. As yeast is present in beer anyway, this eliminates all the disadvantages of hops from the beer.
Just as delicious
Yeast is normally required for fermentation, the process that develops the alcohol in the beer. Yeast has now been given a few extra tasks, which could in turn influence the flavour. The researchers therefore performed a blindfolded taste test with 27 brewery employees. Surprisingly enough, the beer with no hops was considered to be even hoppier, with no extraneous flavours. Using their new brewer's yeast, the researchers hope to be able to launch a more stable and sustainable beer in the future.
Source: Nature