Make Mine a Decaf – Genetically Engineered Coffee
March 19, 2012
Coffee is one of the most widely consumed drinks in the world. Because of it’s high caffeine content, it also counts as the most widely used stimulant drug. With increasing concern about the effects of caffeine on the body, more and more people are searching for caffeine-free alternatives, including decaffeinated coffee. This is more complex than it seems, with coffee containing more than 2,000 different chemical compounds (including caffeine) which all contribute to the taste and aroma of the drink. These need to remain as unaltered as possible to make decaffeinated coffee a viable option. New research shows how biotechnology of the coffee plant may change the face of decaf forever.
The Quest for Decaf
It is reported that coffee is worth more than $15 billion a year to the national economy of a country which produces it; extremely impressive considering many, including Brazil and Vietnam, are developing countries. Two plants dominate the market. Coffea arabica is associated with a higher quality blend and has a caffeine content of 1.2%. Coffea canephora is found in instant blends and has a much higher caffeine content of up to 4%.
Despite the popularity of these coffee plant species and their product, there are a number of people who avoid decaf, mostly to avoid the negative and addictive effects of caffeine. These include, but are not limited to, insomnia, hypertension, addiction, increased predisposition to bladder cancer, anxiety, mania and psychosis. As caffeine tolerance differs between individuals, some of these may be more pronounced.
The saving grace for these individuals is the existence of caffeine-free Coffea species, which allow people to enjoy their favourite drink without the potentikally toxic effects of the stimulant. The problem with these species is that many of them have a bitter taste, making them difficult to adapt into an enjoyable cup of coffee.
Modifying the Bean
The challenge for biotechnology is to create a caffeine-free species of Coffea without bitterness or other significant taste changes. Research since the evolution of genetic engineering has attempted to splice the genes disposing a plant to low caffeine into a species with a correct combination of compounds for the cuppa. Problems arise from the fact that Coffea seemed to be particularly resistant to growth on an agar plate, making the technology extremely difficult and almost useless in many attempts.
A breakthrough came in 2001, when an enzyme from the caffeine pathway was identified in coffee’s biggest rival, the tea plant. Shinjiro Ogita, a Japanese postdoc, isolated the gene associated with this enzyme and used a gene-silencing procedure known as RNA interference to try and block production in coffee plant. The problem is that, again, coffee wasn’t compliant. After years of trial, Ogita managed to produce just 35 transgenic seedlings. These grew into plants with 70% less caffeine than the standard coffee plant, but are particularly resistant to breeding, making them difficult to cultivate into anything commercially viable.
Evidently, there are a number of people that are opposed to genetic modification, so the limited number of Ethiopian species with low caffeine counts seem to be a particularly appealing option. These also caused problems for the scientists, particularly because these breeds don’t tend to flower uniformly and can have problems with bitter taste.
Mazzafera, a Brazilian working on caffeine-free coffee breeding for decades, eventually attempted a wild stab in the dark after working for decades with the Ethiopian breeds. He took great tasting coffee plants and soaked them in mutagenic chemicals to try. The sheer number of plants that Mazzafera tackled meant that this method produced 7 varieties exceptionally low in caffeine. These strains have the problem that they are liable to cross-breeding which may increase the caffeine back to standard rates, but Mazzafera is determined to turn these into a commercially viable decaffeinated coffee.