Monday, January 24, 2011

New Variety of Cacao

(image via Wikimedia Commons)

In the New York Times, there is an interesting article about a recently re-discovered variety of Cacao, the plant from which chocolate is produced. This variety, known as Nacional, was formerly widely grown in South America prior to this century, but was mostly wiped out by disease. Today, the variety is very rare, but recently a genetically pure specimen was discovered and is now being made into chocolate.

Apparently this variety is unusual in that some of the cacao beans are white instead of their normal purple color, and yield a less bitter chocolate because they contain fewer anthocyanins, pigment molecules that have an astringent taste. Currently there is only one retailer of chocolate made from this newly discovered variety in the US, Moonstruck Chocolate.

This story makes me think about how plant breeding (and inbreeding) will affect the varieties of food plants that will be available to us in the future. Originally, Nacional cacao trees were wiped out by a disease to which all plants of that variety were susceptible. Among other reasons, one explanation for the severity of the infamous Irish potato famine was that many farmers were cultivating one variety of potato, which all had similar succeptibility to Blight, a plant disease. This famine killed nearly one million people. Some people predict that a similar fate will befall modern banana farmers, since almost all bananas grown for sale in the US are of one variety and grown from genetically identical trees.

Growing many varieties of one type of plant makes growing and harvesting the different varities more complicated and threfore more expensive, but it is a good way to maintain a diverse selection of plants and avoid your entire crop being decimated by one disease. Maybe in the future agriculture will find a balance between variety and cost efficiency. It's also possible that the days of bananas as we know them are numbered.

(Thanks to Lynn for the tip!)

Friday, January 14, 2011


From BoingBoing, a cool article about how to make yourself a DIY sous-vide waterbath for around $75. Normally, buying one of these puppies would cost a couple thousand.

Sous-vide is a method of cooking things in a water bath, sometimes called an immersion-circulator, in a plastic bag. It literally means "under-vacuum," a reference to the method of vacuum-sealing food in a plastic bag before cooking via this method. It's become quite trendy as of late, especially with the molecular gastronomy set.

In the above post, they point out one great use of the sous-vide method: cooking an egg. Previously on this blog, we've discussed protein denaturation, even specifically as it relates to eggs. That is, the way that proteins unfold when exposed to high heat or another denaturing environment. Egg proteins denature and coagulate at fairly low temperatures, much lower than the boiling point of water, for instance. By boiling or frying an egg, we transfer a lot of heat to the egg very quickly and rapidly denature and coagulate the proteins. By instead using sous-vide, you slowly bring the egg proteins to the point at which they denature and coagulate. The temperature does not exceed this point, so the egg attains a texture unlike that of eggs cooked using any other method. Of course, this takes much longer than frying an egg - cooking anything sous-vide takes longer since the difference in temperature between the food and the surrouding cooking medium is lower. I'm sure Ferran Adria would say it's worth the wait.