Categories: ACS Spring 2014 |  Comments
If you follow us on Twitter you’ll know that I spent 16-20 March in Dallas, Texas for the ACS spring conference, hearing about peptides that attack TB, dissolvable electronics and new drug testing methods.
— Chocolate absorbing volatiles from wine
I was also happy to find that – perhaps fitting for a state known for generous helpings – there was plenty of food and booze research on the scientific agenda.
First up, chocolate. We all love it, and apparently so do the bacteria that live in our guts. Dark chocolate has been linked to various heart and metabolic heath benefits in past studies. Now, a group led by John Finley at Louisiana State University, US, may have come closer to figuring out the reasons behind some these effects. Dark chocolate with a high cocoa content contains polyphenol antioxidants (such as catechins which are also found in tea), but these are poorly digested and absorbed in the gut, so this is unlikely to be the full story. Instead, say the researchers, bacteria living in the gut may play a part, munching on the undigestible parts of chocolate and fermenting polyphenols to produce smaller compounds that are more readily absorbed. The group put different cocoa powders through a model digestive tract, then fed the leftovers to human gut bacteria, and showed that some of the simpler phenolic acids produced had anti-inflammatory effects. They suggest small amounts of dark chocolate could be combined with prebiotic supplements to help healthy internal gut microbes thrive.
Another piece of chocolate-related research I happened to stumble across was a group at Salt Lake Community College’s efforts to make wine flavoured chocolate. Sydney Richards, one of the students involved, told me the inspiration was a lack of tasty wine-chocolate combinations already out there. Most wine chocolates tend to be flavoured with a liquid filling like a liqueur or crunchy crystalline pieces, and neither taste great. But the group have come up with a simpler to get the chocolate to pick up the wine flavour, without the two even having to touch. Chocolate naturally absorbs nearby volatile compounds (Richards told me her supervisor found this out to her cost after storing some chocolate in the same drawer as a bar of soap!). The group have already used this effect to capture mint, coffee and fruit flavours in chocolate, so decided to try a similar approach with wine. The set up is simple – the chocolate is put on a rack above a bowl of wine and left for about two weeks, which allows it to absorb flavour volatiles like 3-methylbutan-1-ol and succinic acid derivatives which make it taste nice and wine-y. I’m assured the results with dark chocolate and red wine are pretty tasty, though the white wine version tends to get bitter over time.
On the subject of booze, agave plants (from which tequila is made) were also the focus of some interesting research, but as a source of sweeteners rather than spirits. A group led by Mercedes López at the Center for Research and Advanced Studies of the National Polytechnic Institute in Mexico are interested in using undigestible parts of the plant as sugar substitutes for diabetic or obese people. Their work focussed on agavins – long chains of fructose sugar that aren’t digested. Agavins (not to be confused with agave syrup, which is rich in fructose monomers) taste much less sweeter than sugar, but López’s group have found some evidence they can help reduce cravings and regulate blood sugar – they found that mice given agavins in their water ate less food and lost weight compared with control groups. Their blood sugar was also lower than those given sugars like glucose and fructose, or the artificial sweetener aspartame. These initial results look promising, but more needs to be done to explore agavins’ potential, and their neutral taste is an obvious limitation.