So, let's say you're a food scientist and you want to measure the strength of a batch of garlic. There are procedures for these things of course, and according to a new article in the journal Analyst this is what you'd do:
In the food industry garlic batches are frequently investigated by organoleptic testing using a trained panel of human experts. One method is based upon the dilution of garlic in sour cream followed by taste testing; repeated testing can be used in order to monitor the stability of garlic during long-term storage.
I can't help imagining one of these guys out on a first date, "What do I do? I'm a nationally recognized garlic tasting expert," he says. "That explains a lot," she responds.
In any case, this particular sensory job -- and screwball romantic comedy setup -- may soon be endangered. Oxford chemists report in that Analyst journal article that they've come up with a "simple but sensitive technique" for determining the strength of garlic that would eliminate the human tastetesters.
They take the garlic in puree form and add it to a solution of sodium bromide, a well-known sedative with some interesting chemical properties. Then, they toss some carbon electrodes in. The sodium bromide interacts with the molecules that make garlic garlicky (mostly a sulfurous compound called diallyldisulﬁde) to generate bromine, which after a couple more chemical jumps creates bromide that reoxidizes producing a current at the electrode. It turns out that the stronger the garlic, the greater the voltage generated.
Here's a plot they made measuring Spanish garlic (red) against Chinese garlic(green) and a control (blue):
The scientists, led by Richard Compton, say that the new technique could be helpful in "monitoring the garlic content of medicinal supplements, batch-to-batch variation, and the stability of garlic during storage."
All that remains is to quantify precisely how much garlic (or diallyldisulﬁde) you need to ward off a vampire.