14 DAY TRIAL // UK scientists have developed a sensor that can determine the strength of garlic, a very interesting invention for the food industry and apparently other domains too.
The inventor is Richard Compton, who along with his team from the University of Oxford, have made an electrochemical sensor that can detect the amount of diallylsulfides in garlic – larger amounts of diallylsulfides mean the garlic has a stronger flavor.
This sensor works by suspending garlic puree samples in a solution containing bromide ions, which is analyzed voltammetrically, causing the electrogenerated bromine to react with diallylsulfides and regenerate bromide.
The entire process gives an increase in peak current, thus quantifying the response.
Eric Block, an expert in the chemistry of garlic from the University at Albany, US, explains that “it's interesting that bromine is selective for just the sulfur-sulfur bonds rather than also adding to the abundant carbon-carbon double bonds present in alliin, allicin, diallyl polysulfides and analogous 1-propenyl compounds, all of which are found in garlic preparations.”
Compton explains that this selectivity occurs because the time to make voltammetric measurements is much shorter than for conventional synthetic chemistry, so the bromine reacts with the di-sulfide bonds but doesn’t have enough time to add to the carbon-carbon bonds.
Still, some more profane people might ask themselves why was this research necessary and why should anyone know about it.
Compton explains that “a couple of years ago, we developed a sensor to measure the heat of chilli peppers” and “in the course of discussions with the food industry, we learned of a similar need for garlic sensing.”
Garlic is used worldwide to flavor food but its strength varies from species to species, crop to crop and source to source, RSC reports.
“The Moldovan Purple, for example, is much stronger than other varieties,” Compton says.
Currently, monitoring the strength of garlic purees for use in foods like sauces and curries is done by human tasters but this is rather a slow, unreliable method, and it has its inconvenients.
“There is an increasing need for sensors for the environment, in medicine, health care and in industry,” he adds.
“Electrochemical analysis is perfect for many analytical applications - for example, amperometric glucose sensor strips have transformed diabetics' quality of life.
“Electrochemistry has a major role to play, not least because of its sensitivity and potential for low-cost sensors.”
Kenneth Ozoemena, who studies electrochemistry and photosensitised reactions at the University of Pretoria in South Africa said that “electrochemical techniques are easier to miniaturize and cheaper compared to techniques such as chromatography.
“I am confident that this procedure will revolutionize the quality control of garlic and garlic-containing food.”