Garlic discovery could lead to “more potent” varieties and better controls for flavor

06 Aug 2020 --- A new discovery could lead to a more potent garlic that could boost flavor. A team of Virginia Tech researchers in the US have discovered a further step in the metabolic process that produces the enzyme allicin, which leads to garlic’s delectable taste and aroma, a finding that upends decades of previous scientific belief. Their work could boost the malodorous – yet delicious – characteristics that garlic-lovers over the world savor.

“This information changes the whole story about how garlic could be improved or [how] we could make the compounds responsible for its unique flavor,” says Hannah Valentino, a College of Agriculture and Life Sciences Ph.D. candidate. “This could lead to a new strain of garlic that would produce more flavor.”

Garlic is one of the most heavily consumed spices worldwide and is used widely in several cuisines.A quintessential ingredient?
Speaking to FoodIngredientsFirst, she says garlic is one of the most heavily consumed spices worldwide being a quintessential ingredient in several cuisines. “The compound allicin and its secondary compounds are key components of garlic’s distinct flavor. These compounds are also what causes bad breath after eating garlicky foods.”

Commenting on the findings and what this might mean for the future, Valentino adds, “it opens the door for scientists to better predict the production of allicin through the expression levels of a flavin-containing monooxygenase (FMO) produced by A. sativum (AsFMO) which can be translated into more pungent bulbs.”

Garlic could be sold as strong or weak, depending on consumer preferences. This also opens the door for buyers looking to pick garlic based on its might and better control of production and more consistent crops, which would significantly help farmers. 

Peeling back the layers
When Valentino and her team set out to test the generally accepted biological process that creates allicin, they found it just didn’t happen. That’s when the team of researchers set out to discover what was really happening in garlic.

As they peeled back the layers, they realized there was no fuel to power the previously accepted biological process that created allicin.

“By using rational design, [Valentino] found a potential substrate,” says Pablo Sobrado, Professor of biochemistry at the College of Agriculture and Life Sciences and a member of the research team. “This is significant because finding the metabolic pathway and understanding how the enzyme actually works and its structure gives us a blueprint of how allicin is created during biosynthesis.”Valentino (left) and Sobrado (right) are conducting research that lays the foundation for a future in which buyers can choose garlic based on its strength and flavor profile.

Valentino and the team – which included undergraduate students – worked in the Sobrado Lab in the Fralin Life Sciences Institute directly with the substrates that comprise garlic, doing their work solely in vitro.

The researchers found that allicin, the component that gives garlic its smell and flavor, was produced by an entirely different biosynthetic process. Allyl-mercaptan reacts with flavin-containing monooxygenase, which then becomes allyl-sulfenic acid.

Importantly, the allicin levels can be tested, allowing farmers to know their crops’ strength without the need for genetic engineering. Greater flavor can simply be predicted, meaning more powerful garlic could be bred or engineered.

“We have a basic understanding of the biosynthesis of allicin that it is involved in flavor and smell, but we also now understand an enzyme that we can try to modulate, or a modify, to increase or decrease the level of the flavor molecules based on these biological processes,” Sobrado says.   

The research has recently been published in The Journal of Biological Chemistry.

The researchers found that allicin, the component that gives garlic its smell and flavor, was produced by an entirely different biosynthetic process. “We are interested in further characterizing the enzyme AsFMO as well as similar enzymes in other plants, such as onions,” Valentino concludes. 

In April, FoodIngredientsFirst’s sister platform NutritionInsight reported that Pharmactive Biotech’s black garlic extract ABG10+ could help promote vascular health. According to an in vivo mice study published in the journal Nutrients, it also found that supplementation with ABG10+, which contains S-allyl-cysteine and polyphenols, could help balance lipids and decrease the risk of atherosclerosis, commonly caused by oxidative stress. 

In January, Pharmactive Biotech Products S.L. launched its new generation of aged black garlic extract for functional food applications and the culinary market, under the brand name ABG10+. The extract is obtained from fresh garlic (Allium Sativum L.) that has been aged, a process which alters the physicochemical properties of garlic resulting in enhanced antioxidant and cardioprotective properties. 

The World Health Organization highlights that although preventable through dietary intervention, cardiovascular disease remains the top-ranking cause of global deaths.

By Elizabeth Green