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While renowned for its pungent aroma, powerful taste and even the mythical, legendary power to ward off vampires, garlic is enjoying a bit of a resurgence around the world. Demand is growing and enhanced by the growth of black garlic. This relatively new product is gaining a foothold in the United States because of its unique gourmet flavor and health-promoting properties.

Cultivation of garlic as a food and medicinal ingredient is centuries old. Garlic contains allicin, an antioxidant that has indications of healthful qualities, including reduced inflammation. Allicin forms by an enzymatic process when chopping or crushing garlic, but allicin is unstable and only available to the human body for a short time after it is crushed.

Production of black garlic, meanwhile, happens by processing raw garlic under high heat and humidity. The process can take weeks or even months. Fermenting raw garlic gives it a soft, chewy texture and smoky flavor that tastes very little like raw garlic.

Black garlic first gained popularity in Asia more than a decade ago. It’s valued as a food ingredient as well as natural health advocates.

The process for producing black garlic converts the allicin in garlic into S allyl cysteine (SAC), which the human body can use more readily than allicin. According to the Journal of Food and Drug Analysis, research has shown black garlic to have positive antioxidant effects. There are even claims black garlic can help with lowering blood pressure, anxiety and aid in weight loss.

Growing Garlic Interest

Minnesota boasts a surprising number of garlic farmers, although not all are pursuing black garlic. The Regional Sustainable Development Partnerships and Sustainable Farming Association wrote a joint Minnesota Department of Agriculture Specialty Crop block grant in 2017 to investigate how to increase production and market access for Minnesota-grown garlic. That work included sending a statewide survey to quantify the number of garlic producers in the state, their acreage and total production.

When survey responses were combined with farmers in the Minnesota Grown database who indicated they grow garlic, a total of more than 80 growers were identified. From this survey and data collection, acreage per enterprise ranged from approximately 0.25 acre to 5 acres. The majority of the reporting growers indicated they produce on 0.25 or less acres.

A second survey, conducted earlier this year, reassessed the growers, but those results are not yet available.

It’s a Process

Brothers Mike and Milton Riebel of the Design Shop in Mankato became interested in black garlic while working with a neighbor who grows USDA certified organic garlic. The Riebels have over 30 years of expertise in industrial biotechnology development.

“We’re always value-added thinking,” Mike Riebel says.

Because it’s a raw product, garlic has a limited shelf life. Further processing raw garlic expands that life and creates new market opportunities. This led the Riebels to explore processing alternatives, which resulted in the discovery of a process for making kimchi from South Korea.

“I was intrigued by the process, but the problem was it took three to four months to complete,” Mike Riebel says. “We looked at a different way to process that increased the performance and gave the black garlic a better taste.”

The Riebels experimented and developed their own process for creating black garlic with improved flavor, a faster processing time and higher levels of several key nutraceutical properties including polyphenols and SAC. The resulting proprietary process succeeded in speeding the black garlic process while improving the nutritional profile.

“Garlic is a super food,” Milton Riebel says. “This process amps those qualities up big time.”

Mike Riebel says whether for food or nutraceutical use, their process for making black garlic is superior to what is currently in use.

“We can make black garlic in a matter of weeks, but we hope to accelerate that to a week,” Mike Riebel explains.

Along the way, the Riebels enlisted the help of AURI staff and the Marshall laboratory. AURI Food and Nutrition Scientist Ben Swanson worked to evaluate the black garlic and test for polyphenol levels.

“When I first met with them, they handed me this black, gummy-bear looking thing and told me to pop it in my mouth,” Swanson recalls. “I thought they were crazy, but it tasted amazing. It was smoky and a little sweet. It tasted completely different than what I expected from garlic.”

Mike Riebel says he truly appreciates the support AURI provided while testing their proof of concept.

“We worked with AURI, tested the polyphenols and they guided us through the chemistry, so we better understood where we could go with it,” Mike Riebel says.

Scratching the Surface

Milton Riebel says black garlic is well known on the east and west coasts, but it’s just beginning to come into the Midwest. Black garlic did get a moment in the spotlight when the Iron Chef television cooking show featured it.

“Black garlic has been around, but not really in the mainstream,” Swanson explains. “It is trending with old word processing and taste. Black garlic could fit in nicely with the natural food trend as it offers some benefits .”

Swanson says the black garlic could have potential for use in dietary supplements, food ingredients including pizza toppings because of its smoky, semi-sweet taste. Powdered black garlic could be used in beef sticks or other processed meats because “it appears to have some anti-microbial activity to it.”

While garlic isn’t grown widely in the state, it is produced in Minnesota. If more opportunities arise, and more growers get involved, Swanson says the black garlic market has potential.

In the Market

The Design Shop’s process for developing black garlic is already in commercial use. Mike Riebel says they worked with Vision Home Products to produce Kasota Prairie Foods black garlic supplements which are available through large retailers including Amazon, Target and Wal-Mart.

Using their specialized fermentation process and integrating a freeze drying and grinding process they also developed, The Design Shop was able to produce a 100 percent pure black garlic powder. Mike Riebel says their process allows Vison Home Products to offer supplements that are free from husks, stems and fillers.

Kasota, Minnesota, farmer Dan Treinen operates Bent River Organics. Among the crops he grows is hardneck garlic, which needs to freeze so planting occurs in the fall.

Treinen has about 5,000 hardneck garlic plants in the ground on his Blue Earth County organic farm. Treinen also raises potatoes and jalapeno peppers which he markets at the Mankato farmers market and at the Garlic Festival in Hutchinson. Bent
River Organics also markets black garlic in four area stores.

“About 50 percent of the garlic I sell is black garlic,” Treinen says.

Production challenges last year reduced his garlic planting size and limited the supply of seed plants available from other growers. That’s limiting the amount of black garlic he’s able to market.

“We have to have the production to be able to push the marketing and that hasn’t been easy,” Treinen admits.

Still, Treinen recognizes there is tremendous opportunity in black garlic

“Black garlic has huge potential to grow. It’s still a product that a lot of people don’t know a lot about,” Treinen says. “People are starting to see it on television cooking shows. People are using it to make desserts or in their meals, so when I go visit stores, they all want to carry it, but I don’t have enough to really push the marketing.”

Sprouting Potential

The black garlic market is still developing. The Riebel’s already see more opportunity for the unique product to make its way into more food and nutraceutical applications.

“Especially as a powder,” Milton Riebel says, “because it’s easier to integrate into other products. We’re very interested in coming up with additional uses.”

Mike Riebel believes there are multiple potential application and product development opportunities for the processed black garlic.

“It would be a natural fit with cheese or meats,” Mike Riebel says. “We’ve worked with food companies testing black garlic as a preservative. We’ve looked at freeze drying it to add as flavoring. With its antimicrobial qualities it could be mixed with cheese for both functionality and flavor.”

Black garlic could be just the beginning. Based on how test market works out, Mike Riebel says the Design Shop is interested in working with other crops like camelina, chokecherry or other plants high in polyphenols.

“There are a lot of specialty crops that could be processed for nutraceutical ingredients,” Mike Riebel adds.