Black Garlic: How It’s Made, What It Tastes Like and What the Research Shows

Black garlic tastes nothing like raw garlic. It’s sweet, tangy and molasses-like, with almost none of garlic’s sharp bite. It starts as ordinary garlic, Allium sativum, held for days at warm temperatures and high humidity until the cloves go black, soft and sweet. Nothing’s added, and though it’s often sold as “fermented,” the darkening comes from the Maillard reaction. Slice it over pizza, mash it into butter, or whisk it into a pan sauce where that molasses note fits.

At a glance

How black garlic is made

A 2017 review in Molecules describes black garlic as fresh garlic kept in a temperature- and humidity-controlled room for more than 10 days, with no other treatment or additives. Production usually runs between 40 and 90°C at 60 to 90% relative humidity. One example schedule in the review steps the heat down: two days at 90°C, four at 80°C, four at 60°C and one at 40°C.¹ A Korean producer profiled in the South China Morning Post keeps the details secret, but ages the garlic with hot air for 14½ days, dries it naturally for about 40 hours, then ages it again for 30 to 50 hours.²

Is it fermented?

It’s often sold as “fermented.” But the process the review describes is heat and humidity alone, with nothing else added, and it credits the dark brown color to a Maillard reaction set off by heating. There’s no microbial step in its account. The review’s own term is “aged black garlic.”¹

What changes in the clove

• Color. The white to pale yellow clove turns dark brown and eventually black.
• Sugars. Total and reducing sugars are higher in black garlic than in fresh.
• Allicin. Black garlic has less allicin than fresh garlic. In raw garlic, allicin forms within 10 to 60 seconds of crushing.³
• S-allyl cysteine (SAC). The review reports SAC four to eight times higher after aging. In the measurements it cites, fresh garlic held about 2.2-2.3 mg per 100 g and black garlic about 9.8-11.4 mg per 100 g, depending on the method.¹

Flavor and texture

Black garlic is sweet and sour, with a jelly-like texture and no strong smell. The South China Morning Post calls the flavor creamy and molasses-like, a little sweet as well as savory and tangy, with a texture like soft, jelly-like fruit. It doesn’t have the very strong flavor of normal garlic.²

Black garlic often gets called rich in umami. None of the sources we checked measured glutamate or other umami compounds, so take that as a taste impression.

Where it comes from

Garlic itself is ancient. Old medical texts from Egypt, Greece, Rome, China and India mention it. Black garlic is another story. The Molecules review only says it was recently introduced to Asian markets as a functional food.¹ The South China Morning Post reports that Scott Kim started making black garlic in South Korea in 2004, and that he didn’t invent the method.²

Past that, the history gets murky. Claims that black garlic is a centuries-old Korean medicine, or traditional elsewhere in Asia, couldn’t be traced to any source we opened.

How to use black garlic

You use black garlic differently from fresh, since it brings sweetness and depth, not heat.

• Mash it into a paste with oil or butter and spread it on bread, or stir it into sauces, dressings and mayonnaise.
• Slice it thin over pizza, salads, rice bowls or cheese plates.
• Whisk it into pan sauces and glazes for meat or roasted vegetables, where the molasses note fits.
• Use the powder in rubs and seasoning blends. See black garlic powder uses.

It won’t replace fresh garlic one for one in a dish that depends on garlic’s sharpness. For that, see fresh garlic substitutes.

Health research

Most black garlic research is lab and animal work. The Molecules review notes that its therapeutic effects have been shown in many types of cells and animal models, and that its components haven’t been fully analyzed yet.¹ Here’s what the review reports:

So black garlic isn’t just “stronger” garlic. It scores higher on some antioxidant tests and lower on several other activities. We’re not claiming it prevents or treats any disease. For what NIH says about garlic in general, supplements included, see the garlic profile. NCCIH’s summary covers garlic, not black garlic specifically.⁴

Buying and storage

Good black garlic is evenly dark, soft and moist. We found no regulator or standards body giving a shelf life, so go by the package date and keep opened product sealed. For black garlic powder, check the ingredient list for anything besides garlic.

Related pages

• Garlic and garlic powder
• Garlic powder vs. garlic
• Too much garlic