What is black garlic? How heat and humidity turn a pungent ingredient mild and slightly sweet

April 27, 2026 What is black garlic? How heat and humidity turn a pungent ingredient mild and slightly sweet by Mavra Javed, The Conversation edited by Gaby Clark, reviewed by Andrew Zinin Gaby Clark scientific editor Meet our editorial team Behind our editorial process Andrew Zinin lead editor Meet our editorial team Behind our editorial process Editors' notes This article has been reviewed according to Science X's editorial process and policies. Editors have highlighted the following attributes while ensuring the content's credibility: fact-checked trusted source written by researcher(s) proofread The GIST Add as preferred source Credit: Image generated by the editorial team using AI for illustrative purposes. You may have seen black garlic appear more frequently in grocery stores, restaurants, and online recipes over the past few years. Many chefs and food writers describe it as a unique and deeply flavored ingredient. So what is black garlic, and how is it made? I noticed a growing curiosity about black garlic firsthand while presenting my food science research at a showcase at Michigan State University. Several people asked me basic questions about black garlic, like how it is made and what sets it apart from regular garlic. The ingredient's growing popularity reflects a broader interest in foods that offer both distinctive flavor and potential health benefits. Black garlic is not an ancient traditional food, but a recent innovation developed in Japan in the late 20th century. The process of making black garlic is often attributed to Japanese scientist Hamasuke Hamano, who spent a decade refining a method to make garlic more palatable before securing a patent in 2004. How is black garlic made? Black garlic is not a different type of garlic. It is made from regular garlic bulbs that have been kept under warm, humid conditions, typically in specialized chambers that maintain exact heat and humidity levels for several weeks to months. Unlike traditional fermentation, this process does not use added microorganisms. Instead, the transformation happens through a combination of heat and moisture. As the garlic is slowly heated under controlled conditions, natural chemical reactions known as Maillard reactions take place within the cloves. These reactions give black garlic its dark color and its slightly sweet, rich flavor. Producers may use different processing times, storage temperatures, and packaging materials, all of which can make the final product vary in taste and quality. Because of this variation, black garlic often doesn't taste the same across products. Texture and taste of black garlic While raw garlic has a sharp, pungent taste, black garlic typically has a milder, slightly sweet taste. The underlying chemistry is complex, but the basic idea is straightforward: Heat and humidity transform both the taste and structure of garlic. These shifts in flavor happen because the compound responsible for garlic's strong taste breaks down during the heating process. At the same time, heat-driven reactions form new compounds that contribute to a smoother and more complex flavor. The texture also changes significantly. Instead of being firm and crisp, black garlic becomes soft and almost spreadable. The heat and humidity break down the structure of garlic by softening its cell walls and altering its sugars and proteins. The reactions also reduce allicin: the compound responsible for garlic's sharp and pungent flavor. At the same time,…

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