Black garlic is a type of aged garlic that is colored deep brown. It was first used as a food ingredient in Asian cuisine. It is made by heating whole bulbs of garlic (Allium sativum) over the course of several weeks, a process that results in black cloves. The heat produces key intermediate compounds of the Maillard reaction giving the black garlic its color and taste. Research suggests yeast fermentation may give additional health benefits. The taste is sweet and syrupy with hints of balsamic vinegar or tamarind. Black garlic's popularity has spread around the world as it has become a sought-after ingredient used in both home-cooking and high-end cuisine.
In Korea, black garlic was developed as a health product and it is still perceived as such. It is sometimes added to energy drinks, and in Thailand is claimed to increase the consumer's longevity. In Cambodia, it's believed that black garlic can help fight flu and improve immunity and increase penile length and girth and is recommended to consume early morning before breakfast.
Black garlic is made when heads of garlic are aged under specialized conditions of heat and humidity. Bulbs are kept in a humidity-controlled environment from 80 to 90% at temperatures that range from 60 to 90 °C (140 to 190 °F) for 15 to 90 days (typically 85%, 70 °C, 40 days). There are no additives, preservatives, or burning of any kind. The enzymes that give fresh garlic its sharpness break down. Those conditions are thought to facilitate the Maillard reaction, the chemical process that produces new flavour compounds responsible for the deep taste of seared meat and fried onions. The cloves turn black and develop a sticky date-like texture.
Bacterial endophytes capable of fermentation and with a strong ability of heat resistance have been identified in common garlic and black garlic. These may have relevance to black garlic production.
In black garlic, the garlic flavor is softened such that it almost or entirely disappears depending on the length of time it is heated. Additionally, its flavor is dependent on that of the fresh garlic that was used to make it. Garlic with a higher sugar content produces a milder, more caramel-like flavor, whereas garlic with a low sugar content produces a sharper, somewhat more acidic flavor, similar in character to tomato paste. Burnt flavors may also be present if the garlic was heated for too long at too high a temperature or not long enough: during heating, the garlic turns black in color well before the full extent of its sweetness is able to develop.
Black garlic can be eaten alone, on bread, or used in soups, sauces, crushed into a mayonnaise or simply tossed into a vegetable dish. A vinaigrette can be made with black garlic, sherry vinegar, soy, a neutral oil, and Dijon mustard. Its softness increases with water content.
Unlike the vegetable from which it is made, white garlic, black garlic has a very subtle and muted flavor that is easily overpowered.
Because of its delicate and muted flavors, a considerably larger amount of black garlic must be used in comparison to white garlic in order to achieve a similar level of intensity. Additionally, black garlic cannot be used in place of white garlic. If a garlic flavor is desired in addition to the flavor of black garlic, then fresh garlic must be added.
One method to release the subtle flavors of black garlic is to knead a peeled clove between the fingers until its structure is thoroughly broken down and then to dissolve the resulting paste in a small amount of hot water. This produces a dark brown, coffee-colored suspension of the fibrous black garlic particles in a solution that carries most of its flavor, acidity, and sugar content. This liquid may then be added to foods that are otherwise neutral in flavor (like, for example, mashed potatoes) to better showcase the flavor of the black garlic.
It gained USA television attention when it was used in battle redfish on Iron Chef America, episode 11 of season 7 (on Food Network), and in an episode of Top Chef New York (on Bravo), where it was added to a sauce accompanying monkfish.
In the United Kingdom, where it made its TV debut on the BBC's Something for the Weekend cooking and lifestyle program in February 2009, farmer Mark Botwright, owner of the South West Garlic Farm, claimed to have developed a process for preserving garlic after finding a 4000-year-old Korean recipe for "black garlic".
The television show Bob's Burgers Season 5 episode 5 "Best Burger" highlights black garlic as a key ingredient for Bob and Linda's entry in a cooking competition during a food festival. Bob's "Bet It All On Black Garlic Burger" is listed in the competition as "Stupid Black Garlic Burger" by the competition's host.
Used by candidate Thomas Chisholm in Episode 7 of Season 22 of the French Top Chef as a sauce for a dessert made of autumn chanterelles.
Seven kinds of Bacillus were found from garlic and black garlic, respectively. Further studies demonstrated that the total bacteria and endophytes showed a sharp decrease firstly, followed by a rapid rise, then maintained at a certain level, and finally slowed during the black garlic processing. B. subtilis, B. methylotrophicus, and B. amyloliquefaciens were the dominant strains. The selected strains were capable of fermenting glucose, lactose, sucrose, and garlic polysaccharide to produce acid but no gas, with a strong ability of heat resistance. The results indicated that there were a certain number of garlic endophytes during the black garlic processing, and Bacillus was the dominant strains under the conventional culture-dependent methods.