The first thing that comes into our minds when we hear the word “garlic” is a medicinal herb that has been used since primitive times right up to the modern era whose benefits have been observed and scientifically proven. Records from the past indicate that garlic have been used for several reasons such as diuretic, digestive aid, antibiotic, anti-parasitic, infections and a wide variety of ailments. The good news is that the long history of the use of garlic in various studies have not revealed any credible adverse biological effects. Scientists have reported that each clove of garlic contains up to more than 400 beneficial compounds that are found within the oil. The key compound in garlic is known to be allicin which contributes to the characteristic flavour and taste of garlic and is one of the most potent antioxidants from the plant kingdom. It is found that the enzyme called allinase present in each bulb of garlic combines with allinin to form the active compound allicin which possesses the health enhancing properties and at the same time gives garlic its distinctive odour.
Garlic is known to be rich in manganese, calcium, phosphorus, selenium, and vitamins B6 and C, so it is beneficial for our bones and thyroid gland. Furthermore, garlic also assists the human body in getting rid of heavy metals, such as lead, mercury, cadmium, and arsenic. It is believed that garlic has several health benefits such as reducing the levels of homocysteine in the blood, boosting circulation via the increased production of hydrogen sulphide, stimulating the white blood cell activity, improving cardiovascular health and stabilizing the blood glucose levels due to its ability to enhance insulin production.
The benefits mentioned above apply to white garlic (Allium sativum L.), which is also known as fresh garlic. However, in the recent times, there has been an increased attention being paid to black garlic due to the fact that white garlic demonstrates an intense taste and smell that makes it difficult for most people to appreciate it. Thus it is important to know how white garlic becomes black garlic and what the health benefits of black garlic are.
In the actual fact, black garlic is produced when white garlic is subjected to the fermentation process at a high temperature under high humidity. This results in the formation of black garlic which has a sweet taste and a soft, jelly-like texture that is more palatable and appealing to most individuals. The distinct black colour comes from the production of a compound called melanoidin. The duration of the fermentation differs and depends on cultures, manufacturers and purposes. Many researchers believe that the production of black garlic is not a fermentation process as it does not involve microorganisms – specifically, enzymatic breakdown and the Maillard Reaction are responsible for the caramelization of the sugars, dark colour and deep, complex flavor profile.
In comparison with fresh garlic, black garlic does not produce the strong off-flavour and pungent odour due to its reduced amount of allicin, which is converted into antioxidant compounds such as bioactive alkaloids and flavonoid compounds during the fermentation process. The enhanced bioactivity of black garlic as compared to fresh garlic is due to the changes of the physicochemical properties. Studies have revealed that black garlic exhibits various functions such as antioxidation, antiallergic, antidiabetes, anti-obesity, anti-inflammation, anticarcinogenic and hepatoprotective effects.
In addition, black garlic contains higher amounts of a very specific compound called S-Allycysteine (SAC) as compared to fresh garlic which is water soluble and hence absorbed easily within the body. SAC is known to help with the absorption of allicin and is thought to help lower cholesterol and decrease the risk of cancer. As far as the antioxidant levels are concerned, black garlic demonstrates significantly much higher antioxidant activity as compared with white garlic.
Thus it can be concluded that black garlic exhibits several advantages as compared to white garlic. Due to the fact that garlic has been consumed for a long time in the human society and has been identified as a safe food substance, there will be no constraints for the further exploration of black garlic to be produced as a functional food or food supplement.
ASSOC. PROF. DR. HARESH KUMAR KANTILAL
Assoc. Prof. Dr. Haresh Kumar Kantilal is an expert in areas of research in microbiology, medical science and nutrition.
An associate professor at the International Medical University Malaysia (IMU)
Conducted numerous health talks and workshops on health topics across Malaysia, Singapore and Thailand and also has published both local and international journals.