Introduction

Garlic (Allium sativum L.)  has long been used as both a culinary seasoning and medicinal herb. However, excessive consumption and application of fresh garlic in foods and medicines are limited due to its characteristic odor of the breath and skin, spicy flavor, occasional allergic reactions, toxicity, and tendency to cause an upset stomach (1). black garlic benefits are anti-inflammatory, antidiabetic, protects the heart and liver.

How to make a black garlic

Black garlic (Allium sativum L.) is a kind of deep-processed food made of raw garlic under high temperatures (70-80°C) and humidity for 1-3 months without additives, causing the garlic to turn black because of the browning compounds produced.  Through this ripening process, bioactive compounds are also newly formed. This altered in black garlic-like total polyphenol content and antioxidant capacity increase during the black garlic process. Black garlic has a sweet-sour taste with a balsamic touch that reminds us of raisins, which contain water-soluble compounds, thus it lacks toxicity and has no peculiar garlic smell and taste of raw garlic (2).

Health Benefits of Black garlic

Black garlic benefits are revealed through various pharmacological functions, including antioxidant, anti-inflammatory, anticancer, antidiabetic, anti-allergic, hypolipidemic, cardiac, and hepatoprotective. Let’s take to look at some of these properties.

1. Help to lose weight

Intake of aged black garlic helps to reduce caloric/food intake, decrease fat absorption by the breakdown of fats, and release it in the blood thus preventing gain weight (3,4).

2. Black garlic helps to prevent inflammation

The person who is suffering from contact dermatitis can consume or apply aged black garlic (high content of phenolic compounds and flavonoids) which suppresses inflammation due to their antiseptic and anti-allergic properties thus treating contact dermatitis (5).

3. Improve Cognitive function

Black garlic supplementation improves both short-term and long-term memories in elderly people by minimizing the inflammation in the brain thus helping to prevent cognitive conditions like dementia, Alzheimer’s disease, and Parkinson’s disease (6, 7).

4. Black garlic is best for heart function in patients with coronary heart disease

Intake of black garlic improves blood circulation in the treatment of coronary heart disease patients. Black garlic combined with conventional treatment improves heart function, postischemic cardiac recovery, and reduced heart failure thus improving the quality of life and physical function of the patient (8, 9).

5. Healthy liver

Black garlic has the potential to block various damage caused by different chemical and alcohol effects on cell death, lipid peroxidation, oxidative stress, and inflammation thus preventing liver injury (10, 11).

6. Keep gastrointestinal healthy

Intake of black garlic stimulates contraction and relaxation of gastrointestinal muscles, enhances its gastrointestinal tract emptying, and promotes defecation thus keeping the stomach healthy (12).

7. Lower cholesterol level

Consumption of garlic improves the serum lipid profile parameters by decreasing the total lipids, cholesterol, triglycerides, and low-density lipoprotein (LDL) with a notable increase in plasma high-density lipoprotein (HDL) cholesterol level and removal through fecal excretion thus ameliorate dyslipidemia (13).

8. Treat kidney injury

Black garlic decreases urea nitrogen and creatinine in serum levels of blood as well as reactive oxygen species, which causes oxidative stress and protein oxidation. Therefore, black garlic protects against kidney damage by reducing tubular damage, including vacuolation and necrosis (14).

9. Black garlic is effective against gastric cancer

Black garlic shows a wonderful effect against gastric cancer cell growth (colon cancer) by inhibiting of cell proliferation and induction of apoptosis (15).

10. Anti-allergic properties of Black garlic

It is very effective to suppress the allergic response thus helping to prevent the development of allergic diseases such as anaphylaxis, asthma, allergic rhinitis, and inflammatory arthritis (16).

White garlic Vs. Black garlic

1. Improve taste and nutritional value

Black garlic contains a high amount of flavonoids, pyruvate, total phenol, total mineral, free sugar, organic acids, β‐carboline, alkaloids, and protein contents with the lowest moisture content than raw garlic (17). Moreover, black garlic has a sweet and sour taste jelly-like texture, and no strong odor; with has dark brown color in comparison to fresh garlic thus black garlic retains its antioxidant capacity and abundant nutrients (18, 19).

Comparison of the nutritional value of black garlic and white garlic in amounts per 100 g.

2. Black garlic is best for diabetic people

Black garlic shows stronger antioxidant activity than raw garlic by removing harmful radicals from the body increasing plasma insulin levels or alleviating insulin resistance due to the high content of S-allylcysteine and polyphenols thus useful in preventing diabetic complications (20). Furthermore, Lactobacillus bulgaricus fermentation with black garlic improves antioxidant capacity by controlling the weight gain of gestational diabetes mellitus patients, avoiding low birth weight babies and macrosomia, and improving the birth quality of newborns (21).

3. High antimicrobial properties of black garlic than white garlic

Black garlic exerts the highest antioxidant and antimicrobial (especially against methicillin-resistant Staphylococcus aureus followed by Enterococcus faecalis, Listeria monocytogenes, Escherichia coli, and Pseudomonas aeruginosa) activities than raw garlic (22).

4. Black garlic lowers anti-inflammatory activity

Black garlic possesses less anti-inflammatory activity compared with raw garlic which is due to the presence of sugars such as galactose, glucose, fructose, and sucrose (23).

5. High antioxidant activity than white garlic

Black garlic has a 5 times higher free radical scavenging ability than fresh garlic because it contains organosulfur compounds that are produced during the aging process of garlic (24).

6. Boost immunity higher than white garlic

Black garlic has a higher ability to stimulate or boost the immune system than raw garlic because it contains a high amount of phenolic compounds which show stronger antioxidant and anticancer activities in comparison to raw garlic (25).