Urbanization has brought many changes in society worldwide which includes consumers’ lifestyles and as a result their dietary practices. Snacks have become a quick and convenient food option for consumers. People are increasingly snacking in between main meals, originally to alleviate hunger but subsequently as a mainstream meal. According to Renub Research (1) latest report India’s snack food industry consists of many Indian as well as multinational companies. The market of snack food products in India is valued at US$ 11.08 Billion in 2020 and is expected to expand with a double-digit compound annual growth rate (CAGR) of 13.24% from 2020 to 2026 (1). Indian snacks market is categorized into Chips, Extruded Snacks, Namkeen, and others in which namkeen has the highest market value share in comparison to all other segments. Namkeen is currently the dominating category in both organized and unorganized markets in which fast-moving consumer goods (FMCG) companies capture a large market for its snacks segment. However, with the arrival of nutritional snacks enriched with organic ingredients with low calorie/oil content into the Indian market, these snacks are considered a bit healthier than conventional snacks and so are preferred by a large Indian population (1). Rising consumer health awareness is increasing the adoption of value-added product alternatives with natural, organic, low-calorie, vegan, gluten-free ingredients and components which imparts functional properties. With an increase in lifestyle ailments such as diabetes and cardiovascular disease, customers want to purchase products that are not only delicious and readily available, but nutritious as well.

Herbs and spices could be useful as a functional and flavoring ingredient as well as pharmacological and therapeutic properties in snack products (2). Garlic (Allium sativum L.; Liliaceae family) is one of the most important bulb crops which is grown and used as a spice and a popular Indian traditional medicinal plant (3). Garlic’s health benefits are mostly attributed to sulfur-containing components such as allicin, S-allyl cysteine and essential bioactive elements of garlic include organosulfur composites, thiosulfates and allicin (4, 5). Garlic paste and lime are used for mouth sore, sore throat and also can be used in toothpaste to prevent dental caries (6). It is reported that garlic is a potential unique therapeutic food, helpful to manage coronavirus disease (COVID-19) infection (7, 8). This comprehensive review encompasses the various medicinal and health beneficial roles by bioactive constituents associated with essential oil, and garlic-based snack-food products.

Garlic is a vegetable species that can be categorized as a food or a medicinal herb. It is a member of the Amaryllidaceae family or genus Allium that is cultivated all over the world. Various Nutritional composition of garlic per 100 g as per United States Department of Agriculture (USDA) 2019 is given in Figure 1 (9).

Organosulfur compounds, saponins, phenolic compounds and polysaccharides are among the most common bioactive chemicals found in garlic (10). Onions are richer in protocatechuic acid than garlic, which has a high concentration of quercetin which is determined by high-performance liquid chromatography (11). Garlic bulb is reported to have total flavonoid (36.1 mg kg^–1 FW), polyphenolic compounds (12.64–22.66 mg/1 g gallic acid), antioxidant activity (9.92–40.41 mol Trolox/g) evaluated using the DPPH technique (12–14). Organosulfur compounds and their derived products are primarily responsible for the bioactive characteristics of garlic, with diallyl thiosulfonate (allicin) having the major contribution. Other major organosulfur components are diallyl sulfide (DAS), diallyl disulfide (DADS), diallyl trisulfide (DATS), E-ajoene, Z-ajoene, S-allyl-cysteine (SAC), and S-allyl-cysteine sulfoxide (alliin) (15). Various sulfur components found in garlic is given below in Figure 2 (16).

Daily dose of garlic for adults as per suggested by World Health Organization (WHO) is listed below in Table 1.

Garlic products can be categorized under different categories like garlic powder, garlic oil macerate, aged garlic extract and garlic essential oil. Description of various garlic products are elaborated in the Figure 3.

Raw garlic bulbs have an abundance of γ-glutamyl-cysteine in intact form. Alliin forms naturally from these components when stored under low temperatures. The enzyme alliinase breakdown alliin to create thiosulfinates like allicin after the garlic has undergone processing operations like chopping, chewing or crushing, or any other operations that disrupt the cell membrane. Allicin and other thiosulfinates breakdowns into DAS, diallyl trisulfide (DAT), DADS, dithiins, and ajoene very instantaneously while simultaneously γ-glutamyl-cysteine is converted to SAC by a different mechanism (18). Thiosulfinates, especially alliin is the most common precursor responsible for garlic’s flavor and these sulfur compounds are also responsible for garlic’s well-known therapeutic properties (19). Various Bioactive components produced when garlic undergoes processing are given in Figure 4.

Have studied the effects of garlic consumption on decreasing total cholesterol (TC) and low-density lipoprotein (LDL) is more pronounced with a lower dosage and longer duration, especially in individuals with cardiovascular diseases (20). Raw garlic and garlic extract in the form of oil or powder can be utilized as functional and therapeutic food. There is significant evidence that indicates preventive and therapeutic roles of garlic in improving the immune system, anti-tumor properties and antioxidant activity of garlic protects the body against free radicals (21, 22). Human health has been found to benefit from a balanced diet rich in functional foods prepared with garlic. Garlic can alter blood anticoagulant levels and boost the activity of various organs in the body mainly of respiratory and digestive systems (23). According to evidence from preclinical investigations and clinical trials, garlic consumption appears to have a significant impact on antihypertensive (24), antidiabetic (25), immune-modulatory (26) and hypolipidemic effects (27) and it would be highly beneficial for medical and surgical treatments (28). Garlic is reported to lower the amount of the gastrointestinal illness-causing cryptosporidiosis in immunocompromised mice and reduced inflammation (29). Garlic alone can give us over 200 unique chemicals that can help in strengthening the immune system and help fight the body against a range of ailments. Garlic’s bioactive components can be protected using encapsulation techniques (30). Under biotic and abiotic stress circumstances, garlic extract has been demonstrated to enhance crop quality and soil conditions (31). When compared to neem oil, clove oil, and tulsi oil, garlic oil is more efficient against aerobic bacteria (32). A list of health benefits associated with various types of garlic products, along with their bioactive components is given in Table 2.

Garlic contains sulfur compounds influence the activity of the enzyme family’s glutathione S-transferase (GST) which is known to detoxify carcinogens and cytochrome P450 (CYP), which is known to activate a variety of chemical carcinogens in test animals (101). Moreover, the Antioxidant activity of garlic can help with fertility by lowering the peroxidation of lipids (102). Research has also found that the antioxidant effects of garlic can minimize the toxicity of damaging medications on the testes while also increasing spermatogenesis and fertility in men (103). Garlic possesses phytoestrogens, which have a direct influence on estrogen (104). Research has revealed that ROS which linked to the development of male infertility, plays a critical role in the disruption of the spermatogenesis process i.e., diminished ability of the genital system’s and sperm’s antioxidant system (105, 106). Diallyl disulfide present in garlic, protects the sexual organs by reducing ROS, improving and strengthening the blood-testis barrier, and increasing blood flow in the testicles (107).

Allicin and its metabolites can be identified in the blood, feces, and urine after ingesting 25 g of raw garlic which is responsible for most of the therapeutic activity and it is converted to allyl-mercaptan almost immediately under an enzyme-inhibiting gastrointestinal environment (108). According to studies conducted on raw garlic and preparation products, the primary sulfur-containing groups display varying bioavailability between raw garlic and various garlic formulations like water-soluble organo-sulfur compound SAMC has anti-oxidant properties which inhibits cell proliferation, boosts apoptosis in cancer cell lines (109) and SAC which has a blockage of nitrosamine generation and bioactive whereas oil soluble organo-sulfur compound i.e., allicin has suppressed the proliferation of cancer cells, increased apoptosis by activation of caspases and diallyl-disulfide inhibit Colon cancer by suppressing the growth of neoplastic Canine Mammary Tumor cell (CMT-13) and N acetyltransferase (10, 110, 111). The higher bioavailability of allicin (the main bioactive compound of garlic), allyl methyl sulfide in garlic-based foods as compared to crushed raw garlic (112) and higher bioavailability of allicin in enteric tablets was more than in garlic capsules. At body temperature cystine which is released from protein diet interacts with allicin in gastrointestinal tract (GI) tract to generate two S-allylmercaptocysteine (SAMC) derivatives (113). Allicin’s secondary metabolites, such as E ajoene, 2-ethenyl-4-H1, 3-dithiin, and DADS, can be found in the blood and urine after the metabolism of allicin (114). The mechanism of action of various phytoconstituents in garlic as it passes through the gastrointestinal tract is given in Figure 6.

Garlic which has medicinally chemicals compounds primarily γ-l-glutamyl-l-cysteine, is found in mature garlic bulbs (115). The amino acid alliin, which is an alkyl derivative of cysteine alkyl sulfoxide, is the major component in whole garlic bulbs. The enzyme alliinase is released when tissues are crushed, chewing that converts cytosolic cysteine sulfoxides (alliin) into thiosulfinates (Figure 7). These substances are smelly, volatile and reactive (18, 116).

Garlic oil (GO) which is utilized in many medical garlic products, is created by steam distilling mashed garlic and creating organo-sulfur compounds and yields between 0.09 and 0.35 % of the fresh weight (117). Tocmo et al. (118) assert that DATS is more prevalent in fresh GO than commercial oils, with the number of DADS varying depending on the temperature or duration of the extraction process. The amount and number of constituents in essential oils vary, but in all investigations reported diallyl disulfide is almost always the main ingredient followed by allyl disulfide, allyl trisulfide (119). These substances are the transformation products from allicin, a substance with significant medicinal value because it has a wide range of biological activities. However, allicin is also the most unstable of all the thiosulfinates produced by the vascular enzyme allinase, which is released after tissue damage (120). GO is particularly a good source of organosulfur compounds, primarily allyl disulfide (28.4%), allyl trisulfide (22.8%), allyl-1-propenyl disulfide (8.2%), allyl methyl trisulfide (6.7%), and diallyl tetrasulfide (6.5%) (121). These compounds have potent antioxidant, antibacterial, antithrombotic, and immunomodulatory properties as well as hypotension, anticancer and antimicrobial effects (121) (Figure 8).

The U.S. Food and Drug Administration has classified garlic as “Generally regarded as safe (GRAS)” for food and flavoring ingredients, although there are severe consequences of reported acute and chronic toxicity on its excessive consumption. Allicin, a substance abundant in garlic, when consumed in large doses, can be hazardous to the liver (139). Additionally, the abundance of different sulfuryl derivatives in essential oils may worsen its harmful effect such as throat and mouth burning, stomach ulcers, nausea, vomiting, erythematous mucosa which is characterized by redness and inflammation in the gas mucosa layer as well as hyphaemia, bleeding gums and potentially irreversible eyesight loss (121). The organosulfur compounds having possible toxicity i.e., endotoxin-induced systemic inflammation and intestinal damage is reported by a study (140).

Garlic is used in both cooking and medicine. Compelling evidence reports its possess anti-inflammatory, anti-hypertensive, anti-anemic, anti-hyperlipidemic, anticarcinogenic, antiaggregant, antioxidant, antiviral, anti-microbial, anti-fungal, and antiviral activities. Increased shelf life of all examined goods was enhanced by using fresh garlic and ready-to-eat garlic products with antioxidant properties that reduced the amount of free radical-scavenging activity and increase total polyphenol content (141). These beneficial components in garlic could be used to great success in the creation of foods and nutritional supplements for young children, pregnant or nursing women, cancer and cardiovascular death rates, as well as severe side events and morbidity after garlic therapy.

The possibility of interactions between herbal medicines and conventional pharmaceuticals is a significant safety concern with the increased usage of herbs. Herb-drug interactions have the same mechanisms as drug-drug interactions and can act both pharmacokinetic (changes in plasma drug concentration) and pharmacodynamic (drugs interact at receptors on target organs) levels (146). The induction (or inhibition) of hepatic and intestinal drug-metabolizing enzymes, specifically cytochrome P450 (CYP) and/or drug transporters like P-glycoprotein, as well as pharmacokinetic interactions, which have been more thoroughly studied, maybe the cause of the altered drug concentrations caused by co-administration of herbs (147). Clinical research indicates that ingesting garlic may cause pharmacodynamic interactions that could pose a risk to individuals on conventional medications, especially in those taking antihypertensive, anticoagulant, or hypoglycemic medications. Garlic interacts with antihypertensive medications that are prescribed to control blood pressure. Additionally, it interacts with Saquinavir and low therapeutic properties the amount of medication in the blood and circulatory system (148). Garlic enhances the effects of drugs that decrease cholesterol and lower blood pressure in the body (149). Garlic’s impact on hypoglycemic medications increases the likelihood of hypoglycemia, among other drug interactions (150). Anticoagulants including heparin, warfarin, and aspirin interact with the garlic plant to increase the risk of bleeding (149). Additionally, garlic increases the fibrinolytic and platelet-activating anti-factor activities in anesthesia (148).

Garlic is a aromatic herbaceous plant that is used as an essential ingredient in ready-to-eat snacks foods to enhance the flavor of the product and also improve the therapeutic, functional value and shelf life. Additionally, garlic is rich in organosulfur and flavonoid compounds which are effective in the management of wide range of health disorders, and may be a useful remedy in the prevention of COVID-19. Snacks can be nutritionally enriched by incorporating garlic extracts. The multifunctional therapeutic role of Garlic is attributed to its rich phytocompounds and their several bioactive properties including anti-microbial, anti-inflammatory, anti-hypertensive, anticarcinogenic, antifungal, antiviral, and antioxidant. More standard experiments and clinical studies are needed to back up the claims of garlic in the treatment and prevention of various diseases.

TV, PD, AA, and RS: conceptualization, methodology, investigation, data collection, and writing—original manuscript. SR, K-TC, AC, and RS: editing and proofreading. RS and TV: supervision. All authors approved submission of the final manuscript.