###### Abstract  
Garlic consumption is a well-known cause of unpleasant breath and body odour, with volatile organosulfur compounds, such as diallyl disulfide (DADS) and allyl methyl sulfide (AMS) responsible for the characteristic odour. Certain foods that are rich in polyphenols (PPs) and polyphenol oxidase (PPO) are known to deodorise garlic breath. However, no study into garlic body odour has been reported owing to the very low amounts of emitted volatile organosulfur compounds. Herein, we aimed to demonstrate the effects of ingesting natural food additives rich in both PPs and PPO on the emissions of skin-derived DADS and AMS using a passive flux sampler in conjunction with gas chromatography-mass spectrometry. Three healthy male subjects were subjected to garlic-consumption testing, with all subjects commonly observed to exhibit remarkably higher dermal DADS- and AMS-emission fluxes after consuming 45 g of cooked garlic, which then gradually decreased toward their initial baseline levels. In comparison, remarkably lower emission fluxes of both organosulfur compounds were observed after consuming a natural food additive following garlic consumption in a dose-dependent manner. The optimal amount of ingested natural food additive required to reduce garlic body odour was found to be 1-2 g. Considering the metabolic pathway associated with garlic-derived sulfur compounds and elimination reactions involving PPs and PPO, allyl mercaptan is likely to be a key substance involved in reducing garlic body odour through the ingestion of natural food additives. garlic; diallyl disulfide; allyl methyl sulfide; ally mercaptan; natural food additive; phenolic compounds; polyphenol oxidase +
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which has a very low odour threshold of 0.22 ppb, is a volatile organosulfur compound produced through the metabolism of allicin [20]. DADS is subsequently metabolised into other compounds such as AMS, which has a very low odour threshold of 0.14 ppb [20]. AMS is also formed via the rapid methylation of allylmercapaptan (2-propene-1-thiol) [16; 17]. While the excretion of these compounds through exhaled air and the skin surface is a natural phenomenon, the odour of garlic can adversely affect interpersonal relationships; consequently, developing methods for its deodorisation is imperative. Ingesting various fruits and vegetables has been shown to successfully lower the levels of the abovementioned volatiles both in vitro and in vivo because they contain polyphenols (PPs), polyphenol oxidase (PPO), and reducing agents (reductases) [21; 22]. Polyphenols are naturally occurring compounds that are characterised by the presence of multiple phenolic functional groups. PPs with hydroxyl groups at their ortho positions are oxidised to the corresponding \(o\)-quinones, with the rate of the reaction enhanced by PPO [21; 22]. \(o\)-Quinones bind thiols and eliminate them by forming conjugates. Disulfides are degraded by reductases to the corresponding thiols which are also removed by \(o\)-quinones. The resulting conjugates are either odourless or have different odours; consequently, garlic breath can be deodorised by ingesting foods rich in both PPs and PPO [16; 21; 22]. [PERSON] and [PERSON] [16] demonstrated that the levels of several organosulfur compounds in the exhaled breath of subjects who chewed 3 g of garlic cloves were reduced by apple, lettuce, mint leaves, and green tea, and elucidated the roles played by PPs and PPO in deodorising such garlic-associated chemicals. However, to the best of our knowledge, how ingesting foods rich in both PPs and PPO affect the deodorisation of garlic body odour associated with trace amounts of dermal emissions has not been reported. Body odour comprises a mixture of volatile organic and inorganic compounds that emanate from the skin surface that are collectively known as human skin gas [23; 24; 25].