Why som tam is pounded

Chopped vs. pounded: which bites harder? Som tam, Isan’s papaya salad, is named for pounding: som means sour, tam means pound. Garlic, chilli, papaya and lime are all pounded together. Inside each garlic cell, an enzyme and its partner are kept apart. Burst the cell and they meet: in seconds, they make allicin, garlic’s sharp bite. A knife opens the cells it cuts. A pestle bursts far more. Food chemists measured both: crushed garlic held more allicin than sliced. We tell you everything you need to know about Bangkok. Follow for more!

Som tam’s name means “sour” and “pound”. Pounding matters: garlic makes its sharp allicin only when its cells break, as an enzyme kept apart from its partner meets it within seconds, and a pestle bursts far more cells than a knife. Measured, crushed garlic held more allicin than sliced.

• Som tam (ส้มตำ) is named for how it is made: som means sour and tam means to pound with a pestle. The Royal Institute Dictionary defines it as papaya pounded and mixed with garlic, chilli, lime and dried shrimp.
• In an intact garlic clove, the enzyme alliinase is kept in each cell’s vacuole and its partner, alliin, in the cytoplasm. When cells are crushed or cut, the two meet and within seconds make allicin, the main source of fresh crushed garlic’s smell (Borlinghaus et al., 2021; Wu et al., 2026).
• Cutting gives the enzyme some access; crushing disrupts the cells more thoroughly, so more allicin forms (Wu et al., 2026).
• In a 2025 study that measured garlic prepared different ways, fresh crushed garlic held more allicin than fresh sliced garlic (Rababah et al., 2025).
• Som tam is a staple of Isan, Thailand’s northeast (Tourism Authority of Thailand, 2024).

Behind the Dish
We tell you everything you need to know about Bangkok. Follow for more!

Sources:
– The Royal Society of Thailand: Royal Institute Dictionary (พจนานุกรมฉบับราชบัณฑิตยสถาน), entries ส้มตำ, ส้ม, ตำ, ครกกะเบือ and สากกะเบือ: https://dictionary.orst.go.th/
– Borlinghaus et al. (2021): Allicin, the Odor of Freshly Crushed Garlic – A Review of Recent Progress in Understanding Allicin’s Effects on Cells. Molecules 26(6):1505: https://pmc.ncbi.nlm.nih.gov/articles/PMC8001868/
– Wu, Dong, Sun and Chen (2026): Recent advances in sulfur-containing flavors of garlic (Allium sativum L.) – formation mechanisms, controlling factors and innovative processing technologies. Food Chemistry: X 36:103886: https://pmc.ncbi.nlm.nih.gov/articles/PMC13144594/
– Rababah et al. (2025): Fresh crushed garlic exhibits superior allicin and pyruvic acid stability, while fresh sliced garlic leads in phenolic and antioxidant content. Applied Food Research 5(1):100850: https://doi.org/10.1016/j.afres.2025.100850
– TAT Newsroom (4 November 2024): Isan Cuisine Goes Gourmet – Traditional Flavours Meet Modern Innovation: https://www.tatnews.org/2024/11/isan-cuisine-goes-gourmet-traditional-flavours-meet-modern-innovation/

Facts and sources: https://soibysoi.com/episodes/why-som-tam-is-pounded

Illustrations: the garlic cell, the enzyme and allicin are drawn as characters, not to scale.
General information. Rules, prices and opening hours change: check them before you go.
All music and sound are original, made for the channel.
The narrator’s voice is AI-generated.

#bangkok #thailand #bangkoklife #thaifood