Shrimp paste

• belacan

  Malay — Malaysia, Singapore

  Usually sold as a firm, dried block, pressed and sometimes sun-dried after fermentation.

• terasi

  Indonesian — Indonesia

  Also written trassi. Javanese terasi may be made from small fish as well as shrimp.

• kapiกะปิ

  Thai

• mắm tôm

  Vietnamese

  A soft, wet, purple-grey paste rather than a block, and far more pungent raw; mắm ruốc is a related, drier product.

• bagoong alamang

  Tagalog

  "Bagoong" alone may mean a fermented fish paste (bagoong isda); alamang specifies the shrimp version.

• ngapi seinsa

  Burmese

  "Ngapi" alone covers fermented fish pastes as well as shrimp; the shrimp paste is one kind of ngapi.

Salty and powerfully savoury, with a funk that cooking turns into depth rather than removes.

Raw: intensely fishy, pungent and ammoniacal, enough to fill a house when toasted. Cooked into a paste: the fishiness recedes into a deep, rounded savoury smell. Analysis of commercial terasi finds sulfur compounds, short-chain fatty acids with cheesy and sweaty notes, trimethylamine and, in some products, roasted-smelling pyrazines — a mixture whose balance differs from maker to maker.

Block pastes range from pinkish-purple to dark brown; wet mắm tôm is purple-grey.

Block pastes are firm and crumbly and are toasted or dissolved; wet pastes are soft.

• Trimethylamine — The fishy, ammoniacal note of the raw paste, and the part cooking drives off.
• Short-chain fatty acids — Cheesy, sweaty and rancid notes that, in balance, read as the funk of a traditionally fermented paste.
• 2,5-Dimethylpyrazine and trimethylpyrazine — Roasted, nutty notes found in some products, which fermenting Bacillus can make without heat.(what 2,5-dimethylpyrazine is)

Toast block paste in a dry pan or in foil over a flame until it is dry and crumbly, or fry it in the paste until the oil separates. Use a little: a teaspoon seasons a curry for four. Never use it raw except in the dips made for it.

The savoury base of Southeast Asian spice pastes: Thai curry pastes, Malaysian rempah, Indonesian bumbu, Burmese curry bases. Also toasted and pounded with chilli into sambals and nam phrik, fried with greens, and cooked with pork in the Philippines. Used in small quantities; it seasons rather than flavours.

• toasting — Block paste is toasted in a dry pan or wrapped in foil over a flame before use, which drives off the sharpest fishy volatiles and deepens the savouriness. It smokes out the kitchen while it does so.
• frying — Pounded into a spice paste and fried in oil until the oil separates, which is the other way the raw smell is cooked out.
• grinding — Pounded with shallot, garlic, chilli and the rhizomes into the paste rather than used alone.

It should smell strongly and cleanly of fermented shrimp. A musty, mouldy smell or visible mould means discard it.

• Visible mould
• A musty rather than fermented smell

• Drying out and darkening with age
• Mould where a block paste has been kept damp

The coasts of mainland and maritime Southeast Asia, where fermenting small shrimp and fish with salt has long been the way the catch was preserved. No single place of origin can be named.

• Malaysia — major producer. Belacan, with Penang and Melaka well-known sources.
• Indonesia — major producer. Terasi.
• Thailand — major producer. Kapi.
• Vietnam — major producer. Mắm tôm, as a wet paste.
• Philippines — major producer. Bagoong alamang.
• Myanmar — major producer. Ngapi seinsa.

Small shrimp are netted in coastal and estuarine waters in their season and salted on landing, before they spoil.

1. Salting — The fresh shrimp are mixed with salt, which stops spoilage and draws out water.Why: To preserve the catch and select for salt-tolerant fermentation.
2. Fermentation — The salted shrimp are left to ferment, their own enzymes and salt-tolerant microbes breaking the protein down.Why: To develop the savoury depth and the characteristic smell.
3. Grinding and drying — For the block pastes — belacan, terasi, kapi — the fermented shrimp are ground, sun-dried, pressed and sometimes fermented again. Wet pastes such as mắm tôm are not dried.Why: To concentrate it into a stable, dense product.

• A block or jar from a named origin — Penang belacan, Thai kapi — bought where the cuisine is cooked.
• A strong, clean fermented smell rather than a musty one.
• No visible mould.

• Crustaceans (crustacean shellfish) — a declarable allergen in the EU and US

Salt-fermenting small shrimp and fish is an old way of preserving a seasonal catch around the coasts of Southeast Asia, and the pastes it produces became the savoury base of the region’s cooking long before any written record of them. Their written history is thin; their continuity is not.

Largely made and sold within the region, with export chiefly to diaspora markets.