Som-fak

A Thai fish cake with several local names

Som-fak is a sour fermented fish cake made from freshwater fish. JIRCAS records Som-fak as a northeastern name, Plaa-fak in the north, Plaa-mak in the east and Fak-som in parts of the northeast. Those names describe a regional vocabulary, not one claimed point of origin.

The fish is minced and kneaded with cooked rice, garlic and salt until the mixture gels into a sticky paste. It is divided into small portions and wrapped in banana leaves or plastic sheet. The finished cake is slightly sour and salty, firm and elastic. Its colour can vary with the fish species and how completely blood is removed.

Fish and measured proportions

The JIRCAS entry lists ten fish commonly used: Channa micropeltes (Cha-do), Kryptopterus bleekeri (Neua-orn), Notopterus borneensis (Sa-tue), N. chitala (Kraai), N. notopterus (Sa-laad), Pangasius hypophthalmus (Sa-waai), P. larnaudi (Tay-poh), Probarbus jullieni (Yee-sok), Wallagonia attu (Kao) and W. miostoma (Kao-dam). The record names options rather than one interchangeable fish; it does not give species-specific batches.

The ingredient ratios are recorded as printed: fish to rice 6:1, garlic 20:1 and salt 20:1. The page does not state whether the ratios are by weight or volume, and it does not spell out the direction for the garlic and salt figures. A batch size and finished yield are also absent. These gaps prevent exact scaling.

From fillet to wrapped portions

Filleting removes skin and blood before the flesh is pressed in a cloth bag to squeeze out water. For thin-bodied fish such as Plaa-kraai and Plaa-sa-laad, the flesh may be scraped from the skin instead. Minced fish is then kneaded with cooked rice, garlic and salt until a sticky gel forms.

The mixture is divided into small portions and wrapped tightly in banana leaves or plastic sheet. The JIRCAS method gives a fermentation period of 3–5 days but does not state temperature or a measured completion point. It describes shrinkage and some liquid leakage during fermentation. Too little salt is associated in the account with rapid acidity, poor maturation, an unacceptable fishy odour and a soft, soggy texture; these are quality observations, not safety controls.

Serving and safety limits

Som-fak is served with lettuce, ginger, shallots, chilli and roasted peanuts. Another described serving is grilled in banana leaves with rice. The account provides no grill temperature, cooking duration or finished internal temperature, so this variation is not a measured kill step.

The source gives a two-week storage-life field but its method says to eat the product within a few days. Neither statement names storage conditions. The record therefore gives no household storage instruction.

FDA guidance treats parasites in uncooked or undercooked seafood as a potential hazard and notes that freshwater fish may carry trematode hazards. It also states that brining and pickling may reduce parasite hazards without eliminating them. This general seafood guidance does not assess each of the fish species listed for Som-fak or validate its fermentation method. No product-specific parasite control, pathogen-reduction result, measured acidification endpoint or storage plan is supplied.