Plaa-som (pla som)
Plaa-som is a Thai sour fish: freshwater fish salted overnight, then mixed with cooked rice and garlic and fermented for about five to seven days at ambient temperature.
Pla som, tilapia batch
Pla som from tilapia · ปลาส้มปลานิล
Thai pla som made from tilapia salted, filled with sticky rice and garlic, bagged and held at room temperature for about three to four days.
A fermented tilapia with sticky rice
Pla som is a Thai fermented fish, made by salting fish and packing it with cooked or raw sticky rice and garlic, then letting it sour. This page covers one batch shown in a Thai creator's video, made with tilapia. The video is aimed at home cooks and at making the food for sale.
The creator describes about 2.5 kg of purchased tilapia, 200 to 300 g of salt for an initial hold of 2.5 to 3 hours, and 300 to 400 g of garlic. The sticky rice weight and whether it is cooked are not given.
Filling and holding
The fish is rinsed and drained, then filled with the rice, garlic and salt. It is bagged and held at room temperature for about three to four days. The creator says weather changes the sourness of the result. The spoon sizes and some amounts are unclear in the captions.
Why this page is held
Salted fish held at room temperature for days, with no measured salt concentration, endpoint or temperature, is a botulism concern. FDA's guidance on salted and fermented fish notes that toxin can form without visible spoilage. The creator's claim that the steps prevent spoilage is not validated. The page records the batch but is not released for household use.
The existing pla som page on this site is a separate method and is not merged with this one.
History
The video presents a tilapia batch for home and sale. Its history and origin are not established.
Ingredients
Scaling: source batch only
TilapiaPurchased weight. Rinse, drain, then fill the cavity with the rice, garlic and salt mixture.
2.5 kg
Cleaned weight not given.SaltInitial salt for the 2.5 to 3 hour hold, and the filling.
250 g
200 to 300 g.Sticky riceCooked or raw state is not stated.
Weight not given.
GarlicMixed into the filling.
350 g
300 to 400 g.Method
Risks and precautions · High risk
Botulism risk in salted fish held at room temperature
FDA describes botulism hazards in fish preserved by salting, drying, pickling or fermentation, and notes that toxin may occur without visible spoilage. This batch holds the fish at room temperature for days without a validated control.
Hazard sourceQualified process validation of salt, temperature, pH endpoint and storage life before any household batch
Control sourceSourness, a smell or a good taste do not establish safety.
The creator's claim that the steps prevent spoilage is not validated.
Do not make this batch from the video without qualified review.
- Buy about 2.5 kg of tilapia, and salt it with 200 to 300 g of salt for an initial 2.5 to 3 hour hold.
- Rinse and drain the fish.
- Fill the fish with a mixture of sticky rice, garlic and salt.
- Bag the fish and hold it at room temperature for about three to four days. The creator says weather changes the sourness.
- The creator says to refrigerate leftovers. No refrigerator temperature or storage life is given.
Conditions
Fermentation3–4 days
Places
Thailand
Documented preparation · Country evidenceA Thai creator's video. The batch's own location and the origin of pla som are not established.
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Sources
เติมไขมัน ChannelMethod
วิธีทำปลาส้มปลานิล แบบละเอียดสามารถทำกินทำขายสร้างอาชีพได้2.5 kg tilapia, 200 to 300 g salt for a 2.5 to 3 hour hold, 300 to 400 g garlic, sticky rice
Rinse, drain and fill, bag, room temperature for about 3 to 4 days
U.S. Food and Drug AdministrationSafety
CPG Sec 540.650 Uneviscerated Fish Products that are Salt-cured, Dried, or Smoked (Revised)Botulism hazards in salted, dried, pickled or fermented fish; toxin without visible spoilage