Pekasam from freshwater fishes including tilapia is more popular compared to marine fishes because the former is superior in flavour and texture. Undesirable ammonia smell is often associated with pekasam from marine fish. Small-sized tilapia of less than 350 g per fish is good for fermentation. The fish is gutted, cleaned and mixed with 22% sea or rock salt. After two days, the fish is mixed with
roasted rice (15%) and brown sugar (5%) and allowed to ferment for 4-5 weeks. Lactic acid bacteria will ferment the sugars to acid and reduce the pH in fish tissue from 6.5 to about 4.0-5.0 in 10-15 days. A characteristic flavour of being salty, acidic and aromatic usually develops fully after 4 weeks of fermentation. MARDI has introduced a fast fermentation method whereby the product is ready in 2-3 weeks depending on the species. Cleaned fish is mixed with 30-50% roasted rice and 5% brown sugar before being packed in a fermentation tank. A saturated brine solution is poured into the tank to submerge the fish. The fish is allowed to ferment anaerobically for 2-3 weeks. Malaysian Food Regulation 1985 requires pekasam to contain not less than 10% salt. Better packaging and presentation is necessary to promote the product widely. Low temperature storage will extend the product shelf-life to 8-12 months.
