Exploring the preservation and modenisation of chilled pre-packed umai:Sarawak traditional raw fish delicacy

Umai is a popular traditional raw fish delicacy in Sarawak, consisting of thinly sliced raw fish cured in sour fruit juice mixed with other spices. Chilled pre-packed umai holds the potential to become a convenient delicacy, as it allows for direct mixing of sliced fish with the marinating sauce upon serving. This study aimed to modernize the presentation of prepackaged chilled red tilapia umai, which includes fish cutlets and marinade sauce, for market convenience. A study was conducted to extend the chill-storage life of sliced fish (Red Tilapia cutlets) through a dipping treatment in an organic acid solution. The results indicated that sliced fish frozen at -23°C for 7 days and treated with a 1.5% citric acid dipping solution exhibited the best storage quality, as evidenced by lower total aerobe and total coliform counts, as well as enhanced colour intensity. Fish muscle tissue often undergoes acid-induced denaturation within the pH range of 2 to 5. Therefore, the umai sauce was formulated to have a fixed pH value of 3.3, which met the denaturation process and sensory attributes, as well as the FDA requirements for limiting the growth of bacterial pathogens that are of greatest concern in seafood processing. Compared to commercial chilli sauce, umai sauce has significantly lower calorie and carbohydrate content, with 49.7 kcal and 8.7%, respectively, compared to 113 kcal and 24.5%.