Source-dependent compositional changes in coconut flavoured liquid smoke and its application in traditional Indian...

Smoking is an age-old food preservation method. Intense smoking results in deposition of carcinogenic polycyclic aromatic hydrocarbons (PAH) in food. Replacing traditional smoking practices with application of liquid smoke or smoke flavouring is proven to reduce the PAH content without adversely affecting flavour of the products. This study explores source-dependant variations in composition of a coconut-flavoured liquid smoke. Liquid smoke produced from coconut husk (CH), coconut fibre (CF) and coconut fibre powder (CP) was analysed for total phenolic content, total carbonyls, titratable acidity, pH and PAH content. Resultant liquid smokes were also compared a commercial liquid smoke (CL) for composition. Total phenolic content in the liquid smokes ranged from 1518 ± 184 (CH), 1037 ± 110 (CF), 834 ± 48.23(CP) and 20047 ± 193 mg L^-1 (CL). Commercial liquid smoke showed highest total PAH content 215 ± 15.45 ng ml^-1 followed by 8.23 ± 1.47 (CP), 7.22 ± 1.44 (CF) and 0.64 ± 0.13 ng m^-1 (CH). Further, process parameters for producing 'masmin' - a popular traditional smoked and dried ready-to-eat product - by replacing traditional smoking practices with liquid smoking were standardised using Response Surface Methodology. Spraying cooked skipjack tuna (Katsuwonus pelamis) loins with coconut husk liquid smoke containing 4% salt for 155 min at flow rate of 3 L hr^-1 and chamber temperature of 60°C was found to give the product a matching flavour with traditional masmin.