High cholesterol oxidation in pickled mackerel (Rastrelliger kanagurta) from Sri Lanka

Abstract

AbstractTraditional mode of preservation of fatty fish in most countries is either by smoking or pickling. Mackerel is a commonly used fatty fish in the preparation of “jaadi”, a locally prepared pickled fish product in Sri Lanka produced especially in the glut season. The aim of this study was to assess the formation of cholesterol oxidation products (COPs) during storage time during 18 wk in traditionally preserved mackerel. The most common COPs were quantified and identified by GC and GC‐MS, respectively. Total cholesterol and COPs ranged from 20 to 113 mg/100 g sample and from 0.2 to 3.8 mg/100 g sample, respectively. The content of COPs increased up to 6 wk and gradually decreased during the storage. The formation of COPs is low until week 4 of storage of jaadi. Between week 4 and 6 of storage the formation of COPs reaches its maximum level and then decreases during storage. Regular consumption of this pickled fish can be a source of considerable amounts of COPs in the diet of the local population in Sri Lanka.Practical applications: Cleaned mackerel (Rastrelliger kanagurta) covered with sun‐dried salt powder and a paste of sun‐dried Garcinia (Garcinia cambogia) fruit locally known as “goraka” is used to produce jaadi in Sri Lanka. Garcinia is a traditional commodity used for fish preservation and cooking, probably due to its antioxidant and antimicrobial properties. The results of this preliminary study could be useful in the future to increase the stability of preserved mackerel.