Review on the fatty acid profile and free fatty acid of common carp (Cyprinus carpio)

Carp or ponty in Hungarian, is considered commercial freshwater fish, which is an adaptable species in both wild and cultured conditions. Carp has high nutritional value content, favorable taste, it is rich in protein, and low in saturated fat. The nutritional content in fish is composed of many chemical constituents and influenced by many factors. One of the components that its content may be different due to internal and external factors is fatty acids, which may vary depending on endogenous and exogenous factors. The endogenous or internal factors include the genetic, size, sexual maturity, and life cycle phase. While microclimate, water quality, quality of food or diet habit, and the amount of available food or starvation are considered as exogenous or environmental factors. Freshwater fish has the ability to convert essential fatty acid into long chain polyunsaturated fatty acid like AA, EPA, and DHA. Most results showed that palmitic acid and oleic acid were the dominant SFA and MUFA in carp both for wild and farmed carp in all seasons. The PUFA for wild carp was mainly dominated by DHA, while on farmed carp by LA. It confirmed that high LA content in farmed carp was related to the diet habit. The amount of lipid and FA were changed in line with the season. Even the statistical analysis showed no significant difference, but some studies showed a contrasting result. Moreover, most obtained results acknowledged that FA tends to decrease during the spawning period. The amount and composition of FA were affected by the total lipid content. The lipid must be broken down into simpler compounds such as FA or FFA for the metabolism of fish. The result of metabolism then transported into the utilising tissue and used as energy.