Iis Rostini

Volatile components of raw Patin Catfish (Pangasius hypophthalmus) and Nile Tilapia (Oreochromis niloticus)

Volatile components are groups of compounds which could affect the aroma and acceptance of commodities. The objective of this research was to identify volatile components of two most common freshwater commodities in Indonesia which are patin catfish (Pangasius hypophthalmus) and nile tilapia (Oreochromis niloticus). The method used in this study were to detect volatile compounds using Gas Chromatography/Mass Spectrometry (GC/MS) on both fresh fish samples with Solid Phase Micro Extraction (SPME) as an initial extraction method. The volatile components analysis successfully detects and identify as many as 46 volatiles compounds in raw nile tilapia and 59 compounds were detected in raw patin catfish. Most of the detected components came from hydrocarbons, aldehydes, alcohols and ketone groups. Most of those volatile compounds detected were derived from the results of enzymatic reactions, lipid auto oxidation and various environmental influences.

Amino Acid Profile and Volatile Flavour Compounds of Raw and Steamed Patin Catfish (Pangasius hypophthalmus) and Narrow-barred Spanish Mackerel (Scomberomorus commerson)

Fish species and processing methods could affect the volatile flavour composition and amino acid profile of fishery commodity. The objectives of this study were to identify volatile components and amino acid profile of two considered predominant fish species in Indonesia which are freshwater Patin catfish (Pangasius hypophthalmus) and marine water fish, Spanish mackerel (Scomberomorus commerson). The methods used in this study were to detect volatile compounds using Gas Chromatography/Mass Spectrometry (GC/MS) on fresh and steamed of both species samples (100°C for 30 minutes) and amino acid profile were also analyzed using High Performance Liquid Chromatography (HPLC). The volatile components analysis successfully detects as much as 29 and 59 volatiles compounds in fresh and steamed Patin catfish respectively, while 37 and 102 compounds were detected in fresh and steamed Spanish mackerel samples. Most of detected components derives from hydrocarbons, aldehydes, alcohols and ketone groups which could affected by their chemical composition and resulted from various thermal involved reaction. The amino acids profile identification results showed that glutamic acid was found higher compared to other amino acids standards in both samples. Glutamic acid is non-essential amino acid which is important in umami taste substances.