Recovery of Amino Acid from the Protein in the Head and Viscera of Frigate Mackerel by Autolysis

Abstract

The digestive conditions were investigated to recover amino acids and peptides from the protein by autolysis from the viewpoint of the effective utilization of the wastes of frigate mackerel. Protein in the head-viscera mixture was efficiently and easily autolyzed at 15•Ž for 24 h at neutral pH. Eighty-seven percent of protein in the mixture were recovered as extractive nitrogen and the autolyt ic extract obtained was rich in free amino acids and peptides. The hot water extract obtained from the autolyzate had umami taste. These results suggested that this autolytic extract can be used as a season ing material.

KARAKTER KIMIA KECAP IKAN DARI VISCERA IKAN MANYUNG (Arius sp.) YANG DIFERMENTASI DENGAN KADAR GARAM YANG BERBEDA Chemical characteristic of fish sauce from sea cat fish (Arius sp.) viscera fermented with different salt concentration

“…Selama waktu fermentasi, hidrolisis protein dilakukan oleh proteinase indigenous pada daging ikan dan saluran pencernaan juga proteinase yang dihasilkan oleh bakteri halofilik (Gildberg dan Thongthai, 2001). Autolysis dalam protein ikan selama fermentasi dipercepat dengan penambahan viscera ikan atau enzim proteinase (tripsin dan kimotripsin) (Morioka et al, 1999) atau penurunan kadar garam menjadi kurang dari 20% (Morioka et al, 1999). Gilberg dan Thongthai (2001) melaporkan bahwa kecap ikan berbahan baku ikan Capelin yang digiling diperoleh setelah 6 bulan fermentasi dengan penambahan 5-10% usus ikan cod yang kaya enzim (tripsin dan kimotripsin).…”

Autolysis of unsalted fish protein under pressurization

“…Therefore, a reduction in the concentration of salt is desirable to extend its use and for health, as well as for shortening the production period. A large number of researchers have tried to reduce the salt concentration of fish sauce 6–12 . Some reports showed that the addition of koji (mouldy rice), 7–9 fish guts 6,10 , 12,13 or proteinases 10 accelerated the autolysis of fish proteins, and reduced the autolysis time at a salt concentration < 20% 6–13 .…”

“…In addition, maintaining lower 10,13 or higher 6,11 , 12 temperatures than room temperature during the autolysis period regulated the growth of microbes. This treatment decreased the amount of salt 11–13 or required no addition of salt to fish 6,10 . The organoleptic test of the hydrolytic extracts prepared by these modified methods evaluated that the odor like fish sauce was not too strong 6,9 and the color was light, 8 whereas the taste was sweet 12,13 and somewhat bitter 10 …”

“…[6][7][8][9][10][11][12] Some reports showed that the addition of koji (mouldy rice), [7][8][9] fish guts 6,10,12,13 or proteinases 10 accelerated the autolysis of fish proteins, and reduced the autolysis time at a salt concentration < 20%. [6][7][8][9][10][11][12][13] In addition, maintaining lower 10,13 or higher 6,11,12 temperatures than room temperature during the autolysis period regulated the growth of microbes. This treatment decreased the amount of salt [11][12][13] or required no addition of salt to fish.…”

“…This treatment decreased the amount of salt [11][12][13] or required no addition of salt to fish. 6,10 The organoleptic test of the hydrolytic extracts prepared by these modified methods evaluated that the odor like fish sauce was not too strong 6,9 and the color was light, 8 whereas the taste was sweet 12,13 and somewhat bitter. 10 Knowing the above, and in order to produce a fish sauce without adding salt, we attempted to use high pressure.…”