{"id":190,"date":"2018-07-24T11:16:18","date_gmt":"2018-07-24T11:16:18","guid":{"rendered":"http:\/\/ftp6.epgpbooks.inflibnet.ac.in\/?post_type=chapter&#038;p=190"},"modified":"2019-05-16T11:26:02","modified_gmt":"2019-05-16T11:26:02","slug":"fish-and-sea-foods","status":"publish","type":"chapter","link":"https:\/\/ebooks.inflibnet.ac.in\/ftp6\/chapter\/fish-and-sea-foods\/","title":{"rendered":"Fish and Sea foods"},"content":{"raw":"<div><span style=\"float: right;\"><a href=\"https:\/\/youtu.be\/2NEmAhX-jMc\" target=\"_blank\" rel=\"noopener\"><img src=\"http:\/\/epgpbooks.inflibnet.ac.in\/wp-content\/uploads\/2018\/11\/download.png\" alt=\"epgp books\" width=\"75px\" height=\"75px;\" \/><\/a>\r\n<\/span><\/div>\r\n<div>\r\n\r\n&nbsp;\r\n\r\n<strong>Post mortem changes in fish and sea foods<\/strong>\r\n<ul>\r\n \t<li>Postmortem biochemical processes are directly linked to final quality attributes.<\/li>\r\n \t<li>Postmortem tenderization of fish muscle.<\/li>\r\n \t<li>Loss of freshness.<\/li>\r\n \t<li>Muscle spoilage.<\/li>\r\n \t<li>Autolysis.<\/li>\r\n \t<li>Fat hydrolysis.<\/li>\r\n<\/ul>\r\n<\/div>\r\n<div>\r\n\r\n&nbsp;\r\n\r\n<strong>Proteolysis in muscle<\/strong>\r\n\r\n<\/div>\r\n<div>\r\n<ul>\r\n \t<li>Myofilament degradation.<\/li>\r\n \t<li>Degradation vary from one fish species to another.<\/li>\r\n \t<li>Degradation of titin, desmin,nebulin, dystrophin, \u03b1-actinin release, myosin proteolysis, and tropomyosin delocalisation.<\/li>\r\n \t<li>Costameres also degrades within 24 hr postmortem.<\/li>\r\n \t<li>Proteolysis of sarcoplasmic 16Da protein.<\/li>\r\n \t<li>Connective tissue collagen degradation.<\/li>\r\n<\/ul>\r\n<\/div>\r\n<div>\r\n\r\n&nbsp;\r\n\r\n<strong>Postmortem muscle structural changes<\/strong>\r\n<ul>\r\n \t<li>Very little structural change occurs in fish myofibrils during postmortem.<\/li>\r\n \t<li>Fish myofibrils are structurally stable.<\/li>\r\n \t<li>Both fish and mammals show myofiber to connective tissue (endomysium) detachments within 24h postmortem.<\/li>\r\n \t<li>Perimysium shows some weakening.<\/li>\r\n \t<li style=\"text-align: justify;\">Myocommata is also mechanically weakened during storage<\/li>\r\n<\/ul>\r\n<\/div>\r\n<div>\r\n\r\n&nbsp;\r\n\r\n<strong>Role of proteases in postmortem autolysis of fish muscle<\/strong>\r\n<ul>\r\n \t<li>Physical, chemical, biochemical and microbial processes combinely deteriorate the fish flesh.<\/li>\r\n \t<li>Proteolysis of muscle protein by enzymes.<\/li>\r\n \t<li>Fat hydrolysis.<\/li>\r\n \t<li>Bacterial contamination is minimum<\/li>\r\n<\/ul>\r\n<\/div>\r\n<div>\r\n\r\n&nbsp;\r\n\r\n<strong>Changes in fish flesh biochemistry post mortem<\/strong>\r\n<ul>\r\n \t<li>Rigor mortis<\/li>\r\n \t<li>Autolysis<\/li>\r\n \t<li>Bacterial attack<\/li>\r\n \t<li>Protein denaturation<\/li>\r\n \t<li>Decreasing flesh pH<\/li>\r\n \t<li>TVB-Total Volatile Base<\/li>\r\n<\/ul>\r\n<\/div>\r\n<div>\r\n\r\n&nbsp;\r\n\r\n<strong>Rigor mortis<\/strong>\r\n<ul>\r\n \t<li><span style=\"text-align: initial; font-size: 1em;\">On death, the circulatory system stops and the ATP levels drop.<\/span><\/li>\r\n \t<li>Resulting in rigid muscles.<\/li>\r\n \t<li>Actin and myosin, combine in the presence of calcium ions to form actomyosin.<\/li>\r\n \t<li>ATP is used to supply energy for contraction.<\/li>\r\n \t<li>After loss of ATP, permanent actomyosin complex is formed.<\/li>\r\n<\/ul>\r\n<\/div>\r\n<div>\r\n\r\n&nbsp;\r\n\r\n<strong>Autolysis<\/strong>\r\n\r\n<\/div>\r\n<div>\r\n<ul>\r\n \t<li>Autolytic reactions by enzymes occurs, decomposing various compounds.<\/li>\r\n \t<li>Tasteless and bitter one compounds -By enzymes in flesh.<\/li>\r\n \t<li>Soupy mess \u2013 By gut enzymes.<\/li>\r\n<\/ul>\r\n<\/div>\r\n<div>\r\n\r\n&nbsp;\r\n\r\n<strong>Bacterial attack<\/strong>\r\n\r\n<\/div>\r\n<div>\r\n<ul>\r\n \t<li>On autolysis, bacteria start to decompose muscle.<\/li>\r\n \t<li>Anaerobic\u00a0 bacteria- Foul type spoilage.<\/li>\r\n \t<li>Slimy texture.<\/li>\r\n<\/ul>\r\n<\/div>\r\n<div>\r\n\r\n&nbsp;\r\n\r\n<strong>Protein Denaturation<\/strong>\r\n\r\n<\/div>\r\n<div>\r\n<ul>\r\n \t<li>The destruction of its secondary, tertiary and quaternary structure.<\/li>\r\n \t<li>By slow freezing and variability of storage conditions.<\/li>\r\n \t<li>Impaired water holding ability..Dull, white and spongy.<\/li>\r\n \t<li>Fibrous and tasteless.<\/li>\r\n<\/ul>\r\n<\/div>\r\n<div>\r\n\r\n&nbsp;\r\n\r\n<strong>Decreasing flesh pH<\/strong>\r\n\r\n<\/div>\r\n<div>\r\n<ul>\r\n \t<li>A living fish has a flesh pH of 7.0.<\/li>\r\n \t<li>Decrease in pH after death- Glycolysis.<\/li>\r\n \t<li>At 6.6 \u2013soft texture.<\/li>\r\n \t<li>Below this level, firm and eventually tough.<\/li>\r\n<\/ul>\r\n<\/div>\r\n<div>\r\n\r\n&nbsp;\r\n\r\n<strong>TVB-Total Volatile Base<\/strong>\r\n\r\n<\/div>\r\n<div>\r\n<ul>\r\n \t<li>Total amount of nitrogen-containing substances which are produced during storage.<\/li>\r\n \t<li>For example TMA (Trimethylamine).<\/li>\r\n \t<li>Fishy smell.<\/li>\r\n \t<li>Odourless and tasteless.<\/li>\r\n \t<li>During frozen storage- TMA oxide converted to dimethylamine (DMA) and formaldehyde.<\/li>\r\n \t<li>Formaldehyde denatures the muscle structure.<\/li>\r\n<\/ul>\r\n<\/div>\r\n<table>\r\n<tbody>\r\n<tr>\r\n<td><strong>you can view video on Fish and Sea foods<\/strong><\/td>\r\n<td><a href=\"https:\/\/youtu.be\/2NEmAhX-jMc\" target=\"_blank\" rel=\"noopener\"><img class=\"alignnone wp-image-120\" src=\"http:\/\/epgpbooks.inflibnet.ac.in\/wp-content\/uploads\/2018\/11\/download.png\" alt=\"\" width=\"36\" height=\"36\" \/><\/a><\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n\r\n<strong>\u00a0Suggested readings<\/strong>\r\n<ul>\r\n \t<li>Obatake, A., Doi, T. and Ono, T. 1988. Post-mortem change in inosine monophosphate concentration and related enzyme activity in the dark muscle fish. Bull. Jpn. Soc. Sci. Fish. 54, 283\u2013288.<\/li>\r\n \t<li>Pedrosa-menabrito, A. and Regenstein, J.M. 1988. Shelf-life extension of fresh-fish spoilage of fish. J. Food Qual. 11, 117\u2013127.<\/li>\r\n \t<li>Saito, T., Arai, K. and Matsuyoshi, M. 1959. A new method for estimating the freshness of fish. Bull. Jpn Soc. Sci. Fish. 24, 749\u2013750.<\/li>\r\n \t<li>Tanikawa, eiichi, akiba, minoru, ishiko, hirotoshi, yoshitani, setsuko. Studies on post-mortem changes in the chemical constitution of the meat of sea cucumber (stichopus japonicus selenka): Changes in the Amounts of Lactic Acid and Glycogen in the. Meat of Stichopus japonicus during the Period of Rigor Mortis. Bulletin of the faculty of fisheries hokkaido university, 6(1): 52-56 Issue Date 1955-05.<\/li>\r\n<\/ul>","rendered":"<div><span style=\"float: right;\"><a href=\"https:\/\/youtu.be\/2NEmAhX-jMc\" target=\"_blank\" rel=\"noopener\"><img decoding=\"async\" src=\"http:\/\/epgpbooks.inflibnet.ac.in\/wp-content\/uploads\/2018\/11\/download.png\" alt=\"epgp books\" width=\"75px\" height=\"75px;\" \/><\/a><br \/>\n<\/span><\/div>\n<div>\n<p>&nbsp;<\/p>\n<p><strong>Post mortem changes in fish and sea foods<\/strong><\/p>\n<ul>\n<li>Postmortem biochemical processes are directly linked to final quality attributes.<\/li>\n<li>Postmortem tenderization of fish muscle.<\/li>\n<li>Loss of freshness.<\/li>\n<li>Muscle spoilage.<\/li>\n<li>Autolysis.<\/li>\n<li>Fat hydrolysis.<\/li>\n<\/ul>\n<\/div>\n<div>\n<p>&nbsp;<\/p>\n<p><strong>Proteolysis in muscle<\/strong><\/p>\n<\/div>\n<div>\n<ul>\n<li>Myofilament degradation.<\/li>\n<li>Degradation vary from one fish species to another.<\/li>\n<li>Degradation of titin, desmin,nebulin, dystrophin, \u03b1-actinin release, myosin proteolysis, and tropomyosin delocalisation.<\/li>\n<li>Costameres also degrades within 24 hr postmortem.<\/li>\n<li>Proteolysis of sarcoplasmic 16Da protein.<\/li>\n<li>Connective tissue collagen degradation.<\/li>\n<\/ul>\n<\/div>\n<div>\n<p>&nbsp;<\/p>\n<p><strong>Postmortem muscle structural changes<\/strong><\/p>\n<ul>\n<li>Very little structural change occurs in fish myofibrils during postmortem.<\/li>\n<li>Fish myofibrils are structurally stable.<\/li>\n<li>Both fish and mammals show myofiber to connective tissue (endomysium) detachments within 24h postmortem.<\/li>\n<li>Perimysium shows some weakening.<\/li>\n<li style=\"text-align: justify;\">Myocommata is also mechanically weakened during storage<\/li>\n<\/ul>\n<\/div>\n<div>\n<p>&nbsp;<\/p>\n<p><strong>Role of proteases in postmortem autolysis of fish muscle<\/strong><\/p>\n<ul>\n<li>Physical, chemical, biochemical and microbial processes combinely deteriorate the fish flesh.<\/li>\n<li>Proteolysis of muscle protein by enzymes.<\/li>\n<li>Fat hydrolysis.<\/li>\n<li>Bacterial contamination is minimum<\/li>\n<\/ul>\n<\/div>\n<div>\n<p>&nbsp;<\/p>\n<p><strong>Changes in fish flesh biochemistry post mortem<\/strong><\/p>\n<ul>\n<li>Rigor mortis<\/li>\n<li>Autolysis<\/li>\n<li>Bacterial attack<\/li>\n<li>Protein denaturation<\/li>\n<li>Decreasing flesh pH<\/li>\n<li>TVB-Total Volatile Base<\/li>\n<\/ul>\n<\/div>\n<div>\n<p>&nbsp;<\/p>\n<p><strong>Rigor mortis<\/strong><\/p>\n<ul>\n<li><span style=\"text-align: initial; font-size: 1em;\">On death, the circulatory system stops and the ATP levels drop.<\/span><\/li>\n<li>Resulting in rigid muscles.<\/li>\n<li>Actin and myosin, combine in the presence of calcium ions to form actomyosin.<\/li>\n<li>ATP is used to supply energy for contraction.<\/li>\n<li>After loss of ATP, permanent actomyosin complex is formed.<\/li>\n<\/ul>\n<\/div>\n<div>\n<p>&nbsp;<\/p>\n<p><strong>Autolysis<\/strong><\/p>\n<\/div>\n<div>\n<ul>\n<li>Autolytic reactions by enzymes occurs, decomposing various compounds.<\/li>\n<li>Tasteless and bitter one compounds -By enzymes in flesh.<\/li>\n<li>Soupy mess \u2013 By gut enzymes.<\/li>\n<\/ul>\n<\/div>\n<div>\n<p>&nbsp;<\/p>\n<p><strong>Bacterial attack<\/strong><\/p>\n<\/div>\n<div>\n<ul>\n<li>On autolysis, bacteria start to decompose muscle.<\/li>\n<li>Anaerobic\u00a0 bacteria- Foul type spoilage.<\/li>\n<li>Slimy texture.<\/li>\n<\/ul>\n<\/div>\n<div>\n<p>&nbsp;<\/p>\n<p><strong>Protein Denaturation<\/strong><\/p>\n<\/div>\n<div>\n<ul>\n<li>The destruction of its secondary, tertiary and quaternary structure.<\/li>\n<li>By slow freezing and variability of storage conditions.<\/li>\n<li>Impaired water holding ability..Dull, white and spongy.<\/li>\n<li>Fibrous and tasteless.<\/li>\n<\/ul>\n<\/div>\n<div>\n<p>&nbsp;<\/p>\n<p><strong>Decreasing flesh pH<\/strong><\/p>\n<\/div>\n<div>\n<ul>\n<li>A living fish has a flesh pH of 7.0.<\/li>\n<li>Decrease in pH after death- Glycolysis.<\/li>\n<li>At 6.6 \u2013soft texture.<\/li>\n<li>Below this level, firm and eventually tough.<\/li>\n<\/ul>\n<\/div>\n<div>\n<p>&nbsp;<\/p>\n<p><strong>TVB-Total Volatile Base<\/strong><\/p>\n<\/div>\n<div>\n<ul>\n<li>Total amount of nitrogen-containing substances which are produced during storage.<\/li>\n<li>For example TMA (Trimethylamine).<\/li>\n<li>Fishy smell.<\/li>\n<li>Odourless and tasteless.<\/li>\n<li>During frozen storage- TMA oxide converted to dimethylamine (DMA) and formaldehyde.<\/li>\n<li>Formaldehyde denatures the muscle structure.<\/li>\n<\/ul>\n<\/div>\n<table>\n<tbody>\n<tr>\n<td><strong>you can view video on Fish and Sea foods<\/strong><\/td>\n<td><a href=\"https:\/\/youtu.be\/2NEmAhX-jMc\" target=\"_blank\" rel=\"noopener\"><img loading=\"lazy\" decoding=\"async\" class=\"alignnone wp-image-120\" src=\"http:\/\/epgpbooks.inflibnet.ac.in\/wp-content\/uploads\/2018\/11\/download.png\" alt=\"\" width=\"36\" height=\"36\" \/><\/a><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p><strong>\u00a0Suggested readings<\/strong><\/p>\n<ul>\n<li>Obatake, A., Doi, T. and Ono, T. 1988. Post-mortem change in inosine monophosphate concentration and related enzyme activity in the dark muscle fish. Bull. Jpn. Soc. Sci. Fish. 54, 283\u2013288.<\/li>\n<li>Pedrosa-menabrito, A. and Regenstein, J.M. 1988. Shelf-life extension of fresh-fish spoilage of fish. J. Food Qual. 11, 117\u2013127.<\/li>\n<li>Saito, T., Arai, K. and Matsuyoshi, M. 1959. A new method for estimating the freshness of fish. Bull. Jpn Soc. Sci. Fish. 24, 749\u2013750.<\/li>\n<li>Tanikawa, eiichi, akiba, minoru, ishiko, hirotoshi, yoshitani, setsuko. Studies on post-mortem changes in the chemical constitution of the meat of sea cucumber (stichopus japonicus selenka): Changes in the Amounts of Lactic Acid and Glycogen in the. Meat of Stichopus japonicus during the Period of Rigor Mortis. Bulletin of the faculty of fisheries hokkaido university, 6(1): 52-56 Issue Date 1955-05.<\/li>\n<\/ul>\n","protected":false},"author":2,"menu_order":28,"template":"","meta":{"pb_show_title":"on","pb_short_title":"","pb_subtitle":"","pb_authors":["kulsum-jan"],"pb_section_license":""},"chapter-type":[],"contributor":[58],"license":[],"class_list":["post-190","chapter","type-chapter","status-publish","hentry","contributor-kulsum-jan"],"part":3,"_links":{"self":[{"href":"https:\/\/ebooks.inflibnet.ac.in\/ftp6\/wp-json\/pressbooks\/v2\/chapters\/190","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ebooks.inflibnet.ac.in\/ftp6\/wp-json\/pressbooks\/v2\/chapters"}],"about":[{"href":"https:\/\/ebooks.inflibnet.ac.in\/ftp6\/wp-json\/wp\/v2\/types\/chapter"}],"author":[{"embeddable":true,"href":"https:\/\/ebooks.inflibnet.ac.in\/ftp6\/wp-json\/wp\/v2\/users\/2"}],"version-history":[{"count":5,"href":"https:\/\/ebooks.inflibnet.ac.in\/ftp6\/wp-json\/pressbooks\/v2\/chapters\/190\/revisions"}],"predecessor-version":[{"id":306,"href":"https:\/\/ebooks.inflibnet.ac.in\/ftp6\/wp-json\/pressbooks\/v2\/chapters\/190\/revisions\/306"}],"part":[{"href":"https:\/\/ebooks.inflibnet.ac.in\/ftp6\/wp-json\/pressbooks\/v2\/parts\/3"}],"metadata":[{"href":"https:\/\/ebooks.inflibnet.ac.in\/ftp6\/wp-json\/pressbooks\/v2\/chapters\/190\/metadata\/"}],"wp:attachment":[{"href":"https:\/\/ebooks.inflibnet.ac.in\/ftp6\/wp-json\/wp\/v2\/media?parent=190"}],"wp:term":[{"taxonomy":"chapter-type","embeddable":true,"href":"https:\/\/ebooks.inflibnet.ac.in\/ftp6\/wp-json\/pressbooks\/v2\/chapter-type?post=190"},{"taxonomy":"contributor","embeddable":true,"href":"https:\/\/ebooks.inflibnet.ac.in\/ftp6\/wp-json\/wp\/v2\/contributor?post=190"},{"taxonomy":"license","embeddable":true,"href":"https:\/\/ebooks.inflibnet.ac.in\/ftp6\/wp-json\/wp\/v2\/license?post=190"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}