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Optimization of Enzymatic Methods for Recovering Seafood Flavourant
ing the international trade with the USA and Canada and with Japan which is a lucrative market. The study ends with a summary of findings conclusions and recommendations for action, strategies and programmes necessary to ensure a better future and prosperity for the beef marketing system of Chihuahua.
THE ROLE OF ENDOGENOUS ENZYMES ON CONDITIONING OF BEEF. A. Alarcon-Rojol and E. Dransfield 2, 1Facultad de Zootecnia, University of Chihuahua, Mexico; 2Institute of Food Research, Bristol Laboratory, U.K. Tenderness of beef increases during conditioning. In order to investigate the role of endogenous proteinases in tenderisation of beef during cold storage, strips of bovine semitendinosus were soaked in solutions containing enzyme inhibitors and mechanical properties and enzyme activities were measured. Addition of cysteine-, aspartate-, and calpain peptide inhibitors prevented the changes in mechanical properties producing inextensible and tough meat. All enzyme activities were significantly decreased when their corresponding inhibitor was added except for b-glucuronidase activity which was not reduced. The action of inhibitors on tenderness showed the involvement of Cathepsins Band L, Calpains and Cathepsin D in conditioning, and it can be concluded that all these enzymes play a collaborative role in degrading the myofibrillar structure resulting in a improvement of tenderness in aged meat. PROXIMATE ANALYSIS, ISOLATION AND IDENTIFICATION OF FLAVOR COMPONENTS FROM RAW AND COOKED SHRIMP WASTE. S. Mandeville, V. Yaylayan and B.K. Simpson, Dept. Food Science and Agricultural Chemistry, Macdonald Campus of McGill University, Box 187, Ste Anne de Bellevue, Quebec H9X ICO. Crustacean waste generated from the fishing industry represents approximately 70070 of the total landings. This abundant waste can pose an evnironmental hazard due to the ease of deterioration of the fish tissue in the landfill sites; disposing of the waste, however, can be achieved at considerable cost to the industry. Alternatively, the waste can be utilized by extracting useful components such as flavor active compounds, and incorporating them into desirable seafood products. In order to achieve this objective, the composition of the raw and cooked waste (proximate analysis, free amino acids, sugars, carotenoids, lipids and flavor active compounds) was determined. Sugars and amino acids were determined by HPLC, carotenoids were separated by thick layer chromatography; lipids were separated and categorized into glycerides, sterols and phospholipids by TLC; flavor active compounds were extracted by different organic solvents and separated into acidic, weakly acidic, basic and neutral fractions and their sensory properties were determined. OPTIMIZATION OF ENZYMATIC METHODS FOR RECOVERING SEAFOOD FLAVOURANT. G. Nayeri, B.K. Simpson and V. Yaylayan, Dept. Food Science and Agricultural Chemistry, Macdonald Campus of McGill University, Box 187, Ste Anne de Bellevue, Quebec H9X ICO. The crustacean Fishery is one of the valuable Food industries in Canada. Crustacean waste generated from the fishing industry represents approximately 70070 of the total landing . This abundant waste material has either to be disposed of at high cost or to be converted in to useful value added products. Crustacean wastes are a rich source of useful biochemicals/nutrients like flavours, which they could be recovered and further utilized in various food and related products. The growing interest in "natural" products as well as increasing concerns about environmental pollution have stimulated efforts aimed at production of natural flavours by extraction processes from raw material and the waste from these materials during processing. This presentation will discuss optimization studies on the enzymatic recovery of shelf-stable seafood flavourants from underutilized fish and species and fish processing waste. Can. Inst. Food Sci. Technol. J. Vol. 24, No. 5, 1991
QUALITY OF FARMED COD (GADUS MORHUA). E. Dunajski, C. Hong and F. Shahidt, Dept. Biochemistry, Memorial University of Newjoundland, St. John's NF AIB 3X9. Undersized Atlantic cod (Gadus morhua) were kept in pens at Bay Bulls, Newfoundland (Sea Forest Plantation Company) from July-December. They were fed intensively on fatty fish such as capelin, herring and mackerel or on pelleted feed. The hepatosomatic index of cod was increased with intensity and duration of feed. The fillets, however, showed gaping and developed an undesirable soft texture. Fasting of fish prior to slaughtering resulted in a decrease in muscle and liver glycogen and had a positive influence on the final quality of the processed fillets and reduced the incidences of gaping. The fillets of farmed cod were somewhat enriched in omega-3 fatty acids. FATTY ACID PROFILE AND CONTENT OF CHOLESTEROL AND NUCLEIC ACIDS IN SEAL MEAT. F. Shahidi and J. Synowieckt, Dept. Biochemistry, Memorial University of Newfoundland, St. John's, NF AIB 3X9. The content of cholesterol, nucleic acids and omega-3 fatty acids in the intramuscular lipid fraction of seal meat was investigated. The cholesterol and nucleic acid content of seal meat was enhanced by mechanical deboning. The content of long-chain omega-3 fatty acids of seal meat intramuscular lipids was about 15070. Washing with water produced a beefish-coloured product with somewhat enhanced level of cholesterol and nucleic acids and a reduced concentration of omega-3 fatty acids. Removal of sacroplasmic proteins from the minces was responsible for these "apparent" effects. CHARACTERISTICS OF WASHED MECHANICALLY DEBONED CHICKEN MEAT (MDCM). A.C. Onodenalore, J. Synewiecki* and F. Shahidi, Food Science Newfoundland, St.John's, NF AIB 3X9. Necks and backs of chickens were skinned and then deboned mechanically by a POSS deboner. The resultant MDCM had a dark beefish colour. Effect of washing with aqueous solutions on the removal of lipids and hemoprotein pigments as well as sareoplasmic proteins of MDCM was studied. A yield of about 50070 was noticed for the final products which had a low fat content and had a light chickeny colour. The resultant product retained about 20-40070 of its hemoproteins and its textural properties were noticed as desirable. AMMONIA AS AN INDICATOR OF FISH FRESHNESS DURING REFRIGERATED STORAGE OF COD, HADDOCK, AND CUSK FILLETS. R.J.LeBlanc l and E.L. LeBlanc*2, IN.I.R.A.,Agri-Food Research Labs Inc.,1406-8th St., Nisku,Ab TOG 2GO;2Dept. Foods & Nutrition, University of Alberta, Edmonton, AB T6G 2M8. Fresh fish quality assessment has been based on sensory evaluation and the time consuming chemical analysis of total volatile base-nitrogen (TVB-N) and trimethylamine-nitrogen (TMA-N). This study assessed ammonia-nitrogen (NHrN) determined enzymatically as an alternative) freshness indicator in comparison to TVB-N and TMA-NJcontent of neutralized perchloric acid extracts of freshly caught cod (Gadus morhua), haddock (Melanogrammus aeglefinus), and cusk (Brosme brosme) fillets stored for ca. 13 days under institutional refrigeration at 4°C. In all three species, NHrN increased linearly after a lag of 4-5 days. However, NHrN accounted for only a minor percentage of the TVB-N produced whereas the sum of TMA-N and NHrN accounted for most of the TVB-N. PROPRIETES FONCTIONNELLES DES OEUFS DE HARENG ET DE MORUE. L. Adambounou et N. Gagne*, Departement de Biologie et Sc. Sante, Universite du Quebec it Rimouski, 300 Allee des Ursulines, G5L 3AI. Differentes proprietes fonctionnelles telles que !a viscosite des oeufs homogeneises, la capacite emulsifiante et la stabilite des emulsions (type mayonnaise) ont ete evaluees sur des rogues
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THE ROLE OF ENDOGENOUS ENZYMES ON CONDITIONING OF BEEF. A. Alarcon-Rojol and E. Dransfield 2, 1Facultad de Zootecnia, University of Chihuahua, Mexico; 2Institute of Food Research, Bristol Laboratory, U.K. Tenderness of beef increases during conditioning. In order to investigate the role of endogenous proteinases in tenderisation of beef during cold storage, strips of bovine semitendinosus were soaked in solutions containing enzyme inhibitors and mechanical properties and enzyme activities were measured. Addition of cysteine-, aspartate-, and calpain peptide inhibitors prevented the changes in mechanical properties producing inextensible and tough meat. All enzyme activities were significantly decreased when their corresponding inhibitor was added except for b-glucuronidase activity which was not reduced. The action of inhibitors on tenderness showed the involvement of Cathepsins Band L, Calpains and Cathepsin D in conditioning, and it can be concluded that all these enzymes play a collaborative role in degrading the myofibrillar structure resulting in a improvement of tenderness in aged meat. PROXIMATE ANALYSIS, ISOLATION AND IDENTIFICATION OF FLAVOR COMPONENTS FROM RAW AND COOKED SHRIMP WASTE. S. Mandeville, V. Yaylayan and B.K. Simpson, Dept. Food Science and Agricultural Chemistry, Macdonald Campus of McGill University, Box 187, Ste Anne de Bellevue, Quebec H9X ICO. Crustacean waste generated from the fishing industry represents approximately 70070 of the total landings. This abundant waste can pose an evnironmental hazard due to the ease of deterioration of the fish tissue in the landfill sites; disposing of the waste, however, can be achieved at considerable cost to the industry. Alternatively, the waste can be utilized by extracting useful components such as flavor active compounds, and incorporating them into desirable seafood products. In order to achieve this objective, the composition of the raw and cooked waste (proximate analysis, free amino acids, sugars, carotenoids, lipids and flavor active compounds) was determined. Sugars and amino acids were determined by HPLC, carotenoids were separated by thick layer chromatography; lipids were separated and categorized into glycerides, sterols and phospholipids by TLC; flavor active compounds were extracted by different organic solvents and separated into acidic, weakly acidic, basic and neutral fractions and their sensory properties were determined. OPTIMIZATION OF ENZYMATIC METHODS FOR RECOVERING SEAFOOD FLAVOURANT. G. Nayeri, B.K. Simpson and V. Yaylayan, Dept. Food Science and Agricultural Chemistry, Macdonald Campus of McGill University, Box 187, Ste Anne de Bellevue, Quebec H9X ICO. The crustacean Fishery is one of the valuable Food industries in Canada. Crustacean waste generated from the fishing industry represents approximately 70070 of the total landing . This abundant waste material has either to be disposed of at high cost or to be converted in to useful value added products. Crustacean wastes are a rich source of useful biochemicals/nutrients like flavours, which they could be recovered and further utilized in various food and related products. The growing interest in "natural" products as well as increasing concerns about environmental pollution have stimulated efforts aimed at production of natural flavours by extraction processes from raw material and the waste from these materials during processing. This presentation will discuss optimization studies on the enzymatic recovery of shelf-stable seafood flavourants from underutilized fish and species and fish processing waste. Can. Inst. Food Sci. Technol. J. Vol. 24, No. 5, 1991
QUALITY OF FARMED COD (GADUS MORHUA). E. Dunajski, C. Hong and F. Shahidt, Dept. Biochemistry, Memorial University of Newjoundland, St. John's NF AIB 3X9. Undersized Atlantic cod (Gadus morhua) were kept in pens at Bay Bulls, Newfoundland (Sea Forest Plantation Company) from July-December. They were fed intensively on fatty fish such as capelin, herring and mackerel or on pelleted feed. The hepatosomatic index of cod was increased with intensity and duration of feed. The fillets, however, showed gaping and developed an undesirable soft texture. Fasting of fish prior to slaughtering resulted in a decrease in muscle and liver glycogen and had a positive influence on the final quality of the processed fillets and reduced the incidences of gaping. The fillets of farmed cod were somewhat enriched in omega-3 fatty acids. FATTY ACID PROFILE AND CONTENT OF CHOLESTEROL AND NUCLEIC ACIDS IN SEAL MEAT. F. Shahidi and J. Synowieckt, Dept. Biochemistry, Memorial University of Newfoundland, St. John's, NF AIB 3X9. The content of cholesterol, nucleic acids and omega-3 fatty acids in the intramuscular lipid fraction of seal meat was investigated. The cholesterol and nucleic acid content of seal meat was enhanced by mechanical deboning. The content of long-chain omega-3 fatty acids of seal meat intramuscular lipids was about 15070. Washing with water produced a beefish-coloured product with somewhat enhanced level of cholesterol and nucleic acids and a reduced concentration of omega-3 fatty acids. Removal of sacroplasmic proteins from the minces was responsible for these "apparent" effects. CHARACTERISTICS OF WASHED MECHANICALLY DEBONED CHICKEN MEAT (MDCM). A.C. Onodenalore, J. Synewiecki* and F. Shahidi, Food Science Newfoundland, St.John's, NF AIB 3X9. Necks and backs of chickens were skinned and then deboned mechanically by a POSS deboner. The resultant MDCM had a dark beefish colour. Effect of washing with aqueous solutions on the removal of lipids and hemoprotein pigments as well as sareoplasmic proteins of MDCM was studied. A yield of about 50070 was noticed for the final products which had a low fat content and had a light chickeny colour. The resultant product retained about 20-40070 of its hemoproteins and its textural properties were noticed as desirable. AMMONIA AS AN INDICATOR OF FISH FRESHNESS DURING REFRIGERATED STORAGE OF COD, HADDOCK, AND CUSK FILLETS. R.J.LeBlanc l and E.L. LeBlanc*2, IN.I.R.A.,Agri-Food Research Labs Inc.,1406-8th St., Nisku,Ab TOG 2GO;2Dept. Foods & Nutrition, University of Alberta, Edmonton, AB T6G 2M8. Fresh fish quality assessment has been based on sensory evaluation and the time consuming chemical analysis of total volatile base-nitrogen (TVB-N) and trimethylamine-nitrogen (TMA-N). This study assessed ammonia-nitrogen (NHrN) determined enzymatically as an alternative) freshness indicator in comparison to TVB-N and TMA-NJcontent of neutralized perchloric acid extracts of freshly caught cod (Gadus morhua), haddock (Melanogrammus aeglefinus), and cusk (Brosme brosme) fillets stored for ca. 13 days under institutional refrigeration at 4°C. In all three species, NHrN increased linearly after a lag of 4-5 days. However, NHrN accounted for only a minor percentage of the TVB-N produced whereas the sum of TMA-N and NHrN accounted for most of the TVB-N. PROPRIETES FONCTIONNELLES DES OEUFS DE HARENG ET DE MORUE. L. Adambounou et N. Gagne*, Departement de Biologie et Sc. Sante, Universite du Quebec it Rimouski, 300 Allee des Ursulines, G5L 3AI. Differentes proprietes fonctionnelles telles que !a viscosite des oeufs homogeneises, la capacite emulsifiante et la stabilite des emulsions (type mayonnaise) ont ete evaluees sur des rogues
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