First grade and second grade Nampla, commercially produced Thai fish sauces, were analyzed for their chemical and microbiological composition. First grade commercially produced Nampla contained higher amounts of total nitrogen, formol nitrogen, free and total amino acids compared to second grade sauce. Most of the essential amino acids were present in both grades of sauces. Low microbial counts of halotolerant microorganisms were observed in both sauces. The use of trypsin and chymotrypsin to accelerate the rate of fish sauce fermentation produced from herring, one of the underutilized fish species in Quebec, was investigated. Results showed that supplementation with trypsin and chymotrypsin increased significantly the rate of proteolysis, the amounts of total nitrogen, formol nitrogen and free amino acids in the final fish sauces (p 0.05). (Abstract shortened by UMI).

Thesis (M.Sc.)--Memorial University of Newfoundland, 2002. / Restricted until May 2003. Bibliography: leaves 72-83.

No description available.

Pacific whiting and its by-products were good raw materials for high quality fish sauce production. Heat stable and salt activated enzymes were responsible for autolytic activity in Pacific whiting and by-products. According to temperature profiles of raw materials at various salt concentrations, two fermentation temperatures, 35°C and 50°C, were selected and compared at 25% salt under static atmospheric condition. Higher yields and faster production rate were obtained from samples incubated at 50°C. Therefore, the apparent optimum condition for fish sauce fermentation using Pacific whiting and its by-products was at 50°C with 25% salt under static atmospheric condition. All physicochemical characteristics, except color and browning color, reached the level of commercial fish sauce within 20 days. Nitrogen contents in all samples reached the level of commercial fish sauce (16.3 g-N/mL) within 112 days. Predominant microorganisms found during fermentation were Staphylococcus, Bacillus and Micrococcus. Alpha-amino acid content appeared to be identified as a good parameter to estimate total nitrogen content during fermentation (adjusted R²=0.84). Soluble solid was a good index for protein degradation in fermentation (adjusted R²=0.71). Proteolytic activity in Pacific whiting and its by-products were investigated using hemoglobin as substrate. Specific substrates and specific inhibitors were also used to classify the types of enzymes responsible for protein degradation in fish sauce fermentation. Serine proteases, cathepsin L-like enzymes and metalloproteases were active at 50°C in whole fish. However, trypsin-like enzymes, and cathepsin L-like enzymes were responsible for protein degradation in by-products at 50°C. At 35°, whole fish was degraded by serine proteases, cathepsin B-like enzymes, trypsin-like enzymes, and metalloproteases. Cysteine proteases were mainly responsible for the degradation of proteins in by-products, and serine proteases and trypsin-like enzymes had a minor role in hydrolyzing of by-products during fermentation. / Graduation date: 2000

Thesis (M.Sc. (Food and Nutrition for Development))--Mahidol University, 2008. / LICL has E-Thesis 0036 ; please contact computer services.

Biochemical properties, functional properties, and market potential of Pacific whiting (PW) fish sauce were investigated. Biochemical properties of fish sauce made from whole fish (W) and a mixture (1:1) of whole fish and surimi byproducts (WB) were compared. Market potential was evaluated through phone interviews and consumer panelists. Proteolysis was primarily affected by cathepsin B-like and L-like enzymes. Acidic pH (4-5) with low salt concentration (15-20%) provided a greater degree of hydrolysis (DH), total nitrogen, and amino nitrogen content in PW fish sauce compared to the traditional process. The greatest Angiotensin Converting Enzyme (ACE) inhibition (96.8%) was found in samples fermented with 15% salt at pH 5.0 for 30 days. Anti-oxidative activity (AT) increased when fermentation continued and depended on fermentation pH. Peptides with MW <590 Da possibly played an important role in ACE inhibition. Consumer tests disclosed no significant difference in flavor liking and overall liking among fish sauce samples (W, WB, and commercial anchovy fish sauce). / Graduation date: 2004

Three New Zealand marine species, hoki (Macruronus novaezealandiae), kahawai (Arripis trutta) and trevally (Pseudocaranx dentex) were used to develop model fermented fish sausage. The formulation comprised fish mince, carbohydrate, minced garlic and salt in a mass ratio of 1 (fish): 0.15: 0.05: 0.03, respectively. The carbohydrate source was cooked rice or glucose. (Endogenous lactic acid bacteria (LAB) failed to ferment rice). Folate was also added to the mixture as a factor. The mixtures were extruded into 50 mL plastic syringes, where the needle end of the barrel had been excised by lathe. The lubricated barrel was overfilled to 60 mL, capped with a layer of ParafilmTM and aluminium foil, sealed tightly by rubber band and incubated at 30°C. Over time the piston was progressively advanced to yield samples for microbiological, physical, and chemical analysis. Over 96 hours an increase in the LAB count was observed with a concomitant decrease in pH. After fermentation was complete, the samples contained around 8.77 log cfu LAB g-1 with the pH range from 4.38 to 5.08. The microbiological and pH behaviour of each species varied between preparations. Hardness, adhesiveness, springiness and cohesiveness of the treatments increased with fermentation, except for hoki. The treatments showed different colour characteristics with fermentation. The light reflectance (L* values) of the trevally and kahawai treatments increased, while the a* (redness) and b* (yellowness) values decreased. Hoki exhibited smaller colour changes except for yellowness, which increased markedly. Proteolysis, measured colorimetrically by soluble peptide bonds, was greatest for trevally. Lipid oxidation, measured by the thiobarbituric acid method, was least for hoki, notably the species with the lowest fat content. Biogenic amines, which are a general quality indicator of fermented products, increased during fermentation. The trevally treatment generated the highest concentration of amines, but these values were lower than those reported for fermented fish sausage in Southeast Asia. Notably there were no important difference between folate treatments and those without folate. The results point to commercial opportunities and further research with New Zealand marine species, especially trevally. To improve the product quality and to show geographical exclusivity, further research could be done by using starter culture, and a New Zealand staple carbohydrate source such as kumara and potato, and spices and herbs which are commonly used in New Zealand, such as rosemary, thyme and sage or specific to New Zealand, such as horopito. In addition, sensory studies should also be performed before the products could be tested in the market.

Three New Zealand marine species, hoki (Macruronus novaezealandiae), kahawai (Arripis trutta) and trevally (Pseudocaranx dentex) were used to develop model fermented fish sausage. The formulation comprised fish mince, carbohydrate, minced garlic and salt in a mass ratio of 1 (fish): 0.15: 0.05: 0.03, respectively. The carbohydrate source was cooked rice or glucose. (Endogenous lactic acid bacteria (LAB) failed to ferment rice). Folate was also added to the mixture as a factor. The mixtures were extruded into 50 mL plastic syringes, where the needle end of the barrel had been excised by lathe. The lubricated barrel was overfilled to 60 mL, capped with a layer of ParafilmTM and aluminium foil, sealed tightly by rubber band and incubated at 30°C. Over time the piston was progressively advanced to yield samples for microbiological, physical, and chemical analysis. Over 96 hours an increase in the LAB count was observed with a concomitant decrease in pH. After fermentation was complete, the samples contained around 8.77 log cfu LAB g-1 with the pH range from 4.38 to 5.08. The microbiological and pH behaviour of each species varied between preparations. Hardness, adhesiveness, springiness and cohesiveness of the treatments increased with fermentation, except for hoki. The treatments showed different colour characteristics with fermentation. The light reflectance (L* values) of the trevally and kahawai treatments increased, while the a* (redness) and b* (yellowness) values decreased. Hoki exhibited smaller colour changes except for yellowness, which increased markedly. Proteolysis, measured colorimetrically by soluble peptide bonds, was greatest for trevally. Lipid oxidation, measured by the thiobarbituric acid method, was least for hoki, notably the species with the lowest fat content. Biogenic amines, which are a general quality indicator of fermented products, increased during fermentation. The trevally treatment generated the highest concentration of amines, but these values were lower than those reported for fermented fish sausage in Southeast Asia. Notably there were no important difference between folate treatments and those without folate. The results point to commercial opportunities and further research with New Zealand marine species, especially trevally. To improve the product quality and to show geographical exclusivity, further research could be done by using starter culture, and a New Zealand staple carbohydrate source such as kumara and potato, and spices and herbs which are commonly used in New Zealand, such as rosemary, thyme and sage or specific to New Zealand, such as horopito. In addition, sensory studies should also be performed before the products could be tested in the market.

Thesis (M.Sc. (Microbiology))--Mahidol University, 1983.

Thesis (Ph. D.)--University of Wisconsin--Madison, 2002. / Includes bibliographical references (leaves 449-492).