Graduation date: 1979

Graduation date: 1972

Graduation date: 1980

Graduation date: 1980

Thesis--Wisconsin. / Vita. Includes bibliographical references.

Thesis (M.S.) in Marine Biology--University of Maine, 2008. / Includes vita. Includes bibliographical references (leaves 112-119).

Thesis (M. Phil.)--University of Hong Kong, 2005. / Title proper from title frame. Also available in printed format.

The collagen content and composition of collagens in different age classes of shrimp were determined. Their physical and chemical characteristics were investigated. The interrelationship of shrimp size and muscle collagen content to raw and cooked meat yield was established. Total collagen content for three lots of round shrimp with weights averaging 2.58±.39, 5.27±.55 and 7.72±.96 g was determined to be 2.36, 3.35 and 3.47 mg collagen/g total musculature N, respectively. Unformed collagen comprised 53.85, 35.52 and 0.86% of the total collagen content, respectively. Maturation, as reflected by shrimp size, was accompanied by a near linear increase in formed collagen. A molecular weight of 310,000 for shrimp collagen was determined using SDS gel electrophoresis. The accuracy of this determination was compromised by limited mobility and lack of standard reference proteins of appropriate molecular weight, but did establish a molecular weight in a range common to other collagens. Variations in the amino acid composition of formed and unformed collagen reflected the function of the tissues in the musculature from which they were derived. Formed collagen contained higher amounts of glycine, proline and hydroxylysine than unformed collagen, providing a chemical basis for its structural function in formed connective tissues. Remaining amino acids, except histidine, glutamate and arginine were contained in higher amounts in unformed collagen. Unformed collagen also contained a substantial amount of unidentified components which were suspected to be amino sugar derivatives. Only trace amounts of these components were found in formed collagen. Shrimp collagen contained unusually low levels of glycine, only trace amounts of hydroxyproline and substantial quantities of tryptophan. Glycine and hydroxyproline are important amino acids in mammalian collagens, but tryptophan is usually not present. Shrimp collagen also contained higher levels of threonine, tyrosine, hydroxylysine, valine, methionine, leucine, isoleucine and phenylalanine than most other reported collagens. These variations in amino acid composition seem to reflect a requirement for a structural protein possessing unique characteristics commensurate with the anatomical structure of the species. The yield (% dry wt.) of raw and cooked (100 sec; 101°C in steam) derived through hand peeling round shrimp, was correlated (P>.001) in a positive manner by well defined power functions. Raw meat yield (% dry wt.) declined during ice storage in a linear (P>.001) manner at a rate dependent upon shrimp size. The more rapid loss of solids from large shrimp reduced yield differences as storage was extended. Raw meat losses during ice storage ranged from 0.298 to 0.318 g raw meat dry matter/100 g round shrimp/day for 2.5 and 7.5 g shrimp respectively. Dry matter weight loss from raw meat through the washing action of melting ice, was replaced in a linear (P>.05-P>.005) manner with water to maintain yield (% wet wt.) during storage. Ice storage expanded cooked yield (% dry wt.) differences between shrimp sizes. Meat losses through cooking mediated by ice storage, ranged from 0.421 to 0.303 g cooked meat dry matter/100 g round shrimp/day for 2.5 and 7.5 g shrimp, respectively. The age class dependent content and composition of collagens in the musculature of shrimp was reflected in the recovery of raw and cooked meat. Meat from small shrimp contained higher levels of unformed collagen which possessed less dry matter and degraded more rapidly in ice storage. Proteolytic action on elevated levels of unformed collagen was not reflected in the rate of ice storage losses. But, it markedly increased heat induced solubilization of solids and enhanced moisture retention through steam precooking over larger shrimp. Maturation of shrimp associated with more formed and less unformed collagen reduced solids solubilization and moisture retention through steam precooking. / Graduation date: 1982

Chilling (2-4°C) (10 min) in a solution containing 10% condensed phosphate, 5% potassium sorbate, and 0.9% citric acid (pH 6.7) stabilized round shrimp to microbial spoilage. This treatment procedure allowed refrigerated storage of round shrimp eliminating the need for ice and the accompanying deteriorative effects of water absorption and protein solids loss mediated by melting ice. The antimicrobial action of the treatment extended the time for the initiation of exponential growth by three days and the time to reach 1x10⁶ APC/g by 4.5 days over shrimp held in ice. Condensed phosphate in the treatment under optimum pH conditions retarded drip loss from the round shrimp during storage and protected the shrimp musculature from moisture and protein solids loss through steam (101°C; 100 sec) cooking. The hand peeled yield of cooked meat from shrimp held in ice of 29.8 to 32.3% (5.36-7.87% dry wt) was improved to 36.0 to 38.7% (8.16-8.99% dry wt) by the treatment system over a 15 day storage period. Treatment of shrimp held in ice with condensed phosphate just prior to cooking improved hand peeled cooked meat yield to 34.2 to 38.0%, but meat yield dry weight decreased during storage from 8.32 to 5.90%. The yield of cooked meat from shrimp held in ice was maintained by the increased recovery of meat water absorbed by raw shrimp during storage. Meat yield from stabilized shrimp was retained more by maintenance of dry matter yield with little addition to the moisture fraction of yield. Cooked meat composition was maintained very close to that observed for very freshly caught shrimp (<1 day old). / Graduation date: 1983

by Ka-ming Leung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1991. / Includes bibliographical references. / ABSTRACT --- p.i / ACKNOWLEDGEMENTS --- p.iv / LIST OF CONTENTS --- p.v / LIST OF FIGURES --- p.vii / LIST OF ABBREVIATIONS --- p.xiii / Chapter CHAPTER I --- Introduction --- p.1 / Chapter CHAPTER II --- Literature Review / Chapter 1. --- Digestive System in Decapod Crustaceans --- p.3 / Chapter 2. --- Hepatopancreas in Decapod Crustaceans --- p.7 / Chapter 3. --- Digestive Enzymes from the Hepatopancreas --- p.11 / Chapter 4. --- Changes in the Hepatopancreas during the Digestive Cycle --- p.12 / Chapter 5. --- Effects of Starvation on Hepatopancreas --- p.14 / Chapter 6. --- Biology of Shrimp Metapenaeus ensis --- p.16 / Chapter CHAPTER III --- Hepatopancreas of Shrimp Metapenaeus ensis / Chapter 1. --- Introduction --- p.20 / Chapter 2. --- Materials and Methods --- p.20 / Chapter 3. --- Results --- p.23 / Chapter 4. --- Discussion --- p.27 / Chapter CHAPTER IV --- Post-embryonic Development of the Alimentary Canalin Shrimp Metapenaeus ensis with emphasis on the Hepatopancreas / Chapter 1. --- Introduction --- p.44 / Chapter 2. --- Materials and Methods --- p.45 / Chapter 3. --- Results --- p.47 / Chapter 4. --- Discussion --- p.54 / Chapter CHAPTER V --- Optimal pH and Temperature for the Assays of Digest ive Enzyme Activities from the Hepatopancreas of Shrimp Metapenaeus ensis / Chapter 1. --- Introduction --- p.89 / Chapter 2. --- Materials and Methods --- p.90 / Chapter 3. --- Results and Discussion --- p.93 / Chapter CHAPTER VI --- Changes in the Hepatopancreas of Shrimp Metapenaeus ensis during the Digestive Cycle / Chapter 1. --- Introduction --- p.100 / Chapter 2. --- Materials and Methods --- p.101 / Chapter 3. --- Results --- p.104 / Chapter 4. --- Discussion --- p.108 / Chapter CHAPTER VII --- Effects of Starvation on the Hepatopancreas in Shrimp Metapenaeus ensis / Chapter 1. --- Introduction --- p.126 / Chapter 2. --- Materials and Methods --- p.127 / Chapter 3. --- Results --- p.130 / Chapter 4. --- Discussion --- p.135 / Chapter CHAPTER VIII --- General Conclusion --- p.160 / REFERENCES --- p.162