The objective of these studies was to develop an analog from surimi that would resemble abalone. Preliminary studies involved the standardization of batter preparation conditions, such as pH adjustment, optimum moisture content and batter mixing time. The texture of a gelled analog prepared with different protein adjuncts egg white, gluten and bovine serum albumin) was compared with cooked abalone for hardness, elasticity, and cohesiveness by a trained sensory evaluation panel and by instrumental methods. Serial levels of sodium carbonate were used to adjust the pH of the sol from pH 6.75 to 7.73. As the pH value rose, the textural strength of kamaboko correspondingly increased. The 0.1% level of sodium carbonate was determined suitable for further use. The moisture level in kamaboko caused significant variations in hardness (P<0.001) and cohesiveness (P<0.001). At the lowest level of moisture tested, 73.24%, gel hardness was greatest (l27N/g); with a 5% increase in moisture, the gel hardness was lower (52N/g). Sol mixing time (solubilization of myofibrillar proteins) was a very important factor to significantly affect gel texture for properties of hardness (P<0.00l), elasticity (P=0.002) and cohesiveness (P<0.001). To produce a strong, elastic and cohesive gel, 30 minutes mixing was required. In serial concentrations (O to 4%), egg white, gluten, and bovine serum albumin, were evaluated for enhancement of textural parameters in order to produce an imitation abalone product. The addition of either egg white or gluten at the two percent level resulted in the greatest hardness and most cohesive gels (P<0.001). Two percent added bovine serum albumin significantly improved gel hardness and elasticity (P=0.003 and P=0.0149, respectively). A shredded gel containing one of three protein adjuncts was effective in varying the final gel texture when incorporated with a surimi-based carrier. In overall parameters, the trained sensory evaluation panel judged the analog gel containing bovine serum albumin texturized chunks (at a 70:30 ratio to carrier) closest to cooked abalone. The instrumental measurements of textural parameters were slightly less discriminating than the trained sensory panel. / Graduation date: 1989

The influence of protein adjuncts and variations in pH on the cook-cool loss, moisture content, and texture of squid gels was investigated. Break force (P [greater than or equal to] .025), deformation to break (P [greater than or equal to] .01) and cook-cool loss (P [greater than or equal to] .001) decreased as the pH of squid gels was adjusted from 6.4 to 8.3 with sodium carbonate. The moisture content of gels increased (P [greater than or equal to] .01) as the pH was elevated. Break force (P [greater than or equal to] .001) and deformation distance to break (P [greater than or equal to] .005) were inversely correlated to gel moisture content. Protein adjuncts (2%) had a significant effect on cook-cool loss, break force and moisture content (P [greater than or equal to] .001, .026, and .018, respectively) of squid gels. Egg white produced an improved water-holding capacity over soy protein isolate and sodium caseinate. The mean cook-cool loss from gels containing egg white was 5.29 + 0.66% which was significantly (P=.05) lower than that of gels containing soy protein isolate (12.41 + 0.17%), no protein adjunct (16.65 + 3.82%) and sodium caseinate (19.75 + 2.42%). Gels containing sodium caseinate had a significantly (p [greater than or equal to] .05) lower moisture content and higher cook-cool loss (P=.05) than gels containing egg white or soy protein isolate. The break force of gels containing sodium caseinate could not be measured because the gels possessed little fracturability when compressed. The break-force of gels containing soy protein isolate or egg white were equal (P=.05), but each was less (P=.05) than observed for control gels. Holding minced squid gel sols at 4°C for 4 and 24 hours before forming and heat-setting into gels, had a significant effect on the force required to break gels (P [greater than or equal to] .001) and expressible moisture (P [greater than or equal to] .006). Control squid gels and gels containing soy protein isolate that were formed after holding for 24 hours required a lower force (P=.05) to break gels than similar gels formed after holding for 4 hours. Holding time did not alter (P [greater than or equal to] .05) moisture content, cook-cool loss or deformation at break. Reduced gel strengths observed for gels held for 24 hours prior to heat-setting was related to protease activity, loss of reactive sulfhydryl functions and/or cold temperature setting. A restructured seafood product was fabricated from mantle and tentacle muscle of squid (Loligo opalescens). Whole squid yielded 37.5 + 1.4% edible mantle and 15.3 + 1.0% tentacle meat; a total yield of 52.2 + 2.4% based upon round weight. A restructured product fabricated from heat-set fibers (60%) and squid sol (40%) yielded 33.4 + 1.0% based upon round weight. A consumer preference panel found no (P [less than or equal to] .05) differences in the product containing different protein adjuncts and judged the product to be, at least, slightly desirable (score of 6.0 on a 9 point scale). Firmness was the only sensory attribute that a trained panel found to be influenced (P [greater than or equal to] .05) by the incorporation of protein adjuncts. The product containing sodium caseinate was judged to be less firm (P=.05) than products incorporating either egg white or soy protein isolate. Trained panel scores for firmness were consistent with measurements for break force. / Graduation date: 1988

Graduation date: 1979

Thesis (M.Eng.) -- Memorial University of Newfoundland. / Typescript. Bibliography : leaves 213-216. Also available online.

Anserine and carnosine are water-soluble dipeptides that have antioxidant properties and are found in the skeletal muscle of mammals and fishes. These dipeptides are removed through the washing process in surimi production. The objective of this research was to determine the concentration of anserine and carnosine in surimi wash water (SWW) at all stages of surimi processing, and undertake preliminary methods to remove and concentrate the two dipeptides and study the effect of surimi wash water extract on color. Wash water samples were collected from a local surimi plant. The samples were treated by the following methods: centrifugaion, heat-treatment at 60, 80 and 100°C and filtration using different ultrafiltration (UF) membranes. The concentrations of the protein and the two dipeptides were analyzed using Lowry and high performance liquid chromatography with a fluorescent detector, respectively. Iron content was determined in SWW samples using atomic absorption spectrometry and colorimetry. Effect of SWW extract and other antioxidants on the color of fresh-farmed salmon were studied using color parameters-hue angle, chroma and lightness. Results showed that there was a trend: content of protein and dipeptides (anserine and carnosine) in SWW (raw) was higher in the first two stages of surimi processing. In the second set of experiment, where different heat treatments were used, it was found that the proteins and dipeptides showed similar trends. Additionally, 80°C followed by 100°C treatment were effective in removal of proteins and recovery of dipeptides. Among UF treatments, 1K molecular weight cut-off membrane was the most effective in recovery of dipeptides. Iron was less than 1 ppm in all SWW samples. Color measurement of fresh farmed salmon patties revealed that treatments of SWW extract (1%) in addition to other food antioxidants such as butylated hydroxy toluene and camosine (1%), mamtained salmon color until day 5. Therefore, SWW extract at lower concentrations may have an economical and potential use as a food antioxidant. / Graduation date: 2000

Protein solubility of Pacific whiting muscle with isoelectric point at pH 5.5 was significantly affected by pH. The highest breaking force was measured from fish proteins treated at pH 11, while high deformation values were obtained at pH 2 and 11. Texture of gels made using the conventional method were quite inferior to gels made using fish proteins treated at pH 2 or 11, while color of conventional gels was significantly better than the other treatments. SDS-PAGE revealed that fish proteins were highly denatured during acid or alkali treatment. High cathepsin B-like activity was detected from acid-aided fish proteins. Strong cathepsin L-like activity was found in fish proteins treated at pH 10.5, which corresponded with the lower breaking force and deformation obtained from those samples. Disulfide bonds contributed to high texture value in fish proteins treated at pH 11. Physicochemical characteristics of sarcoplasmic proteins (SP) from rockfish and their interaction with Alaska pollock surimi (myofibrillar proteins) were investigated. Solubility of SP was significantly suppressed at acidic pH (2-4) plus high salt concentration (0.5 M NaCl). This was also supported by SDS-PAGE results (extensively degraded SP). DSC results revealed SP gave three endothermic transitions. The least amount ofproteins was lost when treated at pH 2 or 3 followed by precipitation at pH 5.5. SP did not enhance the gelation properties of myofibrillar proteins, but positively contributed to gelation with myofibrillar proteins when compared to sucrose. Myofibrillar proteins were primary components contributing to heat-induced gelation. Salt effect on acid- or alkali-treated surimi gel was investigated. Good gels were obtained without salt using acid- and alkali-treated fish proteins. Their texture properties decreased as NaCl content increased, unlike conventional surimi gels. Consequently, NaCl did not solubilize myofibrillar proteins once the fish proteins were treated by acid or alkali. Solubility was apparently not a key factor for the texture properties of acid- or alkali-treated surimi. Transglutaminase-mediated setting reaction was partially inactivated during acid or alkaline treatment. Acid-treated surimi gel gave the best color properties. / Graduation date: 2003

Thesis--PlanA (M.S.)--University of Wisconsin--Stout, 2003. / Includes bibliographical references.

The results of SDS-PAGE and densitometry indicated that a significant amount of myofibrillar proteins was lost during surimi processing. Microfiltration (MF) was utilized to recover insoluble particulate. The MF-recovered proteins showed highly functional properties in gel hardness, cohesiveness, color, and water retention ability. The soluble proteins concentrated by ultrafiltration (UF) possessed dark colors and strong odors. However, the use of UF demonstrated the possibility of recycling water in leaching systems. To reduce the loss of myofibrillar proteins during processing, the factors causing solubilization of myofibrillar proteins were investigated. Myosin and actin were highly soluble when their ionic strengths were substantially reduced. Salt concentrations of 0.25%, 0.5%, and 1.0% NaCl reduced the solubility of myosin and actin but did not remove sarcoplasmic proteins effectively. At 2.0% NaCl, severe loss of myosin, actin, α-tropomyosin, β-tropomyosin, and troponin-T was observed. At low water/meat ratio (2:1) with increased washing cycles and washing time, more sarcoplasmic proteins per unit of water were removed without a noticeable loss of myosin or actin. Myosin heavy chain (MHC) content, water retention ability, and whiteness of the washed mince were comparable to that at high water/meat ratio (4:1). Prolonged storage and elevated temperatures caused a severe proteolysis of myofibrillar proteins. The degraded proteins had higher solubility than their native myofibrillar proteins. MHC and actin degradation both showed a good correlation to protein solubility. The relationship between conformational changes and solubility of myofibrillar proteins was investigated using myosin as a model system. The results showed that adding salt or shifting pH from the isoelectric point of myosin caused an increased surface hydrophobicity and a decreased helix structure. A slightly increased sulfhydryl content was also observed. These conformational changes resulted in an increased solubility. At high salt concentration (>1.0 M), myosin regained its helix structure with a concomitant loss of solubility. The salting out effect was probably due to the dominant hydrophobic interaction among nonpolar amino acids residues. / Graduation date: 1996 / Best scan available. Original is a black and white photocopy.

Graduation date: 2000

Soluble surimi wash water (SWW) proteins could be recovered using chitosan (Chi) complexed with alginate (Chi-Alg) generating co-products for feed formulations. Chi with a degree of deacetylation (DD) of 84% complexed with Alg at a mixing ratio (MR) of 0.2 was used to study Chi-Alg concentration and treatment time protein recovery effects. Insoluble SWW solids were removed by centrifugation and the supernatant was then adjusted to pH 6. Flocculation at 20��C using Chi-Alg at 20, 40, 100 and 150 mg/L SWW was aided by 5 mm agitation and holding for 30 mm, 1h and 24h. Concentration had an effect between low (20 and 40 mg/L) and high (100 and 150 mg/L) levels. Time had an effect between 30 min and 1h but not between 1 and 24 h. Turbidity reduction was affected only by concentration. 100 mg Chi-Alg/L SWW for 1 h achieved 83% protein adsorption and 97% turbidity reduction while lower concentrations yielding higher adsorption required longer times. Fourier Transform Infrared (FTIR) analysis of untreated and Chi-Alg treated SWW solids confirmed protein adsorption. Amide band areas normalized against a common 3005-2880 cm����� region confirmed the high protein recovery by 100 mg Chi-Alg/L SWW. Six Chi samples differing in molecular weight (MW) and degree of deacetylation (DD) were tested to recover soluble SWW solids using 20, 40, and 100 mg Chi-Alg/L SWW (0.2 MR, 1h). High (94%, 93%) and low (75%) DD chitosan had lower protein adsorption (73-75%) when compared to the intermediate (84%) DD chitosan (74-83%). Intermediate DD and high MW Chi seemed to perform better; however, SY-1000 with 94% DD did not follow this trend (79-86% protein adsorption, 85-92% turbidity reduction). Insoluble SWW (P1) and soluble solids (P2) recovered using 150 mg Chi- Alg/L SWW contained 61.4 and 73.1% protein, respectively. Rat diets formulated with 10% protein substitution by P1 and 10% and 15% by P2 had acceptability and protein efficiency ratios (PER) as high as the casein control with no deleterious effects. Rat diets with 100% P2 protein substitution showed higher PER and net protein ratio than the casein control with no deleterious effects. Protein recovered from SWW using Chi-Alg has the potential to be used in commercial feed formulations. / Graduation date: 2004