Optimization programming techniques were applied to develop the least cost formulations for Pacific whiting surimi-based seafood (PWSBS). To develop the quality constraint functions, texture and color of whiting surimi gels were determined by torsion test and colorimeter, respectively. Whiting surimi gels were produced by heating at 90��C for 15 min. with 2% NaCl, five final moisture contents (74, 76, 78, 80, 82%), and various combinations of beef plasma protein (0-2%), potato starch (0-8%), and two whey protein concentrates (0-8%). Due to the non-linear constraint functions describing texture and color, a non-linear programming search technique was required to solve the least cost model for PWSBS. Results for target quality constraints are reported in this study and show that whey protein concentrate increases the texture properties and can remain economically competitive with other ingredients which similarly influence functionality in PWSBS. Water holding capacity indicated by thermal transition was also studied as a measure of gel quality. The water evaporization process was quantified using differential scanning calorimetry (DSC) for surimi gels with added potato starch or whey protein concentrate. Pacific whiting surimi gels were produced by heating in a sealed DSC pan from 30 to 90��C at a rate of 5��C/min.; gelled samples were then re-heated from 30 to 180��C at 2��C/min. in an open pan using an equivalent water mass as a reference. The DSC thermogram showed one exothermic peak followed by one endothermic peak, the former indicating a relative energy flow from the protein gels due to the delayed water evaporation. DSC parameters derived in this study showed good correlation with the texture properties of protein gels. The addition of whey protein concentrate and the increase of heating rate increased the water holding capacity of whiting surimi gels. / Graduation date: 1996

Least cost formulations for surimi seafood were studied by linear programming (LP) and nonlinear programming (NLP). The effects of water and starches on functional properties of Alaska pollock and Pacific whiting surimi gels were investigated. Six starches (modified potato starch, potato starch, modified wheat starch, wheat starch, modified waxy corn starch, and corn starch) and their mixtures were used as ingredients. Mixture and extreme vertices design were used as experimental designs. Canonical models were applied to the optimization techniques. Blending different kinds of surimi showed linear trends for each functional property, so that LP was successfully employed to optimize surimi lots. Strong interactions were found between surimi and starch or in starch mixtures. Two optimum solutions, obtained from LP and NLP, were compared in this study. Corn starch and modified waxy corn starch greatly improved the functional properties. / Graduation date: 1997