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In this study, κ-carrageenan was used as an additive to improve the quality of Hypophthalmichthys molitrix-sea cucumbers (HM-SC) compound surimi gel. The effects of κ-carrageenan on rheological properties, gel strength, textural and moisture characteristics, as well as microstructure of the HM-SC surimi gel were investigated, alongside with Fourier transform infrared (FT-IR) spectroscopic characterization and SDS-PAGE analyses of the compound materials. Rheological tests showed that addition of κ-carrageenan increased the storage modulus of the HM-SC compound materials in a dosage-dependent way, which led to superior shape-forming and shape-keeping abilities in 3D printed products. The best gel strength of 1236.04 g mm was obtained in samples with κ-carrageenan addition at 1.5% (w/w). The microstructure of the HM-SC compound surimi gel became more compact and denser, with improved connectivity. These samples also had reduced cooking loss and improved water holding capacity, confirmed by changes in water mobility characterized through Low-field nuclear magnetic resonance (LF-NMR). Moreover, κ-carrageenan addition did not change protein configuration much, neither was it contributed to the aggregation and degradation of proteins. These results showed that the quality of the HM-SC compound material could be improved with the κ-carrageenan addition, which could make it suitable for 3D printing based novel product development.

In this study, Scomberomorus niphonius surimi was used as the food-ink for 3D printing and microbial transglutaminase (MTGase) as additive, aiming to investigate the effects of MTGase on the forming ability, physical properties and structural qualities of surimi and its 3D printed products. As per the rheological and printing results, the apparent viscosity of surimi containing 0.2% and 0.3% (w/w) MTGase facilitated the extrusion of surimi from the nozzle in time. In addition, the high storage modulus obtained with the two concentrations of enzyme was conductive to the maintenance of shape and appearance after printing of the 3D printed gels. The gel strength reached the maximum value of 2517.89 g mm at 0.3% MTGase concentration, and as the MTGase content increased from 0 to 0.4%, there was a gradual increase in hardness, cohesiveness and resilience of the printed gels. The gel structure changed from irregular distribution to a tight and uniform network that enhanced the ability to restrain residual water, as observed with Nuclear Magnetic Resonance (NMR). On the contrary, cooking loss increased from 4.16% to 13.49%. The results suggest that the use of MTGase can effectively improve the 3D printability, viscoelastic properties, mechanical properties and microstructure of surimi gels.

Three-dimensional printing (3DP) of surimi requires a structural modifier to achieve a stable construct. This work investigated the effect of addition of sweet potato starch (0–10% wt/wt) on the physical properties (rheological properties, gel strength, water-holding capacity [WHC], and microstructural characteristics) of surimi gels and the 3D printed behavior of these gels. The results showed that as the starch content increased, the viscosity of the starch–surimi mixture decreased facilitating the flow of the surimi out of the printer nozzle. The surimi gel with 8% sweet potato starch concentration showed good gel strength (2,021.70 g mm), WHC (82.39%), microstructural characteristics, and less cooking loss (1.95%). A comparison of the traditional surimi preparation method with 3DP showed that the surimi gel prepared by a 3D printed construct was softer in gel strength (1,398.65 g mm) and lower in hardness (945.17 g) although showing slightly higher cooking loss (6.76%) and lower WHC (72.66 g) than the conventional product. The results suggest that sweet potato starch can be effectively used as a structural enhancer for 3DP complex-shaped surimi.

Asymmetries in the production of final state particles from collider or fixed-target experiments with polarized beams or target could provide valuable information on the spin structure of the nucleon. Transverse and longitudinal spin asymmetry measurements are complementary approaches for probing the nucleon spin structure functions and understanding the QCD dynamics for such phenomena, due to the non-commutative nature of boosts and rotations in relativistic regime.The research presented in this thesis focuses on characterizing the Transverse Single Spin Asymmetries (TSSA) of inclusive $\pi^{0}$ and jet productions in polarized proton collisions at large Feynman-x ($x_{F}$) region. Theoretically these observables are explained by means of collinear twist-3 multi-parton correlations. In this picture the asymmetries originate from initial-state twist-3 parton distributions in the polarized proton and/or through the coupling between proton's initial-state transversity distribution and the final-state twist-3 fragmentation functions. The measurement of SSA for forward inclusive $\pi^{0}$ produced in $pp$ collisions up to high transverse momentum helps examine the validity and interplay of these initial- and final-state models. These models can be further explored by investigating the dependence of the TSSA on event topologies. This thesis presents the STAR measurement of TSSA for forward inclusive $\pi^{0}$ at $2.8 < \eta < 4.0$ in $\sqrt{s}$ = 500 GeV $pp$ collisions taken in 2011 with integrated luminosity of 22 $pb^{-1}$ as well as the dependence of $\pi^{0}$ TSSA on event topologies. In addition we show results of the analyses of Sivers and Collins asymmetries for forward jet-like events. The physics implications of these measurements will also be discussed.