Polymer-scientific analysis of correlation between the microscopic structure and macroscopic physical properties of foods.

食品微观结构与宏观物理性质之间相关性的高分子科学分析。

• 批准号: 09660131
• 负责人: KUMAGAI Hitoshi
• 金额: $ 1.98万
• 依托单位: The University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09660131/
• 关键词: fractal; aggregate; gel; elasticity; cluster-cluster aggregation; dielectric relaxation; sol-gel transition; クラスター・クラスター凝集; Dielectric Kelaxation; Scaling Theory; Polysaccharide; Gel; Aggregate; Fractal; Elasticity

The fractal structure of aggregates in heat-induced BSA and beta-lactoglobulin gels prepared with and without CaCl_2 was examined. From the concentration dependence of the gel elasticity determined from a uniaxial compression test of the gel, the fractal dimensions D_f of the aggregates in the gels were evaluated, using the theory of Shih et al.. It was confirmed that the gels with and without CaCl_2 showed weak-and strong-link behavior in the theory of Shih et al., respectively. The obtained values of D_f were about 2 for strong-link gels and about 2.7 for weal-link gels. In addition, as for the beta-lactoglobulin gels containing CaCl_2 (weak-link type), from the analysis of the gel image obtained with confocal scanning laser microscopy of the gels, the fractal dimensions were also evaluated, the value being close to that evaluated from the gel elasticity measurements. These results indicate that the elastic behavior of the aggregate gels is a reflection of fractal structure of the ag … More gregates in the gels.The fractal dimension D_f of aggregates in dilute BSA system with salt addition was evaluated by static light scattering (SLS). The fractal structure was observed for the system with NaCl addition. The values of D_f increased with increasing beating time and ionic strength. The values of D_f were larger than those (D_f=1.8 or 2.1) predicted by the conventional cluster-cluster aggregation model, probably due to "restructuring" of aggregates during aggregation process. On the other hand, the fractal structure was not observed for the system with CaCl_2 addition.The dielectric properties of a typical ionic food polysaccharide, kappa-carrageenan, were investigated with special relevance to the sol-gel transition of its dispersed system. The dielectric relaxation around 1 MHz due to counterions bound to the polyelectrolyte was analyzed. For the disordered (coil) state of kappa-carrageenan solutions, dependence of the dielectric increment, EPSILONepsilon and that of the relaxation time, tau, on the polymer concentration, C, were summarized as EPSILONepsilon^<oc> C^0 and tau^<oc> C^<-1>, respectively, in good agreement with the scaling relations for the semi-dilute solutions derived from the polyelectrolyte solution theories. For the ordered (helix) state of kappa-carrageenan dispersed systems, the values of the dielectric parameters, DELTAepsilon and tau, were larger than the predicted values using the scaling equations for the semi-dilute solutions. The deviation between the measured and predicted values can be understood as a result of the association of the helical conformers in gels. Less

研究了热致牛血清白蛋白和β -乳球蛋白凝胶中聚集体的分形结构。根据凝胶单轴压缩试验确定的凝胶弹性的浓度依赖性，利用Shih等人的理论，评估了凝胶中聚集体的分形维数D_f。在Shih等人的理论中证实了添加和不添加CaCl_2的凝胶分别表现为弱链和强链行为。得到的D_f在强连接凝胶中约为2，在弱连接凝胶中约为2.7。此外，对含CaCl_2（弱链接型）的β -乳球蛋白凝胶，用激光共聚焦扫描显微镜对其凝胶图像进行了分形维数分析，其分形维数与凝胶弹性测量值接近。这些结果表明，聚集体凝胶的弹性行为反映了凝胶中聚集体的分形结构。用静态光散射法（SLS）评价了加入盐的稀BSA体系中聚集体的分形维数D_f。加入NaCl后，体系呈现分形结构。D_f值随加热时间和离子强度的增加而增大。D_f值大于常规聚簇聚集模型预测的D_f值（D_f=1.8或2.1），可能是由于聚集过程中聚集体的“重组”。另一方面，加入CaCl_2的体系没有出现分形结构。研究了一种典型的离子食物多糖kappa- carragean的介电性质，并对其分散体系的溶胶-凝胶转变进行了研究。分析了聚电解质上的反离子在1 MHz附近的介电弛豫。对于无序（线圈）卡帕-卡拉胶溶液，介电增量EPSILONepsilon和弛豫时间tau对聚合物浓度C的依赖性分别为EPSILONepsilon^<oc> C^0和tau^<oc> C^<-1>，这与聚电解质溶液理论推导的半稀溶液的标度关系很好地吻合。对于有序（螺旋）状态的kappa- carragean分散体系，其介电参数DELTAepsilon和tau值均大于半稀溶液标度方程的预测值。实测值和预测值之间的偏差可以理解为凝胶中螺旋构象的关联的结果。少

项目成果

T.Hagiwara: "Fractal Analysis of the Elasticity of BSA Gels." Food Hydrocolloids. 12. 29-36 (1998)

T.Hagiwara：“BSA 凝胶弹性的分形分析”。

Tomoaki Hagiwara, Hitoshi Kumagai, and Kozo Nakamura: "Fractal Analysis of Aggregates in Heat-Indnced BSA Gels" Food Hydrocolloids. (印刷中). (1998)

Tomoaki Hagiwara、Hitoshi Kumagai 和 Kozo Nakamura：“热诱导 BSA 凝胶中聚集体的分形分析”食品亲水胶体（1998 年出版）。

T.Hagiwara: "Fractal Analysis of the Elasticity of BSA and β-lactoglobulin Gel" J.Agric.Food Chem.45(10). 3807-3812 (1997)

T.Hagiwara：“BSA 和 β-乳球蛋白凝胶的弹性分形分析”J.Agric.Food Chem.45(10) 3807-3812 (1997)。

H.Kumagai: "Effect of Salt Addition on Fractal Structure or Aggregates Formed by Heating Dilute BSA Solutions" Biosci.Biotech.Biochem.63(1). 223-225 (1999)

H.Kumagai：“加盐对加热稀释 BSA 溶液形成的分形结构或聚集体的影响”Biosci.Biotech.Biochem.63(1)。

S.Ikeda: "Analysis of Sol-Gel Transition of K-Carrageenan with Scaling Concept" J.Agric.Food Chem.46(9). 3687-3693 (1998)

S.Ikeda：“利用缩放概念分析 K-卡拉胶的溶胶-凝胶转变”J.Agric.Food Chem.46(9)。