To investigate the enthalpy relaxation behavior of maltitol glass system,differential scanning calorimetry(DSC) was used to obtain the specific heat capacity[C p(T)] near the glass transition temperature(T g) at...To investigate the enthalpy relaxation behavior of maltitol glass system,differential scanning calorimetry(DSC) was used to obtain the specific heat capacity[C p(T)] near the glass transition temperature(T g) at different cooling rates ranged between 1 and 20 K/min.Three phenomenological models of enthalpy relaxation,ToolNarayanaswamy-Moynihan(TNM) model,Adam-Gibbs-Vogel(AGV) model and Gómez Ribelles(GR) model,were used to simulate the experimental data.The models' parameters were obtained via a curve-fitting method.The results indicate that TNM and AGV models gave the almost identical prediction powers and can reproduce the curves of experimental C p(T) very well.However,the prediction power of GR model evolved from configurational entropy approach is not so good as those of TNM and AGV models.In particular,the metastable limit state parameter(δ) introduced by Gómez Ribelles has insignificant effect on the enthalpy relaxation of the small molecular hydrogen-bonding glass system.展开更多
Prebiotic-like effects of maltitol were investigated supplementing two groups of rats with either 5% maltodextrin (control group) or 5% maltitol (maltitol group). A third group was supplemented with 5% maltitol at fir...Prebiotic-like effects of maltitol were investigated supplementing two groups of rats with either 5% maltodextrin (control group) or 5% maltitol (maltitol group). A third group was supplemented with 5% maltitol at first and then with 5% maltodextrin (maltitol/maltodextrin group). Faecal parameters were monitored throughout the experiment and caecal parameters at the end. The weights of caecal content and caecal wall were significantly higher in the maltitol group than in the control group, but not in the maltitol/maltodextrin group. Propionic acid concentration was significantly higher in the maltitol group compared to both control and maltitol/maltodextrin group. Faecal parameters were also influenced by the dietary supplementation with maltitol: the amount of dry matter in feces decreased and alpha-glucosidase activity increased. These effects lasted 28 days in the maltitol only group, whereas they stopped some days after the switch to maltodextrin in the maltitol/maltodextrin group. Maltitol could induce prebiotic-like effects.展开更多
以蔗糖、麦芽糖醇及二者复配的三元溶液为渗透溶液,探究渗透脱水处理对黄桃果块质构特性、介电特性、细胞壁多糖含量以及微观结构的变化,并利用核磁共振氢谱(1H nuclear magnetic resonance,1H NMR)技术测定了可溶性糖含量的变化,明确...以蔗糖、麦芽糖醇及二者复配的三元溶液为渗透溶液,探究渗透脱水处理对黄桃果块质构特性、介电特性、细胞壁多糖含量以及微观结构的变化,并利用核磁共振氢谱(1H nuclear magnetic resonance,1H NMR)技术测定了可溶性糖含量的变化,明确麦芽糖醇和蔗糖的协同作用在渗透脱水过程中对黄桃果块特性的改善作用。结果表明:相较于对照组,SM14(蔗糖、麦芽糖醇质量比1∶4的溶液)显著降低黄桃果块的硬度、咀嚼性和黏附性。渗透脱水处理导致黄桃果块的阻抗和有效电阻显著降低,同时诱导静电容量显著增加,表明渗透脱水可能作用于细胞壁多糖而使果肉细胞特性改变。1H NMR检测结果发现,与蔗糖组相比,三元渗透液处理显著降低了黄桃果块组织中蔗糖的含量,其中SM14处理组蔗糖信号强度仅为19803.9±156.00,麦芽糖醇信号强度为54934.9±1239.11。此外,相比较对照组,SM14组水溶性果胶和鳌合性果胶含量均显著增加,分别为(26.63±1.80)mg/g和(21.59±0.71)mg/g,碱溶性果胶含量显著降低,为(27.24±0.46)mg/g。微观结构观察发现,SM14处理组细胞圆润且完整度较高,塌陷程度低,细胞壁厚度明显增加,这可能是由于蔗糖与麦芽糖醇之间的交互作用有对细胞的协同保护作用。因此,蔗糖与麦芽糖醇复配的三元渗透溶液可以有效地改善二元渗透脱水导致的黄桃果块品质劣变等问题,同时拓宽了糖醇的应用场景。展开更多
基金Supported by the National Natural Science Foundation of China(No.20803016)the Natural Science Foundation of Anhui Province,China(No.070414163)
文摘To investigate the enthalpy relaxation behavior of maltitol glass system,differential scanning calorimetry(DSC) was used to obtain the specific heat capacity[C p(T)] near the glass transition temperature(T g) at different cooling rates ranged between 1 and 20 K/min.Three phenomenological models of enthalpy relaxation,ToolNarayanaswamy-Moynihan(TNM) model,Adam-Gibbs-Vogel(AGV) model and Gómez Ribelles(GR) model,were used to simulate the experimental data.The models' parameters were obtained via a curve-fitting method.The results indicate that TNM and AGV models gave the almost identical prediction powers and can reproduce the curves of experimental C p(T) very well.However,the prediction power of GR model evolved from configurational entropy approach is not so good as those of TNM and AGV models.In particular,the metastable limit state parameter(δ) introduced by Gómez Ribelles has insignificant effect on the enthalpy relaxation of the small molecular hydrogen-bonding glass system.
文摘Prebiotic-like effects of maltitol were investigated supplementing two groups of rats with either 5% maltodextrin (control group) or 5% maltitol (maltitol group). A third group was supplemented with 5% maltitol at first and then with 5% maltodextrin (maltitol/maltodextrin group). Faecal parameters were monitored throughout the experiment and caecal parameters at the end. The weights of caecal content and caecal wall were significantly higher in the maltitol group than in the control group, but not in the maltitol/maltodextrin group. Propionic acid concentration was significantly higher in the maltitol group compared to both control and maltitol/maltodextrin group. Faecal parameters were also influenced by the dietary supplementation with maltitol: the amount of dry matter in feces decreased and alpha-glucosidase activity increased. These effects lasted 28 days in the maltitol only group, whereas they stopped some days after the switch to maltodextrin in the maltitol/maltodextrin group. Maltitol could induce prebiotic-like effects.