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91.
92.
Summary Phase separation of alkaline gelatin in water-acid solutions in the presence of low etherified pectin (ED 38%) were investigated.
The effects of the pectin weight fraction in pectin/gelatin mixture (qo) as well as two conditions of complex formation, namely, mixing of the binary biopolymer-solvent systems at pH 3.5 (‘mixing
conditions’), or preparation of the ternary gelatin-pectin-water systems at pH 7.5 and their subsequent acidification up to
pH 3.5 (‘titration conditions’), on phase equilibrium and macrostructure of the concentrated complex phase were established
using phase analysis, and optical microscopy. At qo<0.5 the aggregative phase separation was observed in both conditions of complex formation leading to the almost complete
concentration of both biopolymers in the bottom phase at qo=0.3 (‘mixing conditions’) and at qo=0.5 (‘titration conditions’). At qo>0.5 unusual three phase separation took place in the ‘mixing conditions’, leading to formation of supernatant (phase 1),
complex coacervate (phase 2) and concentrated pectin solution (phase 3). Possible mechanism of such phenomenon was discussed
in term of segregative and aggregative phase separations. 相似文献
93.
The effect of clay content, homogenization RPM, and pH on the mechanical and barrier properties of fish gelatin/nanoclay composite films was investigated. The addition of 5% nanoclay (w/w) increased the tensile strength from 30.31 ± 2.37 MPa to 40.71 ± 3.30 MPa. The 9 g clay/100 g gelatin film exhibited the largest improvements in oxygen and water barrier properties. Oxygen permeability decreased from 402.8 × 10−6 ± 0.7 × 10−6 g m/m2 day atm to 114.4 × 10−6 ± 16.2 × 10−6 g m/m2 day atm and the water vapor permeability decreased from 31.2 × 10−3 ± 1.6 × 10−3 ng m/m2 s Pa to 8.1 × 10−3 ± 0.1 × 10−3 ng m/m2 s Pa. The XRD and TEM observation suggested that the ultrasonication treatment (30 min at 40% output) resulted in exfoliation of the silicates. 相似文献
94.
Jui-Yang Lai 《International journal of molecular sciences》2009,10(8):3442-3456
Biocompatible materials are of considerable interest in the development of cell/drug delivery carriers for therapeutic applications. This paper investigates the effects of the Bloom index of gelatin on its interaction with retinal pigment epithelial (RPE) cells. Following two days of culture of ARPE-19 cells with gelatin samples G75-100, G175, and G300, the in vitro biocompatibility was determined by cell proliferation and viability assays, and glutamate uptake measurements, as well as cytokine expression analyses. The mitochondrial dehydrogenase activity in the G300 groups was significantly lower than that of G75-100 and G175 groups. The Live/Dead assays also showed that the gelatin samples G300 induced mild cytotoxicity. In comparison with the treatment of gelatins with low Bloom index, the exposure to high Bloom strength gelatins markedly reduced the glutamate uptake capacity of ARPE-19 cells. One possible explanation for these observations is that the presence of gelatin samples G300 with high viscosity in the medium may affect the nutrient availability to cultured cells. The analyses of pro-inflammatory cytokine IL-6 expression at both mRNA and protein levels showed that the gelatins with low Bloom index caused less cellular inflammatory reaction and had more acceptable biocompatibility than their high Bloom strength counterparts. These findings suggest that the Bloom index gives influence on cellular responses to gelatin materials. 相似文献
95.
ABSTRACT: Edible Gelidium corneum –gelatin (GCG) blend films containing grapefruit seed extract (GFSE) or green tea extract (GTE) were manufactured, and the quality of pork loins packed with the film during storage was determined. Tensile strength (TS) and water vapor permeability (WVP) of the films containing GFSE or GTE were better than those of the control. The film's antimicrobial activity against Escherichia coli O157:H7 and Listeria monocytogenes increased with increasing antimicrobial concentration, resulting in a decrease in the populations of bacteria by 0.77 to 2.08 and 0.91 to 3.30 log CFU/g, respectively. Pork loin samples were inoculated with E. coli O157:H7 and L. monocytogenes . The samples packed with the GCG film containing GFSE (0.08%) or GTE (2.80%) had a decrease in the populations of E. coli O157:H7 and L. monocytogenes of 0.69 to 1.11 and 1.05 to 1.14 log CFU/g, respectively, compared to the control after 4 d of storage. The results showed that the quality of pork loins during storage could be improved by packaging them with the GCG film containing GFSE or GTE. 相似文献
96.
为了提高酿造食醋质量,减少食醋中沉淀物的含量,探讨了利用壳聚糖、蛋清液和明胶在消除酿造食醋二次沉淀上的清除效果,并对其使用效果和使用后的食醋口感进行了比较。结果表明:使用蛋清液和明胶消除酿造食醋二次沉淀后,其效果和食醋的口感优于使用壳聚糖。 相似文献
97.
Sara Bazrafshan Maryam Mizani Gholamreza Pazuki Shahla Shahriari 《Journal of texture studies》2024,55(1):e12808
Enteral nutrition is a type of nutritional support that provides the necessary sources of energy and protein for patients who suffer from dysphagia, chronic disease, and loss of appetite. In this study, a gelatin-maltodextrin binary biopolymer system has been incorporated into a semi-solid formula. The I-optimal combination design approach was used to create 19 formulations, and the dynamic rheological properties, dynamic laser scattering, and zeta potential responses were evaluated over 30 days of storage at 5°C. Solid viscoelastic behavior has been approved since G′ > G″ in the frequency sweep test with no cross-over point. Maltodextrin may interfere within the gelatin network, and increasing the maltodextrin to gelatin (from 0.14 to 1) may lead to a wider linear viscoelastic (LVE) strain range (2.16%), a lower storage modulus at LVE (52%), a lower yield stress (46%), and a lower glass transition temperature (34%). The presence of maltodextrin may reduce the temperature of the sol-to-solid transformation by 48% and enhance its flexibility. In contrast, increasing the gelatin-to-maltodextrin ratio following melting at 37°C led to an increase in the cumulant mean and polydispersity index, indicating a relatively unstable system. The range of zeta potential values between −4.4 and 1.7 mV confirmed a tendency toward coagulation. Microscopic images revealed instability because of irregular or compact chains formed in the gelatin matrix by using higher amounts of maltodextrin. Finally, the best formula had the best rheological stability and was suitable for tube-feeding patients, with a gelatin-to-maltodextrin ratio of 4.35:3.64% w/w on day 17.4. 相似文献
98.
氧氟沙星-壳聚糖-明胶共混膜的制备及表征 总被引:7,自引:1,他引:6
制备了壳聚糖 明胶共混膜 ,测定了壳聚糖 明胶共混膜的抗张强度 ,并以抗张强度最大的壳聚糖 明胶共混膜为载体 ,氧氟沙星为模型药物制得具有抗菌性能的氧氟沙星 -壳聚糖 -明胶共混膜。通过红外光谱 (FT -IR) ,X射线衍射 (X ray) ,扫描电子显微镜 (SEM)表征了共混膜的特性。结果表明 :明胶质量分数为 2 5 %时 ,壳聚糖 明胶共混膜的抗张强度最大 ,达 5 5MPa。壳聚糖、明胶、氧氟沙星三者在共混膜中有很好的相容性 ,并且形成了分子间氢键 相似文献
99.
100.
采用玉米凝胶淀粉的中试产品,作果冻胶凝剂,冰淇淋、发酵乳酸饮料等的增稠稳定剂。试验表明:玉米凝胶淀粉具有良好的凝胶性能,可替代明胶、羧甲基纤维素钠等作胶凝剂和增稠稳定剂。 相似文献