Karakuzu Ikizler Burcu, Yapıcı Emine, Yücel Sevil, Ermiş Ertan
Bioengineering Department, Yildiz Technical University, Istanbul 34220, Turkey.
Food Engineering Department, İstanbul Sabahattin Zaim University, Istanbul 34303, Turkey.
ACS Omega. 2023 Mar 20;8(12):11479-11491. doi: 10.1021/acsomega.3c00358. eCollection 2023 Mar 28.
In this study, mesoporous calcium silica aerogels were produced for use as an anticaking food additive in powdered foods. A low-cost precursor (sodium silicate) was used, and calcium silica aerogels with superior properties were obtained with different pH values (pH 7.0 and pH 9.0) by modeling and optimizing the production process. The Si/Ca molar ratio, reaction time, and aging temperature were determined as independent variables, and their effects and interactions to maximize the surface area and water vapor adsorption capacity (WVAC) were evaluated by response surface methodology and analysis of variance. Responses were fitted with a quadratic regression model to find optimal production conditions. Model results showed that the maximum surface area and WVAC of the calcium silica aerogel that was produced with pH 7.0 were achieved at a Si/Ca molar ratio of 2.42, a reaction time of 5 min, and an aging temperature of 25 °C. The surface area and WVAC of calcium silica aerogel powder produced with these parameters were found to be 198 m/g and 17.56%, respectively. According to the results of surface area and elemental analysis, calcium silica aerogel powder produced at pH 7.0 (CSA7) had the best results compared to that produced at pH 9.0 (CSA9). Therefore, detailed characterization methods were examined for this aerogel. The morphological review of the particles was performed with scanning electron microscopy. Elemental analysis was performed via inductively coupled plasma atomic emission spectroscopy. True density was measured in a helium pycnometer, and tapped density was calculated by the tapped method. Porosity was calculated using an equation using these two density values. The rock salt was powdered with a grinder and used as a model food for this study, and CSA7 was added at a rate of 1% by weight. The results showed that adding CSA7 powder to the rock salt powder at a rate of 1% (w/w) improved the flow behavior from the cohesive region to the easy-flow region. Consequently, calcium silica aerogel powder with a high surface area and high WVAC might be considered as an anticaking agent to use in powdered foods.
在本研究中，制备了介孔钙硅气凝胶，用作粉末状食品中的抗结块食品添加剂。使用了低成本的前驱体（硅酸钠），通过对生产工艺进行建模和优化，在不同pH值（pH 7.0和pH 9.0）下获得了具有优异性能的钙硅气凝胶。将硅/钙摩尔比、反应时间和老化温度确定为自变量，并通过响应面法和方差分析评估它们对最大化表面积和水蒸气吸附容量（WVAC）的影响及相互作用。用二次回归模型拟合响应，以找到最佳生产条件。模型结果表明，在pH 7.0条件下制备的钙硅气凝胶，在硅/钙摩尔比为2.42、反应时间为5分钟、老化温度为25℃时，可实现最大表面积和WVAC。发现用这些参数制备的钙硅气凝胶粉末的表面积和WVAC分别为198 m/g和17.56%。根据表面积和元素分析结果，pH 7.0条件下制备的钙硅气凝胶粉末（CSA7）与pH 9.0条件下制备的（CSA9）相比，效果最佳。因此，对这种气凝胶进行了详细的表征方法研究。用扫描电子显微镜对颗粒进行形态学观察。通过电感耦合等离子体原子发射光谱法进行元素分析。在氦比重瓶中测量真密度，并通过振实法计算振实密度。使用这两个密度值通过一个方程式计算孔隙率。用研磨机将岩盐磨成粉末，用作本研究的模型食品，并以1%的重量比添加CSA7。结果表明，以1%（w/w）的比例向岩盐粉末中添加CSA7粉末，可改善其流动行为，使其从粘性区域转变为易流动区域。因此，具有高表面积和高WVAC的钙硅气凝胶粉末可被视为用于粉末状食品的抗结块剂。
