Montes Leticia, Rosell Cristina M, Moreira Ramón
Department of Chemical Engineering, Universidade de Santiago de Compostela, Santiago de Compostela, Spain.
Institute of Agrochemistry and Food Technology (IATA-CSIC), Paterna, Spain.
Front Nutr. 2022 Mar 22;9:866789. doi: 10.3389/fnut.2022.866789. eCollection 2022.
The objective of this study is to determine the effect of the addition of hydroxypropyl methylcellulose (HPMC) (from 0.5 to 2.0% w/w, starch basis) with three different viscosities (40-60, 80-120, and 2,600-5,600 mPa⋅s) to corn starch (30% w/w, total basis) gels. Average viscosimetric molecular weights (M ) of tested HPMC were determined (from 27.2 × 10 to 82.7 × 10 g/mol). Water retention capacity of HPMC varied linearly with M . The formation and curation of gels were monitored by rheology employing consecutive steps such as heating ramp (25-90°C), time sweep (90°C), cooling ramp (90-25°C), time sweep (25°C), and frequency sweep. Additionally, creep-recovery tests were performed. HPMC above 1.5% w/w delayed the range of gelatinization temperature of starch up to 2°C. Viscoelasticity and stiffness of corn starch gels with HPMC depend on both the amount of polymer added and M of the HPMC. Finally, to achieve corn gels with mimetic viscoelastic properties to wheat gel (with constant total solids), HPMC with relatively low viscosity (low M ) is necessary to be added at certain content.
本研究的目的是确定向玉米淀粉（占总量的30% w/w）凝胶中添加三种不同粘度（40 - 60、80 - 120和2600 - 5600 mPa·s）的羟丙基甲基纤维素（HPMC，占淀粉基的0.5%至2.0% w/w）的效果。测定了受试HPMC的平均粘均分子量（M ）（范围为27.2×10 至82.7×10 g/mol）。HPMC的保水能力随M 呈线性变化。通过流变学监测凝胶的形成和固化过程，采用连续步骤，如加热升温（25 - 90°C）、时间扫描（90°C）、冷却降温（90 - 25°C）、时间扫描（25°C）和频率扫描。此外，还进行了蠕变 - 回复试验。高于1.5% w/w的HPMC使淀粉糊化温度范围延迟高达2°C。含有HPMC的玉米淀粉凝胶的粘弹性和硬度取决于添加的聚合物量以及HPMC的M 。最后，为了制备具有与小麦凝胶相似粘弹性特性（总固形物含量恒定）的玉米凝胶，需要添加一定含量的相对低粘度（低M ）的HPMC。
