PDF(Pubmed)
Abstract：
Pectin and alginate are well-established biopolymers used in natural film development. Single-polymer mucilage films were developed from freeze-dried native mucilage powder of two cultivars, \'Algerian\' and \'Morado\', and the films\' mechanical properties were compared to single-polymer pectin and alginate films developed from commercially available pectin and alginate powders. The casting method prepared films forming solutions at 2.5%, 5%, and 7.5% (w/w) for each polymer. Considerable variations were observed in the films\' strength and elasticity between the various films at different polymer concentrations. Although mucilage films could be produced at 5% (w/w), both cultivars could not produce films with a tensile strength (TS) greater than 1 MPa. Mucilage films, however, displayed > 20% elongation at break (%E) values, being noticeably more elastic than the pectin and alginate films. The mechanical properties of the various films were further modified by varying the pH of the film-forming solution. The various films showed increased TS and puncture force (PF) values, although these increases were more noticeable for pectin and alginate than mucilage films. Although single-polymer mucilage films exhibit the potential to be used in developing natural packaging, pectin and alginate films possess more suitable mechanical attributes.
摘要：
果胶和藻酸盐是用于天然薄膜开发的公认的生物聚合物。单聚合物粘液膜是从两个品种的冻干天然粘液粉中开发的，\'阿尔及利亚人\'和\'Morado\',并将薄膜的机械性能与从市售果胶和藻酸盐粉末开发的单聚合物果胶和藻酸盐薄膜进行了比较。流延法制备了2.5%的成膜溶液，5%,和每种聚合物的7.5%(w/w)。在不同聚合物浓度下，各种膜之间的膜强度和弹性观察到相当大的差异。虽然粘液膜可以以5%(w/w)生产，两个品种都无法生产拉伸强度（TS）大于1MPa的薄膜。胶膜，然而,显示>20%断裂伸长率(%E)值，明显比果胶和藻酸盐膜更具弹性。通过改变成膜溶液的pH进一步改变各种膜的机械性能。各种薄膜显示增加的TS和穿刺力（PF）值，尽管果胶和藻酸盐的这些增加比粘液膜更明显。尽管单聚合物粘液膜显示出用于开发天然包装的潜力，果胶和藻酸盐薄膜具有更合适的机械属性。
