Department of Chemical Sciences, University of Naples "Federico II", Via Cinthia, 80126 Naples, Italy.
Institute of Food Research, Norwich Research Park, Colney, Norwich NR4 7UA, UK.
Carbohydr Polym. 2014 Jun 15;106:200-8. doi: 10.1016/j.carbpol.2014.02.015. Epub 2014 Feb 13.
The growing social and economic consequences of pollution derived from plastics are focusing attention on the need to produce novel bioprocesses for enhancing food shelf-life. As a consequence, in recent years the use of edible films for food packaging is generating a huge scientific interest. In this work we report the production of an edible hydrocolloid film made by using Citrus pectin and the protein phaseolin crosslinked by microbial transglutaminase, an enzyme able to covalently modify proteins by formation of isopeptide bonds between glutamine and lysine residues. The films were characterized and their morphology was evaluated by both atomic force microscopy and scanning electron microscopy. Mechanical properties and barrier properties to CO2, O2 and water vapor have demonstrated that these films possess technological features comparable to those possessed by commercial plastics. It is worth noting that these characteristics are maintained even following storage of the films at 4°C or -20°C, suggesting that our bioplastics can be tailored to protect food at low temperature. Moreover, gastric and duodenal digestion studies conducted under the same conditions found in the human digestion system have demonstrated that transglutaminase-containing films are regularly digested encouraging an application of the proposed materials as food coatings.
塑料污染带来的日益严重的社会和经济后果，使人们开始关注开发新型生物工艺以延长食品保质期的必要性。因此，近年来，可食用薄膜在食品包装领域的应用引起了极大的科学兴趣。在这项工作中，我们报告了一种可食用的水凝胶薄膜的生产，该薄膜由柑橘果胶和微生物转谷氨酰胺酶交联的豆球蛋白组成，该酶能够通过谷氨酰胺和赖氨酸残基之间形成异肽键，共价修饰蛋白质。对薄膜进行了特性分析，并通过原子力显微镜和扫描电子显微镜对其形貌进行了评估。机械性能和对 CO2、O2 和水蒸气的阻隔性能表明，这些薄膜具有与商业塑料相当的技术特性。值得注意的是，即使将薄膜在 4°C 或-20°C 下储存，这些特性也能保持，这表明我们的生物塑料可以根据需要进行定制，以在低温下保护食品。此外，在人类消化系统中相同条件下进行的胃和十二指肠消化研究表明，含有转谷氨酰胺酶的薄膜可以被正常消化，这鼓励将所提出的材料应用于食品涂层。
