Zhuang Chen, Tao Furong, Cui Yuezhi
Shandong Provincial Key Laboratory of Fine Chemicals, Qilu University of Technology, Jinan, PR China.
J Sci Food Agric. 2017 Aug;97(10):3384-3395. doi: 10.1002/jsfa.8189. Epub 2017 Feb 6.
In recent years, many types of food-packaging films and composites have been prepared using gelatin because of its good film-forming ability, non-toxic nature and cost-effectiveness. However, the relatively weak thermal stability, poor mechanical properties and easily-degradable quality limit the potential application of gelatin as a practical material. Microcrystalline cellulose (MCC), which comprises one of the most abundant biomass resources, has been regarded as a safe and reliable food additive because it has the same ingredients as the cellulose in people's daily intake. Food-packaging films with the excellent properties provided by gelatin and oxidized-cellulose represent a topic of great interest.
MCC was modified by 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-mediated oxidation and chosen as the base of the macromolecule cross-linker (TMN). After modification of gelatin film by TMN, the minimum amount of free -NH in solution was 4.8 × 10 mol g ). The thermal property obviously increased (from 322.31 C to 352.63 C) and was crucial for usage in the food industry. The highest water contact value 123.09° (η = 25%) indicated a better surface hydrophobicity. The higher E (58.88%) and lower E (77.16%) demonstrated that a more flexible and shatter-proof material was obtained. Water vapor uptake studies suggested increased moisture absorption and greater swelling ability.
The film material obtained in the present study was safe, stable, eco-friendly and biorefractory and could also be decomposed completely by the environment after disposal as a result of the properties of the ingredients gelatin and cellulose. The incorporation of a cellulosic cross-linker to gelatin-based films was an ideal choice with respect to developing a packaging for the food industry. © 2016 Society of Chemical Industry.
近年来，由于明胶具有良好的成膜能力、无毒且成本效益高，已被用于制备多种类型的食品包装薄膜和复合材料。然而，其相对较弱的热稳定性、较差的机械性能和易降解的特性限制了明胶作为实用材料的潜在应用。微晶纤维素（MCC）是最丰富的生物质资源之一，由于其成分与人们日常摄入的纤维素相同，被视为一种安全可靠的食品添加剂。具有明胶和氧化纤维素优异性能的食品包装薄膜是一个备受关注的课题。
通过2,2,6,6-四甲基哌啶-1-氧基（TEMPO）介导的氧化对MCC进行改性，并将其用作大分子交联剂（TMN）的基础。用TMN对明胶膜进行改性后，溶液中游离-NH的最小量为4.8×10 mol g ）。热性能明显提高（从322.31 °C提高到352.63 °C），这对食品工业的应用至关重要。最高水接触值为123.09°（η = 25%），表明具有更好的表面疏水性。较高的拉伸强度（58.
