九灶是白酒行业的主要固体副产品,其中含有大量未充分利用的纤维素和蛋白质。近年来,纤维素纳米纤维与蛋白质混合制备可生物降解的生物基膜材料受到了广泛的关注。在这项研究中,我们提出了一种新的方法,从九灶的强烈风味类型中同时提取卡菲林和纤维素,并通过TEMPO(2,2,6,6-四甲基哌啶-1-氧化物)氧化-压力均质化技术对纤维素进行改性以制备纤维素纳米纤维,最后将卡菲林与纤维素纳米纤维混合,制备出一种新型可生物降解的生物基复合膜。在单向和响应面实验分析的基础上,纤维素的最高纯度为82.04%。在纤维素氧化过程中,当NaClO以25mmol/g加入时,纤维素纳米纤维的粒径为80-120nm,结晶度为65.8°。最后,将卡菲林和纤维素纳米纤维混合以制备薄膜。结果表明,当纤维素纳米纤维的添加量为1%时,薄膜表面光滑,透光率为60.8%,抗拉强度最大为9.17MPa,比纯蛋白质膜高104%。接触角为34.3°。本文为制备可生物降解生物基复合薄膜材料提供了新的思路和理论依据,提高了九灶的附加值。
Jiuzao is the main solid by-products of Baijiu industry, which contain a high amount of underutilized cellulose and proteins. In recent years, cellulose nanofibers mixed with proteins to prepare biodegradable bio-based film materials have received widespread attention. In this study, we propose a novel method to simultaneously extract kafirin and cellulose from strong-flavor type of Jiuzao, and modify cellulose to prepare cellulose nanofibers by the TEMPO (2,2,6,6-tetramethylpiperidine-1-oxide) oxidation-pressure homogenization technique, and finally mix kafirin with cellulose nanofibers to prepare a new biodegradable bio-based composite film. Based on the analysis of one-way and response surface experiments, the highest purity of cellulose was 82.04 %. During cellulose oxidation, when NaClO was added at 25 mmol/g, cellulose nanofibers have a particle size of 80-120 nm, a crystallinity of 65.8°. Finally, kafirin and cellulose nanofibers were mixed to prepare films. The results showed that when cellulose nanofibers were added at 1 %, the film surface was smooth, the light transmittance was 60.8 %, and the tensile strength was 9.17 MPa at maximum, which was 104 % higher than pure protein film. The contact angle was 34.3°. This paper provides new ideas and theoretical basis for preparing biodegradable bio-based composite film materials, and improves the added value of Jiuzao.