Rocha Patrik de Souza, Pagno Carlos Henrique, Crizel Tainara de Moraes, Flôres Simone Hickmann, Hertz Plinho Francisco
Institute of Food Science and Technology, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.
J Food Sci. 2024 Dec;89(12):9456-9465. doi: 10.1111/1750-3841.17454. Epub 2024 Oct 25.
Olive pomace (OP) waste, produced in large quantities, contains significant amounts of cellulose and fibers, making it a valuable resource for developing reinforcing ingredients in biodegradable packaging materials. This study aimed to produce nanofibers from OP using enzymatic hydrolysis with hemicellulases and cellulases, and to incorporate these nanofibers into starch films as a reinforcing agent. Cellulose nanofibers (CNFs) were prepared by alkaline pretreatment followed by enzymatic hydrolysis (with hemicellulases and cellulases) from olive pomace and applied as reinforcement in starch films in concentrations of 0.5%-5% (w/v). The nanofibers were analyzed according to composition, structural, and thermal properties. The nanofibers' suspension presented a cloudy and white color in aqueous suspension, the X-ray diffraction (XRD) analysis showed the increase of crystallinity, and the fibers' range was no wider than 100 nm (according to Scherer equation). The composition analysis showed the decrease of carbonyl groups of hemicellulose and lignin. The starch films presented a homogenous surface. The solubility from these biodegradable films significantly reduced after the incorporation of CNF, and the nanomaterial's presence improved the degradation temperature (from 310°C to 322°C) and the mechanical resistance because the tension of rupture increased from 3.79 to 6.21 MPa. PRACTICAL APPLICATION: The utilization of waste from the olive pomace for cellulose nanofiber production holds promise, given the nanofibers' ability to readily integrate into various materials, including starches used in biodegradable film production. Within these matrices, nanofibers act as structure reinforcers and significantly reduce the solubility of films. Although biodegradable films ensure the shelf life, safety, and quality of food, their properties currently do not match those of traditional petroleum-based materials at an industrial scale, indicating a need for further enhancement.
大量产生的橄榄果渣（OP）废料含有大量纤维素和纤维，使其成为开发可生物降解包装材料增强成分的宝贵资源。本研究旨在通过用半纤维素酶和纤维素酶进行酶水解从橄榄果渣中生产纳米纤维，并将这些纳米纤维作为增强剂掺入淀粉膜中。通过碱性预处理，然后用来自橄榄果渣的半纤维素酶和纤维素酶进行酶水解制备纤维素纳米纤维（CNF），并以0.5%-5%（w/v）的浓度用作淀粉膜的增强剂。根据组成、结构和热性能对纳米纤维进行了分析。纳米纤维悬浮液在水悬浮液中呈现浑浊的白色，X射线衍射（XRD）分析表明结晶度增加，并且纤维范围不超过100纳米（根据谢乐方程）。组成分析表明半纤维素和木质素的羰基减少。淀粉膜呈现均匀的表面。掺入CNF后，这些可生物降解膜的溶解度显著降低，并且纳米材料的存在提高了降解温度（从310°C提高到322°C）和机械抗性，因为断裂张力从3.79兆帕增加到6.21兆帕。实际应用：鉴于纳米纤维能够很容易地融入各种材料，包括用于可生物降解薄膜生产的淀粉，利用橄榄果渣废料生产纤维素纳米纤维具有前景。在这些基质中，纳米纤维充当结构增强剂并显著降低薄膜的溶解度。尽管可生物降解薄膜确保了食品的保质期、安全性和质量，但它们目前在工业规模上的性能与传统石油基材料不匹配，这表明需要进一步改进。
