Maria Evangelina Vallejos

The environmental impacts of fossil-based plastic food packaging and the use of grease-resistant coatings containing per- and polyfluoroalkyl substances (PFAS) are driving the development of bio-based and fluorine-free alternatives. Nanocellulose and natural waxes are promising components for PFAS-free barrier coatings, but their performance depends strongly on how they are produced, formulated, deposited, and dried. Nanocellulose provides excellent oxygen-barrier performance, particularly under dry conditions, whereas natural waxes contribute primarily to moisture and grease resistance. Their combination can therefore provide complementary barrier functions, while also introducing challenges related to dispersion, interfacial compatibility, crystallization, and coating uniformity. This review critically examines the replacement of PFAS-based coatings on food paper packaging with formulations derived from nanocellulose and natural wax. The material selection and processing strategies are addressed in relation to component structure, formulation, and performance. Key contributions, compared to previous studies, include an explanation of how the combination of nanocellulose, natural waxes, and complementary barrier materials meets the diverse functional requirements of food packaging. Likewise, the study examines how formulation parameters and processing conditions can determine interfacial compatibility, coating morphology, and barrier performance. Particular attention is given to natural wax processing, including dispersion and emulsion formation, and to formulation parameters that control interfacial interactions, coating structure, surface morphology, and barrier performance. Coating and deposition methods, drying and film formation, and the effects of processing conditions on oxygen, moisture, and grease resistance are evaluated. The review also addresses mechanical performance, sustainability and end-of-life considerations, process scale-up, economic aspects, and compatibility with industrial coating technologies. Overall, nanocellulose–wax hybrid systems offer a promising processing platform for application-specific PFAS-free barrier coatings, although further optimization and validation under realistic food-packaging conditions are required for industrial implementation.

The study explores γ-valerolactone (GVL) pulps as a sustainable approach to producing microfibrillated (MFC) and nanofibrillated (NFC) cellulose from sugarcane bagasse, a widely available agro-industrial by-product. Pulp was obtained by acid-catalyzed organosolv delignification with a GVL–water system. MFC was generated through a simple disc refiner, while NFC was produced by TEMPO-mediated oxidation followed by mechanical treatment in a colloidal mill. NFC and MFC produced using the same methodology from a commercial sugarcane totally chlorine-free (TCF) soda–anthraquinone (soda–AQ) pulp served as a reference. Structural and physicochemical characterization involved optical transmittance, turbidity, conductimetry, X-ray diffraction, viscosity, FTIR, carboxyl content, cationic demand, degree of polymerization, and morphology by scanning electron microscopy (SEM). Results demonstrated that xylan and residual lignin contents influenced MFC formation, and the NFC showed properties comparable to those of the commercial pulp with fewer fibrillation passes. The study highlights GVL pulping as a greener, efficient alternative to conventional processes, opening new pathways for producing viscosity-controlled nanocellulose suspensions suitable for advanced applications.

Three-dimensional (3D) printing based on polymers reinforced with lignocellulosic components is an accessible and sustainable technology. Cellulose-based byproducts from industry, as well as crops, food, and forestry wastes, represent potential resources for additive manufacturing and have been evaluated in recent years, primarily in combination with polymers such as PLA or ABS. During fused deposition modeling (FDM), several parameters must be considered during raw material conditioning, blending, extrusion, and 3D printing. It is essential to understand how these parameters influence the final properties and their impact on the final application. This review focuses on the latest studies of lignocellulosic byproducts for 3D printing filaments and how the parameters involved during filament production and 3D printing influence the properties of the final product. Recent studies concerning applications, technical issues, and environmental and regulatory aspects were also analyzed.

The current challenges of the primary food packaging market involve the lowest environmental impact. Biobased and biodegradable sources emerge as change strategies, implying a short life period and easy degradation in the natural ecosystem. Researchers have focused on materials that meet these requirements, merging high efficiency with the final properties. Polyhydroxyalkanoates (PHAs) and nanocellulose biocomposites are some of the most promising. PHAs are biodegradable bioplastics produced by bacteria with the potential to replace conventional fossil fuel plastics currently used in food packaging. However, some properties of PHAs need to be improved. Combining PHAs with nanocellulose is an emerging strategy to meet specific packaging requirements. The synergistic effect could enhance container features, for example, improved dimensional stability and mechanical properties. The combined components may also present high biodegradation under normal conditions. This study analyzes the current situation of nanocellulose reinforcement in PHA matrices for single-use packaging. It emphasizes the biodegradable feature of PHAs and the mechanical properties, challenges, and potential opportunities of nanocellulose-reinforced PHA bionanocomposites.

New biobased processes and products are emerging to replace conventional ones in the search for sustainable development. Xylitol is one of the most commercially valuable products from xylan-rich lignocellulosic biomass. Xylitol has multiple applications in the pharmaceutical, food, nutraceutical, and beverage industries. Recent research focuses on obtaining xylose from low-cost lignocellulosic materials through the biological route, optimizing xylitol conversion, improving byproduct removal, and increasing crystallization speed. The biological route can be an environmentally friendly alternative due to the possibility of lower energy demand and utilizing renewable feedstocks which are key factors to reach sustainability. Several integration strategies are being evaluated and are critical to developing a commercial platform. Process integration can considerably reduce the demand for energy and reagents. Also, the value-added products produced alongside xylitol are crucial, and these products are usually energy generation and bioethanol. Further, new value-added products show promising results and are relevant to improving the economic performance of the processes. The market trends of xylitol are expected to reach close to USD 1.5 billion in 2030. In addition, the improvement needed in the conversion steps and obtained yields, producing commercial-scale xylitol through the biological route, is a promising alternative to finding a more sustainable way to produce xylitol.

Vanillin (4-hydroxy-3-methoxybenzaldehyde) is the main component of natural vanilla and a relevant substance in the flavoring and aromatic industries. This study presents a kinetic model to explain both vanillin and vanillic acid concentrations achieved in the alkaline oxidation of pine kraft lignin. Considering that they come from the same precursors, this approach allows an understanding of vanillin production with reaction conditions that minimize the vanillic acid pathway directly from the lignin oligomers, thus maximizing vanillin production. This study involves the effects of oxygen partial pressure, temperature, and the presence or absence of a catalyst (CuSO₄ and Fe₂(SO₄)₃ mixture) on the vanillin and vanillic acid yields. An adapted reactor (M/K Systems Inc., Williamstown, MA, USA) with a recirculation and spray liquids system was used in the experiments. The experiments were performed using one liter of a solution of NaOH 2 M and 60 g of lignin. During the lignin oxidation reaction, liquid samples were analyzed at different times (from 0 to 200 min). The oxidation products were quantified by liquid chromatography (HPLC). The catalyzed experiments presented higher maximum vanillin yields than the non-catalyzed ones (39.2–39.6% on nitrobenzene oxidation) achieved at 150 °C. A kinetic model is proposed where the kinetic parameters were estimated using Monte Carlo methods, fitting satisfactorily to the experimental results. The statistical analysis of the kinetic parameters showed that all the studied variables significantly affect the vanillin yield.

Las tendencias actuales y el efecto de la globalización continúan marcando puntos de inflexión en el mercado de la celulosa y papel. Es así, que la fabricación de papeles y cartones se dirige hacia un escenario de innovaciones, principalmente en el mercado del embalaje de productos. Esta demanda creciente de materiales celulósico-papeleros con destino a embalaje conlleva a una transformación por parte de las industrias, ya sea en la búsqueda de nuevas formulaciones como en las tecnologías de sus procesos. El cambio ha sido más abrupto para las fábricas de papeles de impresión y escritura, que en muchos casos buscan evolucionar hacia procesos destinados a la fabricación de productos para embalaje.

La nanocelulosa, una innovadora clase de material derivada de la celulosa, se ha destacado como un componente fundamental en el ámbito de la nanotecnología y la investigación de materiales avanzados. Sus propiedades excepcionales, como su alta resistencia mecánica, ligereza, biodegradabilidad y superficie específica extraordinaria, la convierten en un recurso multifacético con aplicaciones prometedoras en diversas industrias.

La Moringa oleífera es conocida comercialmente por el valor nutricional de sus semillas, hojas, tallos y flores, para consumo humano y animal. Es un árbol de rápido crecimiento que se adapta a una amplia gama de suelos, generando gran interés en su cultivo. El Eucalyptus grandis es, en cambio, un recurso forestal instalado ampliamente cultivado en América del Sur. La celulosa microfibrilada (CMF) y la lignocelulosa microfibrilada (LCMF) han despertado un gran interés como biomaterial, ya que tiene una amplia gama de aplicaciones potenciales en diversas industrias. El objetivo de este estudio fue evaluar la aplicación de diferentes porcentajes de LCMF sobre pulpas marrones kraft fibra larga (BFL) y soda-antraquinona (AQ) fibra corta (BFC). La LCMF se obtuvo a partir de pulpas de soda-AQ de Moringa oleifera (MO) y Eucalyptus grandis (EG) tratadas mediante dos etapas de fibrilación mecánica.