Potential of Corncob-Derived Nanosilica for Controlled Hexanal Release in Tomato Preservation: A Review

Abstract

The tomato (Solanum lycopersicum L.) is a crop that is both economically and nutritionally important, but its high perishability causes huge postharvest losses, especially in warm climates with inadequate cold-chain infrastructure. Conventional preservation techniques such as refrigeration, chemical and natural preservations, biological control, edible coatings, modified atmosphere packaging, and active packaging can delay ripening and spoilage but are limited by high energy and equipment costs, safety and regulatory issues, and uneven performance in commercial settings. Hexanal, a C6 aldehyde produced from plants through the lipoxygenase pathway, is one of the promising plant-derived volatiles that has demonstrated dual efficacy in suppressing postharvest pathogens and delaying ripening by modifying ethylene production and membrane-degrading enzymes. However, the efficacy and durability of conventional application techniques such as spray, dips, and basic vapor treatments are limited by hexanal’s high volatility and oxidation susceptibility. Nanoencapsulation is a method that makes volatile molecules more stable, easier to handle, and allows for controlled release. Mesoporous nanosilica is a good carrier because it has a large surface area, a pore size that can be changed, and is stable in heat and chemicals. Recent developments reveal that silica may be produced sustainably from agricultural wastes, including corncobs, transforming underutilized biomass into valuable nanoparticles for food and agricultural use. This review summarizes existing knowledge of tomato postharvest losses and preservation strategies, the biochemical functions and mode of application of hexanal, corncobs as a sustainable silica source, and nanoencapsulation approaches for plant volatiles. It discovers important gaps at the intersection of these fields and suggests corncob-derived mesoporous nanosilica as a sustainable method for regulated hexanal delivery in tomato supply chains. The paper presents a research roadmap for creating waste-to-value, hexanal-based nanoencapsulation systems that are suited to resource-constrained environments by combining findings from postharvest technologies, plant volatiles, agricultural waste valorization, and nanotechnology.