Accelerating the Oxygen Scavenging of Natural Rubber with Food-Grade Catalysts Impregnated on Silica-Based Platform

Abstract

Enclosed packaging often incorporates oxygen scavengers and absorbers, which aid in eliminating the presence of oxygen within the package. Most of the commercially available scavengers are rather limited due to lower scavenging capacity and being chemically based (safety issues) and need a specific condition for their activation. In the present study, a natural rubber (NR) based oxygen scavenger is reported, catalyzed by magnesium stearate (Mg-St), a food-grade ingredient. The NR with a catalyst was impregnated on silica and subsequently packed in the form of a sachet. To the best of our knowledge, the proposed formulation exhibits the highest scavenging capacity (98.7 ± 6 cm 3 /g). The scavenging was understood through spectroscopy techniques such as FTIR and NMR, which confirmed the oxidation of the NR. Importantly, the optimized oxygen scavenger maintains consistent performance across humidity levels from 11 to 92% and temperatures of 4, 27, and 45 °C, making it a reliable solution for effective oxygen removal in diverse environments. With its high oxygen-scavenging capabilities and ecofriendly nature, the developed oxygen-scavenging sachet can be a sustainable option for any type of oxygen-sensitive products. Thus, it holds tremendous potential and has high expectations for the packaging industry. The study demonstrated the applicability on fatty food samples such as fresh cheese curd. The application prolonged fresh cheese curd's shelf life from 4 to 9 days, underscoring its efficacy in maintaining the freshness of fatty food.