Expanded packaging material for removal of carbon dioxide and kimchi odor compounds using sodium-bicarbonate-powder-impregnated activated carbon

ABSTRACT The accumulation of carbon dioxide and the release of pungent odor compounds during the storage and distribution of kimchi pose significant challenges to food safety, quality maintenance, and consumer acceptance. To address these issues, this study developed an expanded packaging material incorporating activated carbon impregnated with sodium bicarbonate. Characterization results showed that increasing the sodium bicarbonate content led to a decrease in the surface area and pore volume of the functional powder, while significantly enhancing its carbon dioxide removal capacity ( P < 0.05). Additionally, the functional powder exhibited excellent removal performance toward both acetic acid and sulfur compounds, with activated carbon being more effective for sulfur compound removal, and sodium bicarbonate being more effective for acetic acid removal. The expanded packaging sheets exhibited increased void fractions with higher blowing agent contents, which resulted in enhanced removal efficiencies for carbon dioxide and the investigated odor compounds although the mechanical strength was found to decrease. Notably, the developed packaging demonstrated effective removal efficiencies in the presence of actual kimchi, with removal capacities of >67.5 % for carbon dioxide, >99.2 % for acetic acid, and 14.2–79.4 % for sulfur compounds. These findings underscore the significant potential of the developed expanded packaging material to address distribution-related challenges and advance the food packaging industry.