Effect of Packaging Materials and Storage Durations on the Phytochemical and Antioxidant Profiles of Ethiopian Ginger (Zingiber officinale) Genotypes

Ginger (Zingiber officinale) is a valuable medicinal and culinary plant renowned for its rich content of bioactive compounds, including phytochemicals and antioxidants, which help neutralize free radicals and promote overall health. The stability of these compounds in dried ginger powder depends significantly on packaging materials and storage conditions. This study evaluated the influence of two packaging types—glass jars and high-density polyethylene (HDPE)—and storage durations of 3, 6, and 9 months on the phytochemical and antioxidant profiles of four Ethiopian ginger genotypes: Boziab, Volvo, Farmers Variety, and Candidate-19. The goal was to determine the most effective packaging and storage combination for preserving the nutritional quality of ginger. Total phenolic content (TPC), total flavonoid content (TFC), ferric reducing antioxidant power (FRAP), and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity were measured. Results indicated a significant reduction in both phytochemical and antioxidant activity with increased storage time, particularly beyond 6 months. Although the differences between glass jars and HDPE packaging were generally not statistically significant (p < 0.05) during the 3- and 6-month periods, glass jars demonstrated a slightly better preservation effect. Among the genotypes, Boziab stored in glass jars for 3 months recorded the highest levels of TPC, TFC, FRAP, and DPPH activity. These findings suggest that ginger should be stored at room temperature for no longer than 6 months to retain its health-promoting compounds. Further studies are recommended to explore extended storage periods, alternative packaging technologies, and strategies to enhance the retention of bioactive constituents.