A time-saving method for sealing Purdue Improved Crop Storage (PICS) bags.

Area of Science:

• Agricultural Science
• Entomology
• Postharvest Technology

Background:

• Purdue Improved Crop Storage (PICS) bags are crucial for reducing postharvest grain losses on smallholder farms.
• Conventional PICS bag closure using twist-ties (TT) is time-consuming and may compromise bag integrity.
• Growing interest exists in large-scale PICS bag utilization by farmer groups and government agencies.

Purpose of the Study:

• To evaluate the time efficiency of three novel PICS bag closure methods against the conventional twist-tie (TT) method.
• To assess the impact of different closure methods on internal oxygen levels and insect suppression within PICS bags.
• To identify an optimal PICS bag sealing technique for large-scale applications.

Main Methods:

• Compared four PICS bag closure methods: conventional twist-tie (TT), inner liner rolled (IR), folded-tied (FT), and folded-separate (FS).
• Measured the time required to seal 50 kg maize-filled PICS bags under partially and fully filled conditions.
• Monitored internal oxygen levels and insect population dynamics (Sitophilus zeamais) in sealed bags.

Main Results:

• The folded-tied (FT) method significantly reduced bag sealing time by over 34% compared to the conventional TT method.
• Internal oxygen levels in PICS bags dropped below 2% within a week, effectively suppressing insect populations regardless of infestation level.
• Oxygen depletion rates were consistent across all tested closure methods, indicating comparable hermetic sealing performance.

Conclusions:

• The folded-tied (FT) method offers a substantial time-saving alternative for sealing PICS bags, particularly beneficial for large-scale operations.
• All evaluated closure methods effectively reduce oxygen levels, leading to insect population suppression.
• The FT method presents a practical and efficient solution for enhancing PICS bag usability in food security initiatives.