Sustainable multi-layer packaging structures for enhanced food safety and shelf life

Overview

This solution offers multi-layer packaging material structures engineered to improve the safety and shelf life of food products, particularly those derived from root and tuber crops such as cassava. The proposed structures—polyester film laminated with metallized polyester film and polyethylene (PET//MET.PET//PE), and opaque white polyester-polyethylene (PET//PE)—are designed to serve as effective barriers against oxygen and water transmission, both of which are primary drivers of food spoilage.

The materials are non-reactive with food contents, making them suitable for packaging a wide range of products including seasonings, flakes, pastes, oily products, gari (toasted cassava granules), high-quality flour, instant flour, ice cream, salad cream, extruded snacks, and strips. Beyond food preservation, the packaging structures are degradable and recyclable, with the potential to be converted into pellets that serve as raw materials for producing bathroom wares, rubber sandals, kettles, and other plastic products.

Technical specifications

Key features:

• Multi-layer construction: Combines polyester (PET), metallized polyester (MET.PET), and polyethylene (PE) films to create a robust barrier structure
• Low oxygen transmission rate (OTR): The metallized layer significantly reduces oxygen ingress, slowing oxidation and spoilage
• Low water transmission rate (WTR): The laminated structure minimizes moisture exchange, preserving product texture and quality
• Non-reactive materials: Safe for direct contact with dry, oily, and semi-solid food products
• Recyclable: Materials can be converted into pellets (granules) for reuse in manufacturing bathroom wares, rubber products, and other plastic goods
• Validated storage performance: PE-based packaging maintained gari quality over 12 months with moisture content ranging from 6.54–6.80% and pH from 3.76–4.05
• Versatile application range: Suitable for dry goods, oily products, flours, dairy-based products, and extruded snacks

Technology readiness level

The packaging structures have been validated through preliminary storage trials using polyethylene for gari preservation over a 12-month period, with consistent results across ten cassava varieties replicated three times. The PET//MET.PET//PE combination builds on barrier technology already employed by multinational food packaging companies, adapted and tested for local food products.

Future validation is planned over an 18-month period: 4 months for production of packaging materials and food forms, 12 months for storage evaluation and data collection, and 2 months for data analysis and reporting. This next phase will expand testing to additional cassava-derived products and other root and tuber crop products, further confirming the structures' effectiveness across diverse food categories and storage conditions.