Development of an oil–wax coated paper as an eco-friendly and low-cost packaging solution for retail seafood markets

Abstract

Packaging plays a crucial role in preserving the quality and safety of food products, but rising environmental concerns have intensified demand for sustainable alternatives. Many existing materials are limited by high production costs, low scalability, or inadequate biocompatibility, leaving a gap in effective biodegradable solutions for high-moisture foods, including seafood. To address this, biodegradable and hydrophobic paper-based packaging was developed by applying eco-friendly oil–wax coatings onto Kraft paper substrates using two approaches: oil-only coating and oil–wax coating. Palm oil and soybean oil were applied via spray and brush techniques in single and double layers, with wax incorporated at 25%, 50%, and 75% to create different formulations. All experiments were conducted in triplicate, with uncoated Kraft paper as the control. Coating performance was evaluated through contact angle, dynamic contact angle, tensile strength, UV stability, compostability, and antibacterial activity. Contact angle analysis indicated that oil-only coatings failed to reach the hydrophobicity threshold (contact angle >90◦), whereas oil–wax coatings exceeded this threshold. Soybean wax with soybean oil (SWAX) at 25% and palm wax with soybean oil (PWAX) at 25% achieved 92.43◦ and 93.21◦ while SWAX 75% and PWAX 75% reached 97.63◦ and 97.55◦, compared to 73.14◦ in the control. No difference (p >0.05) was observed between palm oil and soybean oil in wax–oil blends, confirming uniform hydrophobic performance. Higher wax concentrations preserved structural integrity and hydrophobicity under simulated sunlight, maintained tensile strength, and ensured biodegradability, while antibacterial evaluation confirmed the complete inhibition of microbial growth. Key challenges included uniform coating thickness and color consistency. Overall, oilwax- coated Kraft paper provides a practical, eco-friendly alternative to plastic packaging for seafood, with SWAX 75% identified as the most promising candidate for commercial application.