Location: Bioproducts Research
Project Number: 2030-41000-068-013-R
Project Type: Reimbursable Cooperative Agreement
Start Date: Oct 1, 2023
End Date: Jul 31, 2025
Objective:
To ensure access of US bulk specialty crop commodities to international markets, the goal of this team is to employ a comprehensive approach to develop home compostable PLU stickers – laboratory-based research, pilot testing and commercialization efforts coupled with robust outreach and education campaigns to facilitate adoption of practices that minimize packaging waste associated with the US exports of bulk commodities. The specific aims of this proposal are:
Aim 1. Further develop the top three bio-based home-compostable pressure sensitive adhesives identified in FY22 for fresh produce labels, specifically for grapefruit and sweet potatoes, and acceptable under French Law 2020-105 on the fight against waste, and circular economy.
Approach:
The Bioproducts Research Unit at the USDA, ARS, WRRC, Albany, CA (BRU) will focus on developing and testing formulations that adhere compostable stickers to sweet potatoes and grapefruit, as these commodities will be most directly impacted by the French law. In addition, the loss of sweet potato and grapefruit exports to Europe will cause the most economic harm based on reports from USDA FAS and international retailers such as Walmart and Carrefour. Many plant-based adhesives include oils, fatty acids, proteins, starches, rosins, natural latex and rubber. For use on PLU stickers, the adhesive must be food-grade which must adhere to safety and labeling requirements listed in the Fair Package and Labeling Act administered by the US FDA and must also be generally recognized as safe (GRAS). The goal of this project is to increase the bonding strength of one or more of the aforementioned natural adhesives such that the sticker will not fall off due to exposure to a range of temperatures and humidities that are expected to be encountered during produce export, display and other handling. To test adhesive strength, the protocol described by Doll and Erhan (2011) will be followed. The adhesive will be allowed to dry for a predetermined period of time and the strength of the bond will be evaluated using a Instron tensile testing instrument. To test longevity of the sticker on the produce, adhesive will be applied to a sticker and applied to whole sweet potato and grapefruit. These samples will then be subjected to simulated environmental conditions that mimic transport by ship, display and handling. To test compostability, the adhesive will be tested in a soil compost. The test samples will undergo compostability testing in a Respirometer which can be set to replicate home composting conditions.
