REWACT, a French-Thai International Associated Laboratory on the cold chain in tropical countries

Mango shipping crates
Mango shipping crates
The REWACT (REducing food WAste in the cold Chain of Tropical countries) International Associated Laboratory (LIA) was launched in 2023. Its aim is to provide a better understanding of the specific characteristics of the cold chain in tropical countries and explore solutions to guarantee fruit and vegetable quality and reduce produce losses. The LIA is carrying out interdisciplinary research by combining French expertise on the cold chain (Université Paris-Saclay and INRAE-FRISE) and Thai expertise on biodegradable packaging (KU - Kasetsart University) and bio-coating (KMITL - King Mongkut’s Institute of Technology Ladkrabang) to preserve fruit and vegetable quality.

Objective : Identify the specific characteristics of the cold chain in tropical countries

The REWACT LIA consortium, created in 2023 for a period of five years (2024-2028) integrates the skills and knowledge of the Refrigeration Process Engineering for Food Safety and the Environment Research Unit (FRISE - University of Paris-Saclay, INRAE , France), ABIES Doctoral School (University of Paris-Saclay), and Thai institutes, Kasertsart University (KU) - Faculty of Agro-Industry (Bangkok, Thailand) and King Mongkut Institute of Technology Ladkrabang (KMITL) - Faculty of Engineering and Faculty of Industrial Technology (Bangkok, Thailand).

This International Associated Laboratory broadens the scope of FRISE’s successful collaboration with Thai academic partners in place since 2015 that involves exchanging researchers, supervising theses and holding seminars. FRISE’s scientific challenges are to share their experience in cold research and understand the specific nature of the cold chain in tropical countries. The REWACT LIA helps enhance the visibility of INRAE’s research in Thailand and, in the future, in Southeast Asia.

In collaboration with KMITL, FRISE conducted a field study on the influence that air transport conditions have on fruit and vegetable quality, with a case study on mango deliveries from Thailand to France. Mangoes are a seasonal fruit (April-May). Overproduction leads to about 20% losses and a sharp drop in prices, so export is one solution. As with most tropical fruits, their optimal temperature is between 10°C and 13°C, making it vital to stay within that temperature range. In practice, the produce may be exposed to temperatures that are either too high or too low, to fluctuations in temperature and humidity during the air-logistics circuit, particularly on airport tarmac or in the holds of the aircraft. These factors can have a negative effect on produce quality. In this study, FRISE provided their expertise in temperature/hygrometry instrumentation and quality measurements upon the produce’s arrival in France and in data analysis and development of prediction models for weight and colour loss during the logistics circuit.
The outcomes of this project are digital tools that can be used by export professionals to assess produce quality on arrival in the country of destination and explore technical or logistical solutions to limit produce losses.

Following the air transport project, another study aimed to improve shipping crate design and study the influence that their positions have on temperature distribution in the air cargo container. FRISE hosted Suveena Jantapirak, a doctoral candidate from Kasertsart University (KU), so she could conduct laboratory studies on the influence that various levels of openness in mango crate design have on cooling speed at different positions in the air cargo container. In that way, the project identified the coldest and hottest positions, which may damage produce quality. In addition, a test run of the steps of an air-logistics circuit was carried out by exposing the container to variable room temperatures. We found that when the container is exposed to a temperature of 35°C for 2 hours in direct sunlight, which simulates airport tarmac, the air temperature in the container can reach 50°C due to solar radiation. During that stage, the temperature of the produce in the most exposed crates at the top of the container may increase by 10°C.

Opportunities for collaboration

Survey of household refrigerator/freezer temperatures in Thailand
FRISE conducted this type of study in France a few years ago. KMITL will carry out a survey on food preservation and home refrigerator/freezer temperatures in 200 households in Thailand. FRISE will provide expertise in designing a questionnaire on consumer practices for storing food at home, temperature/hygrometer sensors placement in refrigerators/freezers and in analysing the recorded data. Comparing the results of the two countries will provide further information for the FRISE cold chain database.

Study on biodegradable film and its impact on produce quality
FRISE will host a master’s degree student from Kasertsart University (KU) in 2024 to study the influence that biodegradable-film bag permeability and produce temperature/humidity have on produce quality. Then, the objective will be to continue this study with a jointly supervised thesis.

The French-Thai REWACT LIA is contributing to the sustainability of the cold chain and reduction of food waste in tropical countries. The initial projects on the impact that air transport has on fruit and vegetable quality have produced concrete results. The study on mango transport conditions from Thailand to France brought about development of digital tools that are useful for exporters in assessing produce quality on arrival. The LIA has formally defined and strengthened this interdisciplinary collaboration.

Onrawee Laguerre FRISE research unit

Steven Duret FRISE research unit