A recent study conducted by veterinary and agronomic researchers from Lusófona University in Portugal has provided a new One Health perspective on food safety in ready-to-eat (RTE) produce, with a focus on the challenges related to microbiological contamination in minimally processed fruits and vegetables. The study includes potential solutions to promote a more food-safe and healthy approach to fresh-cut fruits and vegetable production.
The importance of microbial food safety for RTE products like fresh-cut salads and fruits is crucial, given that these foods do not undergo heat treatment before consumption, especially as food markets and food production chains continue to experience exponential growth. However, the researchers express that much of the previous literature on foodborne illnesses associated with RTE produce often overlook transmission links from the initial contamination source.
According to the authors, the prevention and control of the spread of foodborne pathogens should be approached holistically, considering the entire farm-to-fork continuum, from agricultural production, processing, transport, food production, and extending to final consumption, all while adopting a One Health perspective. In this context, the researchers’ aim was to compile available information on the challenges related to microbiological contamination in minimally processed fruits and vegetables, including major reported outbreaks, specific bacterial strains, and associated statistics throughout the production chain, to address the sources of contamination at each stage, along with issues related to food manipulation and disinfection.
Contamination and Disinfection of Minimally Processed Produce
Contamination of produce can occur at various stages, during pre-harvest while the plant is in the field, at harvest, and in the post-harvest phase, encompassing transport, processing, and packaging. Main sources of microbiological contamination throughout the supply chain include soil, irrigation water, insects, and human handling.
Since minimally processed produce does not undergo heat treatment that would eliminate pathogens, spores, and toxins, the sanitation and disinfection stage is particularly critical for these commodities. At present, the predominant disinfection methods involve the application of chlorine-based disinfectants; however, the researchers state that this practice can pose risks to human health by generating carcinogenic compounds, and it is also not highly effective, as the impact of such disinfectants diminish, allowing surviving bacterial populations to multiply more rapidly than those on non-disinfected products.
Other chemical methods of disinfection that are emerging and show promise include chlorine dioxide, organic acids, hydrogen peroxide, electrolyzed water, ozonated water, and calcium-based solutions. However, these solutions result in the significant reduction of native microbial populations on produce, which, by decreasing competition for space and nutrients, may potentially result in a subsequent increase in the growth of pathogenic microorganisms. Physical methods of disinfection and preservation also exist, such as onizing radiation, ultraviolet (UV) treatment, infrared treatment, modified atmosphere packaging (MAP), or combinations such as ultrasound with ε-polylysine. These methods come with their own unique practical challenges and limitations.
Possible Future Food Safety Solutions for Minimally Processed Produce
The researchers pose possible future solutions for ensuring the food safety and extending the shelf life of minimally processed produce, specifically natural disinfectants and smart packaging. As consumer preferences shift toward natural and minimally processed products with fewer chemical additives and extended shelf life, the use of synthetic antimicrobials is becoming more restricted due to potential toxicity concerns. Natural antibacterial compounds have emerged as a promising alternative, such as acetic acid, ascorbic acid, lactic acid, essential oils, cheese whey, and others.
Additionally, smart packaging, which integrates active and intelligent features to enhance food safety and quality, may use bioactive compounds such as essential oils in package coating, nanoencapsulation, and synergistic pairings with other antibacterial agents. Moreover, using materials with smart packaging properties, such as being impermeable to oxygen, light, moisture, and certain gases, contributes to minimizing spoilage by reducing microbial activity, with nanocomposite materials providing added resistance.
Overall, research on alternative disinfectants, innovative food processing models, and emerging topics like the microbiome hold significant importance and should be integrated into future food safety assessments. Ultimately, the researchers believe that the future of food safety in fresh produce hinges on holistic approaches that prioritize both health and safety, to deliver natural and wholesome food products.
Minimally Processed Produce in a One Health Context
The researchers emphasize that, in the era of globalization, food supply chains traverse multiple national borders, leading to the internationalization and amplification of health risks, and conventional approaches to food safety are rendered inadequate as food systems become more complex. Globalization has made food supply chains more complicated, which highlights the need for a comprehensive strategy to stop the spread of antibiotic resistance (AMR) and microbial pathogens in processed foods. This shared responsibility acknowledges the interdependence of the entire food chain, from farm-to-fork.
The food industry faces difficulties as a result of a complex global food system, such as lengthier supply chains that result in longer transit times and quality risks. The researchers stress that, to address rising food safety problems more comprehensively, foodborne illness outbreaks should be investigated cooperatively by the environmental, animal, and human health sectors, with a focus on One Health principles.
The One Health approach acknowledges the interconnectedness of health systems and emphasizes cross-sectoral collaboration. The lack of collaboration across the complete food production chain has hindered the identification of contamination sources and critical stages in the supply chain. Bridging farm-to-fork through a One Health approach, especially by leveraging genomics, should be pursued to address this gap by comprehensively linking animal, food, environment, and human aspects in food production chains.