Impact of climate change and global trends on the microbial quality of leafy greens
The safety of agricultural products might be influenced by different factors such as climate change and global trends. An unequivocal consequence associated to climate change is global warming, with a prediction of an average increase in global temperature by 2100 between 1.8 and 4°C. Among other climate effects, the global warming will also be associated with extended dry periods. In fact, climate change is exacerbating water scarcity problems, which is an increasingly frequent phenomenon in the European Union. The water scarcity is likely to reduce the water availability for irrigation in dry areas, which might have an impact in the microflora of vegetable products such as fresh-cut leafy greens. Global trends, leading to the reduction of chemical fertilizers, pesticides and herbicides, have increased the use of organic amendments and fertilizers, which are not produced by chemical synthesis. However, the use of organic waste and composting processes might represent a potential source of enteric contamination of fresh produce. In the present study, we have evaluated the impact of irrigation and stabilized organic wastes on the microbial quality of leafy greens to identify potential impacts of anticipated changes in climate and global change on food safety. It was observed that a reduction of about 25 and 50% of the irrigation doses regularly applied to Romaine lettuce during cultivation reduced the microbial load, including total coliforms when compared with excess water irrigation. On the other hand, the use of stabilized organic wastes at a rate of 2:225 t ha-1 significantly increased the populations of faecal coliforms in rocket leaves. These preliminary studies show the intrinsic vulnerability of the fresh produce chain to potential emerging microbial hazards associated with climate change and production trends. Thus, the risk evaluation of newly identified threats associated with the global trade system and anticipated climate change are very important to determine risk management strategies.
Martínez-Sánchez, A., Allende, A., Luna, C., Selma, M.V., Tudela, J.A. and Gil, M.I. (2018). Impact of climate change and global trends on the microbial quality of leafy greens. Acta Hortic. 1209, 51-56
irrigation management, organic amendments, faecal coliforms, leafy vegetables, electrolyte leakage, sensory quality