Microbiological and parasitological contamination of hydroponic grown curly lettuce under different optimized nutrient solutions

Lettuce is the most widely consumed vegetable in the world; however, its sanitary quality is questioned during the production process. The objective of this research was to evaluate the microbiological and parasitological contamination of curly lettuce grown in a nutrient film technique (NFT) hydroponic system with different nutrient solutions. The experiment was conducted in randomized blocks with three replicates, and the treatments corresponded to four mineral solutions, and four organomineral solutions, totaling eight nutrient solutions. At harvest, samples formed by ten plants per plot were collected and analyzed for microbiological contamination (Escherichia coli, Salmonella spp., total coliforms and thermotolerant coliforms) and parasitological contamination (endoparasites). The results showed absence of contamination by E. coli and Salmonella spp. in all samples. Few lettuce samples exhibited presence of Entamoeba histolytica, eggs and larvae of Ancylostoma spp. Lettuce cultivated with mineral solutions of Furlani, and Castellane and Ara jo and organomineral solution of Furlani were free from contamination.