Effect of harvesting and post-harvest practices on the microbiological quality of dates fruits (Phoenix dactylifera L.)

Abstract

In Morocco, many dates varieties are produced and marketed, including local and imported dates, mainly Deglet Nour variety. The present study aimed to evaluate microbiological contamination on ten varieties of dates from four different production areas in Morocco, from the date market of Marrakech, and from the imported Deglet Nour variety, and to show effects of harvesting and post-harvest practices on the microbiological quality of dates. Physicochemical data presented that the pH of studied varieties varies between 5 and 6 and water activity from 0.28 to 0.62. Microbiological analysis displayed that samples from Tata region presented the highest microbial spoilage with Total Viable Counts (TVC) ranging from 4.2 log CFU.g−1 to 2.6 log CFU.g−1 and yeast/moulds reaching 2.99 log CFU.g−1. Deglet Nour dates imported from Algeria, and Tunisia were less contaminated (TVC < 1.0 log CFU.g−1, yeasts/moulds < 1.0 log CFU.g−1). Coliforms, Bacillus sp. and Staphylococcus were not found in any sample. Results revealed that some varieties produced and marketed in Morocco are affected by microbial spoilage, which can be assigned to uncontrolled dates processes of harvesting and post-harvesting practices.