Pesticides and gas production by baker's yeast in bread dough

Abstract

SummaryPesticide residues might delay food fermentation. The aim of this study was to determine the effect of thirty‐one commercial pesticides (fourteen fungicides; eleven herbicides; one growth regulator; five insecticides) on the fermentative activity of baker's yeast in bread dough and sugared water. Yeast gas production after 3 h at 38 °C in dough or water was slightly inhibited by 10 mg kg−1 of a herbicide containing glufosinate‐ammonium and 100 mg kg−1 of fungicides with tebuconazole or metconazole. At the highest level assayed, 1000 mg kg−1, more than one‐third of the thirty‐one pesticides assayed did not impair baker's yeast gas production. Yeast cells were not inhibited by 300 mg active ingredients kg−1 in a mix of the pesticides, a concentration unlikely to be present in dough considering existing application rates in the field. Dough protected baker's yeast from pesticide residues. In sugared water, sub‐inhibitory concentrations of pesticides stimulated yeast fermentative activity. We conclude that it is unlikely that pesticide residues would impair baker's yeast gas production during bread dough fermentation.