Bacteria that spoil pickles can actually prove useful in others ways, scientists have discovered. These microbes could also help detoxify environmentally hazardous industrial dyes that pollute water.
Some species of Lactobacilli-food-related microorganisms-can cause red colouring when combined with tartrazine, a yellow food-colouring agent used in the manufacture of dill pickles.
The new study by Ilenys Perez-Dmaz and her colleagues from the ARS Food Science Research Unit in Raleigh, N.C., indicates that Lactobacilli can transform azo dyes into non-mutagenic substances - and could be implemented in wastewater treatment applications.
Perez-Dmaz and her colleagues isolated Lactobacilli from spoiled jars of hamburger dill pickles and used those isolates to inoculate non-spoiled jars of hamburger dill pickles. Jars that contained brines with tartrazine developed the red hue on the pickle skins; those that had turmeric or no added colouring did not.
The findings from this work have been reported in the Journal of Applied Microbiology.