Technical Abstract: The cucumber pickling industry has sporadically experienced spoilage outbreaks in fermented cucumber products characterized by development of red color on the surface of the cucumbers. Lactobacillus casei and Lactobacillus paracasei were isolated from two outbreaks of this spoilage which occurred about 15 years apart. Both organisms were shown to produce this spoilage when inoculated into pickled cucumbers while concomitantly degrading the azo dye tartrazine (FD&C yellow no. 5), which is used as a yellow coloring in commercial pickled cucumber products. The red color does not occur in the absence of tartrazine, nor when turmeric is used as a yellow coloring in the pickles. Addition of sodium benzoate to hamburger dill pickles prevented growth of these lactic acid bacteria and the development of the red spoilage.