The effect of lye concentration and pasteurization on the fermentation of Spanish-style Manzanilla green olives was investigated. Results showed that a rapid, normal fermentation always occurred when the proper lye was used, and only in the case of an inappropriate alkaline treatment could pasteurization help the growth of lactobacilli. Although pasteurization does not seem to affect color of processed olives, texture tests gave lower values for pasteurized samples than for those obtained from nonpasteurized olives.