Because of their Islamic method of slaughtering animals. Zakkaytum is a verb derived from the root word Zakaah which means to purify. It's infinitive is Tazkiyah which means purification. The Islamic mode of slaughtering an animal requires the following conditions to be met. First: The animal should be slaughtered with sharp object knife. Second: Cut wind pipe, throat and vessels of neck. Third: Blood should be drained.