Bosch advises against pre-rinsing as most dishwashers are designed to work best with unrinsed dishes. Dishwasher detergent contains enzymes that latch onto food particles for more effective cleaning. Pre-rinsing can remove these particles and hinder the performance of your dishwasher. However, you should always scrape off large food scraps before loading the dishwasher to avoid clogging the dishwasher filter and/or drain.