Final answer:
A high-fat meal increases gastric emptying time the most.
Step-by-step explanation:
The kind of meal that increases gastric emptying time the most (i.e., has a slow emptying rate) is a high-fat meal.
Foods heavy in carbohydrates empty the fastest, followed by high-protein foods. However, meals with a high triglyceride content, which are found in high-fat meals, remain in the stomach the longest.
For example, when the duodenum is processing fatty chyme, food can stay in the stomach for 6 hours or longer. This is due to the fact that enzymes in the small intestine digest fats slowly.