Yes, excessive sweetness can mask or suppress other flavors in a dish, creating a less complex and balanced taste profile. It overwhelms the palate, making it difficult to perceive subtle nuances.
When a dish contains too much sugar or other sweeteners, the sweetness receptors on our tongues become overstimulated. This intense sweetness signal dominates the brain's perception of taste, effectively drowning out the signals from other taste receptors that detect saltiness, sourness, bitterness, and umami. The other flavors are still present, but the brain struggles to register them because the sweetness is so overpowering. Think of it like turning up the volume on one instrument in an orchestra so high that you can't hear the others. The balance is lost, and the overall experience suffers. The same principle applies to other strong flavors, but sweetness is particularly effective at masking other tastes due to its intensity and the way our brains prioritize it.
When adding sweetness to a recipe, start with a small amount and taste frequently, gradually increasing the sweetness until you achieve the desired balance. Remember that sweetness can also come from unexpected sources, like certain vegetables or fruits, so consider these natural sources when adjusting the overall sweetness level.