Well of course. They're our reactions--created by our brainwaves--and not intrinsic properties of the objects. Otherwise people wouldn't have different subjective reactions and their reactions wouldn't change due to physical changes, such as losing one's sense of taste and smell and therefore no longer experiencing a mango the same way.
As others have said, brainwaves and brains and humans are real, so of course beauty, flavor, etc. are real to materialists. But they're the result of certain processing in the brain.
If you don't agree, what do you think they are? Are they attributed of objects? We can say, objectively, that an apple is red, if we define red as something that can be measured by light wavelengths. So an apple will remain labelled red even if viewed by a colorblind person. We could also define and then measure its sweetness, crunchiness, etc. Those are all real.
We could even define something subjective like "delicious" based on average attributes in things that humans rate as delicious, and predict on average what most people would classify as delicious. But unlike color or hardness, the word delicious implies subjectivity. If I think something is delicious, it is, to me, and there's no accounting for taste, although I could be classified as typical or an outlier.
What do you think subjective things like beauty, deliciousness, etc. are, if not subjective experiences caused by brainwaves? Are they intrinsic properties that are attached to things, like colors, and a person who can't see the beauty in something is beauty-blind, like a person who can't see the red in an apple is colorblind? But what criteria do you use to define beauty, that's not tied to subjective human experience?
Edited to add: I just saw you answered while I was typing. Sorry, I don't share your desire, so I don't have the same natural bias to believe a certain way.