Why flavouring exists at all
Drying destroys the volatile compounds that make fresh fruit smell of fruit, and leaves sugar, acid and tannin behind. A blend made only of dried fruit tastes tart and vague rather than of anything specific. Flavouring is the industry’s answer to a real physical problem, not a shortcut invented to deceive.
What the words mean
'Natural flavouring' means the flavour compounds were derived from a natural source — not necessarily the fruit on the front of the packet, and not necessarily the same source twice. It is a legal category about origin, not about which plant. A packet may legitimately carry natural peach flavouring derived from something other than a peach.
The first check: ingredient order
Ingredients are listed by weight. If apple, hibiscus and blackberry leaf come first and the named fruit is near the end, the named fruit is a trace and the aroma is the flavouring. This takes five seconds and settles most cases.
The second check: does the smell match the taste
Flavoured blends smell far stronger than they taste, because the aroma is applied to the surface and the material underneath is apple and hibiscus. A genuinely fruited blend is the other way round: less aroma from the packet, more body in the cup.
Which fruits survive drying
A short list, and worth knowing: blackcurrant, sour cherry and sea buckthorn hold their character. Strawberry, peach and raspberry essentially do not, which is why those three are the flavours most likely to be flavouring.