First off, let's clarify exactly what we mean by caramel. E150a is a naturally extracted caramel additive, possessing a dark brown colour, that is often utilized in sauces, canned goods, beer, whisk(e)y, biscuits and pickles.
Different batches of whiskies from barrel-aged stocks will often display variations in hue, and most customers unfortunately expect one bottle of a particular whisk(e)y to have the same appearance as the next. Therefore, within the Scottish and Irish whisk(e)y industries, E150a is used as a colour-corrective to ensure consistency of colour in the bottled product from one year to the next. It
may (and I emphasize may) also be true that
very inexpensive Scotches (which have undergone close to the minimum permitted 3 years of barrel maturation - ALL Scotch has to be aged in wood at least that long) contain E150a not only as a colouring agent, but to help smooth out the rough edges and add a slight degree of sweetness. Responsible bottlers will aim to minimize the use of E150a. Some will eschew the practice altogether.
Most spirits coming off the stills ARE relatively colourless, though the nature of local water used in the distillation process as well as the incorporation of minute quantities of copper (copper stills DO thin and wear out over time!) in the fresh spirit can alter the clarity almost imperceptibly.
It is quite common, though the demand for entirely natural (not coloured or chill-filtered) whiskies is growing and bottling houses seem to be responding bit by bit.
E150a certainly has flavour. And to suggest that its utilization doesn't affect the taste of a whisk(e)y simply isn't true, although extremely restrained use might be hard to detect.
Ex-Bourbon barrels have been the mainstay of the Scotch industry for at least the last ˝-Century. This is primarily an issue of economics - and who ever accused the Scots of not being frugal?
Nonetheless, at other times in history, ex-Sherry and Madeira casks have seen their heydays for the very same reason - plentiful, cheap supplies. Scotch distillers will usually recycle these barrels/casks 2 or 3 times. Each time such a barrel/cask is reused, less of the flavour characteristic of the original contents held within the pores of the wood is imparted to the whisky being stored in the barrel/cask. Such barrels/casks are called refill barrels/casks (such as 2nd-fill or 3rd-fill). These refill vessels are NOT inherently inferior. Indeed, most distillers go to great lengths to tailor their barrel/cask selection to the style of their whiskies.
As I stated above, minimal use of E150a can be very difficult to discern, especially if the whisk(e)y to which it is added has a bold flavour profile to begin with. Lighter, more delicate whiskies may be more adversely affected.
Do I condone the use of E150a within the whisk(e)y industry. As long as its presence in a whisk(e)y doesn't noticeably change the characteristics (colour excepted) of said spirit, there is no great problem. However, I've encountered more instances than I'm comfortable with where the quantitites of E150a employed DID affect the taste of the whisk(e)y in question. Even such full-flavoured and revered entities as Lagavulin, Laphroaig and Talisker have, on occasion, demonstrated such shortcomings. The effect has more often than not been subtle, but there's no denying I sensed a thin veil that clouded the dynamics of delivery of flavour to the palate.
On the positive side, at least drinkers of such whiskies don't have to worry about what has gone on in the Cognac industry, where liquid wood extract has frequently been added to younger Cognacs (V.S.O.P. or lower) to simulate the 'rancio' effect that greater cask ageing brings to the more expensive ones.