It's a miracle...sorta

Miracle fruit brings a change in taste › Dr Karl's Great Moments In Science (ABC Science)

While in Canberra on holiday we went to Questacon, the gigantic kids' science centre, and in its shop I found "miracle fruit" tablets.  We gave them a try last night at home.

This red berry fruit has featured on some TV programs in the last few years, and an interesting account of what they do (make sour acid things like a lemon taste sweet) is at the link above.  The thing you buy at the shop is a biggish tablet made from the dried pulp of the fruit.

The effect really is interesting to experience, not just because it makes lemon taste entirely palatable (to the detriment of your tooth enamel no doubt),  but because (as Karl says) it makes it taste really intensely sweet, rather as if you have popped a few saccharine tablets on your tongue at once.  And the effect seemed to last quite a long time.   Normal sweet things aren't much changed in flavour.

I was interested to read in Karl's account that in the early 1970's, it was hoped that it may be used as an artificial sweetener of sorts:

It took until 1968 for two separate groups of scientists to isolate the active ingredient. It turned out to be a chemical that was mostly protein with about 191 amino acids, and about 14 per cent carbohydrate (sugars such as mannose, galactose and fucose). The active ingredient was given the name 'miraculin'.

Soon after miraculin was isolated, Robert Harvey, an American biomedical postgraduate student, became aware of its wonderful property. 

At the time, the artificial sweeteners (which have sweetness, and virtually zero kilojoules) had a slightly noticeable after-taste. 

But Robert Harvey realised that miraculin did not. He tried mightily to market it as an alternative sweetener, one that was based entirely upon a natural product. 

But in 1974, just as he was about to launch it, the US Food and Drugs Administration refused to classify it as 'generally recognised as safe', despite the West Africans having eaten miraculin for centuries with no problems. 

Robert Harvey could not afford the several years of testing needed, so miraculin never made it into the marketplace.

All rather interesting...