The difference between taste discrimination and rational discrimination is an important one

That difference being that taste discrimination is doing something because of some prejudice or belief which is not rational, rational being doing that same thing for sensible reasons. The NBA is overwhelmingly black but not because those who hire the players desire higher melanin contents, but because that's just how it works when you select for the ability and desire to play basketball at the highest levels. 

Baseball provides us with another example, as that most definitely was subject to taste discrimination years back. One major reason it ended being that it wasn't rational - teams realised they were potentially losing games, series, because they were not tapping into that talent in the Negro League.

As Gary Becker famously pointed out taste discrimination is costly to those who do it and a free market is one of the best ways of getting rid of it. One of his examples being the Jim Crow laws, they existed because of this very market process. They had to be encoded into the law otherwise the market would indeed compete the discrimination away.

At which point the story about the security tags on ackee:

An angry shopper has accused Sainsbury's of racism after he found £3.80 tins of Jamaican fruit security tagged in a south London store. 

Toby Taylor, 31, said he bet the chain 'wouldn't tag hummus' and slammed it as 'corporate racism'. 

He was shopping in his local supermarket in Penge, Bromley this afternoon when he noticed a whole shelf of the delicacy had been placed in security boxes - despite being reduced and only worth £3.80. 

Supermarkets have excellent information on what walks out the door, that's what all the barcodes, scanning and computer equipment is all about. They also know, as a result, what walks out the door having been paid for and what leaves rather more lightly. Those security boxes are put onto things which tend to leave without paying tribute. They are costly, therefore it is only done to those products where it is worthwhile.

That ackee is more likely to be stolen than lychees  could be a horrible example of all things in our society. But it's not racism on the part of the supermarket.