Why is cheddar cheese orange?

After doing some research on cheese, I discovered that orange cheese is a slightly different story. According to cheese historians, the colour originated many years ago in England. Cow's milk contains varying amounts of beta-carotene, the yellow-orange stuff found in carrots and other vegetables. Milk from pasture-fed cows has higher beta-carotene levels in the spring and summer, when the cows are munching on fresh grass, and lower levels during the fall and winter, when they're eating hay. The natural color of the cheese varies over the course of a year, so cheese makers began adding coloring agents.

Nowadays the most common of these is annatto, a yellow-red dye made from the seeds of a tree of the same name. Dyeing the cheese covered over seasonal colour fluctuations and also played into the fact (or anyway the belief) that spring/summer milk had a higher butterfat content than the fall/winter kind and thus produced more flavorful cheese.

Figuring that if yellow is good, then orange must be better, some cheese makers began ladling in the annatto in double handfuls, producing cheese that looks like orange playdough. In recent years some smaller operations have rebelled and stopped using colorants. According to one cheese-making text, uncolored cheese is a "sordid, unappetizing melange of dirty yellow."

Don't believe it. That shade of orange has little to do with butter or cheese.

Obviously (as noted elsewhere) this depends on what you understand as "cheddar", and is likely to lead to snorts of derision from Brits; however, although colourings are not added to high-quality English cheddar cheese (or as far as I know to the New Zealand or Canadian varieties which dominated the British market before the UK entered the EU in 1973; during that period, when British food did its best to fulfil its reputation for appalling blandness, acidic Canadian cheddar was one of the few things that actually tasted of anything. But I digress.) there is in fact a fairly healthy traditional market for red cheddar in north-eastern England (roughly speaking, east of the Pennines and north of the Trent); this is mild creamery-produced stuff of no particular merit.

However, other traditional English cheeses of better repute are coloured orange (the dye of choice being carrot juice or industrially extracted beta-carotene which also incidentally goes under the name of vitamin A; as far as I know annatto is only used in industrial-scale production) to varying degrees. These include:

• Red Leicester - a mild cheese, not vastly dissimilar from cheddar, good for toasting. Virulently orange.
• Cheshire - comes in both red (a milder pink in fact) and white variants, a crumbly acidic and fresh-tasting cheese.
• Shropshire blue - a fairly firm blue cheese, milder and much less astringent than Stilton; oddly, one of the few British cheeses which has been successfully marketed elsewhere in Europe. Also comes in a white variety but the orange one is more common.

An orange processed cheese supposedly originating in the UK (and I believe manufactured by Kraft) which appears to be similar to American cheddar (which I've never tasted) is marketed in Belgium under the name "Chester"; its availability here supposedly dates back to the stuff brought over for the British troops on the Western Front in World War I, but I doubt that they actually had anything quite that plasticky.

It should be noted that the British have been very slow and late getting into the controlled labelling of origin thing, so very few of the names offer any particular guarantee of authenticity; cheddar in particular has been officially decreed to be a generic term usable by producers anywhere.