As someone working in a connected industry let me reassure you that the colour of the hose is completely irrelevant. The most important factor is that that hoses being used for the delivery of potable water are identifiable as "FOOD GRADE". Such hoses are available in many colours, blue, red, yellow, green and multi coloured. In many cases WRC certified food grade hoses will be marked as such along their length and so this is probably your best guarantee that you're buying a safe product. A food grade hose will usually incorporate an inert Polyethylene liner and will contain no Cadmium, Barium or plasticisers. And it's the plasticisers in regular garden hoses which are responsible for that classic caravan tasting tea!
Another factor to consider is the hose should be reinforced. This is typically a "knitted" layer bonded within the outer casing of the hose and is either visible through the transparent outer layer or it may be noticeable as a criss cross texturing to the outer surface of opaque hoses. Some camping/caravaning accessory suppliers sell nice shiny bright blue 1/2" hoses by the metre. Whilst these look very pretty they do not have any reinforcement. Only this year I saw a caravanner using a 10m length of this for his mains water kit whilst in the Dordogne. In temperatures of 80 degrees and with high water pressure the hose got fatter by the day until the inevitable happened and it split along its length flooding his pitch.
So, my advice to you is this, select your hose carefully, disregard the colour, ensure it's marked along it's length as food grade and look for one which incorporates reinforcement. That way you'll know you're drinking safe water, your tea will taste wonderful and you can sleep peacefully knowing your pitch won't be flooded in the morning. And the really good news is quality hoses often cost no more than poor ones masquerading as the real macoy .