In the last few months companies have been revisiting the potential of whey, which traditionally is thought of as a byproduct of the manufacturing of cheese and casein. Whey is the liquid remaining after cheese has been curdled and strained. Firms have been looking at how whey - an already healthy product - can be made more appealing to consumers. UK based Reflex Nutrition has used whey to provide a stable protein source on the sports nutrition market. The group said the product can provide 40grams of protein isolate in filtered water. And the firm is confident the complete healthy profile of the product, called Whey Refresh, will appeal to the wider consumer. Karl Schwick, research and account development manager at Reflex, said the firm has worked successfully to remove the natural flavour of whey, which is one of the problems when it came to producing the product. He said: "We found a way to conceal as far as possible the inherently dry taste associated with whey and the stabilizing citric acid. "We could see that attempts to make fruit and citrus flavoured protein ready to drink products (RTDs) had previously failed in providing the market with what we considered was a legitimate and stable protein product. Reflex believe that the proposition of protein in filtered water using natural and nature identical flavourings is ideal in appealing to a mainstream market. " Tetra Pak has provided the firm with pasteurizing equipment, which can produce approximately fifty 500ml bottles per minute. According to latest figures from market analyst Mintel, the sports drink market in the UK was worth at least £137m ($252m, €200m), and is dominated by isotonic drinks like Lucozade Sport, Powerade and Gatorade. In the US, the sports drinks market is reported to have generated almost $3bn (£1.6bn, €2.4bn) with Gatorade dominating the market with 82 per cent of the market. Powerade is a distant second with a reported 13 per cent of the market. The Danish company Chr Hansen last month said it will launch a package of probiotic ingredients which can be added to drinkable whey shots. The firm said the mix would help increase the healthy appeal of the product, as well as masking its normal taste. Whey is comprised of protein, lactose (milk sugar), minerals (calcium, phosphorus and magnesium) and fat. Studies have also linked it to having a positive effect on fighting gut infections.