Hypoallergenic formulas are processed by enzymatic hydrolysis of different protein sources such as bovine casein/whey and soy followed by further processing such as heat treatment and/or ultrafiltration, or they are based on amino acid mixtures. The products have been classified according to the degree of protein hydrolysis as extensively or partially hydrolysed protein products. But hypoallergenic infant formulas are significantly more expensive than either milk based or soy based infant formulas. In addition, their taste is altered significantly during hydrolysis of the protein and they may not be well accepted by some infants.