Pitfalls in the design and manufacture of infant formulae

The composition of modern infant formulae is basically oriented on the "golden standard" human milk and influenced by several official regulations and recommendations (EC, ESPGAN, etc.). This article will focus on two recent improvements in the field of long-chain polyunsaturated fatty acids (LCPs) and protein hydrolysates. The addition of LCPs for preterm formulae was recommended recently by ESPGAN (the European Society for Pediatric Gastroenterology and Nutrition). Our research has focused on this problem for many years and we have found a good source of LCPs using specially prepared egg-yolk lipids. Others have used fish oils and run into the problem of growth retardation. Therefore, the possible sources of LCPs have to be discussed very critically and the alternatives will be shown. Also, new developments like the use of single-cell oils will be discussed. Second, the use of protein hydrolysates have been introduced for the so-called hypoantigenic or hypoallergenic formulae. Hypoantigenic formulae for preventive use have to be differentiated clearly from hypoallergenic formulae for treatment of proved cows' milk protein allergy. The problems of designing suitable hydrolysates that are low in antigenicity and good in taste will be outlined. The determination of the molecular weight distribution by gel chromatography will be compared critically with the newer techniques. The ELISA technique for testing the antigenicity is recommended before any in vivo evaluation. So far, the anaphylactic guinea-pig model is the most sensitive in vivo testing method. Summing up, modern infant formulae manufacture is much more dependent on modern laboratory techniques, which have to be chosen critically and must be adapted to the newest state of the art.