Sauce Béarnaise.

Abstract

Although Small and Bernstein* are to be congratulated for contributing to the literature in a field that has received inadequate attention, they failed to mention several points long familiar to those with culinary experience, in their article in the April 5 issue of the Journal. First of all, not only is acetic acid "not essential for reconstitution of sauce Béarnaise," as the authors noted, but their experiments yielded a result obvious to anyone familiar with a close relative of Béarnaise, sauce Hollandaise: acetic acid is not required for the formation of a homogeneous suspension of butter in egg yolk! To the extent that acid is added to Hollandaise, in the form of lemon juice, it is for taste only and is usually added after the emulsion is formed (a proper Hollandaise may contain no lemon juice, despite the excessive quantities one so often encounters in this country). Thus, any primary role of pH in the formation of the suspension could have been ruled out without doing the experiment. When this result is combined with the experimental finding that pH does not influence the temperature at which the system separates, it is clear that any role of adsorbed surface charge is negligible. What must be considered, instead, is the abundant presence of charged phospholipids in the egg yolk that contribute to the repulsive forces between micelles. Concerning the role of pH in the onset of scrambling, it is almost trivial to say that irreversible denaturation of the egg protein will be pH dependent, if one knows the role of weak electrostatic interactions in the three-dimensional conformation of the protein molecules. But the pH in this instance still does not affect the intermolecular forces responsible for the suspension, since flocculation has already occurred. Finally, the authors indicate that the aqueous phase necessary for the emulsion "can be supplied by pure water or other aqueous medium." Again, had the authors considered sauce Hollandaise, they would have realized that the necessary water is supplied by the egg yolks, which are about 50 per cent water by weight. Edward H. Egelman Brandeis University, Waltham, MA 02154