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In the present challenge, Hollandaise is the topic; and please note that there is a prize to be won (a Springer book of your choice up to a value of €100). Please read on…

Meet the challenge

Today, Hollandaise sauce is made from an initial thermal processing of egg yolks whipped with water. After the mixture whitens and thickens, melted butter is dispersed with a whisk and then lemon juice (or sometimes vinegar), salt, and pepper are added. Hollandaise sauce is closely related to Béarnaise sauce, which is derived from the former mainly by the replacement of water with boiled wine or vinegar, and the addition of tarragon.

Why the name of the sauce - Hollandaise? It is not clear. Some say that the sauce was invented in the Netherlands and then taken to France by the Huguenots, but I have not found trustful sources for this. Others explain that the sauce was invented during the wars of the French king Louis XIV in the Netherlands, but these wars took place during the 1670s, whereas Hollandaise sauce appears in literature as early as in 1651 in Le Cuisinier François written by François Pierre de La Varenne: “with good fresh butter, a little vinegar, salt, and nutmeg, and an egg yolk to bind the sauce” [1]. However, Larousse Gastronomique states that “in former times [before Louis XIV] fish 'à la hollandaise' was served with melted butter,” thus implying that at one time egg yolks were not a part of the designation hollandaise [2].

The challenge

Today, Hollandaise sauce is often used to make Eggs Benedict—the name of which is also controversial [3]. Anyway the modern version of the sauce is interesting for molecular gastronomy because it can fail either when it is heated for too long, or when too much butter is added, both of which can lead to a phase separation. This was aptly summarized by the famous chef Marie-Antoine Carême in 1847: “hollandaise sauce is prone to fail into butter when it waits” [4]. But the failure of the sauce is perhaps not an issue because some chefs say that a smooth appearance of Hollandaise can be recovered simply by the addition of cold water.

Is it true? If so, why?