"One must not go too far, however. The farmers know very well that the cream of a whole week gives a butter of unpleasant flavor.
"It is therefore the uniformity of fermentation that ensures uniformity in the production of butter; which explains the importance of this question."
Another writer, V. Houdet, Ingénieur-Agronome, Directeur de l'Ecole Nationale des Industries Laitières de Mamirolle, says in his book "Laiterie, Beuerrerie, Fromagerie" (fourth edition, 1912):
"No matter whether the cream has been obtained by letting the milk stand in a low temperature or by means of a separator, it does not, if churned at once, yield anything but a sweet butter, of pure taste but without bouquet and without finesse.
"In order that the butter may have the aroma, and particularly the nutty flavor which the consumers desire and which considerably increases its market value, it is necessary that the cream should ferment, should become soured, before it is churned, for it is particularly on this treatment, this maturation (ripening), that all the qualities of the product depend.
"While the cream is fermenting, the sugar of milk it contains is changed into lactic acid which reacts in the measure of its production on the glycerides, saponifies them while liberating the volatile acids which impart to the butter its perfume and make it keep better.
"At the same time, as with all fermentation, it is necessary to stop in time; an excessive development of acid would yield a strong butter, rapidly undergoing a change and becoming rancid."
Director Houdet also points out, as did Professor Allard, that by souring the cream the yield of butter is "very appreciably increased."
Judging by these remarks, the French way is like the American: the cream is ripened (soured) before churning. Must we, therefore, conclude that the enormous difference (apart from the salt question) between the average American and the average French butter is due chiefly to American carelessness in regard to a number of details, particularly the degree of acidity and the regulation of the temperature which the French authors just quoted declare to be of the utmost importance in the manipulation of the cream while ripening?
Or is our butter usually so inferior because so much of it is marketed after undergoing cold storage, whereas the French get theirs fresh, as they do their poultry? Years ago the State Railway began to run special butter trains from Normandy, Brittany, and the La Rochelle district, which reach the Paris market early in the morning, refrigerating cars being used in summer, so that the butter always arrives in perfect condition.