Yolk on Our Face
Okay, so we admit it. We read your comments, sometimes. And thus, this post is for you, Gene.
First, a clarification. The egg yolks in the center of the moon cakes that prompted your concern, and presumably the concerns of many others (statistically, for every letter written to a congressperson, the government assumes 9, or 99, or some other amount of people feel the same way — and so shall we), are not raw.
Moon cakes contain cooked egg yolks, recalling the shape of the moon. We apologize for not being clearer about this detail.
Also -- Gene's supporting point, regarding mayonnaise and spoilage, got us thinking. We vaguely recall Chef Lars at telling us in our Introduction to Professional Cooking class that mayonnaise keeps for at least a week on the countertop. Now we would never hold him to this in a court of law (for one thing, our brain is a tad unreliable in the memory department, and plus we can't find that advice in our old, yellowing notes), but the thought did prompt us to take a wander around the Internet on the topic, where we found this NPR feature, debunking the myths about mayonnaise on its 250th birthday.
SFist Julie, contributing. After the jump, the truth about mayonnaise, and the dreaded.... potato salad!
Commercial mayonnaise, which uses pasteurized egg yolks, is certainly safer than homemade — if you're going to play room-temperature roulette with your condiments. Equally important is the acid (usually from the lemon juice or/and vinegar) in most mayo formulations that thwarts health-threatening bacterial growth. Again, commercial processors are more likely than you to get the proportion of acid right; we are NOT advising that you try this at home.
Still, the fact of the matter is that your tongue will suffer before your tummy, according to the NPR interview. Says microbiology professor Michael Doyle, Director of the Center for Food Safety at the University of Georgia:
"There's an old wives' tale that mayonnaise being added to perishable foods will cause food poisoning. That's not true. Acid is added to mayonnaise to prevent these bad bacteria from growing and producing illness. However, there are certain types of microorganisms — such as molds and other types of bacteria — that can spoil mayonnaise... So once mayonnaise has been opened, it's important to refrigerate it so that the spoilage bacteria don't grow and cause 'off flavors.'"
Coincidentally for us, the potato salad myth that Dr. Doyle refers to was also recently referred to in a minor episode-long gag last week on The Office.
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