Does anyone out there have a trick for keeping freshly made pesto from oxidizing and going all army brown in 15 seconds? When storing any leftovers in the fridge, I top the pesto with a thin film of olive oil and this seems to work pretty well, but when I serve it tossed with pasta or spooned on a fresh tomato slice, it goes all funky in a hurry. It almost always stays a vibrant green when I order a dish with it in a restaurant, so I know there must be a trick....anyone? Thanks.

Oui, Chef


Kitchen B. October 15, 2010
Oui Chef, just to add that lanching works a treat (already said) - but its the same trick you used on cilantro in your roasted red pepper soup. BTW, I discovered that the blanched cilantro has a more pronounced taste, something perhaps to do with the essential oils (if any) loosening.
violist October 14, 2010
I remember a tip that I think Michael Chiarello mentioned years ago, which was to crush a plain Vitamin C tablet to a dust consistency and add that to your pesto. He claimed it would keep that vibrant color after months of being frozen or weeks of being refrigerated, and that it didn't affect the taste. He also added the thin film of you've been doing.
foodfighter October 14, 2010
Definitely a little spinach/parsley helps keep it green. Per Harold McGee here are a few other ideas.

-Use leaves only, not stems or stalks;
-Cook the pasta in water acidulated with lemon juice (1/4 cup per quart) or cream of tartar (1 1/3 tablespoons per quart). This prevents the basil enzymes from acting on brownable substances in the pasta, but makes the pasta tart;
-Use pine nuts, not walnuts.
Hilarybee October 14, 2010
I blanch the basil leaves and put lemon juice and zest in the pesto. Sometimes I'll do half arugula/ half basil or half basil/half spinach.
jdeslaur October 14, 2010
A spot of lemon juice?
mrslarkin October 13, 2010
That is a great tip!!
Oui, C. October 13, 2010
Thanks DonnyG, and to TiggyBee and AntoniaJames for their concurring opinions. I wondered if this might be the trick as I've blanched numerous other greens to help them keep their color, but always thought basil had to be kept raw for an authentic pesto taste / texture. Still got a bunch of basil in the garden, and will be putting this good advice to use tomorrow! Thanks again - S
AntoniaJames October 13, 2010
Yes, DonnyG is absolutely right. To my knowledge, there is no other way. ;o)
TiggyBee October 13, 2010
DonnyG's answer is spot on. In addition to blanching the basil, I add fresh spinach too, for extra green.
anyone October 13, 2010
Blanch your fresh basil in hot water just for a moment. Cool under cold running water and then make pesto. Be sure to use your oil trick and keep it air tight when storing.
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