Of course I found this blog because I searched for “pesto turns brown”. I’ve been making pesto and freezing it for later (winter) use for years. I have ALWAYS had it discolor a bit but it always turned dark green, I was used to this. But this years “batch 1″ turned brown as soon as it hit air and did so even more quickly once it hit the hot pasta. Yesterday I used some of frozen batch 1 and got the same brown color. Freezing does not help. Tastes OK though, as good as frozen can taste and still better than anything that I have found ready made in a store.

So I have to ask myself what was different in batch 1?

The basil was different variety than normal. Almost adult plants were available cheap so I got 3 pots.

Much of the basil was older on the plant than I usually use. A bit tougher. The stems of the plant were just beginning to turn “woody”.

I used less spinach (normally 30% to 40 %), just a bit. I like to use spinach partially because it seems to add to the color…and the kids need it!!!

I remember being in a hurry and not drying the basil as well as usual after washing. I thought while making batch 1 and seeing turn brown before my eyes while doing so that this had something to do with it.

I don’t like the idea of adding ascorbic acid regardless of form, lemon juice or straight vitamin C but may try this to see if I can preserve the color with out altering the sweet taste of the pesto I like. I use pecans instead of wall nuts specifically for their relative sweetness over sometimes bitter wall nuts. There goes my secret ingredient!!!!

I recently read the ingredients of the COSTCO brand and it has some kind of vinegar in it, maybe to help with color preservation? That was enough for me not to try it.

I will likely try the blanching idea to see how it works out.

Unrelated pine nut tip:

As all us pesto makers know, pine nuts are EXPENSIVE. And the price has gone up dramatically lately, so much so than many suppliers currently do not carry them. Add to that the “oxidized pine nuts” controversy of Chinese products and you have a real problem.

I can’t do with out. I add some roasted to the pesto I make and add liberal amounts of whole roasted pine nuts over the finished dish.

So I found a place on Amazon that was selling 2 pounds of pine nuts for some ridiculously low price, it was less than $ 33.- including shipping, and they got here a few days after ordering. I thought even if these are oxidized Chinese pine nuts, it’s worth a try since this would have only gotten me a few ounces at the local store.

The first order got here and was so darn fresh the nuts still smelled like a pine tree. No oxidation. Just good product.

I thought maybe I just got lucky. But the next batch I ordered a month and a half later was just as good. Nuts were were smaller but just fine.

Not everyone who has ordered from them was as happy as me by the feedback they left but I sure was!!!. I won’t mention the name of the place, you can figure it out. Just though I’d share.

I use the leaves raw (ie, unblanched), plenty of garlic, and walnuts rather than pine nuts, as we prefer the taste – and don’t mind that they’re also cheaper! My BIG change is substituting chicken broth for half (or more) of the olive oil called for – makes it much less rich and oily, and more palatable for spreading on a cracker or sandwich. Try it, you may like it better, too!

Then last night, a very COLD January night here in Washington, DC, I got the urge for the summery taste of pesto, but had used up my freezer stash, so I used some fresh basil that I found at Whole Foods in one of those plastic boxes. Same recipe as always, except that I used almonds instead of pine nuts since that’s what I had, and guess what? It did not turn brown and what’s left over today is still bright green!

SO – the question is: Might it be that the store-bought basil was a different variety of basil than what I’ve been growing and might that have made the difference?

MY VARIATION: Add an equal amount of fresh spinach (this year I found a great source from a local organic farmer) and save a few pennies by substituting walnuts for pine nuts. Result: Friends ask for batches…