Friday, May 4, 2012
Preserving: Freezing Asparagus
I did a fair amount of food preservation last year, between extensive freezing and learning boiling water canning, but since I was a newbie, I didn't feel confident explaining things on the blog. Not until I knew they would work, that is. This year, now that I am brimming with confidence, I feel ready to impart my wisdom to the world. Watch out.
What better place to start than with one of my very favorite vegetables? Asparagus has a lamentably short season, so I end up eating it almost every day while I can get it. This year, I was determined to freeze some and extend my enjoyment.
I've had mixed results with freezing vegetables. Last year we froze tons of green beans, but they tend to come out soggy and gross. They're fine for soups, but not for eating on their own (it brings me back to the soggy frozen vegetable side dishes of my childhood - apologies to my mom). But I had fantastic results from the bell pepper strips I froze on a whim at the end of the season, when I had more peppers than I could possibly handle. The texture wasn't bad at all and they're useful in so many more sorts of dishes than green beans. So I don't think the problem is freezing - I think it lies in the vegetable itself.
The internet tells me that asparagus should freeze well. I did find one site where someone complained that theirs always comes out soggy. The comments suggested that the method of freezing was the problem. Sogginess is caused by the formation of large ice crystals which break down the cell walls of the plant. To avoid sogginess, you need to facilitate the formation of smaller ice crystals. That means freezing the product quickly. To do that, it should be as cold as possible before going into the freezer. (I only went halfway in this department, so we'll see how mine come out.) Also, any vegetable you freeze should be parcooked beforehand because it kills off some of the enzymes that would otherwise cause the product to break down (I didn't cook my bell peppers and this was not a problem, though we went through them within about three months, so maybe this would have taken effect later).
So. To the asparagus.
I went out to Terhune Orchards yesterday morning to pick my own so that it would be as fresh as possible. (Sidebar: Asparagus is the weirdest vegetable ever. It just emerges from the ground the way you eat it - there's no development or growth, just crazy big stalks slowly rising from the earth like Athena emerging from the head of Zeus - this picture will show you what I mean.) I picked about two pounds for my trial run.
When I got home, I set a large pot of water boiling (think, the same amount of water you'd use for a batch of pasta). Meanwhile, I washed the asparagus to get the dirt off, then snapped off the woody part of the stems. I split the stalks into two batches to ensure I wouldn't crowd my pot. Then I chopped the first batch into 2-3" lengths.
When the water was fully boiling, I popped the slices in and cooked them for 2 minutes.
While they were cooking, I pulled out a very large bowl and filled it with ice water. When the asparagus was done, I skimmed the pieces out and put them in the ice bath to stop the cooking process. While the water came back to a boil, I chopped the next batch and then repeated the process.
When all the asparagus was cooked and cooled, I poured them into a strainer and then dumped them onto a dish towel. I used another dish towel to pat the tops dry. Before the pieces warmed up too much, I arranged them on a baking sheet lined with parchment paper and slid them into the freezer (if you really want to get them cold, you can pop them into the fridge for a bit first, but mine were still pretty cold from their ice bath, so I skipped that step). You should spread them out so they have room to freeze quickly, but I couldn't fit a second tray in my freezer, so I just let them be crowded.
Once they are totally frozen (I left mine in the freezer overnight), remove them from a baking sheet into a freezer bag. They should last about six months in the freezer - make sure to label and date your bag!
Everything seemed to go well for me, but I'll update you on the results when I use them. But don't hold your breath - that won't be until fresh asparagus season is over!