Friday, July 2, 2010

Strawberries + lN2 = SCIENCE!

I don't think I've yet blogged about our amazing neighbours next door. When we moved in, they came over with a plate of cookies. Later we learned that they also loved board games. We borrow each others' stuff (ladders, rakes, etc) and occasionally have dinner together. They are awesome neighbours. The wife invited me to go strawberry picking. I LOVE fruit picking. I think it's mostly about the bargin I get (usually half the price of stores, PLUS I don't have to settle for a few crappy fruits at the bottom of the container), but I also enjoy getting outside and doing something different.ANYWAY, so I may have gone a *little* overboard and picked a few too many quartz of strawberries. I made strawberry rhubarb crisp (still tuning the recipe) and strawberry jam (don't skimp and buy No Name brand pectin, it's worth the extra few cents for brand name) and then I sort of ran out of time. Solution? Freeze the rest.The most common way to do this is to first hull the strawberries. I also removed the centers of the very large strawberries. To do this, I use a jagged-edged iciing tip: Push in, twist, pull out. Simple. Next, you would arrange them in a single layer on a heavy-duty baking sheet and place it in the freezer. The goal is to freeze them as quickly as possible. This way, you'll get smaller ice crystals. Large ice crystals are bad because they will tear apart the cell wall of your strawberries so that, when you thaw them, you get strawberry soup.

The best way to freeze strawberries is to drop them, individually, into some liquid Nitrogen (lN2). lN2 has a temperature of -162 degrees Celcius. (Recall that there is nothing hazardous about lN2 (except for its temperature) as N2 accounts for 78% of the air we breathe.) This is how the big companies that sell frozen vegetables and fruit at the supermarket do it.

And it's also how you would do it if your husband were a physicist who works with the stuff on a daily basis to cool his scary-powerful lasers. *big grin*
Freezing the strawberries was a lot of fun and I look forward to the next fruit-freezing opportunity (unfortunately, raspberries are a little small and time-consuming to pick any appreciable amount). I did learn one lesson though: Don't dare your husband to eat a recently frozen strawberry. He'll do it, and then you'll have a whole tongue-frozen-to-flag-pole ordeal ahead of you. :P