Shelf Life Issues

We've been all out of our usual snack nuts for weeks now, and I'm getting desperate for variety in our snacks. I opened a jar of walnuts yesterday -- a food I normally only use for cooking -- and started to munch. But they tasted a bit off, and on investigating more closely, I realized they're starting to go rancid.

Rancid foods are hazardous to your health, so I avoid them as much as possible. Avoiding rancid foods creates a conflict with our goal of storing a year's supply, as many oily foods go rancid faster than that. But according to Diamond Foods, shelled nuts should keep in the pantry for 18 months, or in the refrigerator for 24. The date on this walnut jar is 7/11, which means we've only had them for 8 months. Why are they going bad so soon?

It's hard to predict how long a food will keep, when you don't know how old it already is before you buy it. I tend to think of the origins of store-bought foods as mysterious and unknowable, but that's not entirely true. In this case, we bought the walnuts in mid-summer, and it's a fall crop, so I could have inferred that they were close to a year old already. Not surprising, then, that they're starting to go bad by now. I need to take store-bought foods out of that black box in my head, and remember that they were produced from soil and sunlight on a seasonal schedule, just like the rest of my food.

What to do, then, about preventing walnuts (and other oily foods) from going rancid? California Walnuts makes no predictions about how long they will last, but recommends storing them refrigerated or frozen. Refrigeration would put them in competition for a limited amount of energy-intensive storage space, so I prefer to minimize the need for it, but it is frustrating when food goes bad. We store unopened containers of almonds and oils in the root cellar, and there's plenty of space in there, but it's a lot less convenient.

Another approach would be to mail order direct from a farmer when the new crop comes in, the same way I do with my almonds. That way I would know for sure how fresh they are. We've mail ordered walnuts and pistachios before as an add-on to an almond order, when I was buying from a seller who had all three. But I would have to think about whether it's worth a separate order for something I use in such small quantities.

We could also switch to black walnuts, and harvest them ourselves (we have tons of trees along the stream bed at White Hawk.) That would mean dealing with shelling them, and getting tannin stains all over everything. Might be fun to try once, but I'm not sure I'm quite ready yet to incorporate that into my annual routine.

I guess I'll have to give it some more thought.