"Home Processing" of Pistachios.

We hire out our processing. The volume of nuts we deal with is much too large for us to process by hand. However, sometimes we are asked how to process a small amount without specialized equipment. Here are some rough tips.

1. Remove the fleshy hull. This should be done soon after picking (within 24 hrs) so as to avoid staining. It is actually a bit easier after it dries a bit. One tip: wear gloves, eventually the juices can stain your fingers if not washed off.
2. Now you will want to sort the nuts into those that are split, vs those not split. There will likely be blank nuts without a seed in the shell. Discard those and any which are discolored, black ones could have a toxic mold.
3. Now you need to dry the nuts you saved. (You could shell the unsplit ones (this can be tedious) and dry them in the way indicated here.) The typical moisture content is 10-20%; you need to get it to 5%. When they are that dry they are stable; i.e. not prone to rot. (Of course, they should be kept sealed to avoid reabsorbing moisture. A jar with a tight lid or plastic bags work well.) This could be done by drying them outside in the sun, how long depends upon the air temperature. Just mind the birds! We have to cover them with a screen. To check if they are ready, simply sample them: when properly dried they should be crunchy not "soggy". Happily, it is hard to "over-dry" them.
4. Consider using the dried nuts "as is"; the sweet flavor is more apparent than after roasting and salting. You could also use them this way for cooking (the way you'd use almonds or even walnuts).
5. For salting and roasting, try the following.
   • Prepare a salt-water (brine) solution. You don't need much brine, just enough to briefly dunk the nuts in (you can do a little at a time). Add as much salt as you can disolve into the water.
   • After dunking, spread the nuts on a cookie sheet or on a pizza pan. Then place in the oven at 200 F for 20 to 30 minutes. Check them after 15 minutes then every 5 after that to ensure they are fully dried, but not "cooked".
   • You might experiment with other methods, such as spreading them over a mesh-bottomed roasting pan on a grill. Then stir them while they are heated.
   • Broiling has never worked for us -- it tends to burn the nuts before they dry.
6. A note on storage: When the nuts are dried to 5% moisture content then they are stable; i.e. not prone to rot. Of course, they should be kept sealed to avoid reabsorbing moisture. A jar with a tight lid or plastic bags work well. Another tip: for storage beyond a couple of months, you might want to freeze or refrigerate the nuts to slow down the oxidation process and prolong the "fresh" taste.

Good luck!