I’m forever grateful to Benjamin Smith’s blog, The Japanese Kitchen (thejapanesekitchen.com), for its post about pickled cucumbers with shiso leaves. In it, Smith writes that the correct amount of salt to add to vegetables when pickling is 0.035 by weight. So, for example, if you are pickling 1kg of a vegetable, you would use 35 grams of salt. He might not have come up with this proportion, but his blog was the first place I saw it.
There are several methods for making pickles. For most, the first step is to salt the vegetables – this draws out the excess moisture. Salt is essential to all pickles, no matter where (or how) they’re made: you’ll see it used in recipes for German sauerkraut, Korean kimchi, Indian chutney, Italian or Greek olives, French cornichons and Japanese tsukemono.
Usually, when I make such pickles, I scatter a large amount of salt over the vegetables, without weighing it, then wash away the excess. This speeds up the process, because using more salt draws out the moisture much more quickly than if you were to use just the right, measured amount (and I still take the fast approach when I make kimchi).
There are other times, though, when you want to use the salty liquid as part of the brine that flavours the vegetables.
With sauerkraut, you shred the cabbage, mix it thoroughly with salt, then add flavourings such as juniper berries, a bay leaf and caraway seeds, before packing the ingredients into a container to ferment. You need to add exactly the right amount of salt: too little and the cabbage will rot (salt is a preservative), too much and the sauerkraut will be inedible.
The 0.035 amount can be varied slightly. I sometimes use a bit less for pickles that I’ll be eating within a week or so, and which are refrigerated soon after the fermentation process starts. I’ll use a bit more (along with some sugar) for pickles that have a large amount of chilli, to balance the heat.
The 0.035 proportion also works for pickled meats and seafoods, which should always be refrigerated immediately, for safety reasons.