Before the routine use of mason jars or even paraffin in the home kitchen, olive oil was often used, in America as well as Europe, to seal air out of jars of vinegar-pickled vegetables. When you’re canning pickles in the modern way today, oil might seem a superfluous addition—if it didn’t make the vegetables look and taste so good after they’re drawn, unctuously gleaming, from the jar.
Once you’ve pried off the lid and stored the jar in the fridge, though, the oil can partially or totally solidify. That doesn’t make for such a pretty pickle. Here’s how Matt, one reader of The Joy of Pickling, encountered this problem:
I’m a beginner to this experience, and have made a few pickle recipes from your Joy book. I have a question relating to a recipe I did of the olive oil pickles (page 98). I did as instructed, and opened around 4 weeks after pantry storage. They tasted amazing! After about a week in the fridge, however, the opened jar formed small, white beads at the top. They vary in diameter, but all quite smaller than the mustard seeds.
The unopened ones do not exhibit this, and I am concerned that there is something wrong. Perhaps this is some congealing of ingredients, but I wanted to see if you’ve encountered similar results. I haven’t eaten them since they’ve been in the fridge (e.g., formed the beads), so am only hoping that the refrigeration is the factor here, and that they are safe to eat.
And here are two photos that Matt sent me:
Sometimes chilled olive oil forms a solid whitish mass; other times it solidifies only partially. The “beads” Matt saw are solidified oil droplets.
The solution to this problem is simple: Take the jar out of the refrigerator a little before serving time, and let the oil melt in the warmer air outside the fridge. In Matt’s case the oil had only slightly solidified, so the melting probably took only ten minutes or so.
There’s something else to remember about oiled pickles: Oil on the rim of the jar or on the lid’s sealing compound can prevent a good seal. So be sure to leave adequate headspace in the jar, wipe any oil off the rim with a paper towel or clean cloth dampened with vinegar before placing the lid on top, and avoid tipping the jars or boiling the water hard during processing.