Fish and meat can be pickled using the citric acid from limes and lemons. Dilute juice and water 2:1, mix well and soak the flesh for at least 12 hours. Transfer it to an airtight container with enough solution to cover meat. Vegetables can be preserved by boiling and then keeping in saltwater. To make sure brine solution is strong enough, add salt until a potato or root vegetable will float in it. Another method of using salt is to tightly pack layers of salt and vegetables. Wash of the salt when you need to use them.