Sterilising might sound like a tricky task, but it simply requires heating something to a point where no bacteria can survive. Sterilising jars when making jams, chutneys and preserves is an important step to prevent all of your hard work spoiling due to a buildup of harmful bacteria.
If you are using jars with rubber seals, be sure to remove these before placing in the oven. When adding food to the jars after sterilising, it is necessary that both the food and jars are at the same temperature so that the jars don’t crack.