The 4 Spoilers

  • When making preserves good hygiene is essential. There are four micro organisms known as ‘spoilers’ which if they make their way in to your preserve will ruin them and make them inedible. The four spoilers are Enzymes, Bacteria, Mould and Yeast. These are not things which you need to be frightened of provided you follow the simple rules given below you will avoid these spoilers and be able to enjoy your homemade produce.
  • First we will tell you a little about the four spoilers and then we will tell you how to eradicate them.
  • Enzymes:
  • These are proteins which are found in all living things, animal or vegetable. Enzymes are catalysts which trigger change such as deterioration i.e. when damaged fruit or vegetables start to discolour.
  • Enzymes are most active at temperatures between 29 and 50 degrees however they will be destroyed at temperatures over 60 degrees.
  • Bacteria:
  • Bacteria are only visible under a microscope, they increase rapidly at temperatures between 20 and 40 degrees but are destroyed at temperatures over 100 degrees. Bacteria cause food to rot so it is vital that these are destroyed during the preserving process.
  • Mould:
  • Mould spores will settle on any fruit and vegetables and start to form a green/grey cotton wool like appearance on the surface. Mould thrives at temperatures between 10 and 38 degrees but can be destroyed at temperatures between 60-90 degrees.
  • Yeast:
  • Yeast when found in food is generally not harmful to our health but it can cause food to spoil. Most yeast will grow in food containing over 60% sugar if it is badly covered allowing air to get to it but it can be destroyed at temperatures above 60 degrees.
  • Having described the four spoilers you are now aware of them but do not worry, there are ways to avoid them and eliminate them from your preserves. Just follow these simple guidelines.
  • 1) Hygiene: all equipment and work surfaces need to be thoroughly cleaned and jars which will be used to store your preserves, once made, must be sterilised.
  • 2) The use of high temperatures is paramount in destroying these spoilers so it is an integral part of the preserving process. The Kilner jam pan, funnels and jars can withstand the required high temperatures making them the ideal tools for the job.
  • 3) The high concentrations of either sugar, acid, alcohol or salt in preserve mixtures serve to kill off the spoilers.
  • 4) The final step is excluding air from the finished product. Kilner jars are ideal for created an airtight vacuum seal provided you follow the filling and closing instruction provided. See Making your first Preserve
  • Provided you follow these guidelines along with your recipe your preserves should remain ‘spoiler’ free.
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