For a hobby last year I started making cider (hard cider in the US). Below are some of the demijohns of apple juice I fermented.

I cracked open a finished bottle and it looked & smelt great, but the taste…. it was insipid, slightly acidic and low in alcohol. Not good. Being in the business of continuous improvement and this being my second year I am ready to develop my manufacturing process.

I have researched the issues and my proposed solutions are.

  • Insipidness: I believe was due to using just eating apples, it should have been a blend of eating, cooking and crab apples. Here is a sample of my raw materials

  • Acidity: I have my pH tester and acid reduction solution.
  • Alcohol: I have my hydrometer and bag of sugar to up the alcohol content.

So the question is what makes the perfect product? What better than to design an experiment. Being by no means an expert in the practical design of DoE, here is my endeavour. The factors & levels seem to be:

Factor Levels
pH reading Two levels. Initial pH of blend or set to pH of 3.8 (which is highest recommended level)
Sugar content Two levels. Initial natural sugar content or adjusted to give final product of 7% alcohol
Apple Blend Tricky, I want to try different combinations but not at the extremes of 100% of any one. I would like to get my blends by having variations of eating apples from 40 to 80%, cooking apples from 40 to 80% and crab apple from 0 to 20%. Not sure on this bit yet, could do with some help

The output will be taste tests scored from 0 to 10. I have a limited number of trails as I only have 8 demijohns. this should create the product to scale-up next year.Any tips on the best design to ensure I get good results?

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