Home Fermentation

As part of my thesis "Development of a Probiotic Carrot Juice", I have to incorporate probiotics into carrot juice as a cultured product so I am fermenting my own Kefir Water at home. This allows me to gain first-hand experience on whether kefir water fermentation actually works first of all, as well as giving me real time insight into how it works, the conditions required, what can go wrong, how it can be improved or what needs to be avoided. I will also be carrying out microbiological tests and harnessing the laboratory skills learned through past modules in our course to ensure that there is a viable microbial count in the kefir water and identify what these microbes are, comparing the findings to literature on kefir content. These tests yielded that there was in fact yeasts and lactobacillus species present in the cultured water from these grains. 

So to begin the right equipment was required: 

• Glass jar (1 litre)

• Water Kefir grains 

• Non-metallic strainer

• Elastic band

• Cloth

• Water                                                                    

To begin a sugar solution was made up by dissolving normal table sugar (or brown sugar) into water to make up a 5-10% sugar solution, providing the kefir grains with the nutrients they require to ferment the water. This was added into the glass jar with the kefir grains, a cloth was put over the jar and held down with an elastic band to keep out contaminants while allowing the CO₂ to be released. While carrying out this home fermentation I discovered that time and temperature of brewing are very important with good growth being shown between 18-29­^oC for 24-36 hours. Any longer and the flavour becomes tart.

Once the water is cultured it can be strained off and separated the cultured water from the grains with a non-metallic strainer (Metal interacts and damages the kefir grains). It is then ready to be chilled in the fridge and ready to consume! After a while I began to flavour the water with non-sulphur dioxide preservative treated dried fruits (Sulphur interacts with the kefir grains damaging them) to help flavour the water.