The glass demijohn is best to use for small quantities such as 4.5
litres (1 gallon). It leaves just sufficient air space as it actually has a volume for nearly 5 litres. For larger quantities, the next size is a 25 litre fermenter, which are made from high density plastic material.
Depending on the quantity being made, with the majority of country wines, they need to be fermented first in a high density white plastic bucket (with lid) before being transferred to a demijohn or 25 litre
wine fermenter. Currently the various bucket sizes available are 10, 15, 25 and 60 litre capacity (2, 3, 5 and 13 gallon).
The buckets used MUST
be food grade and made from clear or white high density plastic. Coloured plastic buckets frequently contain dyes that are toxic, and therefore must not be used.