Glossary · Microbiology
Wild yeast
Also written indigenous yeast, native yeast. Each is a name for the same thing, which is why none of them has an entry of its own.
Definition
Yeast arriving with the fruit and resident in the press house and its equipment, as opposed to a pitched commercial culture. The term covers both useful and spoilage species.
- Subject
- Microbiology
- Also written
- indigenous yeast, native yeast
In more detail
Studies of wild cider fermentations consistently find that much of the resident population comes from the equipment and building rather than from the orchard, which is why a long-established cider house has a genuinely distinctive microflora and a new stainless-steel one does not.
Where this is covered properly
The glossary defines; these pages explain. Each is described in its own words.
Related terms
Terms that belong to the same part of the subject, or that this one is routinely confused with.
Fermentation
Wild fermentation
Fermentation by the yeasts already present on the fruit and in the press house, without a cultured inoculation.
Microbiology
Apiculate yeast
Lemon-shaped, weakly fermenting yeasts — *Hanseniaspora* and its anamorph *Kloeckera* — that dominate the first days of a wild cider fermentation before alcohol suppresses them.
Microbiology
Microbial succession
The orderly replacement of one microbial population by another during fermentation, as rising alcohol, falling sugar, falling nutrient and falling oxygen change which organism can compete.
Microbiology
Brettanomyces
A genus of slow-growing yeasts, *Dekkera* in its sexual form, that survive in wood and in finished cider and produce volatile phenols smelling of farmyard, leather, spice and sticking plaster.
Faults
Film yeast
Aerobic yeasts, chiefly *Pichia* and *Candida* species, that grow as a dull white or grey film on the surface of cider in a part-empty vessel, metabolising ethanol and acids.
Where to go next
- Cider glossary — The whole vocabulary, by subject and A–Z.
- Comparisons — Terms that are only really clear when set against the thing they are not.
- Search — Finds terms by their aliases and by their spellings in other languages.
Sources
What this page rests on. Where a source is marked as registered rather than read, CiderHQ is recording that the body is authoritative on the subject without claiming to have worked through the document itself. See our evidence policy for what each state means.
Peer-reviewed literature on cider fermentation microbiology
Various journals · peer-reviewed literature · registered as competent for this subject
Covers the microbial succession of spontaneous cider fermentation, the role of non-Saccharomyces yeasts in the early stages, malolactic conversion by Oenococcus and Lactobacillus species, and the organisms behind the principal spoilage faults.