As an expert sommelier and brewer, I can confidently say that not all hard cider has yeast. Yeast is an essential ingredient in the fermentation process of cider, as it converts the sugars in the fruit juice into alcohol. However, there are different methods of producing hard cider, and not all of them involve the use of yeast.
Traditional cider-making involves allowing natural yeasts present on the apple skins or in the surrounding environment to ferment the apple juice. This method is often referred to as “wild fermentation” and can result in a more complex flavor profile in the final cider. The natural yeasts will begin the fermentation process on their own, without the need for added commercial yeast strains.
However, some cider producers opt to use commercial yeast strains to ensure a more controlled fermentation process. These strains have been specifically selected for their ability to produce desirable flavors and aromas in the cider. By using commercial yeast, cider makers have more control over the fermentation process and can achieve consistent results from batch to batch.
Additionally, some cider producers may choose to pasteurize the juice before fermentation, which kills off any yeast present. In this case, they will need to add their own yeast to initiate fermentation. This method allows for a more predictable fermentation process and can help prevent off-flavors or spoilage.
It's important to note that even if yeast is not intentionally added to the cider, there may still be residual yeast present in the final product. Yeast is a natural component of the fermentation process, and some strains may remain in the cider even after fermentation is complete. These residual yeasts can contribute to the flavor, aroma, and overall character of the cider.
While yeast is a crucial component in the fermentation of hard cider, not all ciders are made with added yeast. Some ciders rely on natural, wild fermentation, while others use commercial yeast strains. Regardless of the method used, yeast plays a significant role in shaping the flavor and character of the final cider.