Adding Bubbles to your Hard Cider
By: Denise M. Gardner
At the recent Sparkling Wine Production workshop in PA, our speakers talked a lot about various production methods used to incorporate carbonation into [grape] wine. But what about for a sparkling hard cider?
For base cider production, the objectives are similar to that of sparkling wine: create a fresh and fruity alcoholic product with high acid, good apple flavor, and a clean nose and palate. Nutrient strategies during primary fermentation should be considered by the cider maker, as flaws like hydrogen sulfide (H2S) or general reduction (sulfur-containing off-odors) will diminish the enjoyability of the product. Carbonation has the tendency to enhance the perception of flaws. Therefore, it goes without saying that sanitation is generally very important during this process in order to obtain a clean product suitable for carbonation.
For producers that struggle with obtaining high-tannin apple varieties, sparkling [hard] cider may offer an alternative to the establishment’s product portfolio. In sparkling wine production, low tannin concentrations and perceptions are often preferred, as too much tannin may create a harsh mouthfeel with the additional sensory contribution from the carbonation. This concept may also be applied to sparkling hard ciders.
Malolactic fermentation, MLF, or partial-MLF is determined stylistically by the cider maker. Stabilization including protein stabilization and clarification should be completed prior to carbonation. Dependent on the method of carbonation, sulfur dioxide additions may be required at this step, too.
Dependent on the size and capabilities of the cidery, most sparkling wine production techniques can be utilized by hard cider producers to enhance the carbonation of a hard cider product.
- Bottle conditioning
- Traditional method (Méthode Traditionelle, previously referred to as Méthode Champenoise)
- Charmat, or Tank, method
- Forced carbonation
Bottle conditioning is often used by home brewers as a way to incorporate carbonation in each bottle inexpensively. The concept is relatively simple: add yeast and some additional sugar to each bottle so that the yeast will ferment the sugar while in the bottle. Due to the fact the bottle is sealed, the carbon dioxide developed through fermentation will be retained as carbonation in the bottle. While this is often a preferred method for extremely small operations, the results of this technique are often quite variable, which increases inconsistency amongst the product. Additionally, the resultant product is not typically clear and residual yeast will settle at the bottom of the bottle. Sometimes, this noticeable cloudiness and precipitate is not preferred by consumers. For a good explanation on bottle conditioning, please consider reading this document by Northern Brewer: https://www.northernbrewer.com/documentation/AdvancedBottleConditioning.pdf
The Traditional Method (Méthode Traditionelle) is the common practice that is associated with Champagne production. In this case, carbonation is produced in the bottle by a second yeast fermentation. The difference between this method and bottle conditioning is that the residual yeast is removed through disgorgement prior to the addition of a final sugar and stabilization liquid, called the dosage. This production technique has previously been discussed through the blog post: The Bubbles: Basics about Sparkling Wine Production Techniques, which you can access through the link.
Although many wine fermentation suppliers offer various product addition options for hard cider producers, Scott Labs currently offers The Cider Handbook to make addition decisions easier for producers. Their current product portfolio also features encapsulated yeast products, which some sparkling wine producers have had success in using when utilizing the traditional method of production.
Additionally, this style of sparkling hard cider can use similar equipment utilized by sparkling wine producers.
The Charmat Method (Tank Method) is becoming more popular amongst local wineries, and can also be utilized by sparkling hard cider producers. Here, the secondary yeast fermentation occurs inside a sealed tank and then the hard cider is racked off of the lees into a second pressurized tank. The racked cider maintains the carbon dioxide, carbonation, and the second tank it is racked into can contain the final dosage for the whole volume of hard cider in order to manipulate final sweetness and stabilization. The advantage to this system is that it retains the fruitiness associated with the product and requires less labor compared to dealing with hundreds of bottles in the Traditional Method. The downside to this processing option is the initial cost of processing equipment required to retain pressure inside a tank. As with the Traditional Method, details pertaining to the Charmat Process were previously discussed in the blog post: The Bubbles: Basics about Sparkling Wine Production Techniques.
Finally, one of the easiest methods for obtaining carbonation in your product is through the use of forced carbonation. Some hard cider producers have found success in carbonating kegs of hard cider or working with local wineries that offer carbonation services. With this method, the hard cider should be fully produced, stabilized, back sweetened (if applicable) and filtered by the time it is carbonated.