The final stages of Traditional Method sparkling wine production involve the  two step process of riddling and disgorgement to clarify and remove yeast deposits from secondary fermentation. Disgorgement is typically straightforward if the deposit collects properly in the neck of the bottle so it can be ejected. The riddling stage is more critical and dependent on the quality of the base wine and the success of the secondary fermentation. If the deposit remains in suspension or does not compact sufficiently it will result in a cloudy wine when disgorged that is unfit for sale.

Important factors to consider

  • Bottle shape – the Champagne style bottle is perfectly suited to collecting deposits. However, some modern bottle shapes are unsuitable for automated riddling equipment making it difficult if not impossible to hold in a riddling cage.
  • Quality and characteristics of the base wine needs to be controlled – colloidal instability (protein and metal) leads to casse in the bottle, disrupting the deposits properties and resulting in riddling problems or gushing bottles. In addition, potassium and calcium tartaric stability needs to be monitored.
  • Microbiological stability of the base wine is crucial – dosage of adjuvant is directly linked to the microorganism population present during fermentation in the bottle 
    – > 8 x 106 CFU/ml and adjuvant dose too low = greasy sticky deposit and difficult riddling
    – < 8 x 106 CFU/ml and adjuvant dose too high = too large a deposit for a successful disgorgement
    – MLF in the bottle also increases the overall microorganism population and adds different cell morphology, resulting in large, sticky deposits and very difficult riddling.
  • Riddling adjuvant application – the adjuvant should ideally be the last component added to the tirage tank. This enables the yeast to be coated by the adjuvant and therefore will not stick as much to the glass.
  • Base wine viscosity – if it is too high, it impacts the speed of yeast sedimentation or even ‘blocks’ it leading to a cloudy wine. A pectin/glucan test before bottling is recommended.

Choosing a riddling aid

Riddling adjuvants are technological aids that were developed at the same time as the automation of riddling. Their purpose is to facilitate yeast sedimentation into a compact deposit so it can be removed effectively. The adjuvant must be carefully chosen, taking into account the deposit in the bottle and the product’s aim. Station Oenotechnique De Champagne® offer three main types of adjuvants, bentonite only; combined bentonite and alginate; and bentonite free.  Adjuvants MC and 92 are available in powder or liquid form, offering a choice of a longer shelf-life/less bulk or a ready to use format.


Karen Telford 07464 279475 
www.bevtech.co.uk