Why does couverture / chocolate need to be tempered?

Name: Why does couverture / chocolate need to be tempered?
Cuisine: Switzerland

Why does couverture need to be tempered?

The beautiful sheen on products made from couverture is of the utmost importance and gives the end product its appetising appearance. The finished products only achieve this sheen if the couverture or chocolate has been tempered correctly. The complex cocoa butter is responsible for the appearance and, consequently, for the sheen. It is polymorphic and contains various fatty acid groups (stearic, palmitic and oleic acids) with different melting points ranging from 20 ºC to 47 ºC.

These different fats have the property of solidifying into unstable and stable crystal forms as they cool. The fat components contained in cocoa butter therefore consist of both ‘stable’ and ‘unstable’ fat crystals. As all couverture chocolates contain cocoa butter, it is essential to temper it in order to prevent any adverse effects on the consistency or appearance. Tempering couverture chocolate involves processing the fat components of the cocoa butter in such a way that it can be moulded more easily and, after processing (whether into bars, pralines or hollow figures), achieves the desired sheen and snap. For those with little experience, tempering works best using the seeding method, in which two-thirds of the couverture is melted and then ‘seeded’ with one-third of fresh couverture drops. This process creates the perfect balance between stable and unstable fat crystals. You can find out moreHERE.

If you do not do this, the couverture may stick to the praline, bar or figurine moulds or take on a greyish appearance. Whilst this may not look particularly appealing, it does not affect the taste.

So one could say that if chocolate – or couverture – did not contain any cocoa butter, this would, of course, simplify things considerably, as the couverture would not need to be tempered. This is precisely what has been achieved with cake glaze (also known as fat glaze or cake melts). Cake glaze is a chocolate-like mixture that does not need to be tempered, yet still has a glossy finish. In cake glaze, the complex cocoa butter is replaced by coconut, palm or other vegetable fats. These fats ensure good flow properties and a lovely sheen in the end product. Cake glaze saves a lot of time, as tempering itself does take a fair bit of time. The downside of cake glaze, however, is that it does not come close to chocolate or couverture in terms of flavour. Cake glaze should therefore never be used for high-quality confectionery products such as pralines or chocolate bars. The fat-based glaze is only suitable for coating tarts, cakes and confectionery, or for decorating small pastries and biscuits.

Storage & Shelf life

As a general rule, chocolate, couverture and cake glaze should always be stored in a dark, cool and dry place.

The shelf life varies depending on the type. As a rule, white chocolate | couverture has the shortest shelf life at 6 months, followed by milk chocolate at 1 to 1½ years, and dark chocolate at up to 2 years.