Week 15-  The Art of Moulding

​

O for Oxidation

​

The first chocolate moulds appeared around 1830 in France. At this time chocolate was ground into a paste and shaped into bars, logs or blocks, then grated in hot milk to make hot chocolate. The moulds were made of wood or clay but didn't give a shiny surface to the chocolate;  

 

by 1840, silver and pewter started to be used instead, then copper and coated tinplate.   But because of oxidation, and the difficulties of working with them, these metals were soon replaced in the 20th c by bakelite (plastic resin) and stainless steel moulds, which don’t oxidate or stick to the chocolate as much.

 

Oxidation occurs in all metals, except in precious ones, when exposed to air and humidity. The metal becomes loose, so in the long run the moulds become unusable and dangerous to peoples' health.

 

Oxidation also occurs in chocolate, it’s called the Bloom;

 

Sugar bloom happens when chocolate is exposed to humidity, like coming out of the fridge on a hot day, producing surface moisture because of the differences in temperature, which causes the sugar in the chocolate to dissolve and remain as crystals on the surface when the water has evaporated; it makes the chocolate look white/grey in colour, and sticky; it is still safe to eat just not very appetizing;

 

Air and light also oxidate chocolate, turning it rancid. The cocoa butter fat disintegrates, the flavours change and it can develop an unpleasant smell; white chocolate is especially sensitive because it doesn’t contain anti-oxidants, contrary to milk and dark chocolate which do, therefore slowing down the oxidation process.

 

From the 19th century on we see moulds being perfected in different materials. Most recently polycarbonates (solid plastic) dominated the whole industry by being very robust, safe to use and giving the surface of the chocolate a lovely shine.

 

Another method involved making shapes out of plaster or wood, and glueing them at regular intervals to a wood stick, then handling the stick on both ends,  pressing the shapes into wet cornstarch, then letting it dry; The dried prints would be covered with cocoa powder, before filling them up with melted, tempered chocolate, so the starch wouldn’t stick to the chocolate when setting.

 

Moulds were initially made to celebrate specific occasions, such as Easter with egg, bunny and hen shapes; Valentine’s day with heart shapes; Christmas with Santa, christmas tree, star shapes... They are still made today in many forms and for many more occasions.They are also called "moules bijoux" (jewel moulds), masterpieces created by goldsmiths;

 

Fry & Sons produced the first moulded Easter egg in the UK, followed in 1875 by Cadbury and in 1904 by Rowntree.