Shortbreadpiping pastry. Piping pastry is a pastry with such a low material coherence so that it can be piped on a baking sheet. The pastry consists of an emulsion, the continual phase is the fat phase.
salt and 0,2 kg sodium hydrogen carbonate.
The flour that is used is patent flour. This is flour that is made from the center portion of the endosperm. The protein quality does not have to be perfect because a gluten network is not to be desired in this kind of pastry.
The fat needs to be a soft fat. The material coherence of the fat needs to be low because all the ingredients are to be mixed with this fat.
Sodium hydrogen carbonate is the rising agent. During the baking process it is converted into carbon dioxide under the influence of heat. This makes the end product even more light.
water is mixed with the fat. It is necessary to stir powerfully in order to get an emulsion. The obtained emulsion is a water-in-oil emulsion. This means that drops of oil are spread through the oil.
sugar is mixed with the emulsion. After that the flour, the salt and the rising agent are mixed with it.
Because the emulsion has a lot of fat and only a little water, the stiffening of the starch is limited. This causes less cohesion in the product, which results in a crisp cookie. The rising agent is added to make the product even more crisp.
While mixing, air should be beaten in it which adds to the crispiness.
The protein of the flour makes sure that there is cohesion in the pastry. But the protein does not form a gluten network because the emulsion is a water-in-oil emulsion, which has not enough water available.
pressure (above the yield stress) it is liquid, with low pressure it is not. Due to this it is possible to pipe the pastry under high pressure. The pastry is piped on plates or strip steel. After piping the pastry, the proteins of the flour restrict the pastry from spreading out so that the ridged texture of the nozzle remains.
temperature of 180ºC for 20 minutes. After baking the cookie it has a golden yellow colour. This colouring is due to the Maillard reactions, a reaction at high temperatures between reducing sugars and proteins. Beside the brown colour the Maillard reaction also forms the aromas.