The White Lady - Part 1
Meringue and its secrets in the new blog by Enrico Gumirato!
Friends of ERRE4M welcome to this new post. Today we are going to talk about meringues!
After having dealt with sponge cake as a whole, in this post we are going to dwell on the use of the whipping power of eggs; in this case more precisely on the very high whipping capacity of egg whites or egg whites.
Before delving into the composition and methods of preparation of meringues, I would like to dwell on the main characteristics of the basic ingredient of this cake, that is egg whites.
The egg white is mainly made up of ovalbumin, a protein which is decisive for the whipping properties of the egg white.
TECHNICAL EXPLANATION ON OVOALBUMIN
Ovalbumin is a glycoprotein, that is a double molecule: one is formed by a protein and the other by a sugar; this property makes it extremely capable of binding and trapping air. This is one of the reasons that allows the egg white, after beating, to increase its initial volume fivefold.
A second reason that gives egg white a very high foaming power is given by its composition; it is essentially made up of water 86% and proteins 13%; this characteristic of not containing fat inside (as in the case of whole eggs and even more so of yolks) allows the egg albumin to easily bind together thanks to the energy produced by the movement of the beater.
TECHNICAL EXPLANATION ON THE ALBUME
When the egg white undergoes a mechanical movement it absorbs air, thus dispersing a gaseous phase into a liquid phase and forming a real foam; it happens that in the egg white (as said without fats) the air can easily interrupt the forces that bind the surface molecules together, mixing intimately in the formation of a foam that is very stable. In yolks and whole eggs, on the other hand, the presence of fat prevents the superficial forces from being released, so that the amount of air that manages to enter is smaller in quantity and more easily dispersed. Hence the greater stability of whipped egg white compared to yolk or whole egg.
Now let's take a look at some tricks that facilitate and improve the foaming characteristics of egg whites and that are valid for any foaming use of egg whites.
ADDITION OF ACIDS: citrus fruit juice, white wine vinegar, cream of tartar added in small quantities increase the whipping power because the raising of the PH of the egg whites allows the proteins to come closer and consequently a greater absorption of air.
HEATING: for about three minutes at 50 °C leads to a considerable improvement in the whipping time and volume.
SALT: contrary to what is often heard, the salt in the egg white only marginally influences its whipping power; on the contrary, as the whipping continues, it would tend to depress its protein functions.
OIL AND FATS: as mentioned above, the whipping power of egg whites decreases drastically in the presence or with the addition of oil or fats; even just a small amount of oil in the egg whites causes the foam to collapse in an evident way, therefore the presence of yolk in the egg whites or fat in the equipment used delays and slows down and in significant amounts inhibits the whipping power.
MILK AND DAIRY PRODUCTS: the addition of milk fat, butter, cream strongly inhibit the stability of the egg white foam.
WATER: the addition of water in the egg white increases on one hand its volume but on the other hand it decreases its stability.
We also know that the egg white foam maintains its aerated structure for a long time even with the addition of a certain quantity of heavier ingredients such as sugars. In fact, sugars are the ingredient commonly used with egg whites to form meringues, although, as we will see in later posts, other ingredients can be added to the whipped egg whites and sugar to create "modified meringues".
White beet caster sugar is normally the most commonly used because of its characteristic fine grain size that allows it to dissolve easily in the egg whites and gives stability to the mass; it must always be free of impurities and any trace of other raw materials so as not to weaken the egg whites. Icing sugar can also be used even though it is generally added with starches that do not affect the whipping process and on the contrary tend to keep the shape stable during cooking.
As meringue is prepared only with egg whites and sugar, it is immediately clear that the variations in the ratios between the ingredients are very limited while the processing methods applied vary according to the final product we want to obtain.
The ratio of egg whites and sugar does not determine the sweetness of the product so much as its consistency and meringue is usually divided into two mixtures: LIGHT and HEAVY. The light meringue normally has a proportion of equal weight of egg white and sugar while the heavy meringue will see double the amount of sugar compared to the egg white. (LIGHT MERINGA 100g egg whites + 100g sugar; HEAVY MERINGA 100g egg whites + 200g sugar).
In any case, it can be said that the two types of meringues, including all the possible intermediate variations in the ratios between the two ingredients, do not express a higher quality of one over the other:
LOW SUGAR QUANTITY = light meringue, consistent, rigid, resistant and firm
HIGH SUGAR QUANTITY = heavy meringue, tender and soft consistency, less solid.
The procedures for preparing meringue are many, but are normally distinguished into 3 types: COLD METHOD, HOT METHOD, ITALIAN METHOD.
Let's analyze now the first two that concern baking meringues.
Metodo a freddo
100 egg whites at room temperature
100/200 g caster sugar
Aroma to taste
- Start by mixing by hand in the bowl where you will assemble the meringue the egg white with about 1/3 of the sugar making sure that the latter begins to dissolve;
This operation gives rise to two events namely: the egg white will not over-assemble thus avoiding generating the classic lumpy structure of the egg white when it is too whipped and also by adding solid (sugar) to the egg white, you will get a more consistent whipped, rigid and with a greater volume during cooking.
- After having well mixed the egg white with the first part of sugar, start to whip everything in second speed and when on the snow will begin to form the signs of the whip will pass in third speed until you get a frothy and firm whip. At this point you will bring the whisk in the first speed adding the second third of sugar a little 'at a time,
- remove the bowl from the planetary and add the last third of sugar stirring gently by hand with the help of a pot licker.
- to finish you can add any flavor and coloring.
Metodo a caldo
100 g egg whites at room temperature
100/200 g caster sugar
Aroma to taste
- In principle, proceed as for the cold method except that the egg white must be heated to 50 °C in a bain-marie with half the amount of sugar maintaining the heating temperature for three minutes;
- whisk everything in third until it cools;
- remove the bowl from the planetary mixer and mix in the second half of sugar by hand using a pan licker, adding aroma and/or coloring at the end.
- when the process has finished, normally pour the meringue into a pastry bag with a smooth or star-shaped nozzle and work into the desired shapes on baking paper.
We conclude this post on meringues by looking at their cooking. More than real cooking for meringues we talk about drying; in fact this step is done at low temperature and for a long time. The temperature of large professional ovens is set around 90-110°C for a duration of 2-3 hours always with the steam suction system in the cooking chamber activated (the technical term is VALVE). The low heat of the oven has two functions:
- the first is to allow a slow evaporation of the water in the egg white and the controlled crystallization of the sugar which will then allow a slight leavening of the meringue and the creation of an extremely dry, crumbly, light product with a crystalline structure;
- the second is to prevent the meringue from taking on too much of an amber color which would happen at temperatures above 120°C; the low baking temperature instead allows the meringue to maintain a snow-white appearance as after whipping and consequently also a very pleasant appearance.
In home ovens I suggest to keep the cooking time unchanged but to lower the temperature to 50-60°C because the small size of the oven tends to create more heat inside the cooking chamber. Baking at 90-110°C we risk ending up with meringues with a hazelnut colour, which is not very satisfactory. In order to simulate the "VALVE" of professional ovens it is sufficient to create a slit on the oven door using the blade of a knife so that the steam generated during cooking escapes from the oven, drying the product perfectly.
(Blog by Enrico Gumirato, Pastry Chef and Trainer)