The shelf-life of the cake is mainly determined by the following factors: (1) type and quality of the raw materials used (mainly the fat types and quality), (2) baking conditions, (3) sanitary conditions, (4) packaging, (5) storage conditions, (6) amount of added sorbate (in some countries the allowed amount is lower than the 0.2% of the EU/US), (7) modifications in the recommended cake recipes (if done). Generally, while the conditions are optimal, the shelf-life of most of the final cake ranges between 3-6 months, while in some cases the shelf life is even more than one year. On the other hand, in improper conditions (mostly - insufficient baking or poor hygienic conditions) the shelf life may be even less than one month. Thus, every cake factory has to determine the shelf-life of the cakes by itself, according to its own conditions and criterions of shelf-life. As a policy, we do not officially give any guarantee for the final cakes shelf life.
We consider the baking conditions as the most important issue during the cake development trials and during the mass commercial cake production.
Sometimes, while carrying out trials with the PentaCake, the operator sets the oven temperature to a certain temperature (e.g., 170°C) and the oven screen apparently shows that indeed this is the temperature inside the oven. Frequently, the set temperature and the temperature shown on the oven screen are completely different from the real temperature measured inside the oven.
Thus, we strongly recommend measuring the real interior temperature by an independent analog oven-resistant thermometer. If the temperature is lower (e.g., 140°C-150°C), and the baking time is not elongated accordingly, the cake will be too humid. During the cake storage, the water would migrate from the interior of the cake to its surface, which would develop a "pudding texture" after a while. Then, there are chances that mold would shortly appear.
On the contrary, while baking in too high temperatures, the cake apparently looks ready and well browned after a short baking time, and then taken out from the oven. However, the interior remains wet, and, again, the above mentioned phenomenon may occur. Accordingly, in every trial with the PentaCake, it is recommended to bake a few cakes in different baking times.
In the recommended cake recipes for the implementation of the PentaCake, we recommend the usage of sorbate as a preservative.
The default values in the cake recipes are 0.18% Sorbic acid or 0.24% potassium sorbate, which were calculated according to a limitation of 2000 ppm sorbates in the final baked product.
In some countries, the maximum sorbate limit is smaller. Then, there is need to compensate this lack of preservative by other means. The sorbate is mostly active in acidic conditions. Thus, while its concentration is low, there is need to increase its effectiveness by increasing the acidity of the cake (i.e., reducing its pH). This can be done by the addition of acetic acid. Additionally, elongation of the baking time reduces the water activity of the cake and improves its microbial stability.
Fresh egg might be substituted by egg powder. 100 parts of egg can be replaced by 75 parts water and 25 parts egg powder. The resulted cakes might be slightly inferior in terms of volume or texture. There might be also a slight off-flavor of the egg powder.
The laboratory experiments shall imitate the real conditions of industrial baking - generally, tunnel oven, "Auto-Bake" oven or convection rack oven. Therefore, the experimental baking can be even done in a small turbo oven. While making the baking experiments, there is need to care for the following: