The percentage composition of ice cream can be determined, taking into account the following factors:
– Legal requirements regarding the fat content, total dry matter;
– Consumer preferences regarding the degree of sweetness of the ice cream, its creaminess, etc.
– The quality / price ratio, with reference mainly to the competition products;
– Other conditions that refer to the availability of the raw material, the work equipment from the factory endowment, etc.
Determining the content of carbohydrates (sugars) and their importance . Sugars and sweeteners are used in ice cream due to the fact that it lowers the freezing point of the mix and ensures the degree of sweetness of the ice cream, a degree of sweetness that potentiates and its flavor. Another role of sugars in the ice cream mix is that it participates in the formation of the body of the ice cream, by adding total dry matter.
Freezing point depression factor (FPDF). The effect of lowering the freezing point caused by sugars and other sweeteners used in the recipe, compared to sucrose (sugar) is called the Freezing Point Depression Factor (FPDF). Sucrose (sugar) has this factor equal to 1.
The freezing point of an ice cream mix is initially dependent on the amount of solids dissolved in the liquid. The more solids dissolved in the liquid phase, the lower the freezing point of the mix.
Using various types of sugars (carbohydrates) in the recipe of an ice cream mix can lower the freezing point as well. Due to the fact that the number of molecules per gram of carbohydrate depends on the molecular weight of that carbohydrate, a carbohydrate with a low molecular weight will cause a greater decrease in freezing point than a carbohydrate with a high molecular weight.
The non-fatty dry matter of dairy origin (SUN), used in the manufacture of the mix, also determines the decrease of the freezing point. For the faster calculation of the FPDF factor of an ice cream mix we consider that the dry matter of the dairy components used is constant. This determines that the influence of the dairy components on the freezing factor (depression) of the freezing point is constant. That is why we can eliminate the components of dairy origin from the calculation when calculating the FDPF of an ice cream mix.
To calculate this factor corresponding to an ice cream mix, multiply the FDPF value corresponding to each type of carbohydrate by the percentage value that occurs in the recipe of this type of carbohydrate.
Determining the degree of sweetness of ice cream. The use of various types of carbohydrates (sugars) will cause various levels of sweetness important to be considered as an effect in the composition of the mix. Because sucrose (sugar) was chosen as a reference for the freezing point depression factor, it is also chosen as a reference in the calculation of the degree of sweetness, its value for sucrose being also 1.
The relative degree of sweetness and the FDPF factor for various carbohydrates are usually used to obtain ice cream are shown in the table below.
When calculating the sugar (carbohydrate) composition of an ice cream mix, both the relative sweetness and the freezing point decrease factor must be taken into account, as the sweetness is determined by the consumer’s preferences and the FPDF factor determines the type. of ice cream that can be made.
A soft ice cream that can be easily taken in a teaspoon is different from a water-based ice cream and therefore will need to have a higher FPDF. Thus, if by calculating the composition of the mix a factor of decrease of the freezing point between 14-20 is obtained, then the ice cream will be of hard texture and will not be easy to take in the teaspoon. This factor of depression is characteristic of an ice cream that can be extruded, made on a stick or water-based. For a soft ice cream that can be easily taken in a teaspoon, the freezing point decrease factor (FPDF) should be between 20-25. This factor of depression is characteristic of artisanal or glass ice cream.
To calculate the sweetness of an ice cream mix, multiply the relative sweetness of the sugars (carbohydrates) used in the mix by their percentage value in the recipe and determine their amount.
Below are 2 examples in which the FPDF factor is modified without being modified but also the relative degree of sweetness of an ice cream mix. Recipe 1 is designed to obtain a hard ice cream, which can be produced on a stick or can be extruded. If the ice cream is to be made in a glass to be consumed with a teaspoon, then the FPDF factor must be modified by varying the type of carbohydrates in the recipe. If the taste must remain the same, then the degree of relative sweetness must not be changed. Recipes 1a and 1b illustrate that the FPDF factor can be increased without changing the degree of relative sweetness or the total dry matter content of the ice cream. In Recipe 1a, dextrose is used instead of glucose syrup