Author: Galina Fyodorovna Konopleva
Rusagro Support Technologist
Since the middle of the last century, all developed countries of the world have been working on the creation of butter substitute products technology. Even then, the production volume of this everyday fat product was clearly insufficient to satisfy the rational diet of the entire population.
Industrial production of butter with partial replacement of milk fat with vegetable fat was first mastered in Sweden in 1969.
In the late 1970s, Russian science developed products that contained vegetable fats in addition to butter. The goal of Soviet scientists was to improve the composition of butter and create a new generation product with predetermined consumer and functional properties.
By modifying milk fat with vegetable fats containing a high amount of polyunsaturated fatty acids, with the complete absence of cholesterol, butter with a modified fat phase, close to modern requirements of nutritious food, was created. It had high biological value and dietary properties.
It is important that at the same time the volume of production of such butter from the same amount of milk increased and, consequently, its cost decreased.
In the following years VNIIMS continued researching the nature of non-dairy fats used, requirements to their composition, quality, rational ratio of milk and non-dairy fats in the fat phase of the product, assortment and technological schemes of production. Originally, such products were called “oil with a combined fat phase” or “combination oil”.
And since 2004 another name of this product – “spread” – has been legalized in the Russian Federation, and GOST 52.100-2003 “Spreads and mixtures melted” has been introduced.
The spread is a polydisperse, multiphase system of reverse type water-in-fat with pronounced thixotropic properties.
It is a fat product with a mass fraction of total fat not less than 39%, having a plastic consistency, with a melting point of the fat phase not exceeding 36°C, made from milk fat, cream, butter and from unmodified or modified vegetable oils or milk fat substitutes, with or without the addition of food additives and other food ingredients.
Nowadays, spreads have firmly taken a certain share in the diet of the population.
In 2022, Russian companies produced 137,033 tons of vegetable-cream and vegetable-fat spreads, up 3.1% compared to 2021 results. The compound annual growth rate (CAGR) of vegetable-cream and vegetable-fat spreads for the period 2017-2022 was 2%. The leading federal district of the Russian Federation in the production of vegetable-cream and vegetable-fat spreads is the Central Federal District (42% of production over the period from 2017 to 2022), followed by the Volga Federal District (30.2% of production).
Production of vegetable-cream and vegetable-fat spreads in June 2023 amounted to 9,451.5 tons.
The technology of production of this product and equipment for its obtaining are constantly improving. These are handled by the direct producers of the product, the manufacturers of the HAW, food ingredients, and equipment manufacturers.
According to the current interstate standard “Spreads and mixtures ghee” GOST 34178-2017 there is the following classification of spreads:
vegetable cream spread
: a milk-containing product on an emulsion fat base, in which the mass fraction of total fat is from 39 to 95% and the mass fraction of milk fat in the fat phase is from 50 to 95%.
– vegetable-cream spread:
With a mass fraction of milk fat in the fat phase from 15 to 50%.
– vegetable-fat spread:
The fat phase of which consists of unmodified and/or modified vegetable oils with or without the addition of milk fat (less than 15%).
It should be noted that the first group of products containing up to 50% of vegetable fats when used in the aqueous phase of milk plasma is close to butter in terms of consumer indicators. Whereas the third group may contain no milk fat at all. And with a superficial selection of vegetable fat and other food additives, this spread may represent ordinary margarine.
When replacing milk fat with vegetable fat, it is very important to take into account its organoleptic, physical, structural and mechanical parameters and triglyceride composition. Vegetable fats must be of high quality, safe for consumption and meet specific requirements.
Therefore, a wide application in the production of spreads has been made of DOM – combined substitutes of milk fat, which are balanced compositions of vegetable oils.
RUSAGRO has a wide range of SolPro universal milk fat replacers for spreads, which take into account all the necessary basic characteristics.
Namely: organoleptic indicators, fat storability, chemical composition, fatty acid composition, melting and solidification temperature, triglyceride composition, microbiological indicators, safety indicators, mass fraction of dry matter of food additives used.
Despite the significant difference in the composition of spreads compared to classic butter, the requirements for their consistency and structural and mechanical characteristics remain the same as for butter:
– product consistency at 12±2◦C should be plastic, homogeneous, surface on the cut shiny, dry in appearance;
– the product should hold its shape well at room temperature;
– easy to put on;
– do not lose plasticity during freezing and thawing.
This result can be achieved by observing the general modes of production, taking into account the features of the installed equipment, selection of components and their dosage in the formulation and a number of other nuances.
Let’s consider the technological process of spread production by the HFCS method (conversion of high-fat cream).
Its meaning is that if we want to get a product that is close to butter, we should produce it by the same method.
It includes the following stages conducted in parallel or sequentially:
-Preparation of the fat phase and fat-soluble components;
-Preparation of aqueous (milk) and water-soluble components;
-preparation of high-fat emulsion;
– converting a high-fat mixture into a spread;
– packing, crystallization
Preparation of the fat phase.
Fat components (Solrgo HFC or a mixture of Solrgo HFC and milk fat) are melted in fat melters (fat furnaces) with pipe grates, through which a mixture of hot water and steam passes with temperature control to prevent burning of the product and change of its chemical properties.
In the absence of a grease furnace it is possible to use a container with a heat jacket and an agitator.
The heating temperature of the fats is 55-65°C with a holding time after melting of about 15 minutes.
Surface-active agents (emulsifiers) ensure the production of reverse type emulsion and contribute to the improvement of plasticity of the finished product.
Emulsifiers are pre-dissolved in deodorized vegetable oil or fat base of spread in a ratio of 1 : 5 in a separate container, with constant stirring at a temperature of 5 – 10 ºC above its melting point indicated in the specification.
The control of the correct preparation is the complete transparency of the emulsifier solution. Overheating of the solution is not allowed.
Preparation of the aqueous-milk (aqueous) phase.
Drinking water for product manufacture must have appropriate bacterial purity, taste, color and odor. At best it should be passed through filters for purification and propasteurized.
Used high-fat cream, skim milk, buttermilk should be of high quality with appropriate physico-chemical and microbiological indicators.
Whole milk powder or SOM is reconstituted – the component is dissolved at a temperature of 45°-48 ºC in the ratio with water 1 : 8÷9 with intensive treatment with a dispersant or stirring with a stirrer and pasteurized at a temperature of 85-90°C. The pasteurized reconstituted milk is cooled to emulsification temperature.
Next, the prepared water-soluble formulation components are introduced into the milk phase.
Preparation of high-fat emulsion (fat in water).
In the fat phase with constant stirring emulsifier solution and other fat-soluble components – flavoring (in the production of vegetable-fat and vegetable-cream spread), if necessary, b-carotene in the form of oil solution.
The melted fat phase and the milk phase are mixed by feeding:
1) fat into the aqueous phase
2) lactic phase to fat
The temperature of both parts should be the same or no more than 5ºC difference in the emulsification temperature of the mixture.
To increase the dispersibility of the emulsion, it is treated with a rotary type disperser by circulating the emulsion through it repeatedly. This treatment will reduce the fat globules to a size of 3-7 microns.
Dispersing is carried out at temperature 50÷65ºС, increase of temperature leads to decrease of emulsion stability and appearance of free fat in it, which will further affect the quality of the finished product (decrease of thermal stability and other consistency defects).
And vice versa – the correct selection of the emulsion mechanical processing mode leads to the preservation of the integrity of fat globules, and more liquid fat will be in a bound state.
The resulting high-fat mixture is pasteurized in a pasteurization unit or in a container with a steam jacket at a temperature of 72 – 75 ° C with a holding time of 20 minutes; at a temperature of 85-95 ° C – without holding. After pasteurization, the temperature of the emulsion is lowered to the value of 50-65 ° C and sent to the oil former for thermomechanical processing.
Converting a high-fat mixture into a spread.
Conversion of high-fat mixture into spread is carried out in cylindrical or plate-type oil formers. Depending on the design features of the apparatus, the temperature of the emulsion supplied may be higher than 65ºC. The limit of this parameter, as well as the capacity of the oiler depending on the fat content of the spread, as well as the temperature of the finished product – are specified in the passport of the machine.
Indicators of the correct choice of the mode of operation of the oiler are the consistency and thermal stability of the product and their regulation on the basis of previous developments.
The following conditions must be met for proper operation of the unit:
– fast, uniform and deep cooling of high-fat emulsion;
– constant temperature of high-fat cream and its even flow;
– non-stop operation and a constant level of machine performance;
– technical serviceability of all equipment of the production line (no air inflow, good adherence of knives to the cooling surface of the cylinders);
– good circulation of the coolant in the jackets of the unit.
The process of converting high-fat vegetable cream into spread can be divided into three stages:
– cooling of high-fat emulsion, the stage efficiency indicator is the rate and temperature range of cooling;
– reversal of fat dispersion phases, the efficiency indicator is the degree of destabilization of fat emulsion;
– formation of the primary structure of the product, the efficiency indicator is the intensity of mechanical action.
The degree of completion of the spread structure formation in the oiler is of decisive importance. The criteria of completeness are its consistency, the nature of the structure. If its formation is not completed and is carried over to later stages, the spread will have consistency malformations.
The spread flows out of the oiler in the form of a free-falling jet and has a moving consistency. The most rational way to use filling in bulk into rigid containers when producing by the PVZhS method. In this method mechanical destruction of the product structure is practically absent.
To stabilize the spread and complete hardening it is placed in a refrigerated chamber for a day at a temperature not exceeding +5ºC.
Before packing from monoliths into consumer containers the spread is heated to a temperature not exceeding +16 ºC.