In the considered group includes confectionery obtained by knocking down fruit and berry puree with sugar.
A mixture of applesauce with sugar knocked using egg white or other blowing agents. The intermediate product obtained after churning — the whipped mass — is mixed with a hot, gelatinous agar syrup or with a hot marmalade mass. As a result of the gelling of the mixture, a semi-solid foamy mass is obtained, which, after appropriate processing, is formed into individual candies in the form of bars, spherical products, etc.
According to GOST , there are two types of pastes: glue and choux. In the first case, the mixing of frothy mass with glue syrup (agar-sugar-syrup syrup) is envisaged, in the second case - mixing of the mass produced with apple jelly mass.
At present, our enterprises produce mainly adhesive marshmallow.
Depending on the method of forming the pastille mass, there is a carved marshmallow, produced in the form of rectangular products, and a molding marshmallow (marshmallow), molded by casting (jigging) in the form of products of spherical or oval shape. On the basis of fruit and berry puree create the taste of the corresponding fruits and berries with the help of fruit and berry supplies, essences or essential oils (apple, cranberry, rowan, lemon, strawberry, etc.). Also produce certain varieties of pastilles flavored with vanilla, honey, milk. varieties.
The enterprises of the fruit and vegetable industry of the USSR produce on a small scale a special type of so-called Belevskaya pastille, which is prepared by churning a mixture of applesauce of baked apples, sugar and egg white. It is molded in the form of multi-layered rectangular bars weighing from 0,5 to 4 kg, in the form of rolls.
In some Western countries produce a product called marshmallows, which differs from marshmallow in that it is prepared without the participation of fruit and berry raw materials. Gelatin is used as a gelling agent for marshmallows. The latter is used along with egg white as a frother. In addition to gelatin, sugar, molasses and invert syrup are included in the marshmallow recipe. Marshmallow is molded by casting into starch or it is used for spreading. In the latter case, it is used as a finishing material, replacing cream for cakes, muffins, gingerbread.
Protsess fights (penoobrazovaniya) pastilы
Glue candy is mainly agar jelly, and choux marsh has pectin jelly. However, in either case, pastille jelly is different from marmalade. While the latter is a continuous and homogeneous mass, the pastille jelly has a porous structure with microscopic cells.
(up to 25 μ).
In Pastila jelly distributed small air bubbles, and finished Dried pasta resembles cream solid in structure. These structural features are the result of the fact that in the production process of conventional pastes studneobrazovaniya marmalade combined with the foaming process (churning) apple-sugar mixture.
Fig. 23. Curve of relationship between the size of air cells and the interface.
When churning marshmallow by shaking the apple-sugar mixture for a long time, it foams up, i.e. it is agitated with air; the air is captured by the apple-sugar mass and is fragmented into small particles. As the rate of mechanical agitation increases, the degree of fragmentation of air increases, the size of air bubbles decreases, and the viscosity of the mass increases. A thick foam is gradually formed, composed of small air bubbles, wrapped in a thin film from the surrounding semi-liquid apple-sugar mixture.
In physical and chemical In other words, a foam is a two-phase gas-liquid system. Foams can be considered as concentrated emulsions (which can have not only gas in a dispersed phase, but also a liquid), which are distinguished by a certain structure and high stability. In this case, the dispersed phase is gas - air, and the dispersion medium is a semi-liquid solution of sugar, acid and pectin. This solution forms a shell of dispersed particles of gas (air), which bears on itself the surface boundary layer separating one phase from another.
While there is a strong formation of foam development interface at the boundaries of the gaseous and liquid phases. Increased interfacial formed depends on the size of air cells. The smaller the size of the latter, the greater the surface. The increase of the interface is a certain progression, which is clearly illustrated by the curve in Fig. 23.
In view of the resistance exerted by the force of the surface tension of the liquid (in this case, the apple-sugar mixture), a certain amount of energy must be applied to create a developed interface between the two phases. This can be done in two ways: using mechanical work (knocking down, pulling the mass on (air, saturating the fluid with air through fine-porous partitions, etc.) or by expanding the air under the influence of pressure drop. The more surface development is required, the higher the energy expenditure for this purpose.Some additional energy is also expended on this (overcoming the viscosity of the medium in which the foam is created.
Fig. 24. The scheme of occurrence of surface tension.
Churning is the most common method of introducing air into pastries (candy, / lipstick, whipped fillings, creams, etc.). In / the production of caramel, halva, etc. use for this purpose the method of "pulling" the mass.
For the formation of foam in liquids with strong surface tension, a significant amount of energy is needed. In addition, the pitch obtained in this case does not have the necessary degree of resistance.
The surface tension force occurs at the interface of the liquid due to the difference between the forces of attraction that the molecules of the inner layer and the molecules of the surface layer experience.
In fig. 24 is a diagram of the occurrence of surface tension forces.
While the molecules a inside the liquid experience mutual attraction from all sides, the molecules b from the surface layer (at the boundary between the liquid and the gas in this case) are subjected to unilateral efforts P, which “draw” them into the liquid without meeting a counterbalancing action parties.
Rebinder determines the surface tension of the excess free energy from the surface of the liquid layer of molecules as compared to the inner layers of molecules. The strength of the surface tension and be measured directly and is expressed in ergs / cm2 (Amount of free energy, focusing on 1 cm2 surface layer). The value of this fluid depends on the polarity of its molecules.
The surface tension force always strives to reduce to a minimum the total (the surface of the partition of the entire system, to make it the smallest. In this case, it seeks to reduce to the possible limits the total amount of surfaces of individual droplets that form a foam emulsion. Under the action of this force, individual air bubbles ” merge into one mass. The film of droplets breaks through, individual droplets, gradually merging (aggregating) with each other, form new bubbles-droplets of larger sizes, the degree of dispersion decreases etsya foam "fall off". This process of spontaneous foam breaking emulsions and called coalescence.
In foams, the process of coalescence is very intensive due to the proximity of the droplets relative to each other.
In order to make the foam more stable, to stabilize it, it is necessary to incorporate any surfactant into the film enclosing the air bubbles of the foam.
Surface-active substances, when dissolved in a given fluid, lower the surface tension of that fluid. Substances of this kind have a specific ability to adsorb in excess quantities in the surface layer of the liquid, forming a much higher concentration in this layer than in the rest of the liquid mass. In foam systems (willow emulsions), the dissolved surfactants accumulate mainly in the interfacial boundary layer — in the film on the outer surface of the droplets.
According to modern ideas about the phenomena of the surface layer, the activity of substances of this layer is associated with the action of polar forces between molecules. Molecules of surface active substances are asymmetrically constructed from the polar and non-polar parts. They are located in the surface layer in such a way that the most active polar part of each molecule is directed towards the less polar phase, and the non-polar part toward the more polar phase. The substance is surface-active and is able to adsorb in the boundary layer of two phases, if by its presence in this layer it equalizes the difference of polarities of these phases.
Surface-active substances in relation to water are many organic substances that are soluble in it. Colloid dissolving surfactants cause greater strength of foam systems than molecular solutes. The most typical in this respect are some colloids, for example, gelatin, egg protein, soluble milk protein (lactalbumin), blood protein (serum albumin). They form strong semi-solid adsorption films.
Collecting in the surface layer of the foam bubble film, the adsorbed substance (adsorbent) increases the mechanical strength of this layer, which prevents the bubble film from breaking through and the aggregation of the latter.
Gibbs showed that a decrease in surface tension under the action of surface-active substances in liquid-liquid and liquid-gas systems is directly dependent on their ability to adsorb in this boundary layer and on the concentration of surface-active substance in the adsorption layer.
Action adsorbed surfactants in foams analogous to the conventional emulsifiers in emulsions.
Surface active substances play in foaming processes the role of foam stabilizers, or, as they are called, positive foaming agents, without whose participation it is impossible to produce a durable and stable foam.
As a foaming agent for churning pastila, chicken egg protein is usually used. The predominant component of egg white proteins is ovalbumin (about 50% by weight of all proteins).
In addition to ovalbumin, in the general range of egg white proteins include ovomucin, konalbumin, ovomucoid, ovoglobulin. Conventionally, it is assumed that pricing generally involved the entire complex of proteins because the data on the role of each of the above foaming proteins in eggs is not currently available.
Egg protein is used to churn pastes in fresh, ice cream or dry form. Fresh and frozen protein are equal in their foaming ability.
As for the dried protein obtained by spray drying, the data of Filyukova  show that if the fresh protein is dried at a temperature not higher than 40 — 45 °, then the resulting dry product retains its foaming properties to the full. To protect the spray drying protein from losing its foaming ability during storage, it must be packaged in light-air and moisture-proof containers.
Egg protein is dissolved in the apple-sugar mixture. When shaking a mixture of egg albumen coagulated from solution and is separated from it as a solid coagulate.
The coagulated protein particles are adsorbed in the surface layer, forming a solid film of dispersed air particles.
For replacement of egg white as a foaming agent in the pastille production, bright blood albumin, obtained from “defibrinated serum and freed from red blood balls of the blood of slaughtered animals, is of great interest.
ECNII data show that blood albumin, with proper purification, has high foaming properties, not inferior in this respect to chicken egg protein.
Big interest in this regard is їv lactalbumin recovered from dairy products, or to dissect properly skim milk.
An important indicator for the characteristics of the process of frothers is the rise of mass and its splendor. This property of foam is characterized in practice by the value of the apparent specific weight of the pastille mass.
The role of specific factors in various components and formation of the mass structure Pastila
The quality of the foam mass obtained in the process of churning pastila is determined by a number of physicochemical factors — the concentration of the foaming agent, the amount of dense residue of mashed potatoes and the total concentration of solids in the prescription mixture, the temperature of the mass, the duration and force of shaking the mass when churning, etc. factors of churning pastila and methods of regulating them according to the study of this process, produced by Filyukova et al. .
With an increase in the concentration of solids in a prescription mixture, due to the dense residue of the mixture of applesauce, foaming of the mass, as a rule, improves. It is possible that soluble apple pectin is adsorbed / in the film of air bubbles of whipped mass and contributes to an increase in the strength of this film. Therefore, when working with a highly gelatinous puree and puree with a high content of solids, the process of churning marshmallow proceeds easily and egg protein is little needed.
However, the positive effect of the jelly-forming pectin and other components of the apple puree on churning the pastille mass acts only until the increase in the viscosity of the whipping mass goes beyond the limits at which the viscosity of the mass already begins to delay foaming.
The suitability of applesauce for churning pastes should therefore be assessed mainly for its gelatin-forming ability: “the higher the gelatinous ability of mashed potatoes, the less it is required to take in the sbivi mass.
As for the content of dense puree residue, it is necessary to follow the rule: the higher the gelatinous ability of apple puree, the lower is the optimum dry matter content for it, and vice versa.
When working with a slightly gelatinous puree, adding pectin is very useful to improve foaming. The amount of pectin added should be determined depending on the jelly-forming ability of the apple sauce to be corrected and the pectin preparation itself.
The quality of apple puree, which goes to the production of pastes, can be regulated by mixing apple puree from different batches (weakly and strongly gelatinous) and by adding dry puree to the liquid one.
In the absence of dry applesauce, you can achieve an increase in the amount of dense residue of the gelatinous apple sauce by thickening the latter. So get compacted puree containing 16 — 18% (instead of 10 — 12%) solids.
When working with well-gelatinous applesauce, churning proceeds normally with the moisture of the prescription mixture 41 — 42%. This mixture is obtained by mixing puree and sugar in the ratio 1: 4. Taking the content of dry substances in applesauce equal to 16 — 48%, and in sugar-sand ~ 100%, we obtain a mixture with the content of moisture 41 — 42% by mixing mashed potatoes and sugar in equal quantities. This ratio of applesauce and sugar in the load is at the same time favorable for gelatinization.
Fresh egg white is usually taken in (compounding mix for churning in quantities from 1,0 to 1,5% by weight of the whole mixture. With increasing amounts of protein, there is a gradual increase in weight. However, adding more than 1,5% protein causes excessive thickening of the mass, making it difficult to knock.
Often together with protein (liquid or dry) small amounts of yolk fall into the blend. From practice it is known that the yolk of the egg has a negative effect on the course of foaming in the presence of more than 5% (by weight of protein).
Foaming egg white in its aqueous solutions is somewhat dependent on the pH of the medium. The pH of whipping pastel mass depends mainly on the pH of applesauce. The results of researching the process of churning pastes showed that, under these conditions, changes in the pH of the whipped mixture in the range from 2,5 to 4,0 do not have a noticeable effect on foaming.
With increasing temperature, the quantitative increase of the foam due to the strength of the latter. The resulting foam is thus easily coalesces.
Too low temperature of the mass in the process of churning pastes is undesirable due to the increased viscosity of the mass and the delay in raising it.
In the process of churning pastes, it is necessary to distinguish the initial temperature, which is determined mainly by the temperature of mashed potatoes and sugar at the time of loading. During the churning of the mixture, a gradual increase in temperature occurs due to the mechanical operation of the chucking machine. It was found that the most favorable temperatures for churning pastes are 18 — 20 ° (initial temperature of the mixture) and 30 — 32 ° (final temperature of churning).
Fig. 25. The proposed scheme of combining foamy and gelatinous structure of marshmallow.
The duration of churning to obtain the required lifting and quality of the pastilla mass varies depending on the design of the whipping machine, the speed of rotation of the shaft, the shape of the blades of the agitator and their location, and the size of the load. Optimal working conditions in this regard have not yet been studied.
During the upholstery of the mass, as it is saturated with air, it gradually rises, and at the end of the churning, the initial volume of the prescription mixture is almost doubled. The mass takes the form of a dense fine-meshed (foam, capable of slowly spreading at first, but with a high viscosity.
The resulting mass is amenable to molding immediately after the end of the churning. After some time in peace, it slowly slows down. Gelding occurs in the downed mass not over the entire layer (continuously), as in the marmalade mass, but only in the layer of the film enveloping the air bubbles. The resulting jelly is still fragile, as it consists of air bubbles with intermediate spaces filled with air as well. The specific weight of this mass is about 0,5 (the specific volume is about 2,0). From this, with a known approximation, we can conclude that the mass of jelly is half full of air by air. This mass is difficult to cut, easily separates the liquid phase and sticks. Pastila from it quickly dries and sugared. In order to fix the foamy and gelatinous structure of the downed mass and to give it the properties necessary for further processing, the downed foam mass is mixed with an agar glue or hot marmalade mass. In this way, hardening of the pastille mass is achieved.
The mechanism of combining gelatinous and foamy structures when mixing the mass with glue (or marmalade) mass can be represented as follows: when mixed with cold mass, the hot mass of agar glue or marmalade fills the air spaces between the bubbles of the mass, displacing air out from there (Fig. 25). In this case, the strength of the film of the structural elements of the mass increases significantly. The temperature of the entire mass rises to 50 °. The strength of the film increases due to the fact that the adsorbed albumin gel of the film at a specified temperature, close to the coagulation of albumin, is fixed in it in the form of a dense coagulate. At the same time, as the mass cools in the space between the bubbles, durable agar (or pectin) jelly is formed. Mixing the downed mass with a hot jelly (or marmalade) mass thus creates the necessary conditions for the formation of the structure of marshmallow.
After the mass cools, a characteristic table jelly is obtained, which differs from marmalade jelly in a finely porous structure, due to the smallest air inclusions, evenly distributed in its mass.
Construction of recipes Pastila products
Agar for gum mating is used in air-dry form (with a water content of 15 — 28%) or in the form of 1% water jelly. The amount of agar used for the production of gummed pasti is from 0,3 to 0,6% (in terms of air-dry agar) to the weight of the finished product, depending on the gelatinous ability of the agar and the variety of prepared pastes.
Molasses is introduced into the formulation of marshmallows in the amount of 10 — 15% by weight of sugar. Replacing a part of the sugar in the pastille, molasses helps to reduce the degree of supersaturation of the pastille mass with sucrose and thus makes it possible to eliminate or slow down the saccharification of the marshmallow. Molasses dextrins contribute to the thickening of the pastille mass, but an increased addition of molasses is undesirable because; it can worsen the consistency of pastes, contributing to the tightening of the latter and complicate the drying process.
To create the taste of certain fruits and berries, natural fruit and berry purees or supplies, essential oils and the corresponding fruit and berry essences are introduced into the recipe. Let out varieties of pastilles, flavored with honey, dairy products (honey, cream, etc.) in accordance with the approved recipes.
Sometimes acid is added to the marshmallow in order to bring its content in the finished product to the norm established by the standard.