Pectin is an integral part of fruits, berries, vegetables, stalks of leaves, roots and other parts of plants. The fruit and berry raw materials used in the confectionery industry contain pectin, on which the basic technological properties of this raw material (the ability to gelatinize) and the quality of finished products (resistance to sugaring and wetting) depend.
In addition to the pectin used in the native form, i.e., pectin, found in the plant tissue of fruit and berry raw materials and semi-finished products, preparations of pectin extracted from one or another pectin-containing raw material have recently become widely spread.
Food pectin, manufactured in dry and liquid form, is used as a gelling agent in the manufacture of jelly-like fruit and berry products (jellies, jams, marmalades, fruit candies).
For the industrial production of pectin, waste from the processing of apples (apple pomace obtained as waste from the production of juice and wine) and citrus fruits (crusted oranges, lemons and grapefruits) are commonly used.
In Ukraine, for the first time, the production of pectin from a new type of plant waste — from threshed baskets (“caps”) of sunflower — was organized.
In Ukraine, a technological scheme for the production of high-quality jelly-forming pectin from beet pulp has been developed and put into practice.
Pectin content in various types of raw materials as follows:
|Type of raw materials||Soderzhanie pectin in%|
|Dry citrus crust:|
|Dry beet pulp||25-40|
|Air-dry sunflower basket||18-23|
|Dried apple pomace||to 18|
Pectin is a mixture of carbohydrate substances that are produced in plants as a result of the breakdown of cellulose and hemicellulose. The pectin complex is based on a polygalacturonic nucleus consisting of many galacturonic acid residues interconnected in the open chain of the main valences of the pectin molecule.
The carboxyl groups of galacturonic acid residues are saturated to some extent with the radicals of methyl alcohol CH30.
Pectin polygalacturonic chain is represented as follows:
Each chain link is a six-membered ring of five carbon atoms and one oxygen atom.
The number of links in the chain in the molecule of pectin reaches 1000.
Galactose, arabinose and Araban are involved in the composition of the pectin molecule as accompanying substances.
The molecular weight of pectin varies between 25 000 — 100 000.
The amount of the molecular weight of the pectin is a measure of its ability to studneobrazovaniyu.
Pectin swells easily, it is dissolved in cold and hot water.
Aqueous solutions have high viscosity pectin.
Alcohol, acetone, salts of polyvalent metals precipitate pectin from its solutions.
When cooking pectin with sugar and water (the concentration of sugar should be 60 — 70%), it forms strong jelly.
The frost point temperature of the pectin-sugar solution varies between 65 — 75 ° and depends on the individual characteristics of pectin.
Acid is added to accelerate the gel formation of pectin and increase the strength of the jelly.
The pH optimum for gem formation of pectin is within 3,2 + 0,2.
The above data and conditions of gelation are related to the so-called normal, that is, methoxylated pectin (with a content of methoxy groups not lower than 7%). However, industrial production of the so-called low-methylated pectins has recently been created (with the content of methyl ether groups below 6%).
The peculiarity of low-methylated pectins is that they are capable of forming jellies with a small amount of sugar (about 35% sugar by weight of jelly) or jellies with ions of polyvalent metals without sugar, the so-called ion-bound jellies. These varieties of pectin are used to make sweet jellies with a minimum content of sugar or jellies that do not contain sugar and are intended for salads, mayonnaise, etc.
Pectin differs from agar by increased sensitivity to heat, especially at temperatures above 70 °. An increase in the temperature and duration of heating a mixture containing pectin leads to a weakening of the jelly-forming ability of pectin.
Pectin is more resistant (compared with agar and agaroid) with respect to acid. This is essential for the production of fruit and berry products, mostly in an acidic environment.
Requirements for the quality of powdered pectin from sunflower baskets regulated VTU 382 MPPT USSR.
VTU provides for the color of the powder from grayish-white to yellowish, the taste is slightly sour in the absence of foreign taste and odor.
|Normal powder moisture%||no more 14|
|Common ash in%||no more 3,5|
|The content of pectin for pectates in%||however 68|
|Number% methoxyl groups||however 6,0|
|pH 1% tion of pectin solution||3,2-3,5|
Ability to studneobrazovaniyu evaluated in a special unit effort (required to break a standard cake jelly> 225 g / sm2.
The dosage of pectin powder for molded jelly marmalade is 1,25 — 1,5% by weight of the finished product.
Powdered pectin packed in tin cans, made of durable cardboard or paper casting a net weight up to 4,5 kg.
Transportation and storage of pectin should be carried out at a relative humidity of no more than 85% and at a temperature not higher than 30 °.
Shelf life 6 months.
Agaroid ("Black Sea Agar")
Agaroid is a gelling agent, similar in its physicochemical properties to agar and in some respects to pectin.
Agaroid is obtained from the purple algae of the genus Philofora, extensive thickets of which are found in the northwestern part of the Black Sea, in the triangle Sevastopol — Odessa — Akkerman.
On the basis of these algae, large-scale agaroid production was created in Odessa.
Technological processes for the production of agaroid from fillora are developed for the first time in Ukraine.
The chemical composition and structure of the agaroid are still insufficiently studied. According to Kobzarenko, the agaroid contains galactose, glucose and fructose, sulfur, Ea, Ca, M £, a small amount of acetyl groups. It is slightly soluble in cold water and good in hot.
Aqueous solutions (sols) of agaroid after cooling down form gel (gels), starting with the concentration 0,8 — 1,0%.
Under the conditions of confectionery production, the capacity for the formation of agaroid is less than 3 times less than that of agar, and 2 — 2,5 is times less than that of pectin. To obtain agaroid-sugar jelly (with a concentration of sugar 70%) you need about 3% agaroid to the weight of the finished jelly.
Melting point of agaroid-sugar-water jelly (3% agaroid, 67% sugar, 30% water) 40 — 45 °.
The frost temperature in the presence of acid is close to the pectin jelly temperature, i.e., to 70 °.
An agaroid is similar to pectin in its sensitivity to heat and agar in relation to increased sensitivity to acid.
Hydrophilic properties (ability to retain water) are less pronounced in agaroid than in agar and pectin, as a result of which its resistance to drying and sugaring is lower than that of agar and pectin.
Agaroid roller drying is produced in the form of films, and also in the form of rings cut dried in air.
Gelatin - gelling agent. animal origin, the beginning of which is, gluten. The latter is a complex protein compound resulting from the thermal hydrolysis of collagen, or ossein, which is found in the skins, tendons, cartilage and bones of land animals.
The empirical formula of collagen (ossein)
by the hydrolysis of its merger with one molecule of H20 is obtained gluten:
Gelatin is insoluble in ether, chloroform, benzene, absolute alcohol and in other organic solvents.
When heated, gelatin softens, swells and chars, giving off the smell of burning horns.
In cold water and in dilute acids, gelatin swells, absorbs at room temperature 10 — 15 -fold amount of water, turning gradually into a jelly.
Gelatin is easily soluble in hot water. When the hot solution cools, it stirs (to form a weak jelly you need at least 1% gelatin).
The aqueous gelatin gel is melted when heated to a certain temperature, the gelatinous structure is restored again when cooled again.
Gelatinous gelatin is very sensitive to temperature: when heated above 60 °, gelatin's ability to gel is weakened, and when heated with acids and alkalis, it loses this ability.
According to current standards distinguish gelatin food, technical and photographic.
Gelatin comes in the form of transparent sheets or plates, powder or grit.
Food gelatin should give colorless (to light yellow) solutions. Its humidity is not higher than 16%, ash content is not higher than 2%.
The foaming properties of gelatin.
The strength of 10% gel in degrees with a special device not lower than 500.
Microbiological resistance of 5% solution is characterized by persistence of at least 7 days.
In terms of its ability to gelatinize in confectionery production, gelatin is weaker than 5 — 8 times agar and pectin. Gelatin-sugar jellies are highly sensitive to the action of acids.
In the food industry, gelatin is used for making sweet jelly and pouring, for fish and meat dishes and canned food, ice cream, for clarifying wine, beer, etc.
On confectioneries USSR gelatin, agar previously used as a substitute in the production of marshmallow.
In the practice of confectionery production abroad gelatin is used as an anti-crystallizer in the manufacture of fondant candies and as a structurant for special products called marshmallows, which are similar in structure to our marshmallow.
Algina is a short designation for alginic acid preparations obtained from brown algae of the species kelp digitite, kelp hyperborea and the Fuchsian genus.
Alginic acid, obtained by processing these algae, is a product of the polymerization of mannuronic acid, consisting of the anhydride residues of mannuronic acid C5Н704 SOON.
By Yevtushenko alginic acid is an equilibrium mixture of polymannuronic acid and polyanhydride.
Currently, a number of options for industrial production method of alginic acid and its preparations.
Alginic acid and its salts, with the exception of alkali metal salts and magnesium, it is difficult to dissolve in water.
Cold water soluble alginic acid compound in a concentration-dependent form viscous solutions or jellies.
Strong acids (NS1 or H2SO4) Alginic acid is precipitated from its aqueous solutions in the form of a continuous gel or precipitate of the fibrous structure.
In alcohol solutions with an alcohol concentration above 50%, in chloroform, glycerol, ether and in other organic solvents, alginic acid is practically insoluble.
The strong bases of potassium and sodium and their salts have a depolymerizing effect on algin. The latter is also very sensitive to the action of an acidic environment with pH <5,5.
alginic acid drugs marketed in the form of alkali metal alginates, often in the form of NH4 salt. They have recently received wide distribution in various sectors of the food industry as a stabilizer or emulsifier, in particular in the production of ice cream, mayonnaise, in the dairy industry, etc.
Greater sensitivity to alginates to acid (pH of the medium should be at least 6,0) and heating limits their use in the confectionery industry.
In the production of confectionery, alginates can be used only when it is not necessary to prepare strong jellies that can be cut with a knife, i.e., only to obtain weak jellies, creams that are not subjected to strong heating during the production process. In some cases, alginates can be used as anti-crystallizers.
Alginate preparations are made in the form of a powder with a moisture content of about 20%. Their quality is controlled by viscosity 1% solution.
The ability to gelatinize powder degrades during storage. Neutral preparations or slightly acidic are more stable during storage than preparations having a weak alkaline reaction.
Insoluble salts, such as dry calcium alginate, have good storage stability.
Extract carrageenan (Irish moss extract)
Carrageen extract is a gelling agent derived from the scarlet algae of the species Chondrus crispus (so-called Irish moss), growing on the shores of the Atlantic Ocean (in England, Ireland, France, USA).
The active gelatinous principle of carrageen extract is carrageenan, which is a sulfate ester of a polysaccharide consisting of galactose residues, i.e., it is similar in composition to agar.
Studneoobrazovateli from the Irish moss in recent times are spreading in the United States, France, England.
Dry extract (moisture 5 — 6%) is soluble in water when heated. According to reports, its ability to jelly formation is close to that of agar and pectin. It is used as a stabilizer for milk (adding it in the amount of 0,04% to milk at 70 ° ensures the formation of a strong suspension with casein).
0,5% dry carragen extract is given with milk, durable jelly, which is used as a basis for milk puddings and other products.
There are instructions on the use of carrageen extract in the confectionery industry as a gelling agent for the so-called pipe jelly, toppings, marshmallow, as a stabilizer in the production of chocolate milk, biscuit creams and ice cream.
In addition to the gelling agents, a number of hydrophilic colloids are used in the confectionery industry, which in certain respects approach the group of substances in question. First of all, this includes the modified (modified) starch, as well as the so-called gums (gums) - vegetable water-soluble glues of carbohydrate character. It is necessary to indicate from the latter: tragant, gum arabic, cherry gum glue, etc.
These products are different from typical gelling agents in that they (do not have the ability to form strong gelatinous structures without strong boiling of prescription mixtures.
Modified (Modified) Starch, prepared according to the scheme VNII, obtained from ordinary (native) starch by weak acid or enzymatic hydrolysis. Modified starch differs from ordinary ability to form a paste with a lower viscosity compared with this ability in ordinary starch paste, so it is convenient to use it in confectionery production conditions (for cutting, pouring). With the introduction of modified starch (moisture content up to 10%) in the prescription mixture, it is possible to obtain candies such as tin jelly marmalade. The amount of injected starch is about 10% by weight of finished products. Candy of this type should be molded into soft forms (starch or sugar). In addition, the usual starch is used for the preparation of products such as Turkish Delight and others.
Gum (gum) - resinous substances released from plants in the form of amorphous masses capable of hardening in air. By their chemical nature, these substances occupy an intermediate place between hemicelluloses and pectin substances. The bulk of these substances are carbohydrates (hexoses and pentoses), galactose, arabinose, xylose and other uronic acids (predominantly galacturonic).
The confectionery industry of Ukraine used the following gums: tragacanth, acacia, cherry gum adhesive.
Tragant is collected from the branches of shrubby plants of the Astragalus species growing in the countries of Asia Minor (Syria, Lebanon, etc.). The liquid mass protruding on the surface of the bark of the plant hardens for several days to the state of a stratum corneum, at the same time taking one or another random shape with a changing color from light yellow to brown.
During hydrolysis gives pentoses and methyl pectose. Slowly dissolves in water, to accelerate the dissolution of powdered tragant moistened with alcohol and pour water in relation to 1: 75, 1: 100.
Gum arabic (acacia) It obtained from various
species of acacia, growing mainly in Africa. According to recent research, aldobionic acid C is an important component of gum arabic.12Н20О12which, upon acid hydrolysis, gives d-glucuronic acid associated with galactose.
Cherry gum glue secreted by cherry, plum and
apricot trees. The chemical composition is very similar to gum arabic.
Gums are used in the confectionery industry as adhesives and stabilizers for jewelry, for the preparation of special products with a rubber-like structure, such as chewing candies, for diabetic confectionery.
In the practice of confectionery production, edible vegetable gums are used abroad, known by various names: chikli-gum, gum-karaya, cholla-gum, etc.
VTU 382 MPPT USSR. Pectin food.
GOST 6470-53. Agar.
Zikeev BV, Water Recycling non-fish raw, Picard schepromizdat, 1950.
Ognyan new Il., Karakolev T., M. Marinov, VTRHU, Some peculiarities of pektinovato zheleobrazuvane. Sofia, 1952.
Confectionery Technology, ed. prof. AL Rapoport, Part I, Pishchepromizdat, 1951.
Advances in Chemistry Series 11, Natural Plant Hydrocolloids, ACS, Washington, 1954.
Hottenroth B., Die Pektine und ihre Verwendung, Munich, 1951.
Kertesz Z. L., The Pectic Substances, New York, 1951.
Maass H., The pectins, Braunschweig, 1951.
Emulsion, emulsifiers and diluents
Under emulsions realize a uniform mixture of two mutually insoluble and immiscible liquids together. The emulsions * individual small droplets of one liquid surrounded by another liquid.
Fluid in fragmented condition is called the dispersed phase and the liquid forming the continuous phase, called the dispersion medium.
Fats with water can form two types of emulsions: fat in water, usually denoted “oil-water” or “fat-water” and water in fat, usually denoted “water-oil”. In oil-water emulsions, fat is the dispersed phase, and water is a dispersion medium, and in water-oil emulsions, on the contrary, water is the disperse phase, and fat is a dispersion medium. Emulsions of one type can be converted into emulsions of another type. For example, when churning cream, the oil-in-water emulsion partially transforms into a water-in-oil emulsion.
To obtain stable concentrated emulsions, stabilizers (emulsifiers) must be introduced into the mixture, which form a protective adsorption layer on the surface of the individual droplets of the dispersed phase.
With the introduction of water-soluble emulsifiers, oil-water emulsions are formed, and with the introduction of fat-soluble emulsifiers, water-oil.
Particularly good emulsifying ability possess so-called balanced emulsifiers, in which the ratio of the lipophilic (hydrophobic) groups (fatty acid radical) and hydrophilic groups corresponds emulsion type.
Balanced emulsifiers are thinners chocolate and candy masses. The role of thinners, according to the data of academician P. A. Rebinder, is that they, being adsorbed on the coagulation centers of solid particles, cause complete solvation by the dispersion medium, eliminating the possibility of coagulative adhesion, and cause its greatest fluidity.
Dilutes the ability of diluent is determined by any viscometer and calculated according to the formula
where: - thinning ability;
ƞ1 — viscosity in puazah chocolate mass prior to the introduction of the thinner;
ƞ2 — viscosity in poises after the introduction of the diluent.
To determine the diluting ability, it is necessary to take the chocolate mass (well mixed) with the temperature 40 °, containing 30 — 32% fat.
Characteristics émwlgatorov and razjïjïteley
In the confectionery industry, proteins, phosphatides, gum and saponins are used as emulsifiers, which are part of the prescription mixture and are not specifically introduced as emulsifiers.
As emulsifiers and thinners, phosphatides and synthetic surfactants are usually specifically added.
Phosphatides from soy lecithin is used. Soy lecithin is obtained by hydration of soy oil. It is a mixture of lecithin and kephaline
where R1 and R2 - residues of fatty acids.
Kefalin belongs to the same group of compounds as lecithin, but in its composition instead of choline [BUT (CH3) 3NСН2SN2OH] number includes an amine (NH2SN2SN2HE). Kefalin is a-glycerol phosphoric acid derivative.
Product lecithin contains about 60% lecithin and Kefalonia and about 40% fat. The oil increases the resistance of lecithin in storage. Soy Lecithin is a good emulsifier and a diluent. His diluting the ability of the introduction of 0,3% by weight of chocolate mass not less than 3.
(Gidrofilʹnye Lipiny the polyglycerin)
Hydrophilic Lipiny on polyglycerol obtained by the transesterification of vegetable oils polyglycerol.
Typically, for an emulsifier ARSRIF originate from triglycerides with some content of diglycerol.
Primernaя formula gidrofilьnыh lipinov of poliglicerinah
where R is the fatty acid radical.
The dilution ability with the introduction of 0,3% by weight of chocolate mass is not less than 2,4.
Tverdıy emulsifier T1
T1 solid emulsifier is mainly a mixture of mono- and diglycerides. He is a weak diluent.
The approximate formula is as follows:
The approximate formula is as follows:
Hydrophilicity and lipophilicity of an emulsifier depends on the ratio of mono- and diglycerides.
where R is the radical of stearic acid.
Emulsifier T2 is very weak diluent.
Oxidized oil (polymerized)
These emulsifiers are obtained by the oxidation of vegetable oils with a high iodine number at a temperature of about 250 ° prior to the beginning of gelation at room temperature. They produce water-in-oil emulsions.
These oils are good emulsifiers and diluents.
Oxidized oils for bakery products
These oils are obtained by the oxidation of a mixture of equal quantities of oils with a high and low iodine number at a temperature of 160 - 170 ° for 6 hours.
They are used to improve the structure of the baked goods.
Clayton V., Emulsions. Their theory and technical applications. Translation from English ed. Acad. P. A. Rebinder, ed. foreign literature, xnumx.
Kozin, NI, Food emulsion Pshtsepromizdat, 1950.
Berkman S. and Е g 1 о f f G., Emulsions and Fooms, Edit. Reinhold.. New York, 1947.
Kuhn A., Kolloidchemisches Tasö ^ ienbuch, 4, Auflage,
Akad. Publishing Company, Leipzig, \ l 953.