Acids are added in the manufacture of certain confectionery products to give them a taste of the inherent fruit and berries.
For this purpose, use wine (tartaric), citric, lactic and malic acid. All these acids except lactic, crystalline.
Trading lactic acid is a solution of a lactic acid concentration of 40-70%.
As used in the confectionery industry crystalline acid used interchangeably; Unlimited use of lactic acid. It is used in products such moisture introduction where the product together with the acid does not impair its quality and does not complicate the process, for example, fruit pulp for acidification in the production of candy, caramel, fruit jelly fillings.
Sour taste sensation due to the presence of hydrogen ions. However, when determining the coefficients of the interchangeability of different acids can not only come from the degree of dissociation. It was found that the weaker the acid, the lower the concentration of hydrogen ions, at which begins to be felt sour taste (the threshold of sensation).
Table. 87 shows the values of the threshold sensation (by Pisarev) and acid dissociation constants that are used in the confectionery industry.
87 Table. Threshold and feelings acid dissociation constant
|acids||The dissociation constant||threshold of feeling|
|pH||the molar concentration of acid in MMOL 1 l||the amount of acid in grams per ml 100|
|Dairy||1,37 * 10-4||3,45||2.7||0,0245|
|Wine||1,04 * 10-3||3,35||1.2||0,0160|
|Lemon||8,4 * 10-4||3,32||0,93||0,0178|
|apple||3,9 * 10-4||3,19||4,3||0,0576|
|Phosphorous||7,9 * 10-3||2,89||1.6||0,0157|
Relative acid concentration determining threshold sensations can be shifted in confectionery products with a more intense flavor and the presence of these substances masking the sour taste. Therefore, for the acidification of certain confectionery various acids dosage should be installed in practice.
Here is the dosage of acid (by Pisarev) in caramel, giving identical flavor (Table. 88).
88 Table. Dosage caramel acids
|acids||Identical to taste solutions of acids in grams of acid per ml 100||Identical caramel taste upon acidification with various acids in% by weight of caramel acid|
Inverting the ability of different acids that should be considered when acidification of confectionery and especially the caramel mass. For a rough estimation of the ability inverts acids in Table. 89 inversion coefficients are different acids Ostwald. The numbers in this table represent the relative values of the constants inversion rate, the value for hydrochloric acid is taken as one hundred.
89 Table. The coefficient inversion of various acids on Ostwald
For the preparation of invert sugar, starch syrup substitute, is used as catalyst in hydrochloric acid, with subsequent neutralization.
To this should be applied chemically pure or technical hydrochloric acid produced electrolytically (GOST 857-41).
Technical acid should contain:
a) at least hydrochloric acid 31%;
b) iron no more than 0,01%;
c) not more than arsenic 0,0002%;
g) of sulfuric acid in terms of SO4 not more 0,005%.
Wine (tartaric acid) (C4Н6О6) - Dibasic dihydroxy acid. Trading tartaric acid is a dextrorotatory isomers thereof. It crystallizes as colorless transparent prism monoclinic system. It does not smell, taste pronounced sour. The share of 1,7598, 150,09 molecular weight. The aqueous solution rotates the plane of polarization to the right. For 20% solution of α the angle of rotation of the solutionD20— 12°.
Melting point tartaric acid 170 °. Molten acid during solidification becomes amorphous modification. When heated above two molecules 170 ° right tartaric acid splitting off a water molecule, in moving dvuvinnuyu representing a resinous mass.
Boiling point at atm 1 25% solution of tartaric acid solution ° 102,2, 50% for strength - 106,7 °.
Tartaric acid is very soluble in water. Its solubility increases with increasing temperature (see Table. 90). The alcohol dissolves it, but worse. The air is practically insoluble.
90 Table. The solubility of tartaric acid based on temperature
|Temperature in ° C||Content in% tartaric acid to a solution of||Temperature in ° C||Content in% tartaric acid to a solution of||Temperature in ° C||Content in% tartaric acid to a solution of|
Dependence of specific weight aqueous solution of tartaric acid concentration is given in Table. 91.
91 Table. Dependence of specific weight aqueous solution of tartaric acid concentration
|Specific gravity of solution||The amount of tartaric acid in g / l||Specific gravity of solution||The amount of tartaric acid in g / l||Specific gravity of solution||The amount of tartaric acid in g / l|
Table. 92 is the refractive index of pure solutions of tartaric acid.
92 Table. The refractive index of pure tartaric acid solutions of different concentrations at 20 °
|The amount of tartaric acid in solution in 100 ml g|
|The amount of tartaric acid in solution in 100 ml g|
Technical specifications for tartaric acid. According to the standard
tartaric acid must meet the following requirements.
- Appearance - colorless or with slightly yellowish shade, large or small crystals and powder.
- Upon dissolution of the acid in distilled water should yield a clear solution containing no solids and odorless.
- Tartaric acid content on dry substance at least 99%.
- Foreign matter:
a) an ash content of not more than 0,5%;
b) the heavy metal content of not more than 0,0005%, including no more than arsenic 0,00014%;
c) the content of free sulfuric acid is not more 0,05%;
d) hydrochloric acid content of not more 0,02%;
d) lead salts are not allowed.
Storage conditions. Well dried tartaric acid should be stored in a dry place. The wet tartaric acid and its solutions are rapidly destroyed by the action of various microorganisms.
Citric acid (C6H8O7) - Tribasic oxyacid crystallizes from aqueous solutions with a water molecule in the form of colorless transparent rhombic prisms. It does not smell, taste pronounced sour. The proportion of an anhydrous acid 1,54, 192,12 molecular weight, molecular weight aqueous acid 210,14.
The melting temperature of the aqueous citric acid 70-75 °, anhydrous-153 °. In 100 ° aqueous acid loses water of crystallization. Dehydrated citric acid is obtained again by recrystallization in an anhydrous form. When heated to 175 ° citric acid molecule of one molecule of water is separated and the acid is converted to an unsaturated acid okanitovuyu.
Citric acid is very soluble in water, its solubility increases with increasing temperature (see Table. 93). Citric acid is soluble in alcohol; in parts of the 100 80% solution of alcohol at 15 87 ° dissolves parts of aqueous citric acid; in parts of absolute alcohol 100 43 dissolves part of the anhydrous acid.
93 Table. Citric acid solubility versus temperature
|Temperature in ° C||The content of citric acid to a solution of H||Temperature in ° C||The content of citric acid to the solution in%||Temperature in ° C||The content of citric acid to the solution in%|
The dependence of the specific gravity of aqueous solutions of citric acid concentration presented in Table. 94.
Specifications for citric acid. According to the standard (GOST 908-41) citric acid must meet the following requirements.
Depending on the method of crystallization produced food citric acid:
a) small crystals;
b) in the large crystals.
Citric acid should be colorless or with a slightly yellowish white crystals; weak solutions (1-2% -s) pleasant sour taste.
Upon dissolution of the acid in distilled water solution must be prepared transparent odorless.
The dependence of the specific gravity of aqueous solutions of citric acid concentration
|Specific Gravity 15 ° C||The amount of citric acid in g / l||Specific Gravity 15 ° C||The amount of citric acid in g / l||Specific Gravity 15 ° C||The amount of citric acid in g / l|
citric acid content should be at least taken into 99% hitch based on citric acid with one molecule of water of crystallization (C6Н807) • Н2О.
a) ash no more than 0,5%;
b) sulfuric acid (free) Not more than 0,05%;
c) not more than arsenic 0,00014%;
d) should not contain ions and alkaloids: heavy metals zhelezistosinerodistovodorodnoy acid, oxalic acid and barium.
Storage conditions. Citric acid should be stored in
dry place. During transport must be protected from moisture.
Malic acid (C3H6O5) Or dibasic oksiyantarnaya-hydroxy acid derived from plants (tobacco), it is laevorotatory isomer. It crystallizes in the form of needles with a melting point 100 °. Well soluble in water.
Synthetic malic acid is a racemic compound of the right and left of malic acid. It crystallizes easily levorotatory less soluble in water, it melts at a higher temperature (130-131 °). The molecular weight of 134,09; the proportion of levorotatory 1,595, 1,601 racemic. The levorotatory decomposes when heated over 140 °, and racemic over 150 °. Solubility of the racemic modification in water at 26 ° - 144 100 parts by weight parts by weight of solvent, and at 79 ° -411. In alcohol and ether readily dissolve.
Specifications for malic acid is the same as in the citric.
Lactic acid (C3Н603) - Monobasic hydroxy acid. There are two kinds of lactic acid: α-hydroxypropionic or
ethylidene-lactic acid (CH3SNONSOON) and .beta.-lactic or ethylidene-lactic acid (CH2ONSN2COOH). Industrial importance ethylidene-lactic acid, resulting in lactic acid fermentation as a racemic mixture. The molecular weight of lactic acid 90,08.
The crystalline form of lactic acid may be obtained by careful evaporation under high vacuum, the aqueous solution of lactic acid. The crystals melt at atmospheric pressure, forming a colorless, syrupy liquid specific gravity 1,21, odorless with a sharp sour taste.
Lactic acid is an unstable chemical compound. Depending on the production and storage conditions it is easy to form the products of dehydration, are usually united under the common name of lactic acid anhydride.
All products dehydration except dimolochnoy acid compounds are less valuable in taste regarding than the free lactic acid as its acidic properties are determined by the free carboxyl group.
When heated to lactic acid 90 ° mainly formed laktilmolochnaya acid to 100-110 ° in significant amounts of di-, tri-, tetra- and pentalaktilmolochnye acid, and by heating in vacuo to 180-250 ° - lactide.
The aqueous solution of lactic acid is an equilibrium system
The composition of the mixture depends on the concentration of lactic acid: the higher it is, the more it anhydrides.
Lactic acid and its anhydride are dissolved in water, alcohol and ether in all respects. The proportion of chemically pure lactic acid with 18 ° 50% -s' - 1,16; 90% -s' - 1,21.
On confectioneries lactic acid is in the form of aqueous solutions with acid concentrations 40-70% and a paste in which about 10% related acids in crystalline calcium lactate, which mechanically connects the lactic acid into a solid paste.
Specifications for lactic acid. According to the standard (GOST 490-41) lactic acid in quality, regardless of the concentration of acid is divided into the I, II and III grades.
The acid must meet the following requirements.
To be clear, no dregs sediment (which is allowed for the acid II and III grade availability opalescence or a precipitate, disappearing when diluted with distilled water 1: 1).
a) I grade acid should be colorless or slightly yellow in color;
b) Acid grade II can have a color ranging from yellow to yellowish- brown;
c) acid grade III can have color from yellow to dark brown.
Smell and taste:
a) acid should not have a sharp unpleasant odor due to the presence of impurities in it of volatile acids;
b) 1% aqueous solution of acid must have a sour taste clean, without foreign taste.
a) depending on the grade and concentration of acid, characterized by indicators, which are shown in Table. 95.
% acid, at least
|Pryamone- titratable lactic acid in%, not more||Ash% in not more than||% Nitrogen, not more than||Chromaticity, max|
|at a concentration in%|
Note. Colour stains of lactic acid is determined by comparison with the color of the solution obtained by mixing 0,1 N iodine solution and distilled water in proportions specified in the Table. 95;
b) by reacting the free sulfuric acid that metilviole- lactic acid solution does not appear green shade;
c) iron in terms of Re203 and 100% -ing lactic acid should be less than 0,05%;
d) Lactic acid should not contain hydrogen cyanide, arsenic, heavy metals (lead, copper) and zhelezistosinerodistovodorodnoy acid salts.
Zhuravsky GI, Novoselov, LV, Eliseev MI, Vulihmai AA, Zakharova G., Manufacture of food acids, Pishchepromizdat, 1953.
Citric acid GOST 908-41.
Lactic acid food GOST 490-41.
Pisarev NS, Acids and inversion issues hygroscopic and caramel color in the production, publication VNITI confectioners, 1938.
Reference chemist, vol. I, Goskhimizdat, 1951.
Chichibabin the AE, Organic chemistry, Gostekhizdat, 1953.
Landolt-Bornstein, numerical values and functions of physics, chemistry, astronomy and geophysics technology, Berlin, 1952.
The fragrance of confectionery reported natural and synthetic flavoring substances. With the introduction of aromatics products reported a certain taste.
By natural flavorings are products made from cocoa beans (cocoa liquor, chocolate, cocoa powder), roasted coffee, nuts, vanilla, fruit and berry wines and supplies. By natural aromatic substances include essential oils isolated from different plant efironosov.
By synthetic fragrances include fragrances obtained by methods of organic chemistry vegetable semi and fully synthetic products.
Some flavors can be classified as a natural or synthetic, depending on the method of their preparation.
Aromatic food essences called flavors representing alcoholic, hydroalcoholic solutions atsetinovye or mixtures of natural and synthetic fragrances. They are prepared according to the recipes approved by the Ministry of Industry of food products in Ukraine in coordination with the State Sanitary Inspectorate of Ukraine.
Essences for the confectionery industry are available single, double and quadruple concentration.
Food essences should be stored in a tightly sealed glass container in the exclusion of sunlight.
The duration of storage of food essences 6 months.
Essence is bottled in glass bottles with capacity up to 25 l. The bottles are placed in baskets, cages or wooden boxes with lids and lay straw, wood shavings or sawdust.
Establishment of smell and taste
Smell and taste flavors when tasting set of manufactured products. At the same smell and taste essences are best determined at the tasting (in sugar syrup) 0,2% solution essences and essential oils and synthetic fragrances - 0,03% solution or suspension.
The following essential oils can be used in the confectionery industry, if they are included in the recipe.
anise oil obtained from anise fruits. The composition of the oil comes up to 90% anethole. Contained in an amount 2,2-3,2% by weight of the fruit.
Greypfrutovoe oil prepared from fresh peel of the fruit. The composition of oil includes about 90% d-limonene. Oil is contained in an amount 0,06% by weight of whole fruits.
Pomerantsevoe oil extracted from the rind of the fruit of Citrus aurantium L. subsp. amara L. in the number 0,15% to the weight of the rind. The oil contains more than 90% d-limonene.
orange oil obtained from the peel of the fruit Citrus sinensis in the number 0,3%. The oil contains more than 90% d-limonene.
Mandarinovoe butter extracted from tangerine peel. Oil yield is 0,75-0,85% to the weight of the whole fruit. This oil consists essentially of d-limonene.
Peppermint oil distilled peppermint. The output from the 0,3 1,0% up. It contains not less than 50% menthol.
Oil of spearmint spearmint obtained in an amount of up to 0,7 1,5%. It contains carvone, linalool and linalyl acetate.
Koriandrovoe oil is prepared from the dried seeds in the amount of 0,8-1,1%. The main part of the oil is linalool (60-80%) \
(Плавления 80,5-81,5 °,
Boiling point 285 ° (not decomposed in the stream of carbon dioxide).
It soluble in aqueous solutions of carbon and sodium bicarbonate. Recrystallized from water.
Burbonal (Vanilalь) (4-oxy-Z-эtoksibenzalьdegid)
Температура плавления 77-78 °.
Pastry is not recommended due to the smell of a flower.
SN3 — СО — со — CH3.
It is used in the confectionery industry for communication products smell of butter. With alcohol and ether is mixed in all respects. Soluble at 15 4 ° in water volumes.
Isoamyl ether cinnamic acid
(SN3)2 = SN - SN2- SN2 — О — ОС — СН — СН — С6Н5.
It is used to enhance the flavor of the cocoa beans.
Т плавления 42,5 °,
Температура кипения 216 °
It crystallizes in colorless needle-like crystals and kolonkoobraznyh hexagonal system, which have a characteristic smell of mint and a cooling taste. In the water, poorly soluble in alcohol, ethyl ether, chloroform, fatty and essential oils - good.
It has the smell of hay. It melts at 67 °. It is used as an additive to other flavors to produce the characteristic flavor.
Goriaev MI, characteristic chemical compounds that make up the essential oils, ed. prof. GV Pigulevskaya, Academy of Sciences of the Kazakh SSR, 1953.
Kondratsky AP and NP Sokolniki, Manual for laboratory aromatic enterprises Pischepromiz- dates, 1953
Obukhov AN and Kondratsky AP, essential oil production technology, Pishchepromizdat, 1946.
Studneobrazuyuschie agent (gelling agents) used in the confectionery industry for making jelly products (marmalades, marshmallows, marshmallow, "jelly" of sweets).
The confectionery industry of the Soviet Union as gelling agents used agar, pectin and agaroid.
Foreign confectioneries as gelling agents are also used gelatin, alginic acid (and its connection), carrageenan extract and others.
A characteristic feature of this group of substances is their ability to form gels (gels) at certain conditions, the feature of which is that they are easy to take any shape imparted to them, forming a more or less solid structure.
Agar - mucilage contained in crimson algae (genus Anfeltia, Gelidium and others.), Native to the coastal waters of the White Sea and the Pacific Ocean.
To remove the pre-prepared agar seaweed (dried, cleaned of sand and silt from molluscs and shells, soaked and rinsed), digested in hot water with the addition of alkali. The resulting broth (bouillon agar) was filtered, cooled to complete zastudeneniya subjected to cutting, and subsequent additional purification of dehydration by drying or freeze drying.
Chemically agar is highly polymeric polysaccharide type compound having a chain-like molecule. Individual units it consist of galactose residues.
As part of the market of drugs agar except galactose are present usually calcium, magnesium, sulfur (organically bound), potassium, sodium, phosphorus and nitrogen in the form of various compounds.
After demineralization agar (removal of Ca, Mg, K, Na) is obtained by a complex organic complex consisting, on assumptions based on data from recent studies of the linear polysaccharide ether having the following formula:
The agar chain includes residues 9 d-galactose, linked 1: 3 glucoside bond. Chain ends residue L-galactose, which is associated with the preceding chain links through its carbon atom 4, sixth carbon atom it efirizovan sulfuric acid.
Agar is almost insoluble in cold water but swells therein as a colloid limited swelling (in this case air-dried agar binds water in 4-10-fold amount to its weight).
When boiled in water agar dissolves almost completely.
From aqueous solutions of agar can be precipitated with alcohol, acetone and electrolytes.
Hot water agar solution (sol) goes on cooling in jelly (gel), wherein the vitreous fracture. For lasting jelly, can be cut with a knife, it is sufficient to 0,3 1% of agar to the weight of the aqueous solution (depending on the ability of the sample studneobrazovaniyu agar).
When administered in a water-agar sugar solution obtained jellies, whose strength increases with increasing sugar concentration and with decreasing water content.
Agar-sugar-water jellies have a certain resistance against heat. Upon acidification of the gels their resistance against heat is sharply reduced. In the presence of acid hydrolysis the agar jelly, which weakens its ability to studneobrazovaniyu. Degradation studneobrazuyuschey agar capacity in an acidic medium develops with particular intensity by increasing the ambient temperature, since 60-70 °.
According to current state standards 6470 53-agar can be released for sale in the form of porous plates of thickness less than 20 mm, the film is not more than 0,5 mm thick, grits, flakes, powder.
Its color from white (for a premium) to yellow and light brown (for grade I).
Agar and its aqueous solutions should not be foreign smell and taste.
Humidity agar should be no more than 18%. For agar obtained by freezing, humidity is allowed up to 20%
The ash content in the highest grade agar should be no more than 4,5%, in the I-grade less than 7%.
The amount of nitrogenous substances, respectively, and to 1 2%.
Ability to studneobrazovaniyu agar is characterized by the load, which maintains the standard jelly (0,85% of absolutely dry agar, 70% of sugar, 29,15% water). It should not be less than 1000-1400 Mr. Valenta on the device to determine the strength of the jelly.
Melting point 0,85% aqueous agar jelly should not be less than 80 °, and the temperature of its zastudeneniya not less than 30 °.
The confectionery production conditions temperature zastudeneniya 1% Jelly strength of agar containing 60-70% sugar (about 1% and tartaric or citric acid) is within 35- -40 °.
Importance of using agar in the confectionery industry it has a high degree of purification, in particular - no color (which is necessary to generate background colorless products), no abnormal smell or taste.
Agar must be packed in wooden crates (lined inside with thick paper), of a net weight of not more than 20 kg, or in cardboard boxes with net weight of not more than 10 kg.
Agar should be stored in dry, well ventilated warehouse, which has no sharp fluctuations in temperature and relative humidity of not more than 80%
Shelf life of the agar for one year.