RU2461207C1 - Method for production of fried acorns - Google Patents

Abstract

FIELD: food industry.

SUBSTANCE: invention relates to vegetable dehydration and food-concentrates industry and may be used for production of coffee beverages with acorns addition. The method envisages raw material inspection, sorting, washing, peeling, cutting, frying with superheated steam under atmospheric pressure. Frying with superheated steam is performed in four stages: at the first stage acorns cut into cubes with linear size up to 3-5 mm are heated up to 345 K, treated with superheated steam with a temperature equal to 423 K at a rate of 1.85 m/s during 8 minutes; at the second stage treatment is performed with superheated steam with a temperature equal to 433 K at a rate of 1.3 m/s during 8 minutes; acorns cubes heated till the temperature is equal to 355 K; at the third stage treatment is performed with superheated steam with a temperature equal to 443 K at a rate of 0.8 m/s during 2 minutes, acorns cubes heated till the temperature is equal to 358 K; at the four stage treatment is performed with superheated steam with a temperature equal to 453 K at a rate of 0.35 m/s during 6 minutes; acorns cubes heated till the temperature is equal to 378 K; then acorn cubes fried till final moisture content equal to 3% are milled for further usage.

EFFECT: invention allows to produce fried acorns with high content of valuable thermolabile substances, intensify the process of production and enhance its heat effectiveness.

1 dwg, 1 tbl, 1 ex

Description

The invention relates to a vegetable drying and food concentrate industry and can be used in the manufacture of coffee drinks with the addition of acorns.

The closest in technical essence and the achieved effect is a method of roasting coffee beans with steam [Patent 5681607 US, Int. Cl. ⁵ A23F 5/04; A23F 5/16; A23F 5/00 Process for roasting coffee beans with steam Maki, Yoshiaki (Suzuka, JP) Haruyama, Tsutomu (Mie-ken, JP). Filed: 07.26.1996. Date of Patent: 10.28.1997]. According to this method, coffee grains are roasted with superheated steam in two stages: in the first, for 50-300 s at a temperature of 251-400 ° C at a pressure of 6.5-20 bar; and on the second - for 60-800 s at a temperature of 251-400 ° C at atmospheric pressure.

The disadvantage of this method are: low quality indicators of the finished product due to the loss of valuable thermolabile substances due to high temperature and significant specific energy consumption.

An object of the invention is to improve the quality of the finished product and increase the thermal efficiency of the roasting process through the use of a four-stage process adapted to the basic kinetic laws of the process of roasting acorns with superheated steam, intensifying the roasting process and reducing the energy consumption for obtaining the finished product.

The object of the invention is achieved in that in the proposed method for the production of fried acorns, including inspection of raw materials, sorting, washing, peeling, cutting, frying with superheated steam of atmospheric pressure, the new is that frying with superheated steam of atmospheric pressure is carried out in four stages: at the first stage, acorns cut into cubes with a linear size of 3-5 mm are heated to a temperature of 345 K, treating them with superheated steam at a temperature of 423 K and a speed of 1.85 m / s for 8 min; at the second stage - superheated steam with a temperature of 433 K and a speed of 1.3 m / s for 8 minutes, while the cubes of acorns are heated to a temperature of 355 K; at the third stage - superheated steam with a temperature of 443 K and a speed of 0.8 m / s for 2 minutes, while the cubes of acorns are heated to a temperature of 358 K; in the fourth stage - superheated steam with a temperature of 453 K and a speed of 0.35 m / s for 6 minutes, while the acorns cubes are heated to a temperature of 378 K, then the acorns cubes fried to a final moisture content of 3% are crushed for further use.

The technical result of the invention is to improve the quality of the finished product through the use of step-by-step gentle modes, increase thermal efficiency and intensify the roasting process, and to reduce energy consumption for obtaining the finished product.

Figure 1 shows the kinetic laws of the stepwise mode of frying acorns with combined heat supply: a - curve of frying, which represents the dependence of moisture content on time; b - the curve of the speed of frying, which represents the dependence of the speed of frying from time to time; c - temperature curve, representing the dependence of the temperature of the product on moisture content; g - thermogram representing the dependence of product temperature on time.

The dried acorns used in the food industry, in their quality, meet the requirements of GOST 21537-76 "Oak acorns."

Appearance: peeled and peeled cotyledons of an ovoid-oblong shape. The outer side of the cotyledons is convex, grooved, and the inside is flat or slightly concave.

Dimensions, mm: length: 15-20, diameter: 7-12.

Color: light or dark brown.

Smell: absent.

Taste: sweetish at first, then bitter.

Ash content: no more than 3%.

Humidity: no more than 11%.

Mass fraction of untreated acorns, parts of the fruit peel: not more than 2%.

Mass fraction of crushed parts passing through a sieve according to TU 23.2.2068-89 with holes with a diameter of 3 mm, not more than 2%.

Mass fraction of mineral impurities (sand, earth, dust, pebbles, etc.): not more than 0.5%.

The presence of litter of rodents and birds: not allowed.

Mold and rot: not allowed.

The presence of a stable odor that does not disappear when aired is not allowed.

A method of manufacturing roasted acorns is as follows.

Acorns are washed in a fan washer. For more intensive washing of contaminated acorns in the washing bath of the machine, drilling is created by means of compressed air supplied to the perforated pipes. Washed acorns from the washing bath are moved by an inclined conveyor, in the upper part of which they are rinsed with water from the shower unit. When treating heavily contaminated acorns, you can increase their time in the wash zone by occasionally stopping the conveyor.

Then washed acorns are subjected to inspection and sorting, which are carried out manually on a sorting and inspection conveyor. Along with sorting, an inspection of raw materials is carried out, in which defective specimens (rotten, damaged, moldy, heavily contaminated), foreign impurities and objects are removed. Then the treated acorns are peeled and cut into cubes with a linear size of 3-5 mm.

Cutting acorns into cubes with a larger linear size than 3-5 mm, for example 7 mm, significantly increases the duration of frying and reduces the productivity of the line.

Cutting acorns into cubes with a smaller linear size than 3-5 mm, for example 1 mm, leads to the formation of a dusty mass during frying, uneven frying and, as a result, a decrease in the quality of the final product.

The acorns chopped into cubes are then roasted with superheated steam. Superheated steam has significant advantages over other coolants: high energy efficiency of the process, due to the possibility of recycling secondary steam; a decrease in the required amount of steam in the circulation circuit due to the higher specific heat capacity of the steam compared with the heat capacity of the air; the lack of oxygen in the superheated steam, which can significantly increase the temperature of the roasting process without a significant deterioration in the quality of the finished product; improving the quality indicators of the finished product by reducing the gradients of moisture content and increasing the ductility of the material [Ostrikov AN Roasting coffee with superheated steam. / A.N. Ostrikov, A.A. Shevtsov, V.M. Kravchenko, A.N. Zotov: Voronezh, state. technol. Acad. Voronezh, 2003. - 174 p.].

At the first stage, cut cubes of acorns with a linear size of 3-5 mm are heated to a temperature of 345 K when blowing with superheated steam at a speed of 1.85 m / s and a temperature of 423 K for 8 minutes (figure 1). In this case, physical and mechanical moisture is removed, i.e. moisture micro- and macrocapillaries and wetting moisture. The main parameter affecting the intensity of moisture removal during this period is the coolant speed. Therefore, it is most advisable at the initial moment of frying to use frying with a high coolant speed and a low heating temperature of the product. Roasting at the first stage most fully meets this requirement.

Heating the product to a temperature lower than 345 K, for example 335 K, reduces the efficiency of evaporation of physico-mechanical moisture. Heating the product to a temperature higher than 345 K, for example 355 K, leads to excessive overheating of the product and a decrease in its quality due to the decomposition of valuable thermolabile substances (vitamins, carbohydrates, amino acids, etc.).

Blowing the product with superheated steam at a speed of less than 1.85 m / s, for example 1.6 m / s, reduces the efficiency of removal of evaporated water vapor, and therefore reduces the efficiency of heat and mass transfer of the roasting process. Blowing the product with a stream of superheated steam at a speed greater than 1.85 m / s, for example 2 m / s, leads to an overdrying of the surface layers of the acorns cubes and the formation of a crust on the surface of the acorns, which makes it difficult to remove evaporated moisture.

The duration of the first stage (8 min) was determined experimentally by analyzing the obtained frying curves. The use of a longer duration of the first stage, for example 11 min, leads to an overdrying of the surface layers of the acorns cubes and makes it difficult to remove moisture contained in the central layers of the cubes. The use of a shorter duration of the first stage, for example 5 minutes, leads to the fact that not all physico-mechanical moisture is removed from acorns, which entails an increase in the duration of subsequent stages of frying and a deterioration in the quality of the finished product.

At the second stage, the pre-fried cut cubes of acorns are heated to a temperature of 355 K when blowing with superheated steam at a speed of 1.3 m / s and a temperature of 433 K for 8 minutes (Fig. 1). With the removal of physical and mechanical moisture, the velocity of the coolant, as a determining factor in the intensity of the process, loses its significance. Therefore, in the second stage, it is preferable to roast at a decreasing speed and increasing temperature of the coolant. Due to the fact that the temperature has the greatest influence on the removal rate of osmotic (intracellular) moisture, as a factor determining the intensity of internal moisture transfer, the product is heated with superheated steam to a temperature of 355 K. Heating the product to a lower temperature than 355 K, for example 345 K, reduces the efficiency of evaporation of osmotic moisture.

Heating the product to a temperature higher than 355 K, for example 365 K, leads to excessive overheating of the product and a decrease in its quality due to the decomposition of valuable thermolabile substances (vitamins, monosugars, amino acids, etc.).

Blowing the product with superheated steam at a speed of less than 1.3 m / s, for example 1.0 m / s, does not completely remove the vaporized water vapor, and therefore reduces the efficiency of heat and mass transfer of the roasting process. Blowing off the product with superheated steam at a speed greater than 1.3 m / s, for example 1.6 m / s, leads to an overdrying of the surface layers of acorns cubes and the formation of a crust on the surface of the particles, which makes it difficult to remove evaporated moisture.

The duration of the second stage (8 min) was determined experimentally as a result of the analysis of the obtained frying curves. The use of a longer duration of the second stage, for example 10 minutes, leads to an overdrying of the surface layers of acorns and makes it difficult to remove moisture contained in the central layers of particles. The use of a shorter duration of the second stage, for example 6 minutes, leads to the fact that not all osmotic moisture is removed from the cubes of acorns, which entails an increase in the duration of subsequent stages of frying and a deterioration in the quality of the finished product.

In the third stage, the pre-fried cut cubes of acorns are heated to a temperature of 358 K when blowing with superheated steam at a speed of 0.8 m / s and a temperature of 443 K for 2 minutes (figure 1). As the osmotic (intracellular) moisture is removed, the velocity of the coolant, as a determining factor in the intensity of the process, loses its significance. Therefore, in the third stage, it is preferable to roast at a decreasing speed and increasing temperature of the coolant. Due to the fact that the temperature is most affected by the rate of removal of polyadsorption moisture, as a factor determining the intensity of internal moisture transfer, the product is heated with superheated steam to a temperature of 358 K. Heating the product to a temperature lower than 358 K, for example 348 K, reduces the efficiency of evaporation of polyadsorption moisture.

Heating the product to a temperature higher than 358 K, for example 368 K, leads to excessive overheating of the product and a decrease in its quality due to the decomposition of valuable thermolabile substances (vitamins, monosugars, amino acids, etc.).

Blowing the product with superheated steam at a speed of less than 0.8 m / s, for example 0.6 m / s, does not completely remove the vaporized water vapor, and therefore reduces the efficiency of heat and mass transfer of the roasting process. Blowing off the product with superheated steam at a speed greater than 0.8 m / s, for example 1.0 m / s, leads to overdrying of the surface layers of acorns and forms a crust on the surface of the particles, which makes it difficult to remove evaporated moisture.

The duration of the third stage (2 min) was determined experimentally as a result of the analysis of the obtained frying curves. The use of a longer duration of the third stage, for example 3 min, leads to an overdrying of the surface layers of acorns cubes and makes it difficult to remove moisture contained in the central layers of particles. The use of a shorter duration of the third stage, for example 1 min, leads to the fact that not all osmotic moisture is removed from the cubes of acorns, which entails an increase in the duration of subsequent stages of frying and a deterioration in the quality of the finished product.

In the fourth stage, pre-fried cut cubes of acorns are heated to a temperature of 378 K when blowing with superheated steam at a speed of 0.35 m / s and a temperature of 453 K for 6 minutes (figure 1). As the polyadsorption moisture is removed, the velocity of the coolant, as a determining factor in the intensity of the process, loses its significance. Due to the fact that the temperature has the greatest influence on the rate of removal of monoadsorption moisture, as a factor determining the intensity of internal moisture transfer, the product is fried with superheated steam to a temperature of 378 K.

Heating the product to a temperature lower than 378 K, for example 368 K, reduces the efficiency of evaporation of monoadsorption moisture. Heating the product to a temperature higher than 378 K, for example 388 K, leads to excessive overheating of the product and a decrease in its quality due to the decomposition of valuable thermolabile substances.

Blowing the product with superheated steam at a speed of less than 0.35 m / s, for example 0.2 m / s, does not completely remove the vaporized water vapor, and therefore reduces the efficiency of heat and mass transfer of the roasting process. Blowing the product with a stream of superheated steam at a speed greater than 0.35 m / s, for example 0.5 m / s, leads to an overdrying of the surface layers of acorns cubes and the formation of a crust on the surface of the product, which makes it difficult to remove evaporated moisture.

The duration of the fourth stage (6 min) was determined experimentally as a result of the analysis of the obtained roasting curves. Using a longer duration of the fourth stage, for example 9 minutes, leads to overdrying of the cubes of acorns and excessive energy consumption. The use of a shorter duration of the fourth stage, for example 3 min, leads to the fact that not all monoadsorption moisture is removed from the cubes of acorns, which entails an increased final moisture content of the finished product and a rapid deterioration in its quality during storage.

Adapted in accordance with the basic kinetic laws of the roasting process, the coolant supply at the four stages of roasting the product allows you to choose rational roasting modes taking into account changes in the moisture content of the product during the roasting process.

Then fried to a final moisture content of 3% cubes of acorns are transferred for further processing.

A method for producing roasted acorns is illustrated by the following example.

Example

Acorns are washed in a fan washer. Then the washed acorns are subjected to inspection and sorting, which are carried out manually on a sorting and inspection conveyor. Next, acorns are peeled and cut into cubes with a linear size of ≈4 mm.

Then acorns cut into cubes are subjected to heat treatment with superheated steam. Moreover, the frying of cubes of acorns is carried out with superheated steam in four stages.

At the first stage, acorns cut into cubes with a linear size of 4 mm are fried with superheated steam with an initial temperature of 423 K to a temperature of 345 K at a coolant speed of 1.85 m / s for 8 minutes. In this case, physical and mechanical moisture is removed, i.e. moisture micro- and macrocapillaries and wetting moisture.

At the second stage, pre-fried acorns cubes are fried by a stream of superheated steam with an initial temperature of 433 K and a speed of 1.3 m / s for 8 min to a temperature of 355 K. In this case, osmotic (intracellular) moisture is removed.

At the third stage, pre-fried acorns cubes are fried by a stream of superheated steam with an initial temperature of 443 K and a speed of 0.8 m / s for 2 min to a temperature of 358 K. At the same time, polyadsorption moisture is removed from the acorns.

In the fourth stage, pre-fried acorns cubes are fried to a temperature of 378 K with a stream of superheated steam with an initial temperature of 453 K and a speed of 0.35 m / s for 6 minutes. In this case, monoadsorption moisture is removed from acorns.

Then, 3% acorns cubes fried to a final moisture content are passed on for further processing.

The table shows the chemical composition of fresh and fried acorns according to the proposed four-stage regimen (in terms of dry matter).

The chemical composition of fresh and fried acorns according to the proposed four-stage regimen (in terms of dry matter) Measured parameters Acorns Fresh Fried by the proposed method Total moisture% 38.10 ± 0.04 2.87 ± 0.02 Mass fraction of crude protein,% 2.55 ± 0.02 2.44 ± 0.02 Mass fraction of crude fiber,% 30.16 ± 0.02 27.83 ± 0.02 Ash% 3.26 ± 0.02 2.04 ± 0.02 Carbohydrates (total sugar),% 68.85 ± 0.02 67.68 ± 0.02 The content of NO ^3- , mg / kg 56.82 ± 0.02 38.11 ± 0.02 Mineral composition Sodium (Na), mg% 17.96 ± 0.02 15.45 ± 0.02 Potassium (K), mg% 109.68 ± 0.02 95.39 ± 0.02 Calcium (Ca), mg% 84.94 ± 0.02 77.36 ± 0.01 Magnesium (Mg), mg% 28.34 ± 0.01 24.78 ± 0.02 Iron (Fe), mg% 19.42 ± 0.02 16.34 ± 0.02 Phosphorus (P), mg% 19.64 ± 0.02 16.48 ± 0.02 Amino acid composition (essential) Valine, mg / 100 g 4.91 ± 0.02 4.28 ± 0.04 Isoleucine, mg / 100 g - - Leucine, mg / 100 g - - Lysine, mg / 100 g - - Methionine + cystine, mg / 100 g 28.90 ± 0.04 21.17 ± 0.02 Threonine, mg / 100 g 9.47 ± 0.04 6.30 ± 0.02 Phenylalanine + tyrosine, mg / 100 g 27.00 ± 0.02 19.35 ± 0.04 Heavy metal content Mercury (Hg), mg / g - - Lead (Pb), mg / g 0,052 ± 0,004 0.041 ± 0.002 Arsenic (As), mg / g - - Cadmium (Cd), mg / g - - Cesium (Cs ¹³⁷ ), mg / g - - Strontium (Sr ⁹⁰ ), mg / g - - Pesticide content HCCH, mg / kg - - DDT, mg / kg - - microbiological indicators KMAFANM, CFU / g 176 115 S. aureus, CFU / g - - BGKP (coliforms), CFU / g - - Vitamin Composition Thiamine (B ₁ ), mg% 0.116 ± 0.004 0.064 ± 0.004 Riboflavin (B ₂ ), mg% 0.498 ± 0.004 0.306 ± 0.004 Vitamin E, mg% 0,052 ± 0,004 0.029 ± 0.004 Vitamin C, mg% 53.178 ± 0.004 31,730 ± 0,004 Niacin (PP), mg% 1,570 ± 0,004 0.887 ± 0.004

As can be seen from the table, acorns fried by the proposed method, retained a significant amount of valuable thermolabile substances. This indicates the correctness of the choice of soft sparing temperature-hydrodynamic modes of frying, allowing to preserve the native properties of acorns to the maximum extent.

Thus, the use of the proposed method for the production of fried acorns allows you to:

- receive fried acorns with a high content of valuable thermolabile substances (vitamins, monosugar, amino acids, etc.);

- intensify the process and increase its thermal efficiency;

- reduce energy and labor costs for the production of fried acorns due to the use of a four-stage process adapted to the basic kinetic laws of the process of frying acorns with superheated steam.

Claims (1)

Method for the production of fried acorns, including inspection of raw materials, sorting, washing, peeling, cutting, frying with superheated steam of atmospheric pressure, characterized in that frying with superheated steam of atmospheric pressure is carried out in four stages: at the first stage, acorns are cut into cubes with a linear size 3-5 mm, heated to a temperature of 345 K, treating them with superheated steam with a temperature of 423 K and a speed of 1.85 m / s for 8 min; at the second stage - superheated steam with a temperature of 433 K and a speed of 1.3 m / s for 8 minutes, while the cubes of acorns are heated to a temperature of 355 K; at the third stage - superheated steam with a temperature of 443 K and a speed of 0.8 m / s for 2 minutes, while the cubes of acorns are heated to a temperature of 358 K; in the fourth stage - superheated steam with a temperature of 453 K and a speed of 0.35 m / s for 6 minutes, while the acorns cubes are heated to a temperature of 378 K, then the acorns cubes fried to a final moisture content of 3% are crushed for further use.

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