RU2308209C2 - Method of milk deoxidization for imparting physiologically active properties to the same - Google Patents

Abstract

FIELD: food-processing industry, in particular, milk deoxidization process.

SUBSTANCE: method involves providing electrical milk deactivation on the basis of diaphragm-free (membrane-free) electrolysis without utilization of electrolytes and utilizing natural milk mineralization; performing electrolysis process using electrolysis unit having similar flat graphitic electrodes until milk acidity reaches predetermined values in Turner degrees. Automatic repolarization of electrodes allows problems connected with labor-consuming cleaning of electrodes from low-soluble deposits to be avoided.

EFFECT: simplified construction of diaphragm-free electrolysis unit and, accordingly, reduced process for milk activation, increased thermal stability, high redox potential, and increased physiological activity of resultant product.

2 cl, 2 dwg

Description

The invention relates to the food industry, in particular, can be used to deoxidize milk and give it additional heat resistance and physiologically active properties.

It is known [1] that standard milk should have a specific gravity at 20 ° C of 1.029-1.034 g / cm3; Turner acidity not higher than 22 °; fat content of at least 3.2%. Fresh milk (16-16.5 ° T) has a physiologically substantiated biology of mammalian buffering from rapid souring (several hours depending on air temperature and the initial degree of bacterial seeding). But over time, due to the work of lactic acid bacteria, it is acidified to 100 or more degrees Turner. Milk sugar turns into lactic acid, proteins denature, milk coagulates and turns into a lactic acid product. To prolong the buffering time of fresh milk, it is usually cooled or pasteurized.

An alternative to this process is modern developments in the electrochemical activation of aqueous solutions (deoxidation of milk, in particular). Their essence is that the processing of milk in an electric activator allows you to raise the pH of milk to the desired level and, thus, restore the required level of acidity. As a result, the acidity of milk on the Turner scale can always be within the required limits. At the same time, the heat resistance of milk increases, which increases the yield of dry product during heat treatment of electroactivated milk.

However, the existing Russian patented technologies for the electrochemical deoxidation of milk (No. 2043041, No. 2057435) cannot be taken as priorities, since the present invention is based on the principle of membrane-free activation, and these patents are based on the principle of membrane activation, which implies well-known design features of the use of buffer anolyte solutions ( 2). And this means a significant addition of alkali metal cations to the initial chemical composition of milk, which in principle can be considered as the so-called "falsification" of dairy products.

Therefore, the development of a membraneless activator known in the technical literature (3), which allows one to restore the initial acidity of milk by the electrochemical method due to the chemistry of salts (electrolytes) contained in the milk, without the use of extraneous electrolytes, can be taken as a prototype.

However, this development cannot be applied in principle in the modern production of dairy products for the main reason that the anodes of this electrolyzer are made of aluminum. And this circumstance implies the active dissolution of such an anode according to the theory of membraneless electrolysis of aqueous solutions of the third group [4], which can be represented as follows:

Cathodic process Anode process Discharge H ₂ O + F → 1/2 H ₂ + OH ^- 1 / k D ^k -F → 1 / k D Transfer 1 / p nA ^{p +} -1 / k (1-n) D ^k- -1 / p nA ^{p +} + 1 / k (1-n) D ^k- Sum 1 / p A (OH) _p - (1-n) / kp A _k D _p + 1/2 H _2- H ₂ OF -n / kp A _k D _p + 1 / k D + F The total process in solution -1 / kp A _k D _p -H ₂ O → 1 / p A (OH) _p + 1 / n D + 1/2 H ₂

where A is a cation; D is an anion; F is the amount of electricity (A / h); p ⁺ is the cationic charge; k ^- is the anion charge; n is the number of ions.

For milk, this process can be interpreted as follows.

Milk always contains a significant amount of chlorides, nitrates, phosphates and sulfates. In the process of electrolysis of milk solutions of these salts in the cathode zone (at the cathode electrode), complete hydrogen reduction occurs (released in the form of small gas bubbles), as well as the reduction of Na and K cations with the formation of their alkaline compounds. In the anode zone there is a discharge of oxygen and chlorine ions, as well as sulfur, nitrogen and phosphorus. In this case, anions containing sulfur, nitrogen and phosphorus (SO ₄ ^- , SO ₃ ^- , NO ₃ ^- , NO ₂ ^- , PO ₄ ^- PO ₃ ^- and others), standing on a scale of electrode potentials higher than oxygen, are oxidized at the anode in first of all, they remain in the solution or are isolated from it in the form of gaseous oxides, and chlorine, which has an electrode potential lower than oxygen and therefore discharges at a lower rate, remains in the solution in the form of active chlorine for a longer time (with the formation of active chlorine-oxygen oxidizing agents that disinfect activated milk). Due to the quantitative predominance of sulfates, phosphates and nitrates in milk relative to chlorides, a solution is metastable in the physicochemical aspect, but sufficiently stable in time, with a significant predominance of alkaline properties and a clearly expressed negative potential.

But this position can be so optimal only in the case of insoluble anodes. The main disadvantage of the prototype is just a highly soluble aluminum anode, which saturates the milk with aluminum hydroxides, which over time can make it practically poisonous.

In addition, a structural drawback of the hydraulics of the prototype electrolyzer is a change in the direction of the duct (from ascending to descending) leads to an increase in clogging of the device (foam with hydrogen bubbles having a floating effect on the cathode, and deposits of milk proteins on the anode). This makes the operation of the device virtually periodic, rather than continuous.

The design of a filmless (membraneless) electrolyzer proposed in this invention allows the inventive method of deoxidizing milk to be carried out without the aforementioned defects. A feature of the electrolyzer circuit is the use in it of identical (symmetrical) and insoluble graphite electrodes with a direct current source with periodic automatic polarity reversal.

The diagram of the device is presented in figure 1.

The explication to figure 1 "Scheme of the electrolyzer with minimal equipment"

1 - removable cover complete with electrodes and power terminals (current 380 V);

2 - a plastic case;

3 - graphite flat identical electrodes;

4 - zone of the duct (activation);

5 - drain pipe;

6 - inlet pipe;

7 - centrifugal milk pump;

8 - DC power supply with automatic polarity reversal of electrodes;

9 - stand.

The arrows indicate the direction of the duct from the bottom up. This is an indispensable condition for the electroactivation process. Activation can go in a closed circuit or with a drain in an open container. The size of the electrodes and the size of the activation zone are set in relation to the required power of the electrolyzer according to the corresponding hydraulic and electrochemical calculations.

The following is an example of the electrochemical processing of milk.

Electroactivation is carried out on a diaphragmless (memorless) electrolyzer with identical flat graphite electrodes with a milk flow rate of 300 l / h. DC voltage 24 V, current strength 15 A, initial milk acidity according to Turner scale 17.5 °, ORP + 220 mV. The temperature of the milk is 26 ° C. The results of milk electrolysis are presented in the table.

Physico-chemical characteristics of milk Raw milk Activated milk Acidity in degrees Turner 17.5 16.5 Heat resistance in alc. samples 68 75 The density of milk in g / cm3 1,029 1,029 The fat content of milk in% 3,5 3.5 * The protein content in% 3.4 3.4 Sugar content in% 4.8 4.8-4.85 * Redox potential in mV +220 -350 Milk deoxidation rate in degrees / hour / liter - 0.0033 * Milk acidification rate in degrees / hour / liter 0,0005 0.00037 *

According to the table, it is seen that at the outlet of the electrolyzer, milk has an acidity of 1 degree Turner lower.

The heat resistance of milk immediately (from the beginning of the activation process) increases to 75 or by 7 units and remains at this level, which corresponds to an increase in the yield in the processes of its heat treatment by 1.5-2.5% according to the literature [1].

The density and fat content of activated milk during electroactivation do not change relative to the original.

However, it is noteworthy that while maintaining the overall percentage of fat content, the proportion of solid fat is somewhat reduced relative to the liquid phase. At the same time, the size of nodules of fat structures is reduced from 10,000 nm to 1,000 or less.

The sugar content is also (by dry residue) almost at the level of the source milk. At the same time, a significant leptoleptic sensation of increased sweetness of activated milk is observed, which is explained by a partial replacement of lactose with its isomer lactulose (in the cathode zone), and decay into glucose and galactose (in the anode zone), which have a sweeter taste,

But the most important thing is that the recovery potential (ORP) of the processed milk changes from positive to negative (from +220 to -350 mV). This circumstance allows us to state the fact that a product with membrane-free electroactivation produces a product with previously unknown consumer qualities (with an acid corresponding to the acidity of fresh milk, it has a negative ORP characteristic of the reduction potential of fermented milk products).

In other words, the activated dairy product, remaining unchanged in terms of standard indicators of milk quality (density, fat content, protein content), acquires enhanced properties of physiological activity for the human body and mammalian animals, which according to published data [5] is within the ORP range from -150 to - 350 mV. This fact makes activated milk as easily digestible as fermented milk products. This is also indicated by our numerous ORP measurements of fresh cow's milk. It usually, at a pH of 16-16.5, has just such a potential.

Evolutionarily, this is easily explained by the need for quick (almost energy-free) absorption of calf nutrition. Chilled milk quickly loses this potential and it is usually set at the level of the initial ORP of the cow’s water consumed by the body.

In our experiments, these are limits from +250 mV to +450 mV.

The rate of milk deoxidation in the table, calculated for the range of 17.5-16.5 degrees Turner according to the formula V = T / L , where V is the rate of deoxidation, T is the change in acidity in degrees Turner, L is the flow volume, liter / hour, is 0.0033 degrees / hour / liter.

The relative rate of acidification of the source and activated milk is taken from the experimental table (figure 2).

The graphs of figure 2 shows the relative acidification rate of electroactivated and initial milk at a temperature of + 26 ° C. Obviously, the general trend of the graphs is qualitatively identical, but the curve of electroactivated milk is always below the curve of the source milk. That is, the acidification of electroactivated milk is constantly at a much lower rate. And the greatest relative difference between them is observed at the beginning of the acidification period.

Calculations show that the rate of deoxidation in terms of 1 l / h of activated milk is 6.6 times higher than the rate of the acidification process. In other words, an electric activator capacity of 300 l / h is sufficient to maintain a constant acidity of 1980 liters of feed milk at 17.5 degrees Turner.

Literature

1. Commodity research and examination of milk and dairy products. Textbook, M. Publishing house "Mart", 2001, 128 pages

2. Portable bioelectroactivator "ESPERO-10". Manual. Tashkent, NPF Espero. 13 sec

3. M. Benson "Electrically neutralization of milk." Dairy industry, 1948, No. 8, p. 37-40.

4. Popov V.M., Filinchuk V.I. Electrochemical technology for changing the properties of water, pp. 26-27.

5. Bahir V.M. Electrochemical activation: purification of water and obtaining beneficial solutions. VNIIIMT, 2001, “Marketing Support Services,” 176 pp.

Claims (2)

1. The method of electroactivation of milk, including the use of a non-diaphragm electrolyzer to bring the acidity of milk in degrees Turner to the specified values while increasing the degree of its heat resistance and lowering the redox potential, characterized in that the activation of milk is carried out against the background of its own mineralization when performing an electrolyzer with the same flat graphite electrodes. 2. The method according to claim 1, characterized in that the electrodes are installed with the possibility of their polarity reversal.

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