The subject matter of the present invention is a novel phosphate mixture, characterized by its excellent solubility in water and aqueous solutions containing salt (brines).
Phosphate salts have been used for a long time in the food industry. A great many special uses for phosphates in the food industry, for example their use for the processing of meat, fish, beverages and milk products, are described in the article “Phosphates in food” by Ricardo Molins, CRC Press, 1991. Phosphates represent so-called functional food additives, meaning their use depends on the area of application and is specifically directed toward diverse problem definitions. Responsible for such a wide use spectrum of the phosphates are their properties, which include:
A buffering effect (for the pH adjustment as well as the pH stabilization);
The capacity to form complexes on multi-valent cations and thus indirectly connected the function as anti-oxidant (through bonding of pro-oxidative cations) and as anti-microbial substance, as well as for influencing the consistency;
The function as polyanion in an interaction with different protein fractions of individual food items;
The capacity for souring (for pH adjustment in beverages and as souring component in leavening agents).
The respective function depends on the structure and/or the condensation degree, the pH value and the cation of the salt.
The chemical terms used for the individual phosphates in this invention are as follows:
According to the present invention, KTPP, TKPP, NPP, MNP and/or MKP are used as phosphate salts.
In addition to the direct admixture of phosphates in the form of a dry substance (powdered form) in the food industry, liquid forms are used for a number of application cases, so-called phosphate solutions or phosphate brines, for example in the area of meat processing (e.g. the production of pickled items for cooking), as well as for treating seafood products (fish filet, crustaceans, types of mollusks, etc.). Phosphates must have the following critical properties to be able to use them effectively and with high functionality:
The novel phosphate mixture is characterized in that it comprises the following components:
Essential to the invention is the use of a so-called clear soluble potassium polyphosphate which is extracted from a melt having a P2O5 content of 46.0 to 47.0%, preferably 46.4 to 46.8 and especially preferred 46.4% and stoichiometrically consists of a mixture of potassium phosphate and tetrapotassiumdiphosphate at a ratio of approximately 3:1. The melt is produced by mixing corresponding amounts of potassiumphosphates, in particular tripotassiumphosphate with P2O5 and heating it to the melting temperature and leaving it at this temperature until the reaction balance is adjusted. A mixture is thus formed which contains only small amounts of orthophosphates and diphosphates in addition to potassiumphosphate and tetrapotassiumdiphosphate, as well as the harder to dissolve potassiummetaphosphates which are responsible for the cloudiness of the polyphosphate solution outside of this narrow range; see phase diagram by J. R. van Wazer, Phosphorous and its compounds, Vol. VI, page 608.
In Tables 1 and 2, the recipe for producing the mixture according to the invention are listed, taking into account that the desired pH value of the mixture according to the invention can be adjusted with the aid of Na/K orthophosphates (Table 1), as well as with Na/K diphosphates (Table 2).
The main components (sodiumpolyphosphate and potassiumtripolyphosphate) of the mixture according to the invention by themselves show a high solubility limit in water (>50%) (see Table 3).
Furthermore, individual main components of the mixture according to the invention have good solubility properties even in brines (see Table 4; Example 1).
The phosphate types and/or phosphate combinations known so far exhibit individual properties of the aforementioned required properties, but not all of them:
Thus, the KTPP mentioned in Table 3 is highly soluble (64 g/100 g solution) and is also soluble in the presence of cooking salt, but is cloudy.
The sodiumpolyphosphates mentioned in Tables 3 and 4 are also highly soluble, but lack the functional shares of diphosphates and triphosphates listed under requirement 5.
By producing a mixture comprising both main components of the mixture according to the invention and an additional phosphate for the pH adjustment (orthophosphate or di-phosphate), synergic effects are used that increase the solubility in highly concentrated brines.
The synergic effect of the mixture according to the invention and its impact on the solubility in salt-containing solutions are demonstrated with the aid of 3 examples shown in Table 4.
Example 1 and Example 2 show a traditional sequence for the solubility, meaning the phosphate type and/or the phosphate combination is dissolved as the first component in water. Following this, the respective amount of sodium chloride (cooking salt) is dissolved.
In the food industry, e.g. for producing cooked ham, it is standard procedure to first dissolve the phosphate in water and then add the cooking salt. The so-called inverse preparation technique is understood to mean that the cooking salt solution (brine) is first produced and the phosphate is then added.
Example 3 additionally shows the synergic effect of the mixture according to the invention. With this mixture, an “inverse sequence” can be used for the solution, meaning the phosphate is stirred into a salt solution and is soluble—a property that phosphates or phosphate combinations known so far do not have.
Table 4: Synergistic effect of the mixture according to the invention on the solubility and stability in salt-containing aqueous solutions (brines).
Solubility in Salt-Containing Aqueous Solutions (Brines)
The amount of 5 g phosphate (phosphate mixture) is dissolved by stirring it into 75 g water and the amount of 20 g cooking salt is then added. The brine is analyzed to determine whether it is stable over a longer period of time (16 h), meaning no precipitation (excess solute) occurs.
*)Following the preparation, a cloudy solution results with low precipitation (excess solute) after 16 hours.
Evaluation:
+ = stable brine
− = precipitations/excess solutes occur
Solubility in Salt-Containing Aqueous Solutions (Brines) in a Traditional Sequence
The amount of 8 g phosphate (phosphate mixture) is dissolved by stirring it into 68 g water. Subsequently, the amount of 24 g cooking salt is added and the brine is then analyzed over a longer period of time (16 h) to determine whether it is stable, meaning no precipitations (excess solutes) occur.
Analysis:
+ = stable brine
− = precipitations/excess solutes occur
Solubility and Stability of Phosphates in Salt-Containing Aqueous Solutions (Brines) for Inverse Preparation of the Brine.
The amount of 22 g of cooking salt is dissolved by stirring it into 72.5 g water. Subsequently, the amount of 5.5 g phosphate (phosphate mixture) is stirred in. The brine is then analyzed over a longer period of time (16 h) to determine whether it is stable, meaning that no precipitations (excess solutes) occur.
*)Following preparation, a cloudy solution is obtained and after 16 h precipitations (excess solutes) occur.
Evaluation:
+ = stable brine
− = precipitations/excess solutes occur
Number | Date | Country | Kind |
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10163954.6-41 | Dec 2001 | DE | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/EP02/14272 | 12/14/2002 | WO | 4/24/2006 |