JPS6332426B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention generally provides naturally colored vitamin C
The invention relates to fortified food products, and in particular to such foods containing anthocyanin or anthocyanidin pigments and bioactive vitamin C. Since the discovery in the mid-19th century that edible oranges and lemons effectively treat scurvy,
Vitamin C has been used more or less continuously as a dietary supplement. Shortly after the isolation of naturally occurring L-ascorbic acid (ascorbic acid), an efficient method for its synthesis was developed. These developments, along with the recognition that its presence in food is essential for human health, have encouraged food manufacturers to add bioactive sources of vitamin C to their foods, or to use naturally occurring sources of vitamin C. Attempts have been made to increase the concentration of However, these attempts have been unsuccessful in a significant number of applications as a result of ascorbic acid's well-known autooxidative instability or its reactivity with other dietary components. An example of its reactivity towards other food ingredients occurs when ascorbic acid is present in an aqueous mixture that also contains anthocyanin pigments. The incompatibility of anthocyanin-based pigments, i.e. anthocyanins or anthocyanidins, with ascorbic acid has been reported in the literature [Sondheimer, E. and Kertesz, Z.
I., Food Res . , 17 , 288 (1952); Starr, M.S.
and Francis, F.J., Food Technol . twenty two ,
1293 (1968)] is a well-established fact. When both ascorbic acid and anthocyanin pigments are present in solution, a chemical reaction occurs resulting in bleaching of the pigment and decomposition of the ascorbic acid. The half-life of anthocyanin pigments at PH3 and room temperature can be reduced by a factor of as much as 10 ppm for a beverage containing 10 ppm anthocyanidins and 600 ppm ascorbic acid. This decomposition rate was found to increase by increasing temperature and light exposure. Although the mechanism of the bleaching reaction between ascorbic acid and anthocyanin pigments has not been finally clarified,
At least two mechanistic theories have been proposed to explain this phenomenon. The first mechanistic theory postulates a redox pathway involving both ascorbic acid and oxygen. Publication “Oxygen and Ascorbic Acid Effect on the
Relative Stability of Four Anthocyanin
Pigments in Cranberry Juice” [Starr, MS and Francis, FJ, Food Technology , 22 ,
1293-95 (1968)], the authors used the 1943 discovery that increasing the upper air space in bottles of strawberry juice containing anthocyanin pigments increased the decomposition of this pigment to reduce the amount of ascorbic acid in anthocyanin pigments. I realized that oxygen is involved in bleaching. A 1956 report discloses that oxygen increased the rate and extent of discoloration of red anthocyanin pigments. With this Starr
The Francis publication further describes previous work on ascorbic acid bleaching of anthocyanins in the presence of oxygen, which theorizes that a reactive intermediate is formed from an initial oxygen-ascorbic acid reaction. Supported (the intermediate is likely hydrogen peroxide or a free radical species). This intermediate subsequently reacts with the anthocyanin pigment.
From their original research reported in this publication,
Starr and Francis disclose that bleaching is increased by increasing the concentration of oxygen or ascorbic acid. A more recent publication by Shirkhande and Francis [Effect of Flavonols on Ascorbic Acid]
and Anthocyanin Stability in Model
Systems, J.Food Sci., 39 , 904 (1974)], the authors present the theory that hydrogen peroxide (formed from oxygen and ascorbic acid via a liberatory mechanism) is a reactive intermediate in the bleaching of anthocyanins. and the fact that flavanols retard the autoxidation of ascorbic acid. The authors also note the previously published observation that the simultaneous presence of both flavanols and andocyanins in ascorbic acid solutions appears to prevent ascorbic acid oxidation. In the results of their study reported in this publication,
Addition of the flavanol antioxidant quercetin or quercitrin to a model system containing dissolved oxygen, ascorbic acid, and the four anthocyanins found in climbing berries
It has been shown that both the oxidation of ascorbic acid and the bleaching of anthocyanins are retarded.
The authors conclude that these results indicate that the ascorbic acid reaction involves a first step of the oxygen-ascorbic acid reaction that generates hydrogen peroxide or a free radical species as a reactive intermediate, followed by a second step of reactive intermediate-anthocyanin bleaching. Consistent with an acid-anthocyanin bleaching mechanism. A second mechanistic theory for ascorbic acid bleaching of anthocyanin pigments was proposed by Jurd [“The Chemistry of Plant Pigments”]
“Some Advances in the Chemistry of
Anthocyanin−Type Plant Pigments”, pp.123
−42, Co. O. Chichester, Ed., Academic
Press, NY, 1972 and references therein].
According to this theory, the bleaching reaction between these two species occurs as a result of a parent reaction with ascorbic acid at the 4-position of the pigment. In addition to the tendency of ascorbic acid to bleach anthocyanin and anthocyanidin pigments, the tendency of acidic aqueous solutions to autoxidize in acidic aqueous solutions in the presence of air has long been known. This process of autoxidation is carried out by copper() ions and by the enzyme ascorbate oxidase [Dawson, CR,
Ann.NYAcad.Sci., 88, 353 (1960)] and by light [McAlpine, RD, et al., Can.J.
Chem., 51, 1682 (1973)] is known to be accelerated. Because of this phenomenon of autoxidation, the rate of autoxidation is increased by light and other factors, making it possible to produce derivatives of ascorbic acid that retain some in vivo vitamin C activity but do not exhibit this autoxidative degradation. Some research has been done attempting to synthesize. As a result of these efforts, derivatives of ascorbic acid substituted at the enolic OH function at the C ₂ and/or C ₃ positions have been developed as vitamin C
This family is able to resist autoxidation due to blocking of the ene-diol functionality. Many of these derivatives, particularly ascorbyl esters at _C2 and/or _C3 , were tested on scurvy guinea pigs and were found to retain vitamin C potency equivalent to unsubstituted ascorbic acid. Such retention of the potency of vitamin C is due to 2-O-phosphate [Imai, Y.et Al.,
Jap.J.Pharmacol., 17, 317, (1967)] and 2
-O-benzoate [Ibid., 17 , 330, (1967)]
in guinea pigs with scurvy, and 2
-O-sulfate on scurvy rainbow trout [Halver, JE, et al., Ann NYAcad.Sci.,
258, 81 (1975)] and monkeys [Baker, EM, et al.
et al., Ann NYAcad.Sci., 258 , 72 (1975)]. In addition to the aforementioned ascorbyl esters, C ₃ and/or C ₂ O-alkylated derivatives of ascorbic acid exhibit both stability against autoxidation and in vivo vitamin C activity, yet can be active at low concentrations. revealed. For example, 3-O-methylascorbic acid was found to provide antiscurvy effects in guinea pigs at 1/50th the level of vitamin C when administered orally [Gould, et al.
BSet al., Arch.Biochem., 23 , 205 (1949)]. Despite the discovery of such non-autooxidizing vitamin C derivatives, and despite the constantly increasing interest in providing foods containing bioactive ascorbic acid and anthocyanins or anthocyanidin pigments, this The development of such foods has been hampered by the incompatibility between these natural contents and vitamin C, which may be due to nucleophilic substitution at the 4-position of anthocyanin pigments or to ascorbic acid, oxygen and It has been thought that it arises from an oxidation-reduction reaction involving anthocyanin pigments. Now, it has been found that according to the present invention, it is possible to produce a color-stable food composition containing both anthocyanin pigments and biologically effective vitamin C. Such foods are dry mixtures that are compatible with mixing with water,
Beverage syrups or mixtures compatible with water dilution;
Alternatively, diluted beverages can be included. Such color-stable, bioactive, vitamin C-enriched food composition products of the type in which the color is provided by one or more anthocyanin-based pigments also include:
It has been found that it can be prepared by a process consisting of combining a food base, an anthocyanin pigment, and ascorbic acid block-linked in one or both of the enolic OH functions. Examples of such blocking substituents are -R, -
SO ₃ H, -PO ₃ H ₂ or [Formula], where R is an aliphatic residue having 1 to 10 carbon atoms. In order to provide a thorough understanding of the present invention, the following description is provided. It has been found that certain ascorbic acid derivatives in which the enediol function is block-substituted on one or both of the enolic OH functions do not bleach anthocyanins or anthocyanidins as quickly as unsubstituted ascorbic acid. It was also found that this effect is restricted to a certain group of substituents on the enolic functionality. Some block substituted ascorbic acid species are shown below. TABLE As is well known to those skilled in the art, ascorbic acid and its derivatives that retain one or more acidic hydrogens can be reacted with a base to produce ascorbate and water. In this regard, the inorganic esters of sulfate and phosphate shown above were obtained and used in the following experiments in the form of dibasic salts of barium and magnesium, respectively, while the remaining species were used in the form of the free acid. did. Regardless of whether the free acid or salt form of any particular species is used, other forms of the species are fully equivalents and behave in substantially similar ways;
It is believed that the selected form has substantially the same effect. Some of the O-alkylated and inorganic ester derivatives of ascorbic acid shown in the table were tested in terms of their relative bleaching power for acidic aqueous solutions of a representative anthocyanidin, namely apigenidin chloride, according to the draft described in the Examples. Tested. EXAMPLE Bleaching of anthocyanidins with ascorbic acid derivatives 10 mg apigenidin chloride, 1.92 g citric acid and 250 mg sodium benzoate were transferred to a 1 volume flask, dissolved in deionized water and diluted to the mark. A 100 ml aliquot of the resulting solution was
Pipetted into seven 100 ml flasks, each containing the following amount of the seeds indicated above: 60 mg.
of ascorbic acid (reference number 1); 65 mg of 3-O
- methylascorbic acid (reference number 2); 70 mg of 2,3-O-dimethylascorbic acid (reference number 3); 137 mg of ascorbic acid 2-O-sulfate (as dibasic barium salt) (reference number 4);
100 mg ascorbic acid 2-O-phosphate (dibasic magnesium salt) (reference number 5); 74 mg
of 5,6-isopropylidene ascorbic acid (reference number 9); and 84 mg of 2,3-O-dimethyl 5,6-isopropylidene ascorbic acid (reference number 10). Each flask was capped and stored at ambient temperature and light. At varying intervals, small aliquots of each of the seven test solutions were withdrawn from the flask and their absorption at 470 nm was measured on a Beckman 25 UV/VIS spectrophotometer using a quartz cell and a deionized water reference. Divide the raw absorption data by the absorption at time zero for each solution and multiply by 100 to get the “% color retention”
I got the value for . The results are shown in the table. [Table] Species by number.

Claims (1)

[Claims] 1. Food-based, anthocyanin-based pigment and at least one block-substituted enolic
A food composition comprising an ascorbic acid derivative having OH functionality. 2 Food-based and pigments selected from the group consisting of anthocyanins, anthocyanidins and combinations thereof, and the formula Here, one of R〓 and R〓 is −R, −SO ₃ H, −SO ₃
-, -PO ₃ H ₂ , -PO ₃ H- and [Formula], and the other of R〓 and R〓 is -H, -R,
selected from the group consisting of -SO ₃ H, -SO ₃ -, -PO ₃ H ₂ , -PO ₃ H- and [Formula], and R is an aliphatic organic residue having 1 to 10 carbon atoms; The food composition according to claim 1, comprising an ascorbic acid derivative or a non-toxic salt thereof. 3. The food composition of claim 2, wherein the food composition is dry. 4. A food composition according to claim 2, wherein said food composition comprises a concentrated syrup or concentrate. 5. The food composition of claim 2, wherein the food composition comprises a diluted beverage. 6 One of R〓 and R〓 is −SO ₃ H, −SO ₃ −, −
is a substituent selected from the group consisting of PO ₃ H ₂ and -PO ₃ H ^- , and the other of R〓 and R〓 is -
The food composition according to claim 2 _, wherein the substituent is selected from the group consisting of H, _-SO3H , _-SO3- ^, _-PO3H2 ^and _-PO3H- . 7 One of R〓 and R〓 is selected from the group consisting of [formula], and the other of R〓 and R〓 is selected from the group consisting of -H and [formula], where R has 1 to 10 carbon atoms. 7. A food composition according to claim 6, which is an aliphatic organic residue of. 8 The ascorbic acid derivative is ascorbic acid 2
7. A food composition according to claim 6, comprising -O-phosphate or a non-toxic salt thereof.