Vitamin C Content of Orange-Crush Beverage ELIZABETH M. KOCHAND F. C. KOCH Department of Physiological Chemistry and Pharmacology, University of Chicago, Chicago, Ill.
HE increasing popularity of commercial fruit-juice drinks is resulting in the consumption in this form of considerable amounts of fruit, especially of the citrus variety. The peculiar advantages of these fruits as sources of vitamins make it important t o know whether the processes of preparation, mixing, and storage are such as to retain in the finished product all of the original vitamin potency of the fresh juice. This investigation of Orange Crush is reported as a contribution to these questions. In the preparation of Orange Crush, freshly gathered oranges are used. They are subjected to such pressure that a thick mixture of the pulp and some of the skin is forced out with the juice. To this mixture of juice and pulp are added sugar, lemon citric acid, small amounts of preservative, and a color, consisting of a mixture of Sunset Yellow F. C. F. and No. 150 (85) Orange I. The resulting Crush sirup is stored in bulk a t refrigerator temperature until it is to be diluted for the finished drink. Carbonated or plain tap water is used for the final dilution. It is added to the sirup by the retail dealer who is instructed to prepare not more than a week’s supply at one time. The following materials, freshly prepared from one lot of oranges, were supplied:
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1. Orange juice, unstrained, pressed from freshly gathered oranges. 2. Crush sirup, made from 1 by the addition of sugar, lemon citric acid, and small amounts of sodium benzoate and color. 3. Bottled Orange Crush, prepared by dilution of the sirup with carbonated tap water. 4 . Bottled carbonated tap water and distilled water.
The antiscorbutic potency of these orange preparations was compared with equivalent amounts of the juice of some of these same oranges expressed daily.
EXPERIMENTAL PROCEDURE The diet first used, consisting of oatmeal, autoclaved hay, and 20 cc. of whole milk daily, was one previously employed in this laboratory. Preliminary feeding experiments were run to determine how much of the Crush sirup and dilute Orange Crush the guinea pigs could be induced to consume. It was a simple matter to give the orange juice, unstrained, in 5-cc. amounts mixed with the liquid milk, but the Crush sirup with the added citric acid curdled the milk, making a thick mixture which was left almost untouched. Of the dilute Orange Crush, pigs weighing 300 to 350 grams took readily 21 cc., the equivalent of 1 cc. of original orange juice unstrained. Some of the pigs would drink as much as 30 to 40 cc., but these results could not be relied upon for all of the experimental animals. In view of these preliminary findings, it was obvious that the total volume of liquid must be kept within 20 to 25 cc. Dried whole milk was therefore substituted for the liquid milk and mixed thoroughly with the oatmeal. The various orangejuice preparations were diluted with water to the desired volume-21 cc. total. Seven groups of four pigs each were given daily the following preparations: 1 and 2 cc. of freshly
expressed orange juice; 1 and 2 cc. of the prepared orange juice, unstrained; 1.7 and 3.4 cc. of the Crush sirup (the equivalents of 1and 2 cc. of the orange juice, unstrained, from which the sirup was made); and 21 cc. of the bottled Orange Crush the equivalent of 1 cc. of orange juice, unstrained or of 1.7 cc. of Crush sirup. Another group was given the straight scorbutic diet with water only. Each dosage was diluted to 21 cc. before feeding. The diluted fruit juice was ordinarily consumed within 4 to 5 hours after feeding. After the consumption of the diluted juice, fresh water was placed in the cage. Three months later these experiments were repeated to ascertain what loss of vitamin C had occurred during storage of the fruit and juice preparations a t refrigerator temperature. A portion of the orange juice, unstrained, was also frozen within 48 hours after i t was expressed and kept in that condition for three months.
RESULTS Some of the pigs which developed acute scurvy were killed on the twenty-eighth day of the experimental period. Others were permitted to live until death occurred some time between the twenty-eighth and the forty-eighth days. The animals which lived beyond 36 days were receiving small amounts of vitamin C. The pigs to which orange juice, unstrained, and Crush sirup were administered, were killed a t intervals between the twenty-eighth and the forty-eighth days. The usual autopsy findings were supplemented by histological examination of the teeth. I n the first series of experiments it was observed that, by both methods of measuring antiscorbutic potency, the feeding of amounts of Crush sirup equivalent to 1 and 2 cc. of orange juice, unstrained, daily (i.e., 1.7 and 3.4 cc., respectively, of the Crush sirup stored in the refrigerator) gave results which were as good or even slightly better than those obtained by feeding 1 and 2 cc. of freshly expressed orange juice. It was surprising then to find that the orange juice, unstrained, from which the crush sirup was made was much less efficacious. Animals receiving as much as 5 cc. of orange juice, unstrained, daily were distinctly scorbutic. In 2-cc. daily dosages the degree of prevention was so slight that it could be detected only by histological examination of the teeth. The repetition of these tests 3 months later with oranges, with orange juice, unstrained, and with Crush sirup which had been stored a t refrigerator temperature during that period, gave further confirmation of the early results. The oranges and the Crush sirup showed no detectable loss of their vitamin C potencies so far as could be determined by tooth histology. The orange juice unstrained, on the other hand, showed no antiscorbutic action in the dosages fed. The same loss of antiscorbutic potency was observed in the orange juice, unstrained, which had been frozen within 48 hours after i t was expressed and kept in that condition for 3 months. In view of these observations with orange juice, unstrained, it was not surprising to find that the diluted Orange Crush which was bottled and stored in the refrigerator for 50 days
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before the close of the experiment, showed no detectable antiscorbutic potency in the dosage fed. The pigs in this group were all dead of scurvy by the thirty-ninth day of the experimental diet. Whereas this is a few days beyond the life period of the control scurvy animals, the tooth histology showed no evidence of prevention. These results demonstrated first that the fruit itself stored at refrigerator temperature retains its vitamin C content a t least for 3 months; second, that the orange juice, unstrained, expressed from these oranges, loses its antiscorbutic potency so rapidly that a test which extends over 4 weeks demonstrates that loss, and that at the end of 3 months the destruction appears to be practically complete; third, that a heavy Crush sirup made from this orange juice, unstrained, by adding sugar and preservative and acidifying with lemon citric acid retains the original vitamin C as satisfactorily as does the fruit itself during refrigerator storage for 3 months; and fourth, that this Crush sirup, when diluted to twelve volumes with carbonated water again loses its antiscorbutic action so rapidly that storage in that condition for 4 to 5 weeks is not feasible. Since it is in this final diluted form that Orange Crush is dispensed to the public, it is highly important to know the rate of destruction of vitamin C under these conditions. The retailer is required to dilute and bottle Orange Crush weekly, Ten to fourteen days should, therefore, be the maximum lapse of time between dilution and consumption of this product. A final set of experiments was run in which one group of pigs was given 1 cc. of orange juice. equivalent per pig of a new supply of freshly prepared Crush sirup diluted daily. Another group of animals was given the same amount of Crush sirup which had been diluted, bottled, and allowed to stand in the refrigerator 10 days before feeding. A control scurvy group was run parallel to these. By the thirty-fifth day one of the scurvy pigs was dead. The other had lost 135 grams in weight and had swollen tender joints, red gums, and loose yellow teeth. The autopsy findings were those of advanced scurvy. The pigs in the other two groups were either holding their maximum weight or gaining slowly. They were fairly strong and active, and their fur was smooth and well-kept. The autopsy findings were those of mild scurvy. The antiscorbutic potency of this sample of Crush sirup was undoubtedly higher than that of the original lot supplied for the earlier experiments reported above. The important consideration in this experiment, however, was that the 10-day storage period at refrigerator temperature did not produce sufficient deterioration of the antiscorbutic potency to be detected by such biological tests. It must be borne in mind, nevertheless, that in making this dilution there was a minimum of exposure to air and room temperature. These observations tend to the conclusion that the preservation of antiscorbutic activity in the Crush sirup is due to the high acidity and possibly to the sugar content, and that the loss of potency following dilution is the result of decreased protective action and takes place gradually. It may be that traces of chlorine or other constituents of tap water have slight destructive action. These factors appear to be insignificant, however, for it apparently makes no difference whether the dilution is made with ordinary tap water, carbonated water, or carbonated distilled water. Remove1 of carbon dioxide from the diluted sirup by suction was of no significance. Since the orange juice, unstrained, from which the Crush sirup is prepared contains appreciable amounts of pulp and skin as compared with the hand-expressed orange juice, it seemed logical to expect somewhat less vitamin C potency in the Crush sirup than in the freshly expressed juice. This was not the case however; in fact, the difference, if any, was in favor of the Crush sirup. This result raised the question of whether the added citric acid, which is prepared from lemons,
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does not carry some vitamin C. Samples of citric acid prepared from lemons and also by fermentation were secured and added to a sugar solution so that 20 cc., the daily intake, contained 0.2 gram of acid. This amount was four times the intake of citric acid when 1.7 cc. of Crush sirup were administered. However, in neither case did the citric acid solution have the slightest effect in delaying the onset of acute scurvy. Obviously then, the vitamin C of the Crush sirup is derived entirely from the orange juice, unstrained, and probably is preserved by the addition of citric acid, or in part, perhaps, by the high sugar content. I n 3 months there was no apparent loss of this potency unless the Crush sirup wa,s diluted again to a low acidity. CONCLUSIONS Esperiments conducted to determine whether the commercial orange-juice drink called Orange Crush retains the vitamin C originally present in the fruit have resulted in the following conclusions: 1. The orange juice, unstrained, commercially expressed from freshly gathered oranges was as potent in vitamin C as ordinary hand-expressed juice. 2. When stored either frozen or at refrigerator temperature in this form, it lost that potency so rapidly that the loss wat. marked during a 4-week test period, and practically complete at the end of 3 months. 3. When this orange juice, unstrained, was diluted to 1.7 times its volume of Crush sirup by the addition of sugar. lemon citric acid, and a small amount of preservative and coloring, it retained the original vitamin C practically undiminished for a period of 3 months. 4. The antiscorbutic potency of the Crush Sirup was not a result of any vitamin having been added with the citric acid. The vitamin of the original juice appeared to be preeerved by the high acidity and possibly high sugar content of the sirup. The preservative action of the acid sirup is of academic and commercial interest. 5. When the final beverage, Orange Crush, was prepared commercially from the crush sirup by diluting 12.3 times with carbonated water, the resulting product gradually lost its vitamin C potency. 6. When the same dilution was made in the laboratory with a minimum opportunity for exposure to air and room temperature, and the diluted bottled product was stored in the refrigerator 10 days before feeding, there was no detectable loss of antiscorbutic potency. 7 . The results show that if the final dilution of Crush sirup is done in accordance with the precautions stipulated by the company and dispensed within 10 days, the final bottled Orange Crush retains essentially the original vitamin C activity; that is, it contains the vitamin C from 1 cc. of orange juice per 21 cc. of Orange Crush. It appears, therefore, that a maximum interval of 10 to 14 days between dilution and consumption of the finished product assures the presence of antiscorbutic potency in Orange Crush as it is dispensed to the public. ACKNOWLEDGMENT The authors wish to express to R. R. Bensley, William Bloom, and I. Shouer, of the department of anatomy, University of Chicago, appreciation for their generous assistance in preparing and interpreting the various tooth sections. RECEIVED October 19, 1931. The expense of this investigation wan i n part borne by the Orange Crush Company through the cnt~rteayof W. D. Boat.
