Way back in late nineteen eighties, GOI was contemplating making addition of fruit juice mandatory to all soft drinks, ostensibly to find outlet for the products from fruit processing industry. Juice consumption was very low in the country while soft drink industry was churning out popular products like cola beverages and artificially flavored fizz drinks. However the proposal never saw the light of the day, probably because of the clout the fizz drink industry enjoyed during that period. Though there were technical problems in carbonating fruit juices containing particulate materials like fine fiber, it was not insurmountable provided there was a will to do it. Besides incorporation of juice at10% level hardly makes any difference as far as nutritive value of the end product was concerned. Fortunately fruit juice industry could establish its credentials subsequently thanks to the advent of tetra pack technology which could preserve the juice without exposing to high temperatures for long time necessary for sterilization or without use of chemical preservatives. To day 100% fruit juices are available in tetra pack, though at a cost much higher than that of soft drinks.
Effervescent drinks provide the bubbly feeling because of the escape of CO2 from an aqueous solution. Natural carbonation occurs due to aerobic fermentation by yeast in products like beer and sparkling wine while forced carbonation is achieved by infusing gaseous CO2 at low temperatures under high pressure. Carbonation is supposed to give bite to any drink whereas the fizzy taste is contributed by dilute carbonic acid inducing a slight burning sensation liked by many. CO2 solubility in water increases with pressure, lowering of temperature to near zero degree centigrade, increasing the pH and decreases with concentration of ionic solutes like sodium chloride. Presence of organic compounds may increase or decrease the CO2 concentration. At 0 C 0.334 gm of CO2 dissolves in water while the corresponding figure decreases to 0.287 gm at 4 C, 0.2492 gm at 8 C at atmospheric pressure. The solubility increase with pressure and soda and fizzy drinks are made by saturating refrigerated water with CO2 under pressure before mixing with sweetening and other flavor ingredients.
Carbonation of milk is an unthinkable proposition till recently and many believe that CO2 and milk are incompatible. But application of basic food science principles and use of appropriate equipment can give a milk beverage containing CO2 at levels that can be enjoyable to many consumers. It is also known that presence of suspended solids can hinder CO2 retention as they act as nucleus for coalescing the unstable gas bubbles and casein present in milk tends to get precipitated in presence of CO2, especially at higher temperatures. It is not that milk is never carbonated but the purpose is to increase the shelf life of fluid milk and other milk based products by at least 50%, though this is not a widely followed practice in the industry. Reducing the particle size of suspended milk solids to sub-micron levels through high end homogenizers, the coalescing effect of CO2 can be significantly retarded and under pressure the product can be stabilized. How such a product will be accepted by the consumer is another matter that needs to be explored by the industry.
The reported soft launch of a designer drink based on skimmed milk and containing CO2 in New York by the beverage giant Coca Cola may yet enable dairy industry to stimulate milk consumption amongst youngsters, weaning them away from the 'nutrient shallow'' synthetic soft drinks. Selling at a stiff price of almost $ 4 a bottle
the new product named 'Vio' is being offered in different flavors like peach, mango, berry, citrus, tropical and colada. The process involves mixing of skimmed milk with sparkling water flavored with fruit and cane sugar sweetener. Good milk flavor, fruity aroma and creamy body provide the product a distinct personality of its own, not found in many established beverages. The USP of the product is that the sweet taste is discernible only after the entire bottle is consumed, delaying the satiety feeling. It is time for Indian Dairy industry to think on similar lines, if milk consumption is to be boosted in the country where the successful 'operation flood' program has created a milk surplus.