Thursday, April 2, 2009


One out of 5 calories consumed by humans comes through liquid foods that include beverages also, highlighting the crucial importance of water for life sustenance. Water needs vary from person to person, the nature of foods consumed and the environmental conditions. Too much water intake can also cause water 'intoxication' resulting in excess sodium drain and consequent effect on electrolyte balance. Juices extracted from fruits and vegetables are major carriers of water though they also contain many valuable nutrients. Conventionally juice from any fruit is made by removing so called inedible portions like peel and seeds, thermal inactivation of native enzymes, coarse and fine filtration steps, clarification by pectinase enzyme in some cases and sterilization. The juice is packed aseptically or canned or concentrated and frozen for marketing. Sugar preserved products like squashes and syrups are made by comparatively inexpensive process. Ready To Serve Beverages (RTS) made with fruit pulp, water, sugar and added flavors and citric acid are packed in returnable glass bottles or tetra pack cartons. Nutritionally RTS beverages are just a source of sugar with very low nutrient density as the fruit pulp content can be as low as 10% in many cases. Why such products with almost empty calories are permitted, targeted especially against younger consumers, is beyond one's comprehension. Why do we blame soft drink industry for doing precisely the same through their syrup based carbonated drinks?
Advent of Tetrapack technology has encouraged a couple of processors to introduce 100% juices from fruits like orange, guava etc but due to cost factor they are yet to take off. Considering that the yield of juice from a fruit like orange is less than 50%, the final cost of the end product is bound to be on the higher side, especially when the processors have no control on the raw material price as the fruits are sourced at prevailing wholesale market prices. There is a possibility of reducing the prices if yield can be increased, thus diluting the cost component from the fruit in the final production cost. Food technology must take the blame for playing to the illogical demands of consumers when it comes to juice products. Use of pectinase to clarify fruit juices is a classical example of this trend. Fruit juices are invariably made to look thin or clear and consumer is under the mistaken impression that clear juices are better ignoring the reality that the suspended insoluble matter removed during clarification is rich in dietary fiber and many phytonutrients. There is an urgent need to revisit the juice making technology as it is practiced to day to make the products more health friendly.
Comminuted fruit juices, containing almost all the goodness present in the whole fruit, can be made adapting the existing technology. Whole fruit is crushed and comminuted to reduce the particle size of the pulp to about 100-500 micron levels and the yield can be as high as 97% in a fruit like orange or grapefruit, only residue rejected being the seeds. The product so obtained is a highly concentrated beverage base which can be diluted to the desired taste threshold to get RTS drinks. Major advantages for such a product include lower cost of the finished product and significantly higher health benefits. Probably other fruits like apple, guava, plums, peaches, etc also could be processed into comminuted beverage base for preparing more healthy RTS drinks. The process for comminuted beverage type of products involves selecting fully ripe fruits, their washing, steaming, cutting into pieces, mixing with sugar solution, blending, pulping and making a homogeneous product which can then be formulated into RTS drinks.
A fruit like orange has more than 170 different phytonutrients and 60 flavonoids, all considered good for protection against diseases like low blood pressure, high cholesterol, inflammation, many types of cancers, heart disease, strokes, cardiac arrhythmia, arthritis, asthma, Alzheimer's, Parkinson's, Diabetes and Chrohn's disease. Orange fruit has two distinct parts, Pericarp consisting of Flavedo, the outer colored peel layer and Albedo, the inner white portion of the peel and Endocarp made of segments and juice vesicles containing the juice. Pericarp, which is normally thrown away is the repository of essential oils rich in terpenes and oxygenated terpenes, bicyclic terpenes, sesquiterpenes, aliphatic compounds, aromatic hydrocarbons, esters containing nitrogen, paraffin wax, steroids, triterpenes, fatty acids, coumarins, psoralins, flavones such as hesperetin and naringenin, anthocyanins, hydroxy cinnamic acid, polyphenols, pigments, carotenoids, chloroplasts, pectin, fiber etc. Gallic acid, a polyphenol and hesperidin, a polymethoxylated flavone are considered highly beneficial in maintaining good health if regularly consumed. These phytonutrients in presence of Vitamin C, contained in the juice exert high antioxidant effect at the cellular level. 
Citrus fruits like orange, lemon and grapefruit typically yield 22-38% peel, 34-78% pulp and 22-51% juice. Presence of limonin does impart some bitterness in the concentrated base but this is diluted when RTS drinks are formulated and masked in presence of sugar. The superior flavor due to higher content of oxygenated terpenes in comminuted juice, as compared to thin and clear juices is another feature deserving consideration. There is every justification for encouraging manufacture and consumption of comminuted fruit drinks considering the enormous health benefits such products can confer on the consumers.  

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