Studies show that nutritional value is lost when raw fruit is processed.
Is drinking 100% Juice as nutritionally beneficial as eating the raw fruit? Several studies have been conducted to answer this question. In 2005 a German study entitled Processing Strawberries to Different Products Alters Contents of Vitamin C, Total Phenolics, Total Anthocyanins, and Antioxidant Capacity was published to answer this question. This study, like similar studies, found that nutritional content was lost as the raw fruit (in this study strawberries) was processed.
The researchers began by determining the amount the amount of vitamin C, phenolics and anthocyanins in raw strawberries. Raw strawberries were then processed into juice, nectar, wine and puree using various procedures. After each procedure the nutritional content retained was determined. The researchers found that pasteurization and fermentation resulted in significant reductions in nutritional value. Pasteurized juice was determined to retain just 36.0% and 35.6% of the raw strawberries' vitamin C and phenolics, respectively. Conversely, press-made juice was shown to retain 75.5% vitamin C and 61.0% phenolics. The procedures used to get to the end product showed large disparities in their respective reductions in nutritional content. Consider wine (strawberry wine anyone?), which can be produced from mash or from juice. Vitamin C content relative to the original raw strawberries was around 35% regardless of whether or not it came from mash or juice. However, phenolics relative to the raw strawberry was 62.6% in wine made from strawberry mash and only 46.9% in wine made from strawberry juice.
These results have beed confirmed in two separate studies appearing in the Journal of Agriculture and Food Chemistry, both in 2008. Their titles are Influence of Processing on Quality Parameters of Strawberries and Processing and Storage Effects on Monomeric Anthocyans, Percent Polymeric Color, and Antioxidant Capacity of Processed Blackberry Products.
In conclusion, take the whole fruit!