The researchers analyzed five orange products: fresh unprocessed orange segments, homogenized (pureed) orange segments, freshly squeezed juice, pasteurized juice, and flash-pasteurized juice.
They found that levels of vitamin C and carotenoids were basically the same in the juice and the unprocessed fruit, while levels of flavonoids were significantly lower.
The researchers then used a test tube model designed to mimic digestion to evaluate the bioaccessibility—how easily the body can absorb the nutrient. Interestingly, the researchers found that much more of the carotenoids and flavonoids were released from the orange juice than from the fruit slices or puree. In fact, carotenoid release went up from nearly 10.8% in the fruit to 28.3% in the fresh juice, and up to 39.5% in the pasteurized juice. Meanwhile, flavonoids were boosted nearly five-fold to 96.5% in juice compared to fruit.