Abstract:
(Afra Ali, revised by Ted Stachon and Amy Lacy)
The
various experiments we conducted were done for the sole purpose of determining
whether Odwallaís Organic Orange Juice or Tropicana Orange Juice was closer in composition
to freshly squeezed orange juice. We anticipated that Odwallaís Organic Juice
would be closer in composition to that of freshly squeezed juice. We used
several methods to test this hypothesis. In looking for carbohydrates we used
Benedicts test to detect for reducing sugars, Bialís test looked for the
presence of furanoses, and the Iodine test to detect for starch. Paper
chromatography was performed to identify extracted pigments such as Carotene.
Salivary amylase was added to samples in controlled amounts for the purpose of
identifying the effect of an enzyme in orange juice.Ý Benedictís and Selivanoffís tests were again
used to determine the effect of the enzyme in the isolation of sugars.
ÝÝÝÝÝÝÝÝÝÝÝ The results from our experiments
verified our hypothesis. In Benedictís test, more red precipitate formed in
Odwallaís and fresh squeezed juices than in Tropicanaís. Bials test detected
furanose in both freshly squeezed and Odwallaís juices. Pentose-furanose was
found in Tropicana.Ý All three types of
orange juice had negative results in the iodine test for starch.Ý Similarly, the pigment tests were negative as
no visible pigments appeared in the solvent front.Ý Enzyme activity in Tropicanaís juice
decreased reaction time in sugar tests significantly more than in Odwallaís or
fresh squeezed juice. Therefore, these experiments demonstrate a similarity in
sugar content and enzyme activity between organic and fresh squeezed juice
compared to Tropicana brand.
<BACK