Abstract:

The distribution pattern of 3’,5’-cyclic adenosine monophosphate(cAMP) during the production
of concentrated apple juice was investigated. HPLC was employed to determine the cAMP content in
apple pomace left after juice extraction with water or aqueous ethanol and in concentrated apple juice. The
change trend of cAMP content in concentrated apple juice was analyzed as a function of dilution factor and
soluble solid content. Distribution coefficient (DCcAMP) was calculated to describe the distribution regularity
of cAMP. The result showed that cAMP contents in apple pomace, 70 °Brix concentrated apple juice, and
30 °Brix concentrated apple juice were (63.444 1 ± 2.323 6) μg/g, (58.611 3 ± 1.349 3) μg/mL and (12.018 3 ± 0.583 9) μg/mL,
respectively. An equation indicating cAMP content (y) as a function of soluble solid content (x) in concentrated apple juice
was established as follows: y = 0.808 5x − 1.218 5. Furthermore, the DCcAMP of 70 °Brix and 30 °Brix concentrated apple
juice were 92% and 19%, respectively. Thus, during the production of concentrated apple juice, cAMP preferred to exist in
apple pomace and could be enriched by the concentration process

Key words: apple juice concentrate, apple pomace, 3’,5’-cyclic adenosine monophosphate, HPLC