You may know that freshly picked corn is sweeter than corn that has been picked

Question

You may know that freshly picked corn is sweeter than corn that has been picked and stored for several days. This is because the stored corn contains less sugar than the freshly picked corn. About half of the sugar in fresh-picked corn has been converted into starch only one day after the corn can be preserved by "blanching" the ears- dipping the ears of corn into boiling water for a few minutes, then cooling them in cold water. Corn that has been blanched and then frozen maintains its sweetness for a long time.Propose a biochemical reason why blanching corn maintains its sweetness.

Explanation / Answer

The sweet taste of freshly picked corn (maize) is due to the high level of sugar in the kernels. Store-bought corn (several days after picking) is not as sweet because about 50% of the free sugar is converted into starch within one day of picking. To preserve the sweet-ness of fresh corn, the husked ears can be immersed in boiling water for a few minutes ("blanched") then cooled in cold water. Corn processed in this way and stored in a freezer maintains its sweetness. Thisis because after an ear of corn has been removed from the plant, the enzyme-catalyzed conver-sion of sugar to starch continues. Inactivation of these enzymes slows down the conversion to an imperceptible rate.

One of the simplest techniques for inactivating enzymes is heat denaturation. Freezing the corn lowers any remaining enzyme activity to an insignificant leveL

Related Questions

Navigate

• Browse (All)
• Browse Y
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.