|MadSci Network: General Biology|
There may be several explanations for this puzzle.
First, let's start with the fact that potatoes are mainly starch. Starch is composed of a long chain of glucose (sugar) molecules. Cold temperatures convert some of this starch into sugar. Cooking with these afterwards should theoretically taste sweeter, however they would brown more quickly and can produce off-tastes. In fact, some may find it less pleasant tasting, because freezing can cause some loss of flavor due to the damaging effect on the vegetable's cells. Often, the cell's can be broken and disrupted, leaching out some flavor compounds. It is generally not recommended to store potatoes for these reasons in temperatures colder than 45 degrees fahrenheit, or expose them to light. (More on that later).
On the other hand, improper storage can cause significant deterioration
in the taste and quality of vegetables.
Moisture loss, texture loss, and loss of flavor are all possible consequences of storing fresh food too long or improperly. Storing too long can cause overripeness and shrinkle them.
Perhaps then, your frozen food could taste better.
Furthermore, fresh potatoes are susceptible to the development of chlorophyll, and parallel to that, solanine - (a toxic bitter alkaloid), if improperly stored. A main contributor of this phenomenon is light.
There then, is a little science about the potato.
Hope that cleared up some of its mysteries.
Reference: What to Eat - Marion Nestle
Foods that Harm - Foods that Heal. (Reader's Digest).
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