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Show TEST POTATOES FOR SUGARY CONTENT j Specialists of the United States Department De-partment of Agriculture have devised a simple method for selecting storage potatoes which will make good chips or French fries. A test for the soluble sugars in potatoes is the key that un-1 un-1 locks the secret of their culinary qualities, qual-ities, since an excessive amount of .these sugars produces a discoloration in French fries and chips and a sweetness sweet-ness in baked or boiled potatoes that is distasteful to some people. Potatoes stored at temperatures ranging from 32 degrees to 45 degrees de-grees F. accumulate certain soluble sugars as a result of the breakdown of starch. In general, the lower .the storage temperature the greater the amount of soluble sugars and the darker the color of the chips. To make the test, a sample from th center of the potato is placed in a yellow yel-low solution of picric acid and sodium, carbonate in a small test tube and heated over the flame of an alcohol lamp until it boils for one-half minute. Samples from potatoes that have not been stored at too low temperatures change the color of the solution to an orange yellow, but the excessive amount of sugars in tubers stored at low temperatures changes the color to a deep red or brown. This test has proved satisfactory' in selecting potatoes for chip making, French frying, baking, and under certain cer-tain conditions for boiling. It was designed de-signed especially for chip manufacturers, manufac-turers, who must have potatoes with a low content of soluble sugars. The test is so simple, since it involves only a small portable outfit, that it can be used by buyers for hotels and restaurants restaur-ants where there is demand for high-grade high-grade mealy oooked potatoes, free from a sweetish taste and discoloration. discolora-tion. o |