ISSN:
1750-3841
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
,
Process Engineering, Biotechnology, Nutrition Technology
Notes:
Dehydrated sweet potato flakes were prepared in a pilot plant by (1) peeling and comminuting fresh sweet potatoes; (2) heating sweet potato puree to 755°C and holding at that temperature to allow naturally present amylases to convert a certain proportion of the starch into sugars; (3) heating puree to 105°C to inactivate enzymes; (4) atmospheric drum drying and flaking; and (5) packing flakes in cans under N2 atmosphere Total monocarbonyls in fresh sweet potatoes generally increased with time of storage of the roots During processing of freshly dug sweet potatoes into dehydrated flakes, monocarbonyls increased as processing progressed. During processing of “cured,” and of up to 4-months' stored sweet potatoes the content of monocarbonyls peaked during conversion of starch to sugars, and decreased after heating to 105°C prior to drum drying. Levels of saturated aide hydes and of methyl ketones were also highest during amylolysis. During storage of the packaged flakes at 27°C for 128 days, total monocarbonyl content remained rather constant, while saturated aldehydes increased and methyl ketones decreased. At 45°C storage temperature, total monocarbonyls and saturated aldehydes showed a marked increase, while ketones decreased. There was a slight net increase in CO2 and O2 and a slight decrease in N2 in the gas present in cans of flakes stored for 1 yr at 24°C. After 12 months storage, 0.026% CO was found in the dehydrated sweet potato flake product monocarbonyls, particularly aldehydes, are probably a factor in off-flavor development during storage.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1365-2621.1976.tb00662.x
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