• Korean journal of food and cookery science
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• v.27 no.2
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• pp.73-81
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• 2011

Two kinds of steamed sweet potatoes were dried with mild hot air to improve quality, convenience and preference as a snack. Steamed sweet potatoes were dried at temperatures ranging from 35 to $65^{\circ}C$ for 12 hr, and moisture contents, colors, texture, and taste were evaluated. The lowest moisture content was 0.25% at $65^{\circ}C$. Color values (L, a, b and ${\Delta}E$) decreased with increasing drying temperature and drying time in both chestnut-sweet potatoes and pumpkin-sweet potatoes. Reducing sugars and soluble solids increased quickly at high drying temperatures. The highest hardness value for chestnut-sweet potatoes was $26.31\;kg_f /cm^2$when they were dried at $65^{\circ}C$ for 12 hrs. Springiness and cohesiveness were higher than those in chestnut-sweet potatoes. The highest taste score was for a dried chestnut-sweet potatoes at $55^{\circ}C$ for 6 hr and a dried pumpkin-sweet potatoes at 45 or $55^{\circ}C$ for 6 hr.

• Journal of the Korean Home Economics Association
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• v.42 no.1
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• pp.167-180
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• 2004

This study was carried out to investigate quality characteristics of chopped garlic stored at various temperature. Chopped garlic was stored at room temp.($25^{\circ}C$), refrigerator temp.($5^{\circ}C$) and frozen temp. ($-18^{\circ}C$) for 1, 2, 4, 8, 24, 48, 72 hours(room temp.) and 1, 3, 5, 7, 10, 15, 20, 30 days(refrigerator temp. and frozen temp.), respectively. Brown color, Hunter color value, vitamine C contents and flavor patterns by electronic noes of chopped garlic were measured. Fresh chopped garlic was used as control and garlic powder by hot air drying was used for comparisons. Brown color of chopped garlic increased with increasing storage time, and the intensity of that was reduced as following order such as chopped garlic stored at room temp., refrigerator temp. and frozen temp. Brown color of garlic powder was most dark amomg all the samples. The results of Hunter color value was consistent with then of brown color in chopped garlic, whereas those of garlic powder showed relatively low browning. Above results might be caused by the difference of measurement as only surface color was measured in Hunter color value unlike brown color. Vitamine C contents of chopped garlic decreased with increasing storage time, and in particular those stored at room temp. decreased markedly as retention of those stored at room temp. was 60％ of control after 1 day storage. Vitamine C retention of chopped garlic stored at refrigerator temp. was 78％ of control after 10 day storage and that stored at frozen temp. was 86％ of control after 30 day storage. At room temp., flavor pattern by electronic nose showed a difference between chopped garlic stored for 1hour and control, and showed occurrence of off odor after 1 day storage. Flavor pattern of garlic powder by electronic nose showed a mild flavor. Flavor patterns of chopped garlic stored at refrigerator temp. were similiar until 10 day storage, whereas those showed occurrence of volitile components after 15 day storage. Flavor patterns of chopped garlic stored at frozen temp. were similiar after 30 day storage, and especially those after 3 day storage were almost the same as control. Therefore it is desirable to store chopped garlic within 1 day at room temp. and within 10 days at refrigerator temp. And it is most desirable to store chopped garlic at frozen temp. as retention of quality characteristics was superior than other storage temp.