• Food Science and Preservation
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• v.5 no.2
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• pp.172-176
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• 1998

This study was conducted to develop purees from pumpkin and sweet-pumpkin. Soluble solids in pumpkins were increased as heating time increase. The maximum yield of puree from sweet-pumpkin marked 78.2% when in prepared at 121$^{\circ}C$ for 60 minutes heating, but puree from pumpkin was 53.2% at 121$^{\circ}C$ for 40 minutes heating. Soluble solid and yield of pumpkin purees were increased with enzyme treatment. but viscosity was deceased remarkably. Hunter's a and b values of puree from sweet-pumpkin were higher than puree from pumpkin, and it was considered due to higher content of carotenoid. Organoleptic qualities of puree from pumpkin and sweet-pumpkin were investigated by 5-point scale and the most effective heating time was 40 minutes at 121$^{\circ}C$.

• The Korean Journal of Food And Nutrition
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• v.26 no.3
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• pp.565-572
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• 2013

This study was performed to optimize the processing conditions and to select the optimum species for colored sweet potato chips (Shinjami, Juhwangmi and Hayanmi varieties) baked by far-infrared radiation. Sweet potato chips were prepared by different slicing thickness (1~3 mm), concentration of sucrose solution for soaking (15~30%), blanching time (15~60 sec), baking temperature ($110{\sim}140^{\circ}C$) and baking time (23~31 min) through sensory evaluation and failure stress measurement. Optimal processing condition of sweet potato chips using Shinjami was determined to 1 mm, 20%, 45 sec, $120^{\circ}C$ and 31 min, and those using Juhwangmi was determined as 1 mm, 25%, 45 sec, $130^{\circ}C$ and 29 min. Sweet potato chips using Hayanmi was determined as 1 mm, 20%, 45 sec, $120^{\circ}C$ and 31 min, respectively. Free sugar content of sweet potato chips was higher in chips than in raw materials. In the sensory evaluation, appearance, sweet taste, hardness, and overall acceptance were higher in Juhwangmi than in the Shinjami and Hayanmi varieties. Overall acceptance, sugar content, b-value and failure stress were highly correlated among factors affecting the sensory characteristics (p<0.01). From the results of this study, Juhwangmi variety was selected for production of sweet potato chips.

• Journal of agriculture & life science
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• v.44 no.2
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• pp.57-66
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• 2010

The antioxidant and neuronal cell protective effects of water extract from purple sweet potato were investigated. The total phenolics and monomeric anthocyanin contents of purple sweet potato extract were 44.25 mg/g and 2,394 mg/L, respectively. The antioxidant activities of purple sweet potato extract were evaluated using various antioxidant tests, including 1,1-diphenyl- 2-picrylhydrazyl (DPPH), 2,2'-azino- bis-(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging activities, ferric reducing/antioxidant power (FRAP) and reducing power. In these assays, the extract of purple sweet potato presented significant radical scavenging activities, FRAP, and reducing power in a dose-dependent manner. MTT {3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyl- tetrazoliumbromide} reduction assay showed significantly increase in cell viability when PC12 cells were pretreated with purple sweet potato extract. Because oxidative stress is also known to increase neuronal cell membrane breakdown, we further investigated by lactate dehydrogenase (LDH) and neutral red uptake assay. Purple sweet potato extract inhibited oxidative stress-induced membrane damage in neuronal cells. Therefore, these data results demonstrated that water extract of purple sweet potato have antioxidant activity and neuronal cell protective effect thus it has great potential as a natural source for human health.

• Preventive Nutrition and Food Science
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• v.7 no.4
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• pp.405-410
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• 2002

Rice wine was prepared with medicinal plants or plant extracts to obtain a value added nutritious alcoholic tonics. Powders of ten medicinal plants (PTM) or aqueous extracts prepared from them (ATM) were added during the initial stage of fermentation. Aroma compounds of rice wine (control) and wines containing PTM or ATM were isolated by liquid-liquid continuous solvent extraction (LLCSE) and analyzed by gas chromatography-olfactometry and aroma extract dilution analysis (AEDA). Desirable aroma compounds: acetaldehyde (sweet, ethereal), benzaldehyde (sweet, fragrant), ethyl acetate (sweet) and ethyl octanoate (sweet, ethanolic) had the highest log$_3$-flavor dilution (FD) factors in ATM. Results of sensory evaluation demonstrated that intensities of undesirable aroma attributes, such as koji and yeasty notes in control, and raw medicinal herb notes in PTM, were lowest in wine with ATM. Wines made with ATM had the most attractive aroma attributes among the three different traditional Korean medicinal wines.

• Applied Biological Chemistry
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• v.44 no.2
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• pp.88-91
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• 2001

Mixtures of rice and sweet persimmons to make sweet syrup, jochung, were saccharified by barley malt. Soluble solid contents, reducing sugar and free sugar contents, and sensory quality were determined in jochungs, which were prepared from various ratios (10 : 0, 7 : 3, 5 : 5, 3 : 7) of rice to sweet persimmons. Amylase activity had the highest value, 10466 Unit, after 3 hrs during saccharification process at $55^{\circ}C$. In HPLC determination of free sugars, maltose in saccharifying liquids found the highest amount followed by fructose and glucose. With increasing amounts of sweet persimmons, fructose and glucose contents increased while maltose content decreased. The soluble solid contents reduced as the sweet persimmons proportions increased. The control group without sweet persimmons showed highest value, $58^{\circ}Brix$, in soluble solid content. There appeared to be a slight decrease in reducing sugar and free sugar contents as proportion of sweet persimmons increased. Jochung prepared at high amounts of sweet persimmon had better scores in overall acceptance.

• Journal of the Korean Society of Food Culture
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• v.28 no.4
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• pp.386-391
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• 2013

This study investigated the effects of freeze-dried sweet pumpkin powder on the baking of bread. Freeze-dried sweet pumpkin powder (0, 3, 6, 9, or 12%) was supplemented during the baking process and the bread volume, weight, specific volume, baking loss rate, texture, and sensory characteristics were measured. The results were following. Freeze-dried sweet pumpkin contained 4.88% water, 4.40% protein, and 4.02% ash. The L-values (brightness) of the bread were significantly lower as increasing amounts of sweet pumpkin powder were added (p<0.001). However, higher values for the a-value (redness) and b-value (yellowness) were observed (p<0.01 for both values). The volume and baking loss rate decreased when the sweet pumpkin powder was added. In contrast, the weight significantly increased as sweet pumpkin powder was added (p<0.01) and the intensity of dark brown color increased. The outer side of the bread was balanced overall, but the outer skin of the bread appeared darker as the amount of sweet pumpkin powder increased. The overall acceptability, hardness (p<0.001), elasticity (p<0.01), cohesiveness (p<0.01), gumminess (p<0.01), and brittleness (p<0.001) increased as sweet pumpkin powder increased as well. However, when sweet pumpkin powder was added at 12%, the overall acceptability value was fairly low. Sensory parameters, such as taste (p<0.001), color (p<0.001), and flavor (p<0.05) were observed when sweet pumpkin powder was used at 3% and these results were lower than the control. Overall acceptability (p<0.001) was best when sweet pumpkin powder was used at 9% and the texture was best when sweet pumpkin powder was used at 6%.

• Journal of Life Science
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• v.16 no.3 s.76
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• pp.396-399
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• 2006

Crude extract prepared from sweet potato possessed inhibitory activity toward mushroom tyrosinase. The inhibitory activity was dependent upon the addition amount of sweet potato extract. After heating the sweet potato extract at $95^{\circ}C$ for 20 min, its inhibitory activity retained 37.3%. Its optimum activity was shown at pH ranges of 5.0-7.0. The tyrosinase inhibitory activity was disappeared by dialysis, which suggests the inhibitory activity of sweet potato extract is caused by some compounds of low molecular weight.

• Food Science and Biotechnology
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• v.15 no.6
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• pp.986-989
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• 2006

Sweet potato starch noodles prepared without freezing exhibited higher cooking loss and water uptake during cooking and usually resulted in noodles with a softer and stickier texture compared to commercial sweet potato starch noodles manufactured using a freezing process. By utilizing the starches of different plant sources (potato, cowpea, and sago in an equivalent mixture with sweet potato starch), however, the cooking properties and texture of the starch noodles could be improved. Among the starches tested, cowpea starch was most effective in providing cooking and textural properties similar to those of commercial noodles. As an alternative approach, the addition of a minor amount (0.1 % based on total solid weight) of various gums (xanthan, gellan, locust bean gum, curdlan, and carboxymethyl cellulose) was also examined. The addition of curdlan to noodles was effective in increasing the gumminess and hardness, and reducing the stickiness of noodles. Utilizing different starches and gums can improve the overall texture and quality of sweet potato starch noodles produced without freezing.

• Korean Journal of Food Science and Technology
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• v.20 no.3
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• pp.412-418
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• 1988

Granular shapes and sizes, physicochemical priperties and gelatinization patterns of sweet potato starches from Wonki(the dry type) and Chunmi(the moist type) were investigated. Starch granules of sweet potatoes were round. Granule sizes of Wonki starch were mainly $11{\mu}m$ and those of Chunmi starch were $12{\mu}m\;and\;17{\mu}m$. Wonki starch had lower water binding capacity and swelling power than Chunmi starch. But Wonki starch had higher amylose content, gelatinization temperature, miture content for gelatinization and temperature for gelatinization than Chunmi starch.

• Journal of the Korean Society of Food Culture
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• v.27 no.2
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• pp.202-210
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• 2012

The purpose of this study was to bake sweet rice muffins with oak mushroom ($Lentinus$ $edodes$) powder. The process included substituting sweet rice flour for cake flour and adding oak mushroom powder. This study determined the optimal mixing conditions of oak mushroom muffins by adjusting the amounts of oak mushroom powder, whole eggs, and soybean oil. The mixing conditions for the oak mushroom muffins included 3 categories: oak mushroom powder (X1), whole eggs (X2), and soybean oil (X3) by Central Composite Design (CCD) which was optimized by Response Surface Methodology (RSM). Oak mushroom muffin formulation was optimized using rheology. Yellowness (p<0.001) and redness (p<0.05) displayed a linear model pattern, whereas lightness (p<0.05) was represented by a quadratic model. Among the sensory properties, variables that appeared to show significant values such as appearance (p<0.5), texture (p<0.5), and overall quality (p<0.5) were used to identify optimums. The result of mechanical properties showed significant values in gumminess (p<0.5) and chewiness (p<0.5). The numerical and graphical methods used in this study determined that the optimum formulation for oak mushroom powder sweet rice muffins was 8.75 g of oak mushroom powder, 235.95 g of whole eggs, and 19.93 g of soybean oil.