• KSBB Journal
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• v.26 no.1
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• pp.49-56
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• 2011

Volatile components of crude fucoidan and its raw material, Undaria pinnatifida sporophylls were identified by GC/MSD analysis, and the effects of a combined method of solvent extraction and drying (hot-air drying or spray drying) on deordorization of fucoidans were examined. The major components of seaweed smell (odor) in crude fucoidan and Undaria pinnatifida sporophylls were identified as alkanes (octadecane, heptadecane, tetradecane) and acids (hexadecanoic acid, oleic acid). Solvent extraction and drying were combined for the deordorization of fucoidans: hot-air drying/deordorization process (HDDP) and spray drying/deordorization process (SDDP). The deordorization effects of solvent extraction using solvents including water, ethanol, and acetone were investigated. Among the tested solvents, ethanol was selected as a deordorization solvent, because the seaweed smell and taste were mostly lowered by ethanol extraction followed by drying. In addition, HDDP and SDDP were compared, showing that SDDP gave higher sensory characteristics than HDDP. When the crude fucoidan was treated by ethanol extraction for 30 min followed by SDDP, approximately 60% of off-flavor components of crude fucoidan was removed based on GC/MSD peak area, and the total sugar and sulfate contents and APTT-anticoagulant activity significantly increased compared to crude fucoidan. In conclusion, SDDP after ethanol treatment was proposed and established as a deordorization process for fucoidan preparation.

• Preventive Nutrition and Food Science
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• v.14 no.4
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• pp.329-334
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• 2009

The effects of drying conditions on the antioxidant activities, luteolin, and volatile compounds of Chrysanthemi Flos flowers were evaluated. The flowers were dried with hot-air or far-infrared radiation at 40${^{\circ}C}$, 50${^{\circ}C}$ and 60${^{\circ}C}$, respectively, to reach 22$\pm$1% of moisture content. Each 10 g of the dried flowers were extracted with 100 mL of 95% ethanol. Increasing temperature in hot-air dried (HAD) conditions increased the antioxidant activities of the flower extracts. However, increasing temperature in far-infrared dried (FID) conditions decreased the antioxidant activities of the extracts. Luteolin, one of main flavonoids of Chrysanthemi Flos flowers, was present in the highest content at 60${^{\circ}C}$ FID flowers with a value of 139 $\mu$g/mL. Thirteen volatile compounds including camphor and β-caryophyllene were identified in chromatograms. Higher amount of the volatiles were found at 50${^{\circ}C}$ HAD and 40${^{\circ}C}$ FID. The results indicated that the antioxidant activities and volatile compounds of Chrysanthemi Flos flowers were significantly affected by drying conditions.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.3
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• pp.572-578
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• 1999

This study was conducted to investigate processing condition and characteristics of chestnut paste. The kinds of chestnut powder processed with blanching and drying of raw material were four named RH(not blanched, hot air dried), RF(not blanched, freeze dried), BH(blanched, hot air dried) and BF(blanched, freeze dried). Blanching affected the reduction of drying time in chestnut. Water absorption index of the blanched samples were higher than the nonblanched. Blanching affected the viscosity of pastes when water was added to process paste also, but drying methods did not affected to it. The proper ratio of water to the powder to process paste was 1.3 to 1.5 times in RH and RF, whereas 2.7 times in BH and BF by sensory evaluation. Soluble tannin content of paste was higher in RF and RH paste than BF and BH. Vitamin C content was the highest(88.49mg/100g) in RF paste and reducing sugar content was the highest in RF paste. Hunter's L and a values were the highest in BF and RH pastes, respectively, among the all paste samples. Volatile compounds detected from chestnutpastes were hydrocarbons, alcohols, phenols, ketones. The major volatile compound in all the pastes was 2,6 bis(1,1 dimethylethyl) 4 methyl phenol.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2022.09a
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• pp.115-115
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• 2022

The Food and Agriculture Organization (FAO) has been estimating the potential of insects as human food and animal feed for convincing food security since 2010. On account of this reason, Tenebrio molitor larvae have been gaining considerable attention as an alternative protein source for various foods. However, consumers do not prefer them because of their disgusting appearance. Therefore, it is necessary to develop a method that improve their appearance as to lead to T. molitor larvae consumption. In this study, T. molitor larvae which is prepared for optimally sampling conditions (shade drying, 30 min boiling after hot air drying, 30 min steaming after hot air drying), were cultured with Cordyceps militaris mycelia, and measured growth and density of mycelial. Also analyzed the cordycepin and adenosine content compared with commercial C. militaris. As a result, T. molitor larvae cultivated with C. militaris mycelia showed the highest cordycepin content (13.75 mg/g) was observed in optimal sampling conditions (shade drying). Therefore, we report that the methods which T. molitor larvae cultivated with C. militaris mycelia not only improve their appearance but also increase cordycepin content, which can be contributed to lead T. molitor larvae consumption.

• Food Science and Biotechnology
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• v.16 no.2
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• pp.187-192
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• 2007

The objectives of this study were to examine changes in the color and antioxidant compounds of paprika powder under various conditions, as well as to establish the suitable conditions for drying and storage. Paprika was dried using the following methods: freeze-drying, vacuum drying, far infrared-ray drying, and hot-air drying. Measurements of the moisture content, color pigments, and antioxidant compounds (total carotenoids, capsanthin, ascorbic acid, and total polyphenols) were completed during 120 days of storage at 4 and $30^{\circ}C$. We found that drying methods, storage temperatures, and packaging materials affected the American Spice Trade Association (ASTA) and Hunter color values, as well as the antioxidant content of paprika powder. There was a high correlation (r=0.87, p<0.01) between the ASTA color and the $a^*/b^*$ value. The loss of red color was closely related to the reduction of moisture content (r=0.81, p<0.01) during storage. Drying paprika with a low temperature in the absence of air resulted in better retention of the carotenoids and ascorbic acid. Also, as the retention of the carotenoids and ascorbic acid increased, the stability of the red pigment increased. Freeze-drying was found to be the most suitable drying method for the stability of the antioxidant compounds and red pigment.

• Food Science and Preservation
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• v.4 no.2
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• pp.147-153
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• 1997

Oriental melon has been increased in production amount, but its processed food was not made in spite of the fact that shelf-life of the fresh fruit is short. This study was carried out to develop a dried product with no use sulfur treatment. Fresh melons were peeled, cut into 6 pieces, and soaked to the following pretreatments soaking in sugar syrup(SS), sodium chloride(SC), ascorbic acid(AA) and sodium polyphosphate(SP). After preatreatments the melon pieces were dried by hot air drying at 5$0^{\circ}C$ for 9 and 12 hours, and the dried melons were air blown at $25^{\circ}C$ for 1 day. The dried samples were evaluated for moisture content, texture, rotor, and sensory quality. The moisture content of dried melons soaked in SS and SC were lower than those that were soaked in AA and SP after hot air drying. The melons dried for 12 hours were high in hardness, gumminess, chewness and adhesiveness and excellent in sensory evaluation compared to 9 hours. The "L" value of SS was higher and the "a" value was lower in Hunter color. And SS treatment inhibited browning of the dried melon and improved sensory characteristics in color, flavor, texture and taste. Sucrose concentration had no significant effect on color, hardness and sensory score in banal product. The combination of SS with SP represented a highly effective antibrowning treatment for the dried melon and the product was kept in good color for 3 months at room temperature.at room temperature.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11b
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• pp.388-395
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• 2000

This study was performed to examine the effects of infrared (IR)/heated-air combination drying on some quality attributes of Korean white ginsengs. Ginseng roots were dried in a dryer where both the far infrared ray and heated-air are available as drying energy sources. Diametral shrinkage, external color, total saponin content, and ginsenosides and free sugar composition of the IR/heated-air combination dried ginsengs were measured and compared with those of commercial white ginseng products. The external color became lower in lightness and higher in saturation as the IR radiating plate temperature increased. IR/heated-air combination dried white ginsengs at IR plate temperature of 100$^{\circ}C$ was comparable to the commercial white ginseng products in color characteristics. Diametral shrinkage ratios ranged from 20 to 36% and appeared to be independent on the different drying methods. No definite evidence could be found whether the IR/heated-air combination drying and the conventional. hot-air drying practice resulted in white ginsengs having different ginsenoside contents and compositions. No conclusion could be made on whether the various drying treatments used in the study had effects on the free sugar contents and compositions of white ginsengs.

• Korean Journal of Food Science and Technology
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• v.51 no.6
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• pp.524-530
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• 2019

Kelp (Saccharina japonica) contains various bioactive compounds, including vitamins, minerals (especially iodine and potassium), alginic acid, fucoxanthin, and various antioxidants. Kelp is mainly used as a dried product. The purpose of this study was to investigate the stabilities of antioxidant capacities and fucoxanthin of kelp by different conventional drying conditions including hot air drying at 70℃ and natural drying methods. Fucoxanthin, total phenolic contents, and total antioxidant capacity by ABTS, DPPH, and FRAP assays were significantly decreased after 5 to 10 h of hot air drying at 70℃. The assay values were also significantly decreased by 50% after 2 days of drying due to ultraviolet exposure. The findings demonstrate that heat and ultraviolet exposure during drying of kelp could affect the degradation of bioactive compounds, especially fucoxanthin and polyphenols. Optimal conditions should be considered during kelp drying and storage.

• Food Engineering Progress
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• v.13 no.2
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• pp.105-109
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• 2009

The effects of drying methods on the physicochemical properties of Salicornia herbacea powder were investigated. Samples prepared by freeze drying showed a significantly higher L$^{*}$-value but lower a$^{*}$-value as compared with those prepared by hot-air drying and vacuum drying (p<0.05). Scanning electron micrograph revealed that freeze drying produced more orderly and denser samples than did vacuum and hot-air drying. Water solubility of the freeze-dried sample was significantly higher than those of the other methods while swelling ratio of the same sample was significantly lower than those of others (p<0.05). Freeze-dried Salicornia herbacea powder contained significantly higher amounts of total sugar and reducing sugar as compared to the other samples (p<0.05).

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.6
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• pp.893-900
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• 2014

The aim of this study was to investigate physicochemical changes in Salvia plebeia R. Br. (SPA) upon hot-air drying and blanching. After hot-air drying and blanching, total polyphenol and flavonoid contents were reduced from 96.64 mg and 48.40 mg gallic acid equivalent/g to 29.70 mg and 22.10 mg quercetin equivalent/g, respectively. DPPH radical scavenging activities at $25{\mu}g/mL$ of SPA were 94.5% for ascorbic acid, 84.3% for hot-air dried SPA, and 59.7% for blanched SPA and there was no significant difference between those of hot-air dried SPA and ascorbic acid as a positive control. Total sugar contents were 7.187% and 6.104% for hot-air dried SPA and blanched SPA, respectively. During the blanching process, sucrose and maltose contents decreased, whereas glucose and fructose contents increased. Glucose and fructose were converted into citric acid in blanched SPA, whereas sucrose and maltose were converted into tartaric acid, malic acid, and succinic acid. Fourteen kinds of amino acids were found, but methionine, lysine, glycine, histidine, and cysteine were absent. The proportion of essential amino acids was 61.76% upon hot-air drying, which was a relatively high amount. In addition, hot-air drying resulted in 1.40 mg/100 g of norvaline as well as 39.00 mg/100 g of GABA, which are non-amino acids. Therefore, Salvia plebeia R. Br. can be used not only as vegetables but also as highly useful and various health functional foods with antioxidant effects and excellent nutrition.