• Preventive Nutrition and Food Science
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• v.15 no.3
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• pp.244-247
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• 2010

This study was performed to evaluate the effect of drying methods on the polyphenol contents and antioxidant activities of Hizikia fusiformis. The seaweed was dried using four different conditions: vacuum drying (VD) at $20^{\circ}C$ and $30^{\circ}C$ and hot-air drying (HD) at $40^{\circ}C$ and $60^{\circ}C$. After drying, the total phenol content, DPPH and nitrite scavenging activities of the water extracts were determined. The total phenol contents were significantly (p<0.05) higher in the vacuum dried samples than the hot-air dried samples. DPPH radical was scavenged 82.67% and 83.45% by VD-20 and VD-30, and 70.44% and 71.23% by HD-40 and HD-60, respectively. At pH 1.2, Hizikia fusiformis scavenged 87.43%, 88.45%, 72.14% and 73.45% of nitrite by the treatment VD-20, VD-30, HD-40 and HD-60, respectively. Interestingly, the nitrite scavenging activity was much more reduced at pH 3.0 than at pH 1.2. Through these experiments, we were able to show that the drying conditions affect the total phenol contents and antioxidant capacities of Hizikia fusiformis.

• Journal of Microbiology and Biotechnology
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• v.29 no.7
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• pp.1053-1060
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• 2019

Thermal drying is a common process used in the food industry for the modification of agricultural products. However, while various studies have investigated the alteration in physiochemical properties and chemical composition after drying, research focusing on the relationship between different dehydration conditions and bioactivity is scarce. In the current study, we prepared dried ginger under nine different conditions by varying the processing time and temperature and compared their immunomodulatory effects. Interestingly, depending on the drying condition, there were significant differences in the immunestimulating activity of the dried ginger samples. Gingers processed at $50^{\circ}C$ 1h displayed the strongest activation of macrophages measured by $TNF-{\alpha}$ and IL-6 levels, whereas, freezedried or $70^{\circ}C$- and $90^{\circ}C$-dried ginger showed little effect. Similar results were recapitulated in primary bone marrow-derived macrophages, further confirming that different dehydration conditions can cause significant differences in the immune-stimulating activity of ginger. Induction of ERK, p38, and JNK signaling was found to be the major underlying molecular mechanism responsible for the immunomodulatory effect of ginger. These results highlight the potential to improve the bioactivity of functional foods by selectively controlling processing conditions.

• Journal of Biosystems Engineering
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• v.36 no.2
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• pp.109-115
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• 2011

Drying characteristics of squids under two dry conditions were investigated using far infrared and heated air. Dry temperatures of 40, 50 and $60^{\circ}C$ with air speed of 0.6, 0.8 and 1.2 m/s were used for evaluating far infrared squid drying. Heated air squid drying at 40 and $50^{\circ}C$ with air speed of 0.8 m/s was used as a control treatment. The two drying were evaluated in terms of drying rate, color, TBA value, aerobic bacteria, cutting shear, penetration strength, and energy consumption. The drying rate of far infrared drying was relatively faster than that of heated air drying. The drying time of far infrared drying was reduced as the drying temperature increased. The color difference of far infrared dried squids was from 18.81 to 22.85, and heated air dried squid had the color different from 23.94 to 24.09. Far infrared dried squid had relatively smaller TBA values that indicate a level of rancidity. The aerobic bacteria of heated air dried squid increased from $970{\times}10^3$ to $40,000{\times}10^3$ CFU/g before and after drying, respectively. Far infrared dried squid had relatively smaller increase (from $970{\times}10^3$ to $40,000{\times}10^3$ CFU/g). The cutting shear and penetration strength for far infrared dried squids was relatively lower. In addition, far infrared squid drying consumed relatively less energy compared to heated air drying.

• Korean Journal of Agricultural Science
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• v.47 no.3
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• pp.519-532
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• 2020

Because lotus root has a short shelf life, the quality easily deteriorates. Thus, the harvested lotus roots are processed into a variety of products. Drying is one of the simplest food preservation methods, which can increase food stability. However, the convective drying method takes a long time and requires high energy consumption. Combination drying methods have emerged to overcome the limitations of the convective drying method. This study investigated the drying characteristics of lotus root and determined the optimal drying model of lotus root depending on the microwave and hot-air combination drying conditions. The lotus root slices (5 mm in thickness and 40 mm in diameter) were dried by different drying conditions that were combined with three microwave power levels (50, 100, and 150 W) and two hot air temperatures (50 and 60℃) at a velocity of 5 m·s^-1. Eight drying models were tested to evaluate the fit to the experimental drying data, and the effective moisture diffusion (D_eff) values of the lotus root slices dried by combination drying were estimated. The combination drying time of the lotus root was significantly reduced with the high air temperature and microwave power. The effective moisture diffusion (D_eff) of lotus root was more affected by the air temperature than microwave power intensity. Logarithmic model was most suitable to describe the drying curve of lotus root in the microwave-hot air combination drying method.

• Journal of the Korean Applied Science and Technology
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• v.33 no.1
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• pp.58-66
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• 2016

This study was performed to investigate drying characteristics and quality properties of dried persimmon with vacuum drying process. Drying characteristic curve of the dried persimmon showed that the constant rate drying period and falling rate drying period exist definitely. $_{\circ}Brix$, sugar content and hardness value of the dried persimmon increased as the vacuum pressure and heating temperature increased, but L value of the dried persimmon lower. The results indicated that the optimal conditions were at vacuum pressure of 40~50kPa abs., heating temperature of $30^{\circ}C$ and drying time of 3~4days.

• Korean Journal of Medicinal Crop Science
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• v.25 no.2
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• pp.89-94
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• 2017

Background: The purpose of improving the quality of oriental medicinal herbs is to contribute to the improvement of the income of farm. The present study investigated the effect of reasonable drying methods, different storage conditions and packageing materials on quality and stability of Scutellaria baicalensis Georgi and for developing GAP (good agricultural practice) guide book. Methods and Results: Three methods of drying Scutellaria baicalensis roots produced over two years were used to estimate loss rate owing to drying, storage, and packaging. The methods of drying were categorized into natural drying (36 - 60 h by sunshine), drying with heat dryer (2 - 10 h), or drying with gas bulk dryer (2 - 10 h). After cleaning, and initial drying for a few days under controlled temperature conditions, the second phase of drying was carried out at 35, 45 and $55^{\circ}C$. Changes in hunter color values and quality under the two studied storage treatments (at $20^{\circ}C$ indoors and at $4^{\circ}C$ in a refigerator) were evaluated. Storage period for 60, 120, and 180 days in three packaging materials, PE (polyethylene package), PP (polypropylene gunnysack), and WP (watertight packing paper) were studied. Conclusions: Initial cleaning, reasonable gas drying and hot air drying, and drying in an oven at 35 and $45^{\circ}C$ after cutting the roots resulted in the lowest loss rates in S. Baicalensis root. Hunter color valuse indicated that stroage of dry roots at room temperature was better than PP packaging, and that cold stroage was better than PE packaging for long-term stability.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.5
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• pp.470-477
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• 2011

This study reviewed the effect of the drying conditions on the production of biogenic amines and lipid oxidation in semi-dried Pacific saury Cololabis saira or Guamegi. The moisture content of the Guamegi ranged from $32.71{\pm}2.37$ to $45.9{\pm}2.60$ g/100 g. The respective ranges of the acid value (AV) and peroxide value (POV) were $1.39{\pm}0.40$ to $15.79{\pm}0.47$ mg KOH/g and $76.14{\pm}2.19$ to $282.84{\pm}2.34$ meq/kg on drying for 3 days. The AV and POV increased for up to 3 days of drying and the values differed according to the amount of sunlight and temperature. However, lipid oxidation was reduced in Guamegi manufactured using a cold-air drying method. The fatty acid composition and the biogenic amine content in Guamegi during drying did not differ significantly with the drying method or drying date. The main saturated, monoene and polyene fatty acids were palmitic acid, eicosenoic & erucic acids, and eicosapentaenoic & docosahexaenoic acids, respectively. At 16.67 to 71.89 mg/kg, the histamine content was higher than that of other biogenic amines and it increased significantly during drying. In conclusion, this study showed that the packaging and drying conditions of Guamegi products need to be improved to inhibit lipid oxidation and biogenic amine formation.

• Journal of the Korean Wood Science and Technology
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• v.25 no.1
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• pp.28-36
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• 1997

Several thick board and dimension lumbers of Japanese larch(Larix leptolepis), Dahurian larch(Larix gmelini) and radiata pine(Pinus radiata) air-dried in four different seasons to compare air-drying process. Patterns of air-drying curves were influenced by climatological conditions and limber thickness. The initial drying rates of summer were the highest, followed those of fall, spring and winter. The drying times to equilibrium moisture contents for four seasons were nearly the same except for winter. However, the drying time for winter required twice more time than the other seasons. The drying time of dimension lumbers required 1.3 times more than boards. The final moisture contents were lowest during spring, highest during winter and similar between summer and fall.

• Food Science of Animal Resources
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• v.35 no.5
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• pp.597-603
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• 2015

The purpose of this study was to investigate the influence of processing conditions (temperature and time) and binding agent types (glutinous rice flour, potato starch, bean flour, and acorn flour) on the physicochemical and sensory characteristics of ground dried-pork meat product. For this purpose, ground dried-pork meat product was produced by adding several binding agents at different drying temperatures and times. The drying time affected moisture content and water activity in all drying temperature. However, under the similar drying conditions, the extent of drying varied depending on the type of binding agents. The results of sensory evaluation for texture degree and overall acceptability indicated the following: overall, higher drying temperatures and longer drying time heightened the degree of texture, and the overall acceptability varied depending on binding agent type. Physicochemical and sensory characteristics were analyzed to determine any possible correlation. The results revealed a high correlation between moisture content, water activity, shear forces, and sensory evaluation (p<0.01). However, there was no correlation with respect to overall acceptability.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.2
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• pp.12-17
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• 2003

The effects of wet pressing and drying conditions on the disintegration and physical properties of paper were investigated in order to get the basic information on the resistance of paper for aqueous solution during converting processes. Wet pressing of unbeaten bleached softwood kraft pulp increased WRV at the range of grammage investigated. The increase of WRV with grammage at low wet pressing pressure(50 psi) was obvious, while it was not significant at higher wet pressing pressure(110 psi). The changes of WRV by drying were affected by the grammage and wet pressing pressure. The poorer disintegration of sheet, the higher wet pressing pressure and drying temperature. Although the strength properties were increased with the grammage, wet pressing pressure and drying temperature, results showed different trend from those of beaten pulp.