• Journal of Biosystems Engineering
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• v.29 no.1
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• pp.37-44
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• 2004

This study was conducted to develop a new drying method far reducing the drying cost and time and to investigate the drying characteristics of oak mushroom. A far infrared dryer of down draft air flow type used for this experiment can control the drying parameters, such as far infrared heater temperature and aeration velocity. The far infrared drying tests were performed at aeration velocities of 0.3 and 0.6m/s under the temperature of 90 and 100$^{\circ}C$ in for infrared heater, respectively. The results were compared and analyzed with those of an heated air drying method used as a control in terms of properties representing the drying characteristics. such as shrinkage rate, color, energy consumption amino acid components, drying rate and moisture ratio. The results obtained from this research can be summarized as follows. 1. The drying rate of far infrared drying was faster than that of heated air drying. With high temperature of far infrared heater and slow aeration velocity, the far infrared drying of down draft air flow type was superior to the heated air drying. 2. Most of far infrared drying conditions required less energy consumption than heated air drying. 3. The shrinkage rates of heated air drying and far infrared drying were decreased by 17.0% and 18.2∼19.8%, respectively. 4. The difference of color on oak mushroom surface before and after drying can be represented as $\Delta$E. $\Delta$E values of far infrared drying and heated air drying were 2.39∼4.55 and 6.77, respectively. 5. The amounts of free amino acids were higher in the far infrared than in the heated air drying. In addition the amounts of Gln and Glu generally were increased and those of Ala, Leu, and Val were decreased in order.

• Journal of Preventive Medicine and Public Health
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• v.19 no.2 s.20
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• pp.167-176
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• 1986

For the purpose of determinating the normal values of some parameters relevant to lead exposure, a study was carried out from April 1 to June 30, 1986 on 258 healthy Korean adults who have had no apparant lead exposure. The lead indices subjected to this study were as follows; blood lead (PbB), hemoglobin (Hb), zinc protoporphyrin in blood (ZPP), delta-aminolevulinic acid dehydratase (ALAD) activity in blood, coproporphyrin in urine (CPU), delta-aminolevulinic acid in urine (ALAU). 1) The mean value of PbB was $17.17{\pm}7.87{\mu}g/100ml$, and there was no statistically significant difference by age & sex. The distribution of PbB fitted to the log-normal distribution ($x^2=7.38$, p>0.1). 2) The mean value of Hb in male ($15.17{\pm}1.56g/100ml$) was higher than in female ($13.22{\pm}1.51g/100ml$)(p<0.01). The distribution of Hb fitted to the normal distribution ($x^2=9.40$, p>0.1). 3) The mean value of ZPP was $32.61{\pm}8.78{\mu}g/100ml$, and there was no statistically significant difference by age & sex. The distribution of ZPP fitted to the normal distribution ($x^2=13.93$, p>0.05). The correlation of ZPP & ALAD (r=-0.229), CPU (r=0.183) was statistically significant respectively. 4) The mean value of ALAD was $30.20{\pm}10.96{\mu}mol$ ALA/min/L of R.B.C., and there was no statistically significant difference by age & sex. The distribution of ALAD activity did not fit to the normal distribution. The correlation between ALAD & PbB (r=-0.219) was statistically significant 5) The mean value of CPU was $36.10{\pm}24.54{\mu}g/L$, and there was no statistically significant difference by age & sex. The distribution of CPU did not fit to the normal distribution. The correlation between CPU & PbB (r=0.185), ZPP (r=0.183) was statistically signinificant respectively. 6) The mean value of ALAU was $1.94{\pm}0.96mg/L$, and there was no statistically significant difference by age & sex. The distribution of ALAU fitted to the normal distribution ($x^2=9.76$, p>0.1).

• Korean Journal of Food Science and Technology
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• v.27 no.4
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• pp.487-494
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• 1995

To assay the quality of anchovy sauce, 10 kinds of commercial anchovy sauce(CAS) were purchased from markets and traditional anchovy sauce(TAS) were prepared. And their physicochemical-microbial characteristics were compared. The compositions of CAS were as followed; pH $5.5{\sim}5.7$, salinity $21.0{\sim}23.2%$, VBN $92.8{\sim}305.4\;mg/100g$, total nitrogen $928.0{\sim}1870.9\;mg%$, amino-nitrogen $338.6{\sim}680.3\;mg%$, and acidity $11.58{\sim}24.58\;ml$. The CAS was lower in pH, smaller in contents of VBN, total-N, amino-N and larger in contents of moisture, salinity than TAS. In Hunter values, CAS was generally lower in L, b values whereas higher in a and ${\Delta}E$ values than TAS. Viable cell counts on 0% NaCl-medium of CAS and TAS were $6.4{\times}10^1{\sim}3.0{\times}10^5\;and\;8.7{\times}10^4$, and those on 2.5% NaCl-medium were $0.8{\times}10^2{\sim}2.2{\times}10^5\;and\;1.6{\times}10^4{\sim}4.5{\times}10^5$, respectively. These viable cell counts in CAS and TAS were gradually decreased according to storage time. In composition of extractives, total free amino acid contents of CAS and TAS were $5498.5{\sim}12123.8\;mg%$, 12797.9 mg%, and these contents were gradually decreased during storage. The major amino acids were found glutamic acid, alanine and leucine in CAS, and alanine, glutamic acid, leucine and valine in TAS. Also contents of hypoxanthine, TMAO, TMA in CAS and TAS were shown $86.4{\sim}161.2\;mg%,\;51.6{\sim}99.2\;mg%,\;23.2{\sim}42.9\;mg%$ and 103.7 mg%, 128.8 mg%, 55.8 mg%, respectively. We may conclude from the results of present experiments that parts of tested CAS were somewhat putrefied and there was a great difference in the quality compared with TAS, whereas TAS maintained good conditions for preserving the quality until storage 2 years.