• 한국식품과학회지
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• 제45권2호
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• pp.161-166
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• 2013

본 연구에서는 우육 등심에 대한 마이크로파 조사효과를 검토하고 최적 조건을 확인하고자 하여 마이크로파 조사처리(연속처리방법: CW, 정지처리방법: HW)된 우육등심을 14일간 $4^{\circ}C$에 저장하면서 이화학적, 미생물학적 품질 변화를 관찰하였다. 우육의 L값은 저장 6일까지 조사선량이 증가할수록 정지처리방식과 연속처리방식 모두 감소하는 경향을 보였고 저장 10일차 이후에는 T3가 가장 높았고 T6가 가장 낮았다. 조사처리가 a, b값에 영향을 주는 것으로 나타났다. 우육의 pH는 조사 직후 0일째에 6.48-6.59였으나 3일 후에 급격히 감소되어 5.59-5.71로 나타났으며 (p>0.05) 저장 14일까지 유의적인 pH 변화가 없었다. 우육의 TBA 값은 조사선량이 높을수록 TBA 값이 증가하는 것으로 나타났으며 정지처리방식보다 연속처리방식에서 TBA 값이 낮아 지질산 패도지연에 효과적이었다. 단백질 부패도를 나타내는 VBN 값은 전 처리구간에서 대조군이 가장 높았고 조사선량이 증가할수록 낮은 단백질부패도를 보였다. 총균수는 대조군의 경우 저장 14일째 $10^8$ CFU/g인 것이 조사처리군인 T6의 경우 $10^3$ CFU/g으로 나타났다. 저온성 세균수는 대조군이 가장 높았고 저장기간이 증가하면서 증가한 반면, 조사처리군인 T6는 가장 낮은 $10^2$ CFU/g값을 저장 14일까지 유지하여 미생물 생장을 지연시켰다. 본 연구결과 우육에 마이크로파 처리가 품질을 유지하면서 미생물 생육을 지연시키는 것으로 나타났으며 우육등심의 품질변화를 최소화하면서 진공포장의 단점인 육색의 변색방지 및 미생물 억제효과를 나타내어 신선육으로 유통시킬 수 있는 최적 조건의 마이크로파 조사조건은 100 W 정지처리방식인 T2인 것으로 나타났다.

• 한국축산시설환경학회지
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• 제19권2호
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• pp.81-88
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• 2013

We planned to study how the chemical disposal designed by SOP can affect on physicochemical compositions of the livestock excrement. According to Livestock Manure Management Scheme, we experimented in two steps; the first step, NaOH treatment-Citric acid neutralization, and then the second procedure, Thermophilic Aerobic Oxidation (TAO) system. Physicochemical compositions of the 3-days-old samples after NaOH treatment were pH 10.31, EC 24.54 mS/cm, SCOD 3,022 mg/L, T-N 4,315 mg/L, $NH{_4}^+-N$ 1,960 mg/L, and not detected E. coli.. And those of one-day-old samples after citric acid neutralization were pH 7.36, EC 32.89 mS/cm, $SCOD_{Mn}$ 12,733 mg/L, T-N 4,787 mg/L, $NH{_4}^+-N$ 2,450 mg/L, and E. coli. not detected. In contrast, the physicochemical compositions of the treatment plots after the second treatment with TAO system (72hr) were pH 9.42 EC 24.21 mS/cm, $SCOD_{Mn}$ 3,660 mg/L, T-N 3,616 mg/L, $NH{_4}^+-N$ 1,190 mg/L, and no detection of E. coli.

• 한국환경과학회지
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• 제7권3호
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• pp.269-274
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• 1998

In order to develop of support medla for bloom reactor, physicochemical properties and attachability of surface of activated carbon, clay mineral, non-clay mineral, and waste mold sand were enamined. Measured physicochemical properties of materials were surface roughness, mean particle size, surface area, hydrophobicity, and surface charge. At a tested materials, activated carbon was the best attachable material and microorganisms were attached $20.1{\times}10^7CFU/cm^2$ at surface, compared with diatomaceous earth which were attached of $9.2{\times}10^7CFU/cm^2$ in our research, surface area and hydrophobicity show- ed more Influence than any other factor on attachment of microorganisms.

• 한국축산식품학회지
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• 제35권1호
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• pp.35-40
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• 2015

Super- and sub-critical water treatments have been of interest as novel methods for protein hydrolysis. In the present study, we studied the effect of sub-critical water (Sub-$H_2O$, $300^{\circ}C$, 80 bar) treatment as well as super-critical water (Super-$H_2O$, $400^{\circ}C$, 280 bar) treatment on the physicochemical properties of porcine skin (PS), which has abundant collagen. Porcine skin was subjected to pre-thermal treatment by immersion in water at $70^{\circ}C$, and then treated with sub- or super-critical water. Physicochemical properties of the hydrolysates, such as molecular weight distribution, free amino acid content, amino acid profile, pH, color, and water content were determined. For the molecular weight distribution analysis, 1 kDa hydrolyzed porcine skin (H-PS) was produced by Super-$H_2O$ or Sub-$H_2O$ treatment. The free amino acid content was 57.18 mM and 30.13 mM after Sub-$H_2O$ and Super-$H_2O$ treatment, respectively. Determination of amino acid profile revealed that the content of Glu (22.5%) and Pro (30%) was higher after Super-$H_2O$ treatment than after Sub-$H_2O$ treatment, whereas the content of Gly (28%) and Ala (13.1%) was higher after Sub-$H_2O$ treatment. Super-$H_2O$ or Sub-$H_2O$ treatment affected the pH of PS, which changed from 7.29 (Raw) to 9.22 (after Sub-$H_2O$ treatment) and 9.49 (after Super-$H_2O$ treatment). Taken together, these results showed that Sub-$H_2O$ treatment was slightly more effective for hydrolysis than Super-$H_2O$ was. However, both Sub-$H_2O$ and Super-$H_2O$ treatments were effective processing methods for hydrolysis of PS collagen in a short time and can be regarded as a green chemistry technology.

• Applied Biological Chemistry
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• 제27권4호
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• pp.252-258
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• 1984

칡 전분의 수분을 18, 21 및 24%로 조절하고, $100^{\circ}C$에서 16시간 가열 처리한 다음, 물리화학적 성질을 규명하였다. X-ray회절 양상은 수분을 24%에서 열처리한 경우 C형에서 A형으로 전환되었고, 수분 처리 수준이 높아질수록 팽화력 및 용해도는 감소하였다. 수분(24%)-열처리한 시료는 동일팽화력에서 대조구보다 높은 용해도를 보였으며, 물 결합 능력은 수분처리 수준이 높을수록 현저히 증가하였다. 칡 전분은 가열 및 냉각에 대하여 안정된 paste 점도를 보였으며, 수분-열처리에 의하여 호화온도는 증가하였고 점도는 감소하였다.

• 공업화학
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• 제24권1호
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• pp.38-43
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• 2013

ETA (ethanolamine)는 원자력 발전소 2차계통의 pH 조절제인 암모니아 대체 물질로 2001년부터 이용되고 있다. 환경적 측면에서 난분해성 유기물이며 현재 운영 중인 원자력 발전소 폐수처리설비로 처리가 불가능하다. 본 연구는 현장 시료를 사용하여 N와 COD 제거하기 위한 최적 공정과 사용 약품에 대하여 조사하였다. 폐수 중에 다량 함유되어 있는 ammonium ion은 diffused aeration system을 이용하여 95% 이상을 제거하고 혼합과산화물(sodium persulfate/sodium percarbonate)을 사용하여 산화시키고 응집제를 사용하여 물리 화학적으로 처리 후 90% 이상의 제거효과를 얻을 수 있었다.

• 한국식품과학회지
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• 제51권5호
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• pp.452-458
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• 2019

The objective of this study was to investigate the physicochemical characteristics and antioxidant potential of garlic processed using different heat treatments conditions, which is an effective method for removing the unpleasant odor and taste of raw garlic. The pH and soluble solid content of raw garlic (pH 6.07, $7.7^{\circ}Bx$) were almost equal or slightly higher than that of processed garlic samples (pH 5.06-6.09, $7.1-7.4^{\circ}Bx$). The color of processed garlic was also significantly affected. The amounts of amino acids such as ${\gamma}$-amino-n-butyric acid and few essential amino acids also increased after the thermal treatment of garlic. The antioxidant potentials of red and black garlic were higher than that of raw garlic. The polyphenol content of processed garlic ($38.51-81.51{\mu}g$ gallic acid equivalent/g sample) was significantly higher than that of raw garlic ($30.66{\mu}g$ gallic acid equivalent/g sample). These results indicated that heat treatment for different durations under a controlled environment enhanced the nutritional and functional properties of garlic.

• 동아시아식생활학회지
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• 제20권1호
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• pp.69-76
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• 2010

This study was performed to examine the effects of salt addition level on changes in the physicochemical properties and color values of salted shrimp during fermentation. Fresh shrimp were salted with different concentrations (8, 18, 28%) of Chunil salt and fermented at $20^{\circ}C$ for 160 days. In the 8% salted shrimp treatment, volatile basic nitrogen (VBN), amino nitrogen (AN), and trimethylamine (TMA) contents rapidly increased during the fermentation period, while in the 18 and 28% salt groups these increases were reduced throughout the 160 days of fermentation. Thiobarbituric acid (TBA) values increased rapidly for 120 days of fermentation and then decreased. The thiobarbituric acid values of the 18, and 28% salted and fermented shrimp groups were lower than the that of the 8% group. In addition, Hunter's color L, a, and b values decreased as the fermentation period increased.

• 한국농촌생활과학회지
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• 제10권2호
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• pp.78-84
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• 1999

This study was performed to find out the usefulness of chestnut powder recovered from the inner layer, which used to be discarded. After the Physicochemical properties of the chestnut powder were examined, breads were prepared with 10-50% of chestnut Powder and the sensory quality was compared by QDA. Bread could be made even using up to 50% of chestnut powder, and in 20-30% of chestnut powder, the sensory quality was acceptable enough compared with wheat bread. Even though the low purity of the chestnut powder affected the flavor and color, the breads contained it were generally acceptable. Therefore, the chestnut powder recovered from the inner layer can be used as the effective food resource as itself, and with the higher purification to remove inner layer, it can be applied to more diverse food.

• 한국식품저장유통학회지
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• 제4권2호
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• pp.155-162
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• 1997

This work was designed to determine the effect of steaming-Pretreatment on Physicochemical and functional properties of roasted Polygonatum odoratum roots. Steaming treatments led to some reduction in the contents of water solubles, such as total solid, reducing sugar and free-amino nitrogen of the unroasted samples. Moreover, roasting processing caused decrease in reducing sugar and free-amino acid, with increase in total soluble solid and browning color of the samples, which showed the dependence of steaming treatment as well as roasting temperature. Electron-donating ability and nitrite-scavenging ratio of the samples were also highly developed along with roasting processing at 17$0^{\circ}C$ within 35min. Considering the physicochemical and some functional parameters of water extracts of roasted samples, roasting at above 14$0^{\circ}C$ for over 55min or at 17$0^{\circ}C$ for around 35min was recommendable for the higher quality of Polygonatum odoritum tea, which conditions were similarly adapted for both steamed and unsteamed samples.