• The Korean Journal of Food And Nutrition
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• v.14 no.1
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• pp.28-33
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• 2001

During storage of 45°Bx cloudy and 72°Bx clear apple juice concentrates for up to 16 weeks at 4$\^{C}$ , -3$\^{C}$ and -15$\^{C}$ respectively, the changes of viable microbial counts, physicochemical properties were investigated and the correlation between the physicochemical properties were determined. During storage for up to 16 weeks, any viable microbes were not found in 45°Bx cloudy apple juice concentrate stored at -3 and -15$\^{C}$ and in 72° Bx clear stored at all three temperature. There were little change in pH and tillable acidity except 45°Bx cloudy apple juice concentrate stored at -4$\^{C}$ . As longer storage time and higher storage temperature, was shown higher redness of color(a value) and alcohol soluble color(ASC) in common. Vitamin C contents were more rapid decreased proportionally to time and temperature of storage. The high correlation coefficients were shown of 0.957∼0.967 between redness and ASC and -0.936∼ -0.864 between redness and vitamin C contents of apple juice concentrate during storage.

• Food Science and Preservation
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• v.20 no.5
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• pp.720-726
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• 2013

This study was carried out to optimize the filtration, clarification, anti-browning processing conditions of clear pear juice and to investigate changes in antioxidant activity of pear juice produced through different heating treatment. For the filtration with cheese cloth, filter paper, or centrifugation (10 min at 3,000 rpm), the pear juice was most efficiently filtered with centrifugation because it showed the highest lightness (L value) and lowest yellowness (a value). Among various clarifying agents, 1% of gelatin or bentonite clarified effectively pear juice but tannin or egg albumin did not. Among anti-browning agents (0.1%) like L-ascorbic acid, NaCl or citric acid, L-ascorbic acid prevented the browning of pear juice with the lowest browning index value (2.62), compared to that of NaCl (2.74), or citric acid (2.87). Fructose, sucrose, glucose and sorbitol were present in the pear juice, the fructose and glucose contents increased but that of sucrose decreased in the heated pear juice. The total polyphenol content of the heated pear juice significantly increase, and did the total flavonoid contents in the clear and heated pear juice. The DPPH radical scavenging activity and nitrate scavenging activity were higher in the clear and heated pear juice than in the fruit crush.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.8
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• pp.1051-1056
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• 2006

Response surface methodology was used to investigate the quality of clarified mixed apple and carrot juices using ultrafitration. Apple and carrot juices were blended at the ratio of 1:3, 1:1, and 3:1. A three-variable, three-level central composite design was employed where the independent variables were the blend ratio, temperature and average transmembrane pressure (ATP). With increasing temperature and pressure, flux linearly increased regardless of blending ratio. Blend juice with 75% apple showed the highest soluble sugar and total sugar content in apple and carrot blend juices. Soluble solid contents were more affected by blending ratio than temperature and ATP. Total sugar contents were greatly affected by temperature; increasing temperature led to higher total sugar content up to $25^{\circ}C$. Higher carrot ratio led to higher vitamin C content. In general, higher acidity was achieved by higher apple content and acidity was increased with increasing temperature. Turbidity increased for all samples as APT increased, with the blending ratio of 1:1 (apple:carrot) showing the highest turbidity. Viscosity was greatly changed in the blending ratio of 3:1 (apple:carrot) juice. The polynomial models developed by RSM were satisfactory to describe the relationships between the studied factors and the responses. Analytical optimization gave $flux=0.216\;L/m^2.h$, soluble $solids=10.39^{\circ}Brix$, total sugar=71.32 mg/mL, vitamin C=315.18 mg%, acidity=7.78 mL, turbidity=0.017, and viscosity=1.44 cp, when using a $temperature=44.97^{\circ}C$, ATP=113.57 kPa, and blend ratio=28.50%.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1420-1425
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• 1998

Rice wines, Yakju-type, were brewed with typical raw materials plus powdered acorns, and storage qualities of the fermented wines were examined. Initial optical densities of the acorn added-rice wines were shown around 0.116 at 660 nm and then decreased to $0.06{\sim}0.075$ after 10 days storage at $4^{\circ}C$. Organic acid contents in the acorn added-rice wines were lower than that of the control: the contents were lactic, succinic, citric, malic, oxalic and fumaric acid in order; and gallic acid, a kind of tannic substances was 0.39 mg%. Peroxide values of the acorn added-rice wines were not markedly changed for 9 days, remaining as low as $2{\sim}3\;meq\;kg^{-1}$ lard of lard, but that of the control was increased to $265\;meq\;kg^{-1}$ lard. As the results of clarity, acidity and antioxidation, the acorn added-rice wines appeared to be preservable, owing to tannic substances extracted from acorn powder.

• Food Engineering Progress
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• v.14 no.1
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• pp.41-48
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• 2010

An optical method was introduced to investigate the dispersion stability of Saengshik beverages (SB) containing 3.7-11.7% Saengshik powder (SP). Time course changes in backscattering light flux (BSLF) from SB were monitored by a Turbiscan. BSLF in the bottom and top layers of SB increased by forming sediment and foam, respectively, while that in the middle layer decreased by clarifying. With SP levels, sedimentation in SB was retarded, but the height of total sedimentation layer was increased. A logarithmic model was developed to fit to the changes in BSLF with time, showing determination coefficients of 0.979-0.988. The levels of SP in SB influenced the migration speed of the clarification front as well as the numbers of separated layers; 2 layers in SB containing 3.7% SP, 3 in 5.7-9.7%, and 4 in 11.7%. Formation of clear layers started after 17-29 min and continued for 22-53 min. The clarification was retarded most in SB containing 7.7% SP, indicating the most stable SP level for the SB preparation.

• Korean Journal of Microbiology
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• v.19 no.3
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• pp.121-127
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• 1981

The constituents of molasses and effect of pH precipitate formation in molasses solution, vary according to its producing districts. The formation of precipitation is not so changeable in the range of buffering zone of molasses solution(pH4.3-6.3) in philippine molasses according to the change of pH value. On lower or higher than the range of buffering zone, the precipitation is increased from pH 4.3 to 2.8 and from 6.3 to 8.1, it is decreased when pH value is lower or higher than the pH value range. For molasses clarifying, it had better adjust the pH of molasses solution to neutral or weak alkali range out of the alkai side of the buffering zone, with lime solution. And then, add the calcium super phosphate solution to pH value of alkali side in buffering zone, as much as the pH of clarified molasses solution can reach to middle value in buffering zone. For the equilibrium of pH value on clarifying molasses, it takes plenty of time more than 6 hours.

• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.448-457
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• 1999

Citrus fruits are consumed worldwide due to their unique flavor and nutrition value. It is necessary to remove the haze material as well as to minimize the loss of major compounds such as organic acids, sugars, and ascorbic acid in membrane processes for clarification of juice. The objective of our research was to select the best membrane among one surface filter (Whatman No.4) and five microfiltration filters (GF/A, GF/D, GF/F, Gelman, and SM). Tangerine fresh blended with three times of water was partially clarified with 170 mesh followed by prefiltration in a Samduck filtration system. The best membrane was selected by measuring the amounts of major compounds in the permeates as well as the flux which were statistically analyzed with SAS program. The foulants on the membrane surface were observed by SEM. The flux of GF/A and GF/F decreased with time at probability 0.10. Gelman, SM, and GF/D maintained the stable flux. Gelman showed the highest total scores including nutritive value (the amounts of citrate, malate, and ascorbic acid) and purchasing need (brix and color). Therefore, the microfiltration membrane process was a very effective method in tangerine juice clarification and Gelman type A/E was proved to be the best membrane among the five microfiltration membranes.

• Journal of Korean Society on Water Environment
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• v.32 no.6
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• pp.537-545
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• 2016

In order to cope with the new and strict government regulations for turbid water discharge from construction sites, this study tested whether synthetic fiber filters can replace conventional best management practices. The filter efficiency was about 10 to 60% with a varying filter depth of 5 to 15cm, presuming extreme storm flow conditions to be in the range of 800 to 1500m/day of filtration rates. Fiber filter acts exactly like a granular filter, i.e. the separation efficiency is directly and inversely proportional to filter depth and rate, respectively. Based on the operational data, we suggested the Log-Log design relationship, which can be used to determine the filter depth and area. Compared to the widely used gravel filter which treats the turbid water at the construction site, about 20% higher efficiency was obtained under similar operating conditions. Cleaning the filter through a simple hand-washing method at the time of break-through, achieved about 90% soil recovery.

• Journal of Korean Society on Water Environment
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• v.31 no.3
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• pp.262-271
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• 2015

Laboratory study was undertaken to pursue the filter performance of a micro-filter module employing highly porous fiber media under a high filtration rate (over 1,500 m/day), faster than that of any conventional filter process. The effects of filtration rate, head loss, raw water turbidity, and filter aid chemicals on filter performance were analyzed. In spite of the extremely high filtration rate, the filter achieved an attractive efficiency, reducing the raw water turbidity by over 80%. As with other filter systems, the filter aid used (PAC in this study) greatly affected the performance of this particular fiber filter. Long term repetitive runs were additionally carried out to confirm the reproducibility of the filter performance. Finally, a comparison was carried out with other high rate filter systems which are either being tested for use in experimental studies, or are already commercially available.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.4
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• pp.810-815
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• 1999

The pectinase treatment conditions for clarification of persimmon vinegar were optimized and monitored by response surface methodology. In clarification of persimmon vinegar by pectinase treatment with variations in temperature, time and concentration, coefficients of determinations(R2) of the models were above 0.91(p<0.05) in turbidity, browning color intensity and tannin content. The turbidity of persimmon vinegar was decreased along with an increase of pectinase treatment temperature. The minimum value of turbidity by pectinase treatment was 0.0021(absorbance at 660nm) in 49.38oC of pectinase treatment temperature, 73.08min of pectinase treatment time and 55.57ppm of pectinase concentration. The minimum value of browning color intensity by pectinase treatment was 0.27(absorbance at 660nm) in 48.39oC, 71.74min and 65.69ppm. The minimum value of total tannin contents by pectinase treatment was 43.72mg/100 ml in 40.05oC, 66.02min and 65.26ppm. The optimum conditions of pectinase treatment that satisfies the least common multiple of turbidity, browning color and tannin content were 40~50oC, 60~70min and 55~70ppm.