• Title, Summary, Keyword: total acidity

Search Result 1,514, Processing Time 0.043 seconds

Analysis of Interspecific Association and Ordination on the Forest Vegetation of Mt. Odae (오대산 삼림식생의 종간친화력 및 서열분석)

  • 이호준;변두원;김창호
    • The Korean Journal of Ecology
    • /
    • v.21 no.3
    • /
    • pp.291-300
    • /
    • 1998
  • The forest vegetation of Mt. Odae based on the interspecific relationship was classified into 4 groups : Quercus mongolica, Pinus densiflora, Quercus variabilis and Patrinia saniculaefolia. Thirty-one species of Quercus mongolica group including Quercus mongolica and Acer mone, 12 species of Pinus densiflora group comprising Pinus densiflora and Spodiopogon sibiricus, 6 species of Quercus variabilis group and 4 species of Patrinia saniculaefolia were positively correlated. in the results of species ordination by principal component analysis, 7 clusters by the humidity and acidity of soil, 4 clusters by the humidity and light intensity and 7 clusters by the acidity and light intensity were formed. The plot ordination showed that the distribution of species based on the humidity, soil acidity and total organic matters was in the order of Pinus densiflora, Quercus variabilis and Quercus mongolica groups, and based on the light intensity was in the order of Quercus variabilis, Pinus densiflora and Quercus mongolica groups.

  • PDF

Improvement of Shelf-life of Yakju by Membrane Filtration (Membrane Filtration에 의한 약주의 저장성 증진)

  • Kang, Mi-Young;Park, Young-Seo;Mok, Chul-Kyoon;Chang, Hak-Gil
    • Korean Journal of Food Science and Technology
    • /
    • v.30 no.5
    • /
    • pp.1134-1139
    • /
    • 1998
  • Quality changes of filter-sterilized Yakju were examined by filtration of Yakju through membranes followed by storing at $25^{\circ}C$ for 50 days. To evaluate quality changes of filter-sterilized Yakju, pH, titratable acidity, turbidity, and viable cell numbers of total bacteria, lactic acid bacteria, and yeast were measured. Titratable acidity, turbidity and viable cell numbers of non-sterilized Yakju increased, but pH profile decreased during the storage. In filter-sterilized Yakju, titratable acidity and turbidity did not change, while viable cells of total bacteria, lactic acid bacteria, and yeast were not detected during the storage. Addition of chitosan at the concentration of 0.1% (w/v) decreased the viable cell numbers significantly showing similar pH and titratable acidity profiles with non-sterilized Yakju.

  • PDF

Effect of Paecilomyces japonica on the Microbiological Quality and Shelf-life of Jeungpyun (눈꽃동충하초(Paecilomyces japonica)를 첨가한 증편의 미생물학적 품질특성 및 저장성)

  • Park Chan-Sung;Choi Mi-Ae;Park Geum-Soon
    • Korean journal of food and cookery science
    • /
    • v.20 no.6
    • /
    • pp.561-567
    • /
    • 2004
  • The purpose of this study was to investigate the effect of Paecilomyces japonica mycelia(PJM) on pH, titrable acidity and microbiological qualify of Jeungpyun(fermented rice cake). Jeungpyun prepared with $0\~\%$ of PJM stored at $5^{\circ}C\;and\;20^{\circ}C$ for 4 weeks and 7 days respectively. Before fermentation of Jeungpyun dough, viable cells of total bacterial counts(TBC), yeasts and lactic acid bacteria(LAB) were $6.0\~9.8\times10^6,\;5.3\~9.0\times10^6,\;5.4\~8.5\times10^6\;CFU/g$, respectively. During the fermentation of dough, viable cells of TBC, yeasts and LAB increased $0.3\~0.4$ log cycle and pH was decreased whereas acidity increased as the progress of fermentation. Total viable cells in Jeungpyun before storage were $5.0\times10^1\;CFU/g$. During storage of Jeungpyun, TBC, yeasts and LAB of control group increased 2.6, 2.4, 2.1 log cycle at $5^{\circ}C$ and 4.8, 4.6, 4.5 log cycle at $50^{\circ}C$, respectively, when reached at maximum level. Major microflora of Jeungpyun was composed of yeasts and LAB during fermentation of dough and storage at $5^{\circ}C\;and\;20^{\circ}C$. Addition of PJM, inhibited the growth of microorganisms, the changes of PH and titrable acidity of Jeungpyun during storage at both of $5^{\circ}C\;and\;20^{\circ}C$. From these results, the addition of PJM extended the shelf-life of Jeungpyun during storage at $5^{\circ}C\;and\;20^{\circ}C$.

An Analysis of Long-term Trends in Precipitation Acidity of Seoul, Korea (서울지역 강수 산성도의 장기적인 경향분석)

  • 강공언;임재현;김희강
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.13 no.1
    • /
    • pp.9-18
    • /
    • 1997
  • Precipitation samples were collected by the wet- only event sampling method from Seoul during September 1991 to April 1995. These samples were analyzed for the concentrations of the major ionic components (N $O_3$$^{[-10]}$ , N $O_2$$^{[-10]}$ , S $O_4$$^{2-}$, C $l^{[-10]}$ , $F^{[-10]}$ , N $a^{+}$, $K^{+}$, $Ca^{2+}$, $Mg^{2+}$, and N $H_4$$^{+}$), pH, and electric conductivity. During the study period, a total of 182 samples were collected, but only 163 samples were used for the data analysis via quality assurance of precipitation chemistry data. The volume-weighted pH was found to be 4.7. The major acidifying species from our precipitation studies were identified to be non-seasalt sulfate (84$\pm$9 $\mu$eq/L) and nitrate (24$\pm$2 $\mu$eq/L) except for chloride. Because the Cl/Na ratio in the precipitation was close to the ratio in seawater. If all of the non-seasalt sulfate and nitrate were in the form of sulfuric and nitric acids, the mean pH in the precipitation could have been as low as 3.7 lower than the computed value. Consequently, the difference between two pH values indicate that the acidity of precipitation was neutralized by alkaline species. The equivalent concentration ratio of sulfate to nitrate was 3.5, indicating that sulfuric and nitric acids can comprise 78% and 22% of the precipitation acidity, respectively. Analysis of temporal trend in the measured acidity and ionic components were also performed using the linear regression method. The precipitation acidity generally showed a significantly decreasing trend, which was compatible with the pattern of the ratio (N $H_4$$^{+}$+C $a^{2+}$)/ (nss-S $O_4$$^{2-}$+N $O_3$$^{[-10]}$ ).).

  • PDF

Effects of Gibberellin Application and Bagging on Ripening and Quality in 'Delaware' Grape Berries (Delaware 포도에서 Gibberellin 처리와 봉지씌우기가 과립의 성숙과 품질에 미치는 영향)

  • 최주수;박영도
    • Journal of Life Science
    • /
    • v.7 no.4
    • /
    • pp.342-346
    • /
    • 1997
  • This experiment was carried out to clarify the effects of gibberellin(GA) aplication and bagging on repeening and quality in 'Delaware' grape berries. Treatments are 4 plots(2X2 factorial experiment); GA, GA+bagging, bagging and control. The clusters were dipped twice in 100 ppm GA with GA treatment : 10 days before and after the full bloom. The results obtained as follows: 1. GA treatment made the seedless grape berry reduced in the fresh weight but it hastened the ripening period about 2 weeks. 2. Total soluble solid(TSS), viscosity and pH value of berry juice increased with maturation. The concentration of TSS and viscosity were higher in GA treatment plot than GA non-treatment. 3. Berry-hardness, titratable acidity and alcohol inslouble solid(AIS) decreased with maturation. Expically berry-hardness and AIS decreased more greatly in GA non-treatment than GA treatment. 4. The concentration of anthocyanin increased with ripening but pectic substance didn't fluctuate nearly. These of anthocyanin and pectin were higher in GA non-treatment plot than GA treatment. 5. By analysis of factorial experiment GA treatment was highly significant with the $^{o}$Brix/Acidity ratio, juice viscosity and AIS, but high negatively, significant with berry-hardness and berry fresh weight. And it was significant with T S S and negatively, titratable acidity. Bagging was significant with $^{o}$Brix/Acidity ratio and AIS content, but negatively, titratable acidity. 6. Qualitative characters were high correlated with the $^{o}$Brix/Acidity ratio in simple correlation but direct effect by the path-coefficient analysis didn't coincide with simple correlation. The direct effect of pH was large and juice viscosity, the next. And that of berry-hardness was negligible but, AIS, small negatively.

  • PDF

Development of Continuous Monitoring System of Acidic Pollutants for The Studies of Their Diffusion in The Atmosphere (대기오염의 확산 연구를 위한 산성 오염물질의 연속 측정법의 개발)

  • Chung, Hyung-Keun;Dasgupta, Purnendu K.;Lee, Dai Woon
    • Analytical Science and Technology
    • /
    • v.5 no.3
    • /
    • pp.269-276
    • /
    • 1992
  • An ion-exchange/conductometric method is applied for the determination of total acidity in simulated atmospheric samples. Non-$H^+$ cations and strong acid anions are enriched by the preconcentrator columns in series and eluted through the corresponding parallel suppressor units. The conductivities from each channel correspond to the concentrations of the resulting ionized species in equivalents per unit volume. The difference is the measure of acidity due to strong acids. With 5-min sampling at a flow rate of 0.3 mL/min, the detection limits for ${NH_4}^+$ and ${SO_4}^{2-}$ are 0.3 and $0.1{\mu}equiv/L$, respectively. The acidity for samples composed of various ions can be determined without significant error, usually less than 5%. The proposed method discriminates against the artifact from the $CO_2$ dissolution. Principles of acidity measurements are also presented.

  • PDF

Changes in Compositions of Liquor Fractions Distilled from Samil-ju with Various Distillation Conditions (증류조건에 따른 삼일주 증류액의 성분변화)

  • Min, Young-Kyoo;Yun, Hyang-Sik;Jeong, Heon-Sang;Jang, Yun-Sik
    • Korean Journal of Food Science and Technology
    • /
    • v.24 no.5
    • /
    • pp.440-446
    • /
    • 1992
  • Samil-ju, the traditional Korean rice wine was brewed and distilled using different columns (unpacked and packed) at different pressure (760, 460, 260 mmHg). Fractions of distillate were collected and analyzed. The sample wine, Samil-ju showed the following compositions; ethanol 14%, total acidity 16.2 g/100 ml, reducing sugar 7.9 mg/ml, total sugar 8.4 mg/ml, acetaldehyde 6 ppm, fusel oil acetaldehyde and ethyl acetate 6 ppm. As distillation proceeds, contents of ethanol, methanol, fusel oil, acetaldehyde and ethyl acetate were decreased but total acidity was increased. Generally at reduced pressure, all the constituents but total acidity showed more decrease than those at atmospheric pressure. In the 1st, 2nd and 3rd fractions of the distillate, ethanol contents were maintained at about 70% but those contents decreased abruptly to below 50% from the 5th fraction. Sixteen sensory characteristics were identified as quality factors of distillate. Among them, four characteristics were identified as aroma properties, seven as tastes and five as aftertastes. Nuruk and cooling flavor were considered as important factors which affect greatly the sensory quality of distillate. Among various fractions, the 2nd, 3rd and 4th fractions obtained from unpacked column at 260 mmHg showed the highest score in the overall quality. The compositions of these fractions were ranged as follows; methanol $24{\sim}36\;ppm$, total acidity $0.21{\sim}0.29\;g/100\;ml$, fusel oil 657-1340 ppm, acetaldehyde $12{\sim}41\;ppm$, and ethylacetate $22{\sim}311\;ppm$, respectively.

  • PDF

Use of Response Surface Methodology for Optimization of Clarified Mixed Apple and Carrot Juice Production (반응표면 분석을 이용한 사과.당근 혼합주스의 청징공정 최적화)

  • Seog, Eun-Ju;Lee, Jun-Ho
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.35 no.8
    • /
    • pp.1051-1056
    • /
    • 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%.

Optimization of Manufacturing Condition and Physicochemical Properties for Mixing Beverage added Extract of Elaeagnus multiflora Thunb. Fruits (뜰보리수 추출물을 첨가한 혼합음료 이화학적 특성과 제조조건의 최적화)

  • Hong, Ju-Yeon;Cha, Hyun-Shik;Shin, Seung-Ryeul;Jeong, Yong-Jin;Youn, Kwang-Sup;Kim, Mi-Hyun;Kim, Nam-Woo
    • Korean Journal of Food Preservation
    • /
    • v.14 no.3
    • /
    • pp.269-275
    • /
    • 2007
  • This paper was study to develop an extract of Elaeagnus multiflora as a beverage component, and was part of a broader research project for at the development of processed foods using extract of Elaeagnus multiflora. Acceptable mixing properties of the beverage were significantly related to brix values, pH, total acidity, and total phenol contents. When brown rice vinegar was used as a supplement, the vinegar contributed only 1% of total acidity content, and the brix was below 5% of acceptable level. Maximal total acidity of the mixed beverage was attained which added 19.2%(v/v) of Elaeagnus multiflora extract and 7.6%(v/v) of brown rice vinegar. The mixed beverage contributed 0.88% of the total acidity content. The maximum condition of brix(11.5) of the mixed beverage was arrived to 24.7%(v/v) of Elaeagnus multiflora extract and 4.9%(v/v) of brown rice vinegar. The maximum polyphenol contents of beverage(14.47 mg%) was achieved which added 25.0%(v/v) of Elaeagnus multiflora extract and 4.3%(v/v) of brown rice vinegar.

The Properties of Blanching and Brining in Hot Solution and Trehalose Treatment on the Quality of Cucumber Kimchi during Fermentation (데침과 열수의 침적과 Trehalose 처리가 오이 물김치의 저장중 품질에 미치는 영향)

  • 이혜정
    • The Korean Journal of Food And Nutrition
    • /
    • v.14 no.4
    • /
    • pp.333-338
    • /
    • 2001
  • In research. which Korean pickled cucumber was treated wish various methods, including blanching. brining in hot solution, and treating with trehalose. I examined the changes of properties of material. The Korean pickled cucumber were fermented 4∼5$^{\circ}C$ for 42 days in 1% salt solution. The physiochemical properties were pH, total acidity, total cell count, lactic acid bacteria and texture properties were also evaluated. The result showed that the effect of blanching and soaking cucumber in 100$^{\circ}C$ hot salt solution significantly reduced the softening rate of texture while a rather rapid fermentation was found for those preserved with salt. The effect of trehalose treatment inhenced fermentation but it was significantly reduced softening rate of texture. The texture evaluation of Korean pickled cucumber was found that heat treatment with blanching after soaked in hot solution and trehalose treatment had a positive effect for reduction of softening of cucumber tissue.

  • PDF