• Title/Summary/Keyword: changes of water contents

Search Result 760, Processing Time 0.034 seconds

Changes in the Physicochemical Properties and Functional Components of Uncooked Foods Treated with Electrolyzed Water

  • Jin, Tie-Van;Oh, Deog-Hwan;Eun, Jong-Bang
    • Food Science and Biotechnology
    • /
    • v.17 no.1
    • /
    • pp.72-79
    • /
    • 2008
  • In this study, changes in the physicochemical properties and functional components of uncooked foods, including carrots, cabbage, shiitake (Lentinus edodes) and white button (Agaricus bisporus) mushrooms, sea mustard, and laver treated with electrolyzed water were investigated. No changes were observed in the primary compositions of any of the materials that were hot air- or freeze-dried after being treated with electrolyzed water. The lightness (L), redness (a), and yellowness (b) values of the carrots, shiitake, and laver were not affected by drying, while changes did occur in the cabbage (L-, a-, and b-values), mushrooms (a-value), and sea mustard (b-value) specimens that were hot air- or freeze-dried following the treatments with electrolyzed water. The dietary fiber contents of all the materials increased when they were hot air-dried. Vitamin C content decreased when the samples were treated with alkalic electrolyzed water. No changes occurred in the lectin, $\beta$-carotene, or total phenolic compound contents after the electrolyzed water treatments, suggesting that electrolyzed water could be used effectively as a pasteurization step for uncooked carrots, cabbage, shiitake and white button mushrooms, sea mustard, and laver.

The changes of pectic substances of $emph{Kimchis}$ with different garlic contents during the fermentation periods (마늘첨가량을 달리한 김치의 펙틴질의 변화)

  • 유은주;신말식;전덕영;홍윤호;임현숙
    • Korean journal of food and cookery science
    • /
    • v.4 no.1
    • /
    • pp.59-63
    • /
    • 1988
  • The changes of acidity, the content of alcohol-insoluble solid (AIS) and pectic substances of Kimchis which were prepared with various garlic contents and fermentation at $21^{\circ}C$ were investigated. Acidity and the content of water soluble pectin of Kimchis increased but the content of AIS and protopectin decreased during the fermentation. As the Kimchis contained high garlic contents compared with the Kimchis deleted garlic, acidity of those rapidly increased but the content of AIS of those slightly decreased with fermentation. In the case of Kimcltis contained high garlic contents, protopectin decreased and water soluble pectin increased with fermentation, but the amount of changes was small.

  • PDF

Relationship between Water Content and Osmotic Potential of Lentinula edodes

  • Koo, Chang-Duck;Cho, Sun-Young
    • Mycobiology
    • /
    • v.36 no.1
    • /
    • pp.24-27
    • /
    • 2008
  • This study was conducted to understand how osmotic potentials in Lentinula edodes tissues are related to water contents and how they change while a mushroom matures. Water content and osmotic potential of L. edodes mushroom tissues from log cultivation and sawdust cultivation were measured and the relationships were analyzed. Osmotic potentials in the tissues were exponentially proportional to their moisture contents and there were strain differences in the potentials. Strain 290 has lower osmotic potential than strain 302, in the tissues at the same water content. As the mushrooms mature, tissue water content maintained ca 94% in head tissues and ca 90% in gills, but significantly decreased from ca 90% to 82% in the stipe tissues. Osmotic potential changes were similar to the tissue water content changes as the mushrooms mature. While osmotic potentials maintained -0.25 to -0.45 MPa in head and gill tissues, the potentials greatly decreased from -0.65 to -1.33 MPa in stipe tissues. Our results show that osmotic potentials in L. edodes tissues are exponentially proportional to tissue water contents, that strains differ in osmotic potential related to water, and that stipe tissues can still have nutritional value when they mature.

Qualities of Concrete Using Recycling Water with the Kinds and Contents of Saccaric Based Stabilizing Agent (당류계 안정화제 종류 및 혼입률 변화에 따른 회수수사용 콘크리트의 품질특성)

  • Jin, Hu-Lin;Kim, Kyung-Min;Woo, Jong-Wan;Han, Min-Cheol;Han, Cheon-Goo
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2004.05a
    • /
    • pp.660-663
    • /
    • 2004
  • This paper investigate the qualities variety of concrete using recycling water under various kinds and contents of saccaric based stabilizing agent(SSA). Fluidity had little changes with the kinds and contents of SSA. Air contents of concrete with recycled water only shows the tendency. With an increase in SSA contents, air content recovered. For bleeding properties, bleeding shows to be decreased with an increase in SSA contents. The use of recycled water accelerated the setting time. However, with an increase in SSA, setting time showed the similar level of plain concrete. SSA (Btype) had better performance in enhancing compressive strength owing to loss of air content. Although the use of recycled water increased the drying shrinkage compared with that of plain concrete, it tended to decrease with an increase in SSA.

  • PDF

Changes in the Riboflavin Content of Spinach Salad and Sesame Leaf Salad with Various Cooking and Holding Process in Foodservice Institutions (단체급식소에서 제공되는 시금치 나물과 깻잎 나물의 생산단계 및 보관단계에 따른 리보플라빈 함량 변화(II))

  • 김혜영;박화연
    • Korean journal of food and cookery science
    • /
    • v.20 no.1
    • /
    • pp.34-41
    • /
    • 2004
  • The retention rate of riboflavin in two cooked vegetable salads (spinach salad and sesame leaf salad) were examined at every cooking stage, holding temperature and holding time, with various cooking methods, and a better food preparation method developed. The riboflavin contents of the samples were analyzed by HPLC, with fluoresence detection. The changes in the pH and water contents of the samples were measured during the holding stage at various temperatures and times. There were significant differences in the riboflavin contents during the various preparation and cooking processes, such as trimming, washing, boiling and parching etc. The retention rates of the riboflavin with the various holding methods and cooking temperature were also significantly different. The boiling process caused large losses of riboflavin: in the cases of spinach salad and sesame leaf salad these were 78% and 52% respectively. The pH and water contents showed faster change during 0-6 hours than during 6-12 hours.

Changes in Flavor Components during Ripening of Fermented Sausages (발효소시지의 숙성에 따른 풍미성분의 변화)

  • 양종범
    • The Korean Journal of Food And Nutrition
    • /
    • v.12 no.4
    • /
    • pp.380-386
    • /
    • 1999
  • Fermented sausages inoculated with starter cultures which were combined Lactobacillus curvatus and Staphylococcus carnosus(LCSC), Lactobacillus plantarum and Staphylococcus carnosus(LPSC) were manufac-tured. changes in chemical composition salinity weight loss fatty acids inosine monophosphate(IMP) and hypoxanthine (Hx) and fee amino acids during ripening of fermented sausages were investigated. Due to drying the water content was decreased while the protein and fat contents salinity and weight low were increased during ripening. No significant differences between LCSC and LPSC were found for chemical composition salinity and weight loss. During ripening unsaturated fatty acid contents was dec-reased while saturated fatty acid contents was increased. At the end of the ripening the levels of mon-oenes were slightly higher in the LPSC than in the LCSC. In both treatments IMP contents were dec-reased but no changes were observed in Hx contents during ripening. Due to ripening the increase in total and individual free amino acids were observed and contents of glutamic acid alanine leucine and lysine were greatly increased.

  • PDF

Thaw consolidation behavior of frozen soft clay with calcium chloride

  • Wang, Songhe;Wang, Qinze;Xu, Jian;Ding, Jiulong;Qi, Jilin;Yang, Yugui;Liu, Fengyin
    • Geomechanics and Engineering
    • /
    • v.18 no.2
    • /
    • pp.189-203
    • /
    • 2019
  • Brine leakage is a common phenomenon during construction facilitated by artificial freezing technique, threatening the stability of frozen wall due to the continual thawing of already frozen domain. This paper takes the frequently encountered soft clay in Wujiang District as the study object, and remolded specimens were prepared by mixing calcium chloride solutions at five levels of concentration. Both the deformation and pore water pressure of frozen specimens during thawing were investigated by two-stage loading tests. Three sections were noted from the changes in the strain rate of specimens during thawing at the first-stage load, i.e., instantaneous, attenuated, and quasi-stable sections. During the second-stage loading, the deformation of post-thawed soils is closely correlated with the dissipation of pore water pressure. Two characteristic indexes were obtained including thaw-settlement coefficient and critical water content. The critical water content increases positively with salt content. The higher water content of soil leads to a larger thaw-settlement coefficient, especially at higher salt contents, based on which an empirical equation was proposed and verified. The normalized pore water pressure during thawing was found to dissipate slower at higher salt contents, with a longer duration to stabilize. Three physical indexes were experimentally determined such as freezing point, heat conductivity and water permeability. The freezing point decreases at higher salt contents, especially as more water is involved, like the changes in heat conductivity. The water permeability maintains within the same order at the considered range of salt contents, like the development of the coefficient of consolidation. The variation of the pore volume distribution also accounts for this.

Changes in Physicochemical and Sensory Properties of Fruits as Affected by Chlorine Sterilization (과일류의 염소 소독 방법에 따른 이화학적 및 관능적 품질 특성 변화)

  • Park, Jong-Sook;Nam, Eun-Sook;Park, Shin-In
    • The Korean Journal of Food And Nutrition
    • /
    • v.21 no.4
    • /
    • pp.499-509
    • /
    • 2008
  • The purpose of this study was to investigate the changes in physicochemical and sensory properties of raw fruits during washing and chlorine treatments. Strawberry and banana were pre-prepared at different concentration of chlorinated water(0 ppm, 50 ppm and 100 ppm), immersion time(3 min and 5 min), and number of post-rinsing(1 time, 2 times and 3 times). The physicochemical properties such as pH, sugar contents, residual chlorine contents, color values and hardness of the fruits were analyzed, and the sensory quality were evaluated throughout the sterilization treatment process. After washing strawberry with 100 ppm chlorinated water and 3 times of post-rinsing, pH and residual chlorine contents were showed a little difference, while sugar contents, hardness, and color values(L, a and b) were reduced. In case of banana, pH, sugar contents and residual chlorine contents were not affected, and hardness and L color value were reduced. However, a and b color values of banana were gradually increased as the development of brown discoloration. Sensory properties of the samples were affected by the chlorine sterilization treatment. In overall acceptance, strawberry and banana treated with 100 ppm chlorinated water showed the lowest scores among treatments. Therefore it could be suggested that the application of 50 ppm chlorinated water for $3{\sim}5$ minutes with over 3 times of post-rinsing was the effective pre-preparation method without affecting the quality of the fruits.

Postmortem Changes in the Physico-Chemical Characteristics of Korean Native Chicken (저장기간에 따른 한국산 토종닭고기의 품질 특성)

  • 성삼경;권연주;김대곤
    • Korean Journal of Poultry Science
    • /
    • v.25 no.2
    • /
    • pp.55-64
    • /
    • 1998
  • This study was carried out to investigate the postmortem changes in physico-chemical characteristics of chicken meat with different breeds. Thigh and breast meats from Korean Native Chicken(KNC, 15-wk old), Wangchoo(15-wk old), and broiler(7-wk old) were stored at 5 ˚C. Differences in postmortem pH changes were not recognized among breeds, and pH showed by the lowest value at the 1st day of postmortem in all breeds. Breast meat had tendency to drop pH faster than thigh meat. Heme pigment contents showed no differences among breeds. KNC showed the lowest cholesterol contents in all breeds, total collagen contents showed the lowest value at the 1st day of postmortem, and thereafter it was gradually increased. Heat soluble collagen contents was lowest in Wangchoo. Water soluble and salt soluble protein showed the lowest extractability at the 1st day of storage. Broiler showed the highest extractability of these proteins and Wangchoo showed the lowest. Water holding capacity(WHC) had increasing tendency whilst cooking loss had decreasing tendency by the ageing. WHC of breast and thigh meat showed the highest values in KNC and broiler, respectively. Myofibrillar fragmentation index (MFI) was significantly increased in all breeds by the ageing. Breast and thigh meat showed almost same MFI in KNC and broiler, and in KNC and Wangchoo, respectively. Hardness of breast meat showed decreasing tendency by the ageing.

  • PDF

The Correlation Study on the Desorption Enthalpy Changes of Sun- Cured Tobacco (향끽미종 잎담배의 탈착 엔탈피 변화에 관한 상관성 연구)

  • 최승찬
    • Journal of the Korean Society of Tobacco Science
    • /
    • v.6 no.1
    • /
    • pp.33-37
    • /
    • 1984
  • The net enthalpy changes for the water desorption of sun-cured tobacco have been studied. In order to compare the values of net enthalpy changes for the samples at the same moisture contents, correlation analyses have been performed. The results are summarizing as followings : 1 . As temperature and water vapor pressure increased, equlibrium moisture content were approaching to the saturated vapor pressure of water. 2. The values of 1nP against the reciprocal of absolute temperature were linear for the water desorption of samples. 3. Multiple regression was analyzed to calculate the values of 1nP at the same moisture content. The significance of $x^2$-test for the multiple regression was 0.5%. 4. The values of net enthalpy changes for Basma were greater than those of Sohyang at the same moisture content.

  • PDF