• Title/Summary/Keyword: Physicochemical changes

Search Result 918, Processing Time 0.029 seconds

Effects of the Addition of Ecklonia cava Powder on the Selected Physicochemical and Sensory Quality of White Pan Bread

  • Lee, Jun Ho;Choi, Dong Won
    • Preventive Nutrition and Food Science
    • /
    • v.18 no.4
    • /
    • pp.287-291
    • /
    • 2013
  • Physicochemical properties and consumer perception of white pan bread as influenced by the addition of Ecklonia cava powder (ECP) were investigated. Freeze-dried Ecklonia cava were ground, sieved through a laboratory sieve and a fraction with particles less than $250{\mu}m$ was used. Amount of ECP added (0~3%) to the bread was found to affect the bread quality significantly (P<0.05). pH, bread height, and volume of the control was significantly higher than others (P<0.05) and decreased significantly (P<0.05) with the addition of ECP. Moisture content showed no significant differences (P>0.05). There were distinctive color changes with the addition of the powder: $L^*$- and $a^*$-values decreased but $b^*$-value increased significantly (P<0.05). The hardness of bread was found to increase but both cohesiveness and springiness showed a reverse trend with the addition of the powder. Consumer acceptance test indicated that ECP content 1% on wheat flour could be the recommended supplementation level for the consumers without sacrificing sensory quality.

Effects of Humic Acids on Growth of Herbaceous Plants in Soil Contaminated with High Concentration of Petroleum Hydrocarbons and Heavy Metals (고농도 유류와 중금속으로 복합 오염된 토양에서 식물성장에 미치는 부식산의 영향)

  • Kim, Ki-Seob;Sung, Ki-June
    • Journal of Soil and Groundwater Environment
    • /
    • v.16 no.1
    • /
    • pp.51-61
    • /
    • 2011
  • Germination tests were conducted to determine the practical concentration levels at which plants can reproduce naturally during the phytoremediation of soils contaminated with a high concentration of petroleum hydrocarbons and heavy metals. The effects of humic acids on plant growth and soil physicochemical properties were also investigated. The results show that phytoremediation can be applied in soils contaminated by multiple contaminants at the former soil contamination potential level of Korean soil quality standards considering successful natural reproduction. It was observed that germination rates of Helianthus annuus and Festuca arundinacea were high after all treatments, and transplantation was more appropriate for Phragmites communis in phytoremediation. Humic acids had a positive effect on the growth of both aboveground and belowground biomass of herbaceous plants. Growth inhibition by multiple contaminants is more severe in the case of aboveground biomass. Germination and growth tests suggest that Helianthus annuus is a suitable phytoremediation plant for soils contaminated with a high concentration of petroleum hydrocarbons and heavy metals. The addition of humic acids also caused changes in the physicochemical properties of contaminated soils. An increase in the carbon and nitrogen content due to the addition of humic acids and a correlation between cation exchange capacity(CEC) and the organic matter content were observed.

Effects of Ionizing Energy and Ozone Treatments on the Microbial Decontamination and Physicochemical Properties of Aloe Powders and Bee Pollen

  • Yook, Hong-Sun;Chung, Young-Jin;Kim, Jung-Ok;Kwon, Oh-Jin;Kim, Sung;Byun, Myung-Woo
    • Preventive Nutrition and Food Science
    • /
    • v.2 no.2
    • /
    • pp.89-95
    • /
    • 1997
  • The comparative effects of gamma irradiation an ozone treatment on the microbiological and physicochemical qualities were investigated for the improvement of hygienic quality of aloe powder and bee pollen. Gamma irradiation at 7.5~10kGy could reduce total aerobic bacteria, molds and coliforms below detection levels, but ozone treatment up to 18 ppm for 8hr was not sufficient to eliminate the microorganisms from aloe powder and bee pollen. The physicochemical properties such as fatty acid an amino acid compositions, mineral content, TBA value, barbaloin and pigment contents were not significantly changed by gamma irradiation, whereas ozone treatment caused significant changes in fatty acid composition, lipid oxidation and destruction of barbaloin and natural pigments.

  • PDF

ROLE OF SOILS IN THE DISPOSAL OF NUCLEAR WASTE

  • Lee, S.Y.
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.19 no.3
    • /
    • pp.251-268
    • /
    • 1986
  • Selecting a site for the safe disposal of radioactive waste requires the evaluation of a wide range of geologic, mineralogic, hydrologic, and physicochemical properties. Although highly diverse, these properties are in fact interrelated. Site requirements are also diverse because they are influenced by the nature of the radionuclides in the waste, for example, their half-lives, specific energy, and chemistry. A fundamental consideration in site selection is the mineralogy of the host rock, and one of the most ubiquitous mineral groups is clay minerals. Clays and clay minerals as in situ lithologic components and engineered barriers may playa significant role in retarding the migration of radionuclides. Their high sorptivity, longevity (stability), low permeability, and other physical factors should make them a very effective retainer of most radionuclides in nuclear wastes. There are, however, some unanswered questions. For example, how will their longevity and physicochemical properties be influenced by such factors as radionuclide concentration, radiation intensity, elevated temperatures, changes in redox condition, pH, and formation fluids for extended periods of time? Understanding of mechanisms affecting clay mineral-radionuclide interactions under prevailing geochemical conditions is important; however, the utilization of experimental geochemical information related to physicochemical properties of clays and clay-bearing materials with geohydrologic models presents a uniquely challenging problem in that many assessments have to be based on model predictions rather than on experiments. These are high-priority research investigations that need to be addressed before complete reliance for disposal area performance is made on clays and clay minerals.

  • PDF

Physicochemical Property Changes of Sweet Potato Starch by Ultra Fine Pulverization

  • Kim, Hee-Sun;Park, Hye-Young;Han, Gwi-Jung;Kim, Myung-Hwan
    • Food Engineering Progress
    • /
    • v.15 no.2
    • /
    • pp.169-174
    • /
    • 2011
  • This study was performed to analyze the effects of ultra fine pulverization (UFP) on the physicochemical properties of sweet potato starch (SPS). The average diameter and specific surface area of the SPS was decreased from 22.94 to 10.25 $\mu$m and from 0.879 to 1.909 $m^2$ /g throughout UFP, respectively, and the damaged starch content was increased from 13.7 to 99.2%. The pulverized sweet potato starch (PSPS) had higher swelling power, solubility, and transmittance values than the SPS. X-ray diffractograms revealed that the SPS had a C-type pattern, which disappeared in PSPS. The rapid visco analysis (RVA) characteristics, peak viscosity, break down, and set back of SPS ceased to exist in PSPS. According to differential scanning calorimetry (DSC) curves, the peak temperature ($T_p$) and gelatinization enthalpy ($\Delta$E) of SPS were $71.95^{\circ}C$ and 10.40 J/g, respectively, while these remained undetected in PSPS. The enzymatic digestibilities of SPS and PSPS were 61.7 and 84.7%, respectively.

Changes in Physicochemical Attributes of Potato Slices with Different Cultivars during Cold Storage (품종별 한국산 감자 슬라이스의 냉장 중 이화학적 품질의 변화)

  • Chung, Hyoun-Mi;Lee, Gui-Ju
    • Journal of the Korean Society of Food Culture
    • /
    • v.10 no.2
    • /
    • pp.97-100
    • /
    • 1995
  • Three potato cultivars were prepared as slices and stored for 4 weeks at $5^{\circ}C$. Changes in Vitamin C content and other quality factors, such as color, pH, soluble solid and protein content were determined. Vitamin C content and L value decreased in three potato cultivars. Initial Vitamin C contents of three potato cultivars varied from 49.27 mg% in Sumi to 56.40 mg% in Namjak. Changes in L value showed that the tendency of browning in Daejima was slower than Sumi and Namjak. Changes in pH were small. Soluble solids and protein content increased and varied by cultivar. From the correlation analysis, correlation between browning degree and Vitamin C content was low in three potato cultivars.

  • PDF

Development of sea water cooling apparatus for fish hold storage (어창용 해수 냉각장치 개발에 관한 연구)

  • 조영제
    • Journal of the Korean Society of Fisheries and Ocean Technology
    • /
    • v.35 no.1
    • /
    • pp.60-64
    • /
    • 1999
  • The objective of this study was to manufacture the sea water cooling apparatus for fish hold storage to extend the freshness of fish. Using the sea water cooling apparatus manufactured, it makes observations on the physicochemical and sensual properties of mackerel such as ATP and its related compounds, K-value, VBN, TMA, TBA, salt-concentration and skin color through storage. The results of this investigation showed that the values of physicochemical properties such as ATP and its related compounds, K-value, VBN, TMA, TBA increased gradually during storage in sea water cooling apparatus manufactured and the changes of skin color was inhibited also. From these results, it could be suggested that developed sea water cooling apparatus is effective in shelf-life extension of fishes.

  • PDF

A Review on the Change of Physicochemical Quality during Heating of Milk (열처리에 의한 우유의 이화학적 품질변화에 관한 고찰)

  • Jung, In-Gyeong;In, Yeong-Min
    • Journal of Dairy Science and Biotechnology
    • /
    • v.19 no.1
    • /
    • pp.13-21
    • /
    • 2001
  • Milk can be regarded as a complete food, containing protein, fat, lactose, vitamins and minerals. Milk is heated for a variety of reasons. The main reasons are: to remove pathogenic organisms; to increase shelf-life. But, when milk is heated, many changes take place: denaturation of whey proteins and interaction with casein, Maillard browning, losses of vitamin and minerals. The addition of a additive and milk powder to flavor and taste may cause undesirable change of quality during heating milk. The reconstituted milk is the milk product resulting from the addition of water to the dried or condensed form in the amount necessary to re-establish the specified water solids ratio. Therefore, according to the increasement of consumption of processed milk, the necessity for study about the quality of processed milk mixed with reconstituted milk arose.

  • PDF

Volatile Compound, Physicochemical, and Antioxidant Properties of Beany Flavor-Removed Soy Protein Isolate Hydrolyzates Obtained from Combined High Temperature Pre-Treatment and Enzymatic Hydrolysis

  • Yoo, Sang-Hun;Chang, Yoon Hyuk
    • Preventive Nutrition and Food Science
    • /
    • v.21 no.4
    • /
    • pp.338-347
    • /
    • 2016
  • The present study investigated the volatile compound, physicochemical, and antioxidant properties of beany flavor-removed soy protein isolate (SPI) hydrolyzates produced by combined high temperature pre-treatment and enzymatic hydrolysis. Without remarkable changes in amino acid composition, reductions of residual lipoxygenase activity and beany flavor-causing volatile compounds such as hexanol, hexanal, and pentanol in SPI were observed after combined heating and enzymatic treatments. The degree of hydrolysis, emulsion capacity and stability, 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity, and superoxide radical scavenging activity of SPI were significantly increased, but the magnitudes of apparent viscosity, consistency index, and dynamic moduli (G', G") of SPI were significantly decreased after the combined heating and enzymatic treatments. Based on these results, it was suggested that the enzymatic hydrolysis in combination with high temperature pre-treatment may allow for the production of beany flavor-removed SPI hydrolyzates with superior emulsifying and antioxidant functionalities.

Effect of Immersion in Refrigerated Brine Solution on Physicochemical Properties of Olive Flounder (Paralichthys olivaceus) Muscle 4. Changes of physicochemical properties in Olive flounder during storage at $5^{\circ}C$

  • Lee, Gi-Bong;Shim, Kil-Bo;Cho, Min-Sung;Kim, Tae-Jin;Cho, Young-Je
    • Proceedings of the Korean Society of Fisheries Technology Conference
    • /
    • 2002.10a
    • /
    • pp.116-117
    • /
    • 2002
  • Olive flounder and Black rockfish comprises around 90% of the total fish culture in Korea. Most of the olive flounder is consumed as raw fish meat “saengseonhoe”, as like a sashimi in Japan. Also, texture is particularly a important factor which determine the quality of raw fish meat in Korea. Many works have attempted to improve of texture such as arai, electrical stimulation and compulsory exercise of fishes. (omitted)

  • PDF