• Title/Summary/Keyword: $N_{2}$ gas

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유청단백질로 만들어진 식품포장재에 관한 연구

  • Kim, Seong-Ju
    • 한국유가공학회:학술대회논문집
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    • 2002.04a
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    • pp.59-60
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    • 2002
  • Edible films such as wax coatings, sugar and chocolate covers, and sausage casings, have been used in food applications for years$^{(1)}$ However, interest in edible films and biodegradable polymers has been renewed due to concerns about the environment, a need to reduce the quantity of disposable packaging, and demand by the consumer for higher quality food products. Edible films can function as secondary packaging materials to enhance food quality and reduce the amount of traditional packaging needed. For example, edible films can serve to enhance food quality by acting as moisture and gas barriers, thus, providing protection to a food product after the primary packaging is opened. Edible films are not meant to replace synthetic packaging materials; instead, they provide the potential as food packagings where traditional synthetic or biodegradable plastics cannot function. For instance, edible films can be used as convenient soluble pouches containing single-servings for products such as instant noodles and soup/seasoning combination. In the food industry, they can be used as ingredient delivery systems for delivering pre-measured ingredients during processing. Edible films also can provide the food processors with a variety of new opportunities for product development and processing. Depends on materials of edible films, they also can be sources of nutritional supplements. Especially, whey proteins have excellent amino acid balance while some edible films resources lack adequate amount of certain amino acids, for example, soy protein is low in methionine and wheat flour is low in lysine$^{(2)}$. Whey proteins have a surplus of the essential amino acid lysine, threonine, methionine and isoleucine. Thus, the idea of using whey protein-based films to individually pack cereal products, which often deficient in these amino acids, become very attractive$^{(3)}$. Whey is a by-product of cheese manufacturing and much of annual production is not utilized$^{(4)}$. Development of edible films from whey protein is one of the ways to recover whey from dairy industry waste. Whey proteins as raw materials of film production can be obtained at inexpensive cost. I hypothesize that it is possible to make whey protein-based edible films with improved moisture barrier properties without significantly altering other properties by producing whey protein/lipid emulsion films and these films will be suitable far food applications. The fellowing are the specific otjectives of this research: 1. Develop whey protein/lipid emulsion edible films and determine their microstructures, barrier (moisture and oxygen) and mechanical (tensile strength and elongation) properties. 2. Study the nature of interactions involved in the formation and stability of the films. 3. Investigate thermal properties, heat sealability, and sealing properties of the films. 4. Demonstrate suitability of their application in foods as packaging materials. Methodologies were developed to produce edible films from whey protein isolate (WPI) and concentrate (WPC), and film-forming procedure was optimized. Lipids, butter fat (BF) and candelilla wax (CW), were added into film-forming solutions to produce whey protein/lipid emulsion edible films. Significant reduction in water vapor and oxygen permeabilities of the films could be achieved upon addition of BF and CW. Mechanical properties were also influenced by the lipid type. Microstructures of the films accounted for the differences in their barrier and mechanical properties. Studies with bond-dissociating agents indicated that disulfide and hydrogen bonds, cooperatively, were the primary forces involved in the formation and stability of whey protein/lipid emulsion films. Contribution of hydrophobic interactions was secondary. Thermal properties of the films were studied using differential scanning calorimetry, and the results were used to optimize heat-sealing conditions for the films. Electron spectroscopy for chemical analysis (ESCA) was used to study the nature of the interfacial interaction of sealed films. All films were heat sealable and showed good seal strengths while the plasticizer type influenced optimum heat-sealing temperatures of the films, 130$^{\circ}$C for sorbitol-plasticized WPI films and 110$^{\circ}$C for glycerol-plasticized WPI films. ESCA spectra showed that the main interactions responsible for the heat-sealed joint of whey protein-based edible films were hydrogen bonds and covalent bonds involving C-0-H and N-C components. Finally, solubility in water, moisture contents, moisture sorption isotherms and sensory attributes (using a trained sensory panel) of the films were determined. Solubility was influenced primarily by the plasticizer in the films, and the higher the plasticizer content, the greater was the solubility of the films in water. Moisture contents of the films showed a strong relationship with moisture sorption isotherm properties of the films. Lower moisture content of the films resulted in lower equilibrium moisture contents at all aw levels. Sensory evaluation of the films revealed that no distinctive odor existed in WPI films. All films tested showed slight sweetness and adhesiveness. Films with lipids were scored as being opaque while films without lipids were scored to be clear. Whey protein/lipid emulsion edible films may be suitable for packaging of powder mix and should be suitable for packaging of non-hygroscopic foods$^{(5,6,7,8,)}$.

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A Comparative Study of Two Different Heel Lancet Devices for Blood Collection in Preterm Infants (미숙아에서 채혈을 위한 발뒤꿈치 천자시 두 종류 천자 기구의 비교)

  • Lim, Hyo-Bin;Rhu, Mi-Joo;Jung, Ji-Mi;Jeon, Ga-Won;Sin, Jong-Beom
    • Neonatal Medicine
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    • v.17 no.2
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    • pp.239-244
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    • 2010
  • Purpose: To evaluate two different heel lancet device in terms of pain response and success of the procedure in the preterm infants undergoing heel puncture. Methods: 100 preterm infants undergoing capillary blood gas analysis or capillary bilirubin monitoring underwent heel puncture, were randomly allocated to blood sampling from the heel with either a conventional manual lancet or an automatic incision device. Primary outcome measures included the Premature Infants Pain Profile (PIPP) score, total duration of procedure, number of heel puncture and number of bruise. The pain response was evaluated using PIPP score and the effectiveness was evaluated using three criteria: total duration of blood sampling, number of puncture, bruising of the heel or ankle. Statistical analysis was performed using the SPSS ver. 13.0 program. Difference between the groups were analysed with t test (continuous variables) and the Chi square test or Fisher test (categorical variables). Results: The mean PIPP score was 4.91 for the automatic lancet group compared with 5.84 for the conventional manual lancet group (P=0.0255).The number of pain scores above 7 during blood collection did not differ between two groups (P=0.2167). The procedure took less time to perform in the automatic lancet group (mean, 30.69 seconds) than in the conventional lancet group (mean, 48.92 seconds) (P<0.0001). Conclusion: This study demonstrated that the automatic lancet device causes less pain and a shorter procedure time than the conventional manual lancet in preterm infants undergoing heel puncture. On the basis of these results the automatic lancet device is very useful method for blood collection in preterm infants by heel puncture.

Comparison of Fragrance and Chemical Composition of Essential Oils in Gom-chewi (Ligularia fischeri) and Handaeri Gom-chewi (Ligularia fischeri var. spicifoprmis) (곰취(Ligularia fischeri)와 한대리곰취(Ligularia fischeri var. spicifoprmis) 정유의 향취 및 향기성분 비교)

  • Yeon, Bo-Ram;Cho, Hae Me;Yun, Mi Sun;Jhoo, Jin-Woo;Jung, Ji Wook;Park, Yu Hwa;Kim, Songmun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.41 no.12
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    • pp.1758-1763
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    • 2012
  • This study was conducted to compare fragrance and volatile chemicals of essential oils in Gom-chewi (Ligularia fischeri) and Handaeri Gom-chewi (Ligularia fischeri var. spicifoprmis). Essential oils were extracted by steam distillation of leaves of Gom-chewi (GC) and Handaeri Gom-chewi (HGC), after which samples were collected by solid-phase micro extraction and the compositions of the essential oils were analyzed by gas chromatography-mass spectrometry (GC-MS). The yields of the essential oils in GC and HGC were 0.12% and 0.04%, respectively, and the threshold levels of the essential oils in GC and HGC were 0.01% and 0.1%, respectively. There were 19 constituents of the essential oil of Gom-chewi: 14 carbohydrates, 4 alcohols, and 1 acetate, and the major constituents were L-${\beta}$-pinene (36.02%), D-limonene (25.64%), ${\alpha}$-pinene (24.85%) and ${\beta}$-phellandrene (5.39%). In the essential oil of HGC, 25 constituents were identified: 17 carbohydrates, 4 alcohols, 3 acetates, and 1 N-containing compound, and the major constituents of HGC were D-limonene (39.74%), L-${\beta}$-pinene (35.43%) and ${\alpha}$-pinene (11.94%). The minor constituents of HGC were ${\rho}$-cymene, ${\gamma}$-muurolene, ${\gamma}$-cadinene, germacrene D, ingol 12-acetate and butyl 9,12,15-octadecatriene and nimorazole were not identified in the GC essential oil. Overall, the results showed that the fragrance and chemical compositions of essential oils in GC and HGC differed, suggesting that both essential oils could be used for the development of perfumery products.

Linolenic Acid in Association with Malate or Fumarate Increased CLA Production and Reduced Methane Generation by Rumen Microbes

  • Li, X.Z.;Choi, S.H.;Jin, G.L.;Yan, C.G.;Long, R.J.;Liang, C.Y.;Song, Man K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.22 no.6
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    • pp.819-826
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    • 2009
  • An in vitro study was conducted to investigate the effect of malate or fumarate on fermentation characteristics, and production of conjugated linoleic acid (CLA) and methane ($CH_4$) by rumen microbes when incubated with linolenic acid (${\alpha}-C_{18:3}$). Sixty milligrams of ${\alpha}-C_{18:3}$ alone (LNA), or ${\alpha}-C_{18:3}$ with 24 mM malic acid (M-LNA) or ${\alpha}-C_{18:3}$ with 24 mM fumaric acid (F-LNA) were added to the 150 ml culture solution consisting of 75 ml strained rumen fluid and 75ml McDougall's artificial saliva. Culture solution for incubation was also made without malate, fumarate and ${\alpha}-C_{18:3}$ (Control). Two grams of feed consisting of 70% concentrate and 30% ground alfalfa (DM basis) were also added to the culture solution of each treatment. In vitro incubation was made anaerobically in a shaking incubator up to 12 h at $39^{\circ}C$. Supplementation of malate (M-LNA) or fumarate (F-LNA) increased pH at 6 h (p<0.01) and 12 h (p<0.001) incubation times compared to control and linolenic acid (LNA) treatments. Both malate and fumarate did not influence the ammonia-N concentration. Concentration of total VFA in culture solution was higher for M-LNA and F-LNA supplementation than for control and LNA treatments from 6 h (p<0.040) to 12 h (p<0.027) incubation times, but was not different between malate and fumarate for all incubation times. Molar proportion of $C_3$ was increased by F-LNA and M-LNA supplementation from 6 h (p<0.0001) to 12 h (p<0.004) incubation times compared to control and LNA treatments. No differences in $C_{3}$ proportion, however, were observed between M-LNA and F-LNA treatments. Accumulated total gas production for 12h incubation was increased (p<0.0002) by M-LNA or F-LNA compared to control or LNA treatment. Accumulated $CH_4$ production for 12 h incubation, however, was greatly reduced (p<0.0002) by supplementing malate or fumarate compared to the control, and its production from M-LNA or F-LNA treatment was smaller than that from LNA treatment. Methane production from LNA, M-LNA or F-LNA treatment was steadily lower (p<0.01 - p<0.001) from 3 h incubation time than that from the control, and was also lower for M-LNA or F-LNA treatment at incubation times of 6 h (p<0.01) and 9 h (p<0.001) than for LNA treatment. Methane production from LNA, however, was reduced (p<0.01 - p<0.001) from 3 h to 9 h incubation times compared to the control. Both malate and fumarate increased concentration of trans11-$C_{18:1}$ from 3 h to 12 h incubation (p<0.01), cis9,trans11-CLA up to 6 h incubation (p<0.01 - p<0.01), trans10,cis12-CLA at 3 h (p<0.05) and 12 h (p<0.01), and total CLA for all incubation times (p<0.05) compared to corresponding values for the ${\alpha}-C_{18:3}$ supplemented treatment (LNA). In conclusion, malate and fumarate rechanneled the metabolic $H_2 pathway to production of propionate and CLA, and depressed the process of biohydrogenation and methane generation. Linolenic acid alone would also be one of the optimistic alternatives to suppress the $CH_4$ generation.

The Effect of the Addition of Carbohydrate Sources on the Concentration of Odorous Compounds for Recycling of Pig Slurry to Grassland (발효탄수화물 첨가 비육돈사료가 초지환원용 슬러리의 악취물질 농도에 미치는 영향)

  • Cho, Sung Back;Hwang, Ok Hwa;Park, Kyu Hyeun;Choi, Dong Yun;Yang, Seung Bong;Kim, Do Hwan;Park, Sung Kwon
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.33 no.4
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    • pp.257-262
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    • 2013
  • This study investigates the effect of fermentable carbohydrate on the concentration of odorous compounds in pig slurry. Four types of pig diet were studied: control, peanut hull (crude fiber 29.87, NDF 44.02%), golden fiber (crude fiber 48.77, NDF 65.88%), and almond hull (crude fiber 44.30, NDF 64.44%). Pigs (average BW 37.0 kg) were fed diets that met the Korean Feeding Standard (2012) and their excreta samples were collected from the slurry pits. Levels of volatile organic compounds (phenols and indoles) and volatile fatty acids were analyzed by gas chromatography. Phenol level was the lowest (p<0.05) in golden fiber (33.26 ppm) group and the highest in control (97.29 ppm). The concentration of indoles in the peanut hull (1.27 ppm), almond hull (1.20 ppm), and golden fiber (1.02 ppm) groups was lower (p < 0.05) than that of control (1.79 ppm). Levels of short chain fatty acid (SCFA) were lower (p < 0.05) in golden fiber (1,319 ppm) and almond hull (1,433 ppm) groups than in control (1,893 ppm). Concentration of branched chain fatty acid (BCFA) in the golden fiber group (74 ppm) was lower (p < 0.05) than that of control (98 ppm). Taken together, the concentration levels of phenols, indoles, and VFAs decreased on addition of peanut hull, golden fiber or almond hull to the diet, suggesting that fermentable carbohydrate may contribute to reducing odorous compounds in pig slurry.