• Title, Summary, Keyword: Maillard

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Downstream Process for the Production of Yeast Extract Using Brewer's Yeast Cells

  • In Man-Jin;Kim Dong Chung;Chae Hee Jeong
    • Biotechnology and Bioprocess Engineering:BBE
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    • v.10 no.1
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    • pp.85-90
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    • 2005
  • A downstream process was developed for the production of yeast extract from brewer's yeast cells. Various downstream processing conditions including clarification, debittering, and the Maillard reaction were considered in the development of the process. This simple and economic clarification process used flocculating agents, specifically calcium chloride ($1\%$). After the clarification step, a Maillard reaction is initiated as a flavor-enhancing step. By investigating the effects of several operation parameters, including the type of sugar added, sugar dosage, glycine addition, and temperature, on the degree of browning (DB), giucose addition and reaction temperature were found to have significant effects on DB. A synthetic adsorption resin (HP20) was used for the debittering process, which induced a compositional change of the hydrophobic amino acids in the yeast hydrolysate, thereby reducing the bitter taste. The overall dry matter yield and protein yield for the entire process, including the downstream process proposed for the production of brewer's yeast extract were 50 and $50\%$, respectively.

Effects of the Preheating Treatments of Raw Ginseng in the Model System on the Synthesis of the Maillard Type-Browning Reaction Products of Red Ginseng

  • Suzuki, Yukio;Choi, Kang-Ju;Uchida, Kei;Ko, Sung-Ryong
    • Journal of Ginseng Research
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    • v.28 no.3
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    • pp.136-142
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    • 2004
  • During our investigations on the relationship between the browning reaction of ginseng root and two compounds (arginyl-fructosyl-glucose and arginyl-fructose) in the model system of steaming and heat-drying processes for the preparation of red ginseng, the preheating treatment of main roots of raw ginseng at 60∼70$^{\circ}C$ prior to the steaming and heat-drying processes was found to bring about the gelatinization of starch granules. The enzymatic hydrolysis of gelatinized starch to maltose, a marked formation of maltose, and the increase of both free arginine and total amino acids, resulting the acceleration of the Maillard type-browning reaction of ginseng root during the steaming and heat-drying processes, and the rise of brown color intensity of red ginseng. These results show that the preheating treatment may be effective for the decrease of inside white of red ginseng.

Influence of Sulfur Fertilization on the Antioxidant Activities of Onion Juices Prepared by Thermal Treatment

  • Koh, Eunmi;Surh, Jeonghee
    • Preventive Nutrition and Food Science
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    • v.21 no.2
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    • pp.160-164
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    • 2016
  • Two onions (Sulfur-1 and Sulfur-4) cultivated with different sulfur applications were thermally processed to elucidate the effects of heat treatment on browning index and antioxidant activity. Sulfur-4 onion had higher sulfur content compared with the Sulfur-1 onion. After thermal processing, browning intensity was different between the two onions juices, with lower values observed for Sulfur-4 onion juice. This suggests that sulfur inhibits the Maillard browning reaction. The total reducing capacity of the juices increased at higher thermal processing temperatures; however, it was also lower in the Sulfur-4 onion juice. This suggests that the heat treatment of onions enhanced their antioxidant activity, but the effect was offset in the Sulfur-4 onion juice presumably due to higher sulfur content. This study indicates that sulfur, a core element for the functionality of onions, can decrease the antioxidant activity of thermally processed onions because of its potential as a Maillard reaction inhibitor.

Volatiles from the Maillard Reaction of L-Ascorbic Acid and L-Alanine at Different pHs

  • Yu, Ai-Nong;Deng, Qi-Hui
    • Food Science and Biotechnology
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    • v.18 no.6
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    • pp.1495-1499
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    • 2009
  • The volatiles formed from the reactions of L-ascorbic acid with L-alanine at 5 different pH (5, 6, 7, 8, or 9) and $140{\pm}2^{\circ}C$ for 2 hr was performed using solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) analysis were identified to be 25 different kinds. The reaction between L-ascorbic acid and L-alanine led mainly to the formation of pyrazines. Many of these were alkylpyrazines, such as 3-ethyl-2,5-dimethylpyrazine, 2,5-dimethylpyrazine, 2-ethyl-5-methylpyrazine, 3,5-diethyl-2-methylpyrazine, methylpyrazine, 2-ethyl-6-methylpyrazine, and 2,3-diethyl-5-methylpyrazine, other compounds identified were furans, phenols, benzoquinones, 2,4,6-trimethylpyridine, and 2-methylbenzoxazole. The studies showed that furans, such as furfural and benzofuran were formed mainly at acidic pH. In contrast, higher pH values could promote the production of pyrazines.

Influence of pH on the Antioxidant Activity of Melanoidins Formed from Different Model Systems of Sugar/Lysine Enantiomers

  • Kim, Ji-Sang;Lee, Young-Soon
    • Food Science and Biotechnology
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    • v.17 no.6
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    • pp.1310-1315
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    • 2008
  • This study was to investigate the influence of pH on the antioxidant activity of melanoidins formed from glucose (Glc) and fructose (Fru) with lysine enantiomers in the Maillard reaction. Melanoidins formed from D-isomers were found to be effective antioxidants in different in vitro assays with regard to the ferrous ion chelating activity, 1, l-diphenyl-2-picryl-hydrazil (DPPH) radical scavenging activities, ferric reducing/antioxidant power (FRAP), and 2,2'-azinobis(3-ethylbenothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging activity. In particular, the chelating activity of these melanoidins at a pH of 7.0 was greater than those with pH of 4.0 and 10.0. The chelating activity and DPPH radical scavenging activity of the melanoidins formed from the Glc systems were higher than those of the melanoidins formed from the Fru systems. However, the FRAP and ABTS radical scavenging activity of these melanoidins were not different according to pH level, with exceptions being the Fru systems.

Changes in Physicochemical Properties of Soybean Protein due to Acetylation during Incubation with Glucose

  • Kim, Myung-Hee;Kim, Jin-Hee;Kim, Kang-Sung
    • Journal of Environmental Health Sciences
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    • v.30 no.4
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    • pp.308-313
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    • 2004
  • Native and acetylated soybean protein with acetylation percentage of $25\%$ were incubated with glucose to induce Maillard reaction. Acetylation of ${\varepsilon}$-amino group of lysine residues changed the conformation of soybean protein. The direct uv spectrum of native and acetylated soybean protein showed conformational changes with accessibility of tyrosine and tryptophan residues increased. Acetylation suppressed Maillard reaction between soybean protein and glucose. Acetylated soybean protein showed improved water sorption, fat binding, foam formation, and emulsion activity of the protein, but depressed brown pigment development and trypsin digestion. Thus aceylation prevented deterioration of certain functional characteristics that occurred during storage, besides causing functional characteristics to be improved on its own.

Emulsion Properties of Casein-Alginate Mixtures (카제인-알긴산 혼합물의 유화특성)

  • 황재관;최문정;김종태
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.26 no.6
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    • pp.1102-1108
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    • 1997
  • Proteins and polysaccharides confer distinct functional properties in food systems. This research was attempted to improve emulsion properties of casein by protein-polysaccharide conjugation, in which alginates with various molecular weights were employed as polysaccharide sources. Casein-alginate mixtures were conjugated by the amino-carbonyl or Maillard reaction at 6$0^{\circ}C$ and 79% relative humidity. The resulting casein-alginate conjugates were tested for their emulsion activity and emulsion stabilizing properties. In general, the emulsion stability of casein-alginate mixture greatly increased due to the amino-carbonyl reaction between casein and alginates, whose magnitude depended on the molecular weight of alginate, weight ratio of casein to alginate and incubation time. It was also found that thermal stability and pH stability were markedly improved by the casein-alginate conjugation.

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Changes in the Chemical Properties of Maillard Reaction Products as Affected by Ozonolysis (Maillard 반응생성물의 Ozonolysis에 따른 화학적 특성 변화)

  • 권중호;이기동
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.26 no.6
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    • pp.1122-1127
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    • 1997
  • Melanoidins, which were higher polymers with intense brown color, were investigated on their decolorization and degradation by ozonolysis. Amino acids linked up with melanoidins were readily separated by depolymerization of melanoidins with ozonolysis. The IR spectra of ozone-untreated MRPs showed a higher peak at $1665cm^{-1}$ (C=N) and $1600cm^{-1}$ (C=C) than the corresponding peaks of ozone-treated MRPs. Ozone-treated melanoidins with molecular weight of above 900 showed the highest nitrogen composition of all melanoidins tested. Ozone-treated melanoidins with molecular weight of 900 to 1000 were separated into five peaks on recycling preparative HPLC chromatogram. Major functional groups in ozone-treated melanoidins with molecular weight of 900 to 1, 000 were -CH$_2$-CO-, -CH$_2$-O- and CH$_2$-.

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Maillard Reaction Products Formed from D-Glucose-Glycine, System and Their Formation Mechanism (D-Glucose-Glycine 계의 Maillard 반응생성물 및 그 생성기구)

  • KIM Seon-Bong;PARK Yeung-Ho
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.19 no.1
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    • pp.45-51
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    • 1986
  • Equimolar aqueous solutions of D-glucose and glycine were heated at $50^{\circ}C\;and\;95^{\circ}C$ at pH 6.7. The headspace volatiles and the ether extracts from the reaction mixture were analyzed by gas chromatography and gas chromatography-mass spectrometry using a fused silica capillary column. The major components formed were identified as diacetyl, three furfurals, two pyrroles, one furanone, two pyranones and two amides. In order to elucidate the formation mechanisms of the amides formed front amino-carbonyl reaction, two model systems were adopted. N-butylacetamide were formed as major components from diacetyl-butylamine ana glyoxal-butylamine systems, respectively. The results obtained suggest that such ${\alpha}-dicarbonyls$ as 3-deoxy-D-erythro-2,3-hexodiulose and diacetyl generated in the amino-carbonyl reaction react with amino compounds, amides then being formed by cleavage of the C-C bond in the ${\alpha}-dicarbonyls$.

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Glucose Content and pH of Broiler and Porcine Blood Plasma by Glucose Oxidase or Baker's Yeast Addition (Glucose Oxidase 및 제빵용 효모 첨가에 따른 육계와 돼지의 혈장 포도당과 pH 변화)

  • Lee, Jae-Jun;Yi, Young-Hyoun
    • Korean Journal of Food Science and Technology
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    • v.31 no.2
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    • pp.416-420
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    • 1999
  • The effects of GOD and yeast on glucose content and pH of broiler and porcine blood plasma were investigated. The initial glucose concentration of broiler and porcine blood plasma were $150mg/100cm^{3}\;and\;143mg/100cm^{3}$, respectively. Addition of GOD and yeast decreased glucose contents in broiler and porcine plasma. As expected, plasma glucose content decreased as incubation time increased. While 1080 and 1110 min were required to remove glucose from both broiler and porcine plasma at GOD 5 units/g and 480 and 1020 min were required at GOD 10 units/g, respectively; both required 240 min at 0.3% yeast (w/w). The Maillard reaction can be prevented by desugarization. During the removal of glucose, pH of the plasma decreased. As glucose content in plasma leveled off, the pH value of plasma increased. Therefore, pH may be used as an index of desugarization.

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