• Korean journal of food and cookery science
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• v.17 no.2
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• pp.117-122
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• 2001

Ground fresh garlic and 50% ethanol garlic extracts were added into ground porks in order to investigate their effects on pH, peroxide and TBA values of ground porks during storage at 4$\^{C}$. The grounded porks tested were devided into two groups of fresh and heated forks at 100$\^{C}$ for 10 minutes. A significant control effect of ground garlic and extracts was found on peroxide and TBA values during storage, particularly for those added with 20% ground garlic and 10% garlic extracts. The effects were maximum after storage of 4-6 days and then decreased thereafter The pH was generally decreased until 6 days followed by the increase. Addition of garlic and garlic extracts caused a little increase in pH and the pH changes were less than the changes of control. Eventhough the effects of garlic on pH, peroxide and TBA values were similar for both heated and fresh pork, heat treated one showed more changes than fresh pork.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.5
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• pp.752-757
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• 1995

The effect of fermentation temperature on the changes of pH, acidity, salt content, color and vitamin C of mustard leaf kimchi during various storage days was investigated. The conditions of fermentation temperature were set at $4^{\circ}C$ (sample A) and $20^{\circ}C$ (sample B), and $4^{\circ}C$ after keeping at $20^{\circ}C$ for 12 hours(sample C) and $20^{\circ}C$ for 36 hours(sample D). As the fermentation proceeded, pH of sample stored at low temperature(sample A) was drop ped gradually from initial pH of 5.24 but there was great pH drop in the sample stored at high temperature(sample B, D). The salt content of the sample B at high temperature increased remarkably, and then the values showed D > A > C. The Humter values of L and a increased at the optimum ripening period, the higher the initial fermentation temperature(B) and the later the initial fermentation time at $20^{\circ}C$ those values, then decreased. The Hunter value of b constantly increased until day of 108. As fermentation time passed, the content of total vitamin C decreased to the range of 9.0mg% to 14.0mg% up to 24 days of fermentation, and at the optimum ripening period, it increased to the range of 14.0mg% to 22.0mg%, and at the fermentation period(until day 108), it decreased gradually.

• Bulletin of the Korean Mathematical Society
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• v.56 no.2
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• pp.333-349
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• 2019

We give explicitly an average value formula under the multiplication-by-2 map for the x-coordinates of the 2-division points D on the Jacobian variety J(C) of a hyperelliptic curve C with genus g if $2D{\equiv}2P-2{\infty}$ (mod Pic(C)) for $P=(x_P,y_P){\in}C$ with $y_P{\neq}0$. Moreover, if g = 2, we give a more explicit formula for D such that $2D{\equiv}P-{\infty}$ (mod Pic(C)).

• Bulletin of the Korean Chemical Society
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• v.21 no.4
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• pp.379-382
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• 2000

The temperature dependence of the kinetic parameters of the aspartase-catalyzed reaction has been examined in the direction of deamination. The pK1values at 37$^{\circ}C$, 25$^{\circ}C$, 16$^{\circ}C$ and 7$^{\circ}C$ were 6.2 $\pm$ 0.1, 6.3 $\pm$ 0.1, $6.7{\pm}0.3$ and 6.9 $\pm$ 0.3, respectively. On the other hand, the pK2 values at 37$^{\circ}C$,25$^{\circ}C$, 16$^{\circ}C$ and 7$^{\circ}C$ were 8.1 $\pm0.2$, 8.3 $\pm$ 0.2, 8.2 $\pm$ 0.3 and 8.0 $\pm$ 0.2,respectively. The enthalpy of ionization, DHion, calculated from the slope of pK1, are 6.0 $\pm$ 0.3 kcal/mol. These results validate the prediction that aspartase requires a histidine residue for a general base, and a cysteine (or having a carboxyl functional group) for a general acid.

• Preventive Nutrition and Food Science
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• v.5 no.3
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• pp.131-135
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• 2000

The inhibitory effect of various organic acids on the growth and survival of Escherichia coli O157:H7 in tryptic soy broth with 0.6% yeast extract at 37$^{\circ}C$ or 4$^{\circ}C$ was determined. Minimal inhibitory pHs of acetic acid, citric acid, fumaric acid, hydrochloric acid and lactic acid were 5.0, 4.0, 4.5, 4.0 and 4.5, respectively. Acetic acid (0.012 m) showed the strongest antimicrobial activity, based on the pH values or equivalent molar concentrations, followed by lactic acid (0.0006 M), fumaric acid (0.004M) and citirc acid (0.004 M), respectively, E. coli O157:H7 with an initial inoculum of {TEX}$10^{7}${/TEX} CFU/ml and {TEX}$10^{5}{/TEX} CFU/ml in tryptic soy broth supplemented with 0.6% yeast extract, acidified to target pH with citric, fumaric and lactic acids at 37$^{\circ}C$, was completely inactivated after 7 d and 5 d incubation, respectively, except for the acetic acid (9 d). The bactericidal effect decreased at the same pH when the incubation temperature a was reduced from 37$^{\circ}C$ to 4$^{\circ}C$. The pH values of 0.2% acetic (pH 5.1), 0.6% citric (pH 4.2) and 0.4% lactic acid (pH 4.3) in TSBYE were almost correspondent to the minimal inhibitory pH values on E. coli O157:H7 of acetic (pH 4.0), citric (pH 4.0) and lactic acids (pH 4.5).

• Bulletin of the Korean Chemical Society
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• v.14 no.5
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• pp.546-548
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• 1993

The discrete structure of substituted 9-benzonorbornenyl cation 3a and 3c was studied using the empirical ${\Delta}$J equation which was developed by Kelly and coworker$^5$. The ${\Delta}$J values of substituted 9-benzonorbornenyl cations were obtained from p-methyl-6,7-dimethyl benzonorbornen-9-yl (3a) and 9-methyl-6,7-dimethyl benzonorbonen-9-yl (3c) cations under stable ion conditions, and were compared with those of the corresponding ketone analog; these cations were generated by dissolving the corresponding carbinols in superacid at -120$^{\circ}$C and the nmr spectra taken at -60$^{\circ}$C~-90$^{\circ}$C. The ${\Delta}$J values are 8.7 Hz for the bridgehead carbons in cation 3c and 3.1 Hz for cation 3b. The ${\Delta}$J values at C5,8 in fused benzene ring are 14.3 Hz for cation 3c and 8.7 Hz for cation 3a. The excellent correlation of the ${\Delta}$J values with 1$^9F$ chemical shifts of p-fluorophenyl-6,7-dimethylbenzonorbornenyl cation (3d) indicate that ${\Delta}$J value is a reliable probe to charge density at adjacent cationic carbon. These NMR parameters strongly support that the symmetrically ${\pi}$-bridged nonclassical structure (type 2) of substituted 9-benzonorbornenyl cations in stable ion conditions.

• Journal of the Korean Chemical Society
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• v.31 no.3
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• pp.207-214
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• 1987

Rates of solvblysis of benzyl chloride in ethanol-water mixtures have been measured at 30 and $40^{\circ}C$ under various pressures up 1.6 kbar. The plots of 1n k as a function of pressure are fitted to a second order function in p, and values of ${\Delta}V^{\neq}$and ${\Delta}{\beta}^{\neq}$ are obtained from the results. Also the values of various pseudo thermodynamic quantities were evaluated from the rate constants. The relationships of the 1n k to $Q_w$ or 1n $C_w$ indicate that the reaction proceeds through $S_N1$ mechanism. A comparison between the present and the previous results gives that the increasing order of ${\mid}{{\Delta}V_0}^{\neq}{\mid}$ and n-values are $p-Cl>p-H>p-CH_3$ and $p-CH_3>p-H.p-Cl$, respectively. From these results, it is believed substituent such as the $p-CH_3$group favors the $S_N1(1)$ character, while the p-Cl group leads to the $S_N1(2)$ character.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.9
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• pp.1339-1346
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• 2013

This study was carried out to determine the effects of tomato powder (TP) on cooked pork patties during storage at $10{\pm}1^{\circ}C$ in the dark. The total phenolic and flavonoid contents of TP extract were 26.22 mg gallic acid/100 g and 3.52 mg quercetin/100 g, respectively. The extract of TP showed a potential antioxidant activity in the DPPH radical-scavenging assay ($EC_{50}=16.76{\mu}g/mL$). Pork patties were manufactured with 0.25% (T1), 0.5% (T2), 0.75% (T3) and 1.0% (T4) TP in a basic formula (C). The pH and volatile basic nitrogen (VBN) values of T2, T3 and T4 patties were lower (p<0.05) than the C patties during storage. Increased concentration of TP in meat patties decreased (p<0.05) the 2-thiobarbituric acid reactive substances (TBARS) and total plate count (TPC) values at d 7 of storage. Tomato treated-patties had lower (p<0.05) values for lightness ($L^*$), but higher (p<0.05) values for redness ($a^*$) and yellowness ($b^*$) at d 3 and 7 of storage compared with the C. In the case of sensory evaluation, the scores of colour, flavour and overall acceptability of T3 and T4 patties were higher (p<0.05) than those of the C patty after 3 or 7 days of storage.

• Food Science of Animal Resources
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• v.38 no.1
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• pp.1-13
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• 2018

The objective of this study was to investigate quality attributes of beef patties formulated with dried pumpkin pulp and seed mixture (PM). Four different meatball formulations were prepared where lean was replaced with PM as C (0% PM), P2 (2% PM), P3 (3% PM) and P5 (5% PM). Utilization of PM decreased moisture and increased ash content of the patties. Incorporation of 5% PM (P5) increased the pH value of both uncooked and cooked patties compared to C group. Increasing levels of PM increased water-holding capacity. No significant differences were found in cooking yield and diameter change with the addition of PM. Incorporation of PM increased fat and decreased moisture retention of the samples. $a^*$ values were decreased with PM addition, where $L^*$ values did not differ among treatments and $b^*$ values were similar in C, P3 and P5 samples. Textural properties were mostly equivalent to control samples with the incorporation of PM even at higher concentrations. The addition of PM did not significantly affect any of the sensory scores tested. These results indicated that utilization of PM presents the opportunity to decrease the amount of meat besides to improve healthier profile without causing negative changes in physical, chemical and technological quality of beef patties.

• Journal of the Korean Chemical Society
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• v.45 no.1
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• pp.7-13
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• 2001

The interaction of benzenesulfonate anion and its derivatives ($C_6H_5SO_3^-, p-$CH_3C_6H_4SO_3^-, and $p-C_2H_5C_6H_4SO_3^-$) with the micellar system of cationic surfactant TTAB(tetradecyltrimethylammonium bromide) was studied by UV/Vis spectrophotometric method. The solubilization constants($K_s$) of benzenesulfonate anions into the micellar phase of this surfactant have been measured with the change of temperature. The effects of additives(n-pentanol and NaBr) on the solubilization of benzenesulfonate anions by this surfactant system have been also measured. There was a great decrease on the values of $K_s$ and CMC simultaneously with these additives so that the measured values of ln$K_s$ were linear relationships with the values of lnCMC. For the thermodynamic study, various thermodynamic parameters(${\Delta}G^0_s$, ${\Delta}H^0_s$ and ${\Delta}S^0_s$) have been calculated and analyzed from the dependence of Ks values on temperature.