High Performance Liquid Chromatography (HPLC) Detection of Malonaldehydethiobarbituric Acid (MA-TBA) Complex in Ground Pork

Whang, Key The Korean Society of Food Science and Nutrition 1999 Preventive Nutrition and Food Science Vol.4 No.3

For monitoring lipid oxidation development in cooked ground pork during refrigerationm, malonaldehydethiobarbituric acid(MA-TBA) contents were measured using high performance liquid chromatography(HPLC). As the oxidation proceeded during refergeration, TBA-reaction substances(TBARS) absorbances increased and the corresponding HPLC peak areas also increased proportationately. The correlation coefficient between the HPLC peak areas and MA-TBA absorbance were 0.9979. The treatemtn of cetrimide, an ion pairing agent, gave a complete resolution of the MA-TBA complex and the butanol extraction of the complex increased its recovery by 37.8%. Both cetrimide treatment and butanol extraction are essential steps for analyzing MA-TBA complex in ground pork wiht HPLC. A reliable and specific measurement of NA-TBA in ground pork was successfully performed using HPLC.

Detectio of Malonaldehyde-thiobarbituric Acid (MA-TBA) Complex by High Performance Liquid Chromatography(HPLC) in a Model System

Whang, Key The Korean Society of Food Science and Nutrition 1999 Preventive Nutrition and Food Science Vol.4 No.3

Various concentrations of malonaldehyde (MA) produced upon hydrolysis of 1, 1, 3,3-tetraethoxypropane (TEP) were reacted with 2-thiobarbituric acid (TBA)and th e contents of MA-TBA complex were measured both with spectrophotometer and high performance liquid chromatography (HPLC). As the concentrations of MA-TBA increased, their absorbances and the corresponding HPLC peak areas increased. The correlation coefficient between absorbances and HPLC peak areas of MA-TBA peaks from the other compounds and butanol extraction of the complex increased its recovery its recovery by 29.4% . Measurement of the content of MA-TBA complex for monitoring the development of lipid oxidation was proven to be successful with the use of high performance liquid chromatography.

Combination Effect of Modified Atmosphere Packaging and Electron Beam Irradiation on the Oxidative and Microbiological Stability of Ground Pork during Storage

Whang, Key Korean Society for Food Science of Animal Resource 2002 한국축산식품학회지 Vol.22 No.4

분쇄 돈육을 $N_2$와 $CO_2$ 가스로 공기 조절 포장한 후 전자선으로 조사하여(0, 1.5, 3.0 kGy) 돈육을 저장하면서 미생물의 변화와 함께 공기 조절 포장이 전자선 처리에 의한 지방 산화를 억제하는지 관찰하였다. 분쇄 돈육은 공기 조절 포장과 전자선 처리(1.5와 3.0 kGy)후 4$^{\circ}C$에서 6일간 그리고 -15$^{\circ}C$ 에서 3달 동안 저장하면서 주기적으로 미생물 검사와 지방의 산패치를 측정하였다. 일반세균과 중온균의 경우 1.5와 3.0 kGy의 전자선 조사량으로 처리하였을 경우 대조구에 비해 그 증식이 현저히 억제되었음을 관찰하였다. 질소와 이산화탄소를 주입한 포장은 그 자체로도 대조구와 비교하였을 때 저장 중 지방의 산화를 억제하는 데에 큰 효과가 있었으며 또한 공기 조절 포장과 전자선 처리의 병용은 저장 중 분쇄 돈육의 미생물 증식과 지방의 산화를 억제하는데 효과적이었다. Ground pork was packaged(purged) with modified atmosphere (n$_2$ and CO$_2$) and irradiated with the electron beam in order to find out whether modified atmosphere packaging (MAP) inhibit the microbial growth and lipid oxidation development caused by electron beam irradiation. After packaging and irradiation, ground pork was stored at 4$^{\circ}C$ for 6 days and -15$^{\circ}C$ for 3 months, and periodically the microbial counts and the thiobarbituric acid reactive substances (TBARS) for the determination of lipid oxidation were measured. The inhibition of growth of total aerobic bacteria and mesophiles was confirmed when the ground pork was irradiated with the electron beam dose of 1.5 and 3.0 kGy. The N$_2$ or CO$_2$ purging alone was also effective in reducing the development of lipid oxidation of ground pork during storage at 4 and -15$^{\circ}C$. The combination of electron beam irradiation(1.5 and 3.0 kGy) with MAP (N$_2$ or CO$_2$) was effective to inhibit the growth of total aerobic bacteria and mesophiles, and retard the lipid oxidation of ground pork during storage at 4$^{\circ}C$ for 6 days and -15$^{\circ}C$ for 3 months.

Changes of SDS-PAGE Pattern of Pork Myofibrillar Proteins Induced by Electron Beam Irradiation

Whang Key,Jeong, Dong-Kwan,Kim, Hyuk-Il The Korean Society of Food Science and Nutrition 2005 Preventive Nutrition and Food Science Vol.10 No.4

Actin and myosin solutions and fresh ground pork were irradiated with the electron beam (e-beam) at a dose of 0, 1.5, 3.0, 5.0 and 10 kGy. The changes in SDS-PAGE pattern of 2 proteins and the salt-soluble proteins extracted from ground pork after e-beam irradiation were monitored. When the myosin solution was irradiated with e-beam, myosin was degraded completely. Complete myosin degradations were observed even with the lowest dose (1.5 kGy) of e-beam treatment. Actin was degraded with the irradiation, but to a less extent than myosin was. The degradation of actin increased as the e-beam treatment increased from 1.5 to 10.0 kGy. Among the salt-soluble proteins extracted from ground pork, myosin was degraded gradually when the e-beam dose increased from 1.5 up to 10.0 kGy. Similar gradual increase in the degradation of actin also occurred with the increase of irradiation. Increases of 2 low molecular weight compounds (<29 kDa) were observed when the irradiation dose increased from 1.5 to 10.0 kGy. These 2 molecules are thought to be the breakdown products produced from the degradation of major salt-soluble proteins, myosin and actin. The salt-soluble protein content of ground pork did not change with the e-beam irradiation.

Colorimetric Values of Various Myoglobin Derivatives in Pork and Beef Ribeye

Key Whang,Sam Pin Lee,Hyuk Il Kim 한국식품영양과학회 2004 Preventive Nutrition and Food Science Vol.9 No.2

Various myoglobin derivatives were manufactured in pork and beef ribeye in the laboratory and their colorimetric values were measured with a chromameter. The average values of L^* and a^* of pork pigments were higher and b^* values were lower than those of beef pigments. Oxymyoglobin (bright red) is considered to be a desirable fresh red meat pigment for consumer acceptance. The means of L^*, a^* and b^* values of oxymyoglobin were 36.41, 27.32 and 4.71 for pork and 30.54, 25.58 and 9.81 for beef, respectively. Nitrosyl hemochrome, the pigment of processed meat products like sausages and hams had L^*, a^* and b^* values of 47.93, 26.85 and 6.63 for pork and 41.82, 23.19 and 11.82 for beef. It was found that as a discoloration developed in meat and the meat color turned to brown, the L^*, b^* values increased and the a^* value decreased.

Contents of $\beta$-Glucan in Various Cereals and Its Functional Properties

Whang, Key The Korean Society of Food Science and Nutrition 1998 Preventive Nutrition and Food Science Vol.3 No.4

A soluble dietary fiber, $\beta$-glucan, contained in oat and barley has nutritional benefits such as hypocholesterolemic effects and influences blood glucose regulation. The contents of $\beta$-glucan in both cereals range from 3 to 7% with the exception of a certain barley genotype which contains up to 16% $\beta$-glucan. $\beta$-Glucan is distributed mainly in the cell walls of endosperm and the distal (bran) portion of kernel. Various procedures have been developed for increasing the extraction yield of $\beta$-glucan. Oat gum prepared with weak alkali extractionand alcohol proecipitation following protein removal usually contains 80% $\beta$-glucan.The most commonly used method for $\beta$-glucan quantitiation is an enzymatic procedure combining lichenase plus $\beta$-glucosidase followed by measuring the amount of glucos released by glucose oxidase-peroxidase treatment. The increase in foam-and emulsion-stabilizing capacity of $\beta$-glucan is due to the increase in viscosity of the aqueous phase. Therefore, $\beta$-glucan shows great potentials as a thickener and a stabilizer.

Changes of SDS-PAGE Pattern of Pork Myofibrillar Proteins Induced by Electron Beam Irradiation

Key Whang,Dong-Kwan Jeong,Hyuk-Il Kim 한국식품영양과학회 2005 Preventive Nutrition and Food Science Vol.10 No.4

Actin and myosin solutions and fresh ground pork were irradiated with the electron beam (e-beam) at a dose of 0, 1.5, 3.0, 5.0 and 10 kGy. The changes in SDS-PAGE pattern of 2 proteins and the salt-soluble proteins extracted from ground pork after e-beam irradiation were monitored. When the myosin solution was irradiated with e-beam, myosin was degraded completely. Complete myosin degradations were observed even with the lowest dose (1.5 kGy) of e-beam treatment. Actin was degraded with the irradiation, but to a less extent than myosin was. The degradation of actin increased as the e-beam treatment increased from 1.5 to 10.0 kGy. Among the salt-soluble proteins extracted from ground pork, myosin was degraded gradually when the e-beam dose increased from 1.5 up to 10.0 kGy. Similar gradual increase in the degradation of actin also occurred with the increase of irradiation. Increases of 2 low molecular weight compounds (<29 kDa) were observed when the irradiation dose increased from 1.5 to 10.0 kGy. These 2 molecules are thought to be the breakdown products produced from the degradation of major salt-soluble proteins, myosin and actin. The salt-soluble protein content of ground pork did not change with the e-beam irradiation.

HPLC Detection of Free Malonaldehyde for Rapid Measurement of Lipid Oxidation Development

Key Whang,Chang-Min Kim 한국식품영양과학회 2000 Preventive Nutrition and Food Science Vol.5 No.1

Various concentrations of free malonaldehyde were prepared from 1,1,3,3-tetraethoxy propane (TEP). Spectrophotometric determination and HPLC analysis of free malonaldehyde instead of malonaldehyde-thiobarbituric acid (MATBA) complex were conducted. Malonaldehyde was well separated on a μBondapak C_(18) column. The absorbances at 254 ㎚ and the HPLC peak areas of free malonaldehyde increased with the increase in its concentration. The correlation coefficient between absorbances and peak areas was 0.998. The total time elapsed to conduct the whole procedure was less than 15 minutes. This method directly measured the amount of free malonaldehyde in a short period of time successfully. This procedure is expected to be used as a rapid, accurate and specific means to determine the development of lipid oxidation in food.

Contents of β - Glucan in Various Cereals and Its Functional Properties

Key Whang 한국식품영양과학회 1998 Preventive Nutrition and Food Science Vol.3 No.4

A soluble dietary fiber, β-glucan, contained in oat and barley has nutritional benefits such as hypocholesterolemic effects and influences blood glucose regulation. The contents of β-glucan in both cereals range from 3 to 7% with the exception of a certain barley genotype which contains up to 16% β-glucan. β-Glucan is distributed mainly in the cell walls of endosperm and the distal (bran) portion of the kernel. Various procedures have been developed for increasing the extraction yield of β-glucan. Oat gum prepared with weak alkali extraction and alcohol precipitation following protein removal usually contains 80% β-glucan. The most commonly used method for β-glucan quantitation is an enzymatic procedure combining lichenase plus β-glucosidase followed by measuring the amount of glucose released by glucose oxidase-peroxidase treatment. The increase in foam-and emulsion-stabilizing capacity of β-glucan is due to the increase in viscosity of the aqueous phase. Therefore, β-glucan shows great potentials as a thickener and a stabilizer.

High Performance Liquid Chromatography (HPLC) Detection of Malonaldehyde - thiobarbituric Acid (MA - TBA) Complex in Ground Pork

Key Whang 한국식품영양과학회 1999 Preventive Nutrition and Food Science Vol.4 No.3

For monitoring lipid oxidation development in cooked ground pork during refrigeration, malonaldehyde-thiobarbituric acid (MA-TBA) contents were measured using high performance liquid chromatography (HPLC). As the oxidation proceeded during refrigeration, TBA-reactive substances (TBARS) absorbances increased and the corresponding HPLC peak areas also increased proportionately. The correlation coefficient between the HPLC peak areas and MA-TBA absorbances were 0.9979. The treatment of cetrimide, an ion pairing agent, gave a complete resolution of the MA-TBA complex and the butanol extraction of the complex increased its recovery by 37.8%. Both cetrimide treatment and butanol extraction are essential steps for analyzing MA-TBA complex in ground pork with HPLC. A reliable and specific measurement of MA-TBA in ground pork was successfully performed using HPLC.