Separation of Phosvitin from Egg Yolk without Using Organic Solvents

The objective of this study was to develop a new method to separate phosvitin from egg yolk without using organic solvents. Phosvitin was extracted from yolk granules using 10% NaCl or 10% (NH4)2SO4 (final concentration) and then treated with heat to precipitate the lipoproteins from the extracted solution. The optimal pH for the phosvitin extraction from yolk granules was determined, and the iron-binding ability of the extracted phosvitin (final product) was tested. Adding 10% (NH4)2SO4 disrupted the granules, and the subsequent thermal treatment at 90°C for 1 h precipitated low density and high density lipoproteins, which enabled separation of phosvitin by centrifugation. The phosvitin concentration in the extract was significantly higher when the pH of the solution was adjusted to pH ≥9. The purity and recovery rate of phosvitin at the end of the separation process were approximately 78% and 56%, respectively. The separated phosvitin was confirmed to have ferrous and ferric iron binding ability. The advantages of this new method compared with the traditional methods include no organic solvents and high-priced equipment are needed for the separation. Also, this method is more environment and consumer friendly than that of the traditional methods

Comparison of Quality Traits of Meat from Korean Native Chickens and Broilers Used in Two Different Traditional Korean Cuisines

With the aim of investigating the differences in the quality traits between Korean native chicken (Hanhyup, KNC) and broilers commonly used in two different traditional Korean cuisines, the chemical composition and sensory properties of breast and thigh meat from the two chicken strains were assessed. KNC for baeksuk (chicken meat braised in soup with various Oriental medicinal plants; KNL), KNC for samgyetang (similar to baeksuk but young chickens and ginseng are used; KNS), broiler for baeksuk (BL), and broiler for samgyetang (BS) were used as treatments in this study. KNL and KNS contained higher protein but lower fat content than BL and BS. The L* values of breast and thigh meat, but not the a* values, were significantly different between KNS and BS, whereas significant differences in both values were observed between KNL and BL. Compared to the other three types of chickens, KNS contained the highest total and insoluble collagen content, and KNL and BL showed higher inosine-5’-monophosphate content in their meat. Overall, KNL and KNS contributed darker, less tender meat with higher protein and less fat content together with more n-3 fatty acids, as opposed to their counterparts used for the same cuisines. Based on the results of the sensory analysis, even though there are some differences in physiochemical traits, different chicken sources do not differ in overall sensory quality. This information can help consumers to understand better the meat available for their preferred traditional cuisines

Effect of atmospheric pressure plasma on inactivation of pathogens inoculated onto bacon using two different gas compositions. Food Microbiol

a b s t r a c t Atmospheric pressure plasma (APP) is an emerging non-thermal pasteurization method for the enhancement of food safety. In this study, the effect of APP on the inactivation of pathogens inoculated onto bacon was observed. Sliced bacon was inoculated with Listeria monocytogenes (KCTC 3596), Escherichia coli (KCTC 1682), and Salmonella Typhimurium (KCTC 1925). The samples were treated with APP at 75, 100, and 125 W of input power for 60 and 90 s. Two gases, helium (10 lpm) or a mixture of helium and oxygen, (10 lpm and 10 sccm, respectively) were used for the plasma generation. Plasma with helium could only reduce the number of inoculated pathogens by about 1e2 Log cycles. On the other hand, the helium/oxygen gas mixture was able to achieve microbial reduction of about 2e3 Log cycles. The number of total aerobic bacteria showed 1.89 and 4.58 decimal reductions after plasma treatment with helium and the helium/oxygen mixture, respectively. Microscopic observation of the bacon after plasma treatment did not find any significant changes, except that the L * -value of the bacon surface was increased. These results clearly indicate that APP treatment is effective for the inactivation of the three pathogens used in this study, although further investigation is needed for elucidating quality changes after treatment

Effect of atmospheric pressure plasma on inactivation of pathogens inoculated onto bacon using two different gas compositions

Atmospheric pressure plasma (APP) is an emerging non-thermal pasteurization method for the enhancement of food safety. In this study, the effect of APP on the inactivation of pathogens inoculated onto bacon was observed. Sliced bacon was inoculated with Listeria monocytogenes (KCTC 3596), Escherichia coli (KCTC 1682), and Salmonella Typhimurium (KCTC 1925). The samples were treated with APP at 75, 100, and 125W of input power for 60 and 90s. Two gases, helium (10 lpm) or a mixture of helium and oxygen, (10 lpm and 10 sccm, respectively) were used for the plasma generation. Plasma with helium could only reduce the number of inoculated pathogens by about 1-2 Log cycles. On the other hand, the helium/oxygen gas mixture was able to achieve microbial reduction of about 2-3 Log cycles. The number of total aerobic bacteria showed 1.89 and 4.58 decimal reductions after plasma treatment with helium and the helium/oxygen mixture, respectively. Microscopic observation of the bacon after plasma treatment did not find any significant changes, except that the L*-value of the bacon surface was increased. These results clearly indicate that APP treatment is effective for the inactivation of the three pathogens used in this study, although further investigation is needed for elucidating quality changes after treatment. (C) 2010 Elsevier Ltd. All rights reserved.N

Effects of high hydrostatic pressure on the quality and safety of beef after the addition of conjugated linoleic acid

We evaluated the effect of high pressure (HP) for infusing of conjugated linoleic acid (CLA) on the quality and storage stability of beef loin. To beef loins in a bag before sealing, CLA alone (1%; CLA), CLA + 0.15% lecithin (CL), or CL + 0.001% alpha-tocopherol (CLT) were poured into the bag, vacuum-packed, and HP-treated with 0.1,300,450, and 600 MPa for 5 min. CLA level, cooking loss, and pH were significantly increased, when pressure increased from 0.1 to 600 MPa. Increases in pressure levels and storage periods increased TBARS about 1.04 and 3.85 fold values. Total aerobic bacteria were not detected in HP treated samples (450 and 600 MPa). CL or CLT with HP (300MPa) caused higher overall acceptance and willingness to buy. Hence, the addition of CLA with HP (300 MPa) can improve the nutritional and microbiological quality of beef loin with acceptable sensory quality. Industrial relevance: High pressure (HP) processing is a safe and consumer-friendly preservation technology that can eliminate pathogenic and spoilage microorganisms and extends product shelf-life without detrimental effects of thermal processing or use of preservatives or additives. However, meat with lower intramuscular fat content can be rejected by some consumers due to the lack of suitable sensorial qualities. On the other hand, meat with higher intramuscular fat content, beef in particular, may also cause consumers' concern because of the elevated level of saturated fatty acids. This particular study demonstrated that HP in combination with the infusion of CLA can be used for the enhancement of nutritional and microbiological quality of beef. Based on the results, it can be suggested that not only the infusion of CLA but also other oils originated from plants in combination with HP treatment can modify fatty acid composition. (C) 2014 Elsevier Ltd. All rights reserved.N

Elucidation of Antioxidant Activity of Phosvitin Extracted from Egg Yolk using Ground Meat

Phosvitin was extracted from a chicken egg yolk and the iron-binding, along with antioxidative activity of the extracted phosvitin, was determined after mixing with ground beef at the concentrations of 100 and 500 mg/kg of meat. The electrophoretic pattern of the extracted phosvitin on SDS-PAGE was found to be identical to that of the standard phosvitin. The extracted phosvitin at 1,000 mu g/mL showed an ability to bind approximately 65% of the iron in a 3 mM iron solution. Lipid oxidation was inhibited in the ground beef mixed with 500 mg/kg of the extracted phosvitin, during storage at 4 degrees C compared to that of the control (p<0.05). Additionally, color stability of ground beef containing the extracted phosvitin was enhanced (p<0.05). The pH, cooking loss, texture, and sensory properties of the ground beef were not affected, by adding up to 500 mg/kg of the extracted phosvitin. This result suggests that the phosvitin extracted from egg yolk could be used as an antioxidant reagent. In particular, phosvitin would be more amenable for use in meat products because it is a natural protein derived from animal products.Y

Effects of Electron Beam Irradiation on Pathogen Inactivation, Quality, and Functional Properties of Shell Egg during Ambient Storage

This study investigated the effects of electron beam irradiation on pathogens, quality, and functional properties of shell eggs during storage. A 1st grade 1-d-old egg was subjected to electron beam irradiation at 0, 1, 2, and 3 kGy, after which the number of total aerobic bacteria, reduction of inoculated Escherichia coli and Salmonella Typhimurium, egg quality, and functional properties were measured. Electron beam irradiation at 2 kGy reduced the number of E. coli and S. Typhimurium cells to a level below the detection limit (<10(2) CFU/g) after 7 and 14 d of storage. Egg freshness as measured by albumen height and the number of Haugh units was significantly reduced by 1-kGy irradiation. The viscosity of irradiated egg white was also significantly decreased by increased irradiation, whereas its foaming ability was increased. Electron beam irradiation also increased lipid oxidation in egg yolks. These results suggest that electron beam irradiation reduces the freshness of shell eggs while increasing the oxidation of egg yolk and improving important functional properties such as foaming capacity. Electron beam irradiation can also be applied to the egg breaking process since the irradiation reduces the viscosity of egg white, which can allow egg whites and yolks to be separated with greater efficiency.Y

Investigation of SNPs in FABP3 and FABP4 Genes and Their Possible Relationships with Fatty Acid Composition in Broiler

There is limited information of the genetic effect for fatty acid composition in chicken meat. This study assessed the association of FABP3 and FABP4 genes affecting fatty acid composition in broilers. Two single nucleotide polymorphisms (SNPs) were detected in FABP3 gene and five SNPs were identified in FABP4 gene. The SNPs located in intron 1 and exon 1 of FABP3 and FABP4, respectively, were used for genotyping using PCR-RFLP method. The SNPg.285C>T in FABP4 showed suggestive association with high arachidonic acid (C20:4) in CT genotypes (P=0.068). However, the SNP g.508C>T in FABP3 showed no significant associations with fatty acid composition. These results are the first report to investigate the SNPs in FABP3 and FABP4 genes and their associations with fatty acid composition, although we only found the possible association of FABP4 SNP with fatty acid composition. These results should provide valuable information for further investigation of the genes affecting fatty acid composition in chicken.N

Instrumental Methods for Differentiation of Frozen-thawed from Fresh Broiler Breast Fillets

To differentiate between frozen-thawed and fresh broiler breast fillets, different methods such as optical microscopy and measurement of drip loss, pH, torrymeter and K-value were performed. A total of 10 samples of fresh and frozen-thawed breast fillets were stored in a refrigerator (4 degrees C) for 5 d. Optical microscopy of the frozen-thawed breast fillets found structural changes caused by ice crystals, which may have significantly increased drip loss compared to fresh breast fillet. The pH and K-value could not be distinguished between the two breast fillets during storage. However, the torrymeter values of the fresh and frozen-thawed breast fillets were significantly different (p<0.05). The results indicate that both optical microscopy and torrymeter measurement can be effective methods for differentiating between fresh and frozen-thawed breast fillets. However, optical microscopy may be difficult to implement in the marketplace since it requires much time and effort. Thus, the determination of the torrymeter value is the easiest and most rapid instrumental method among those tested for the differentiation of frozen-thawed chicken breast fillet from fresh one.Y