Heat-induced and other chemical changes in commercial UHT milks

2005 ◽  
Vol 72 (4) ◽  
pp. 442-446 ◽  
Author(s):  
Anthony J Elliott ◽  
Nivedita Datta ◽  
Boka Amenu ◽  
Hilton C Deeth
Keyword(s):  
Heat Treatment ◽  
Bovine Serum Albumin ◽  
Bovine Serum ◽  
Room Temperature ◽  
Whey Proteins ◽  
Thermally Induced ◽  
Heated Milk ◽  
Heat Treated ◽  
Induced Changes ◽  
Β Lactoglobulin

The properties of commercial directly and indirectly heated UHT milks, both after heating and during storage at room temperature for 24 weeks, were studied. Thermally induced changes were examined by changes in lactulose, furosine and acid-soluble whey proteins. The results confirmed previous reports that directly heated UHT milks suffer less heat damage than indirectly heated milk. During storage, furosine increased and bovine serum albumin in directly heat-treated milks decreased significantly. The changes in lactulose, α-lactalbumin and β-lactoglobulin were not statistically significant. The data suggest that heat treatment indicators should be measured as soon as possible after processing to avoid any misinterpretations of the intensity of the heat treatment.

Correlations between the content of selected whey proteins in cow milk

2017 ◽  
Vol 13 (1) ◽  
pp. 33-45
Author(s):  
Aneta Brodziak ◽  
Jolanta Król ◽  
Anna Litwińczuk ◽  
Anna Wolanciuk
Keyword(s):  
Bovine Serum Albumin ◽  
Serum Albumin ◽  
Bovine Serum ◽  
Whey Proteins ◽  
Correlation Coefficients ◽  
Hplc Method ◽  
Cow Milk ◽  
Black And White ◽  
Scatter Plots ◽  
Β Lactoglobulin

The aim of the study was to determine the correlations between the concentrations of major whey proteins in cow milk. A total of 2,278 milk samples from Polish Holstein-Friesian (Black-and-White and Red-and-White varieties), Simmental and Jersey cows were analysed. In each sample the content of major whey proteins, i.e. α-lactalbumin, β-lactoglobulin, bovine serum albumin, lactoferrin and lysozyme were determined by the RP-HPLC method. Matrix scatter plots were prepared to determine the correlations between the concentrations of individual whey proteins. In the vast majority of cases a significant relationship was found between the content of individual whey proteins. Taking into account the production season and breed of cow, highly significant (p=0.001) negative correlation coefficients were obtained for the content of α-lactalbumin and bovine serum albumin, for α-lactalbumin and lysozyme, for β-lactoglobulin and bovine serum albumin, and for β-lactoglobulin and lysozyme. Positive correlations were observed for the concentrations of α-lactalbumin with β-lactoglobulin, lactoferrin and lysozyme, as well as for bovine serum albumin with lysozyme.

Facilitation of Cleaning of Alumina Surfaces Fouled with Heat-Treated Bovine Serum Albumin by Ozone Treatment

2001 ◽  
Vol 64 (1) ◽  
pp. 108-112 ◽  
Author(s):  
HIROMI URANO ◽  
SATOSHI FUKUZAKI
Keyword(s):  
Bovine Serum Albumin ◽  
Serum Albumin ◽  
Bovine Serum ◽  
Room Temperature ◽  
Treatment Time ◽  
Ozone Treatment ◽  
Gaseous Ozone ◽  
Heat Treated ◽  
Ozone Pretreatment ◽  
Increasing Temperature

Facilitation of cleaning of alumina (Al2O3) particles fouled with heat-treated bovine serum albumin (BSA), which contains sulfhydryl groups on the molecule, by gaseous ozone was studied. With increasing temperature of heat treatment, the amount of adsorbed BSA onto Al2O3 surfaces increased, whereas the rate of BSA desorption during alkali cleaning decreased markedly, resulting in the larger amounts of BSA remaining on Al2O3 surfaces. No significant amounts of BSA were removed from Al2O3 surfaces by alkali cleaning alone when treated at temperatures above 120°C. Before alkali cleaning, the heat-treated, BSA-fouled Al2O3 at 150°C were treated with 0.05 to 0.30% (vol/vol) gaseous ozone at room temperature. Ozone pretreatment markedly accelerated the rate of BSA desorption during subsequent alkali cleaning. The effect of ozone pretreatment on BSA removal depended on the concentration of ozone and treatment time and hence on the total amount of ozone supplied. The molecular weight (MW) of desorbed BSA during alkali cleaning without ozone pretreatment coincided with the MW of the native BSA, whereas the MW of desorbed BSA during the combined ozone-alkali cleaning was lower than the MW of the native BSA. This indicated that the heat-treated BSA molecules adsorbed on Al2O3 were partially decomposed into some fragments by ozone pretreatment, resulting in the facilitation of the removal of BSA during alkali cleaning.

Effect of Heat Treatment on the Microstructure and Property of TiAl Alloys Prepared by Gas Atomization Powders

2013 ◽  
Vol 747-748 ◽  
pp. 497-501
Author(s):  
Na Liu ◽  
Zhou Li ◽  
Guo Qing Zhang ◽  
Hua Yuan ◽  
Wen Yong Xu ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Heat Treatment Temperature ◽  
Tial Alloy ◽  
Lamellar Microstructure ◽  
Treatment Temperature ◽  
Gas Atomization ◽  
Thermally Induced ◽  
Heat Treated ◽  
Fine Duplex ◽  
Step Heat Treatment

Powder metallurgical TiAl alloy was fabricated by gas atomization powders, and the effect of heat treatment temperature on the microstructure evolution and room tensile properties of PM TiAl alloy was investigated. The uniform fine duplex microstructure was formed in PM TiAl based alloy after being heat treated at 1250/2h followed by furnace cooling (FC)+ 900/6h (FC). When the first step heat treatment temperature was improved to 1360/1h, the near lamellar microstructure was achieved. The ductility of the alloy after heat treatment improved markedly to 1.2% and 0.6%, but the tensile strength decreased to 570MPa and 600MPa compared to 655MPa of as-HIP TiAl alloy. Post heat treatment at the higher temperature in the alpha plus gamma field would regenerate thermally induced porosity (TIP).

scholarly journals Heat treatment induces an increase in intracellular cyclic AMP content in human epidermoid A-431 cells

1991 ◽  
Vol 276 (3) ◽  
pp. 683-689 ◽  
Author(s):  
J G Kiang ◽  
Y Y Wu ◽  
M C Lin
Keyword(s):  
Heat Treatment ◽  
Cyclic Amp ◽  
Adenylate Cyclase ◽  
G Proteins ◽  
Phosphodiesterase Inhibitors ◽  
Metabolic Inhibitors ◽  
Thermally Induced ◽  
Heat Treated ◽  
Atp Breakdown ◽  
In Cells

The basal level of intracellular cyclic AMP (cAMPi) in A-431 cells incubated at 37 degrees C in Na(+)-containing Hanks solution is 2086 +/- 139 fmol/10(6) cells. When cells are exposed to 45 degrees C for 10 min, cAMPi increases by 40 +/- 4%, and then returns to basal levels within 30 min. Incubating cells in Ca(2+)-free or Mg(2+)-free Hanks solution has no effect on the heat-induced increase in cAMPi, but the increase is inhibited by acid-loading cells to intracellular pH 7.0 or 6.8. In unheated cells, cAMPi increases by 16 +/- 8%, 53 +/- 7%, or 39 +/- 8%, when incubated with isobutyl-1-methylxanthine (1 mM), Ro 20-1724 (0.5 mM), or theophylline (1 mM) respectively. However, heat treatment further elevates cAMPi in cells treated with phosphodiesterase inhibitors, indicating that heat treatment and phosphodiesterase inhibitors elevate cAMPi by a different pathway(s). Heat treatment increases adenylate cyclase activity 2.5-fold. When forskolin (150 microM), an adenylate cyclase stimulator, is applied to cells, the basal cAMPi increases 28 +/- 6-fold compared with controls. Subsequent heating of these cells lowers cAMPi levels to 7.0 +/- 0.5 times that in control cells. This decrease is prevented by pretreatment with pertussis toxin (30 ng/ml, 24 h), suggesting that G-proteins are involved in the process of heat-induced cAMPi increase. 2-Deoxy-D-glucose (10 mM), NaN3 (10 mM) and 2,4-dinitrophenol (1 mM) also increase cAMPi in A-431 cells. However, application of these metabolic inhibitors to cells before heat treatment does not result in cAMPi levels greater than that observed in cells with heat alone. Similar observations are obtained in heat-treated cells previously exposed to adenosine, but not to AMP or ADP. These data are the first to suggest that thermally induced increase in cAMPi is due to a combination of activation of adenylate cyclase and G-proteins, and an increase in adenosine owing to ATP breakdown caused by hyperthermia.

Attachment of Listeria innocua to Polystyrene: Effects of Ionic Strength and Conditioning Films from Culture Media and Milk Proteins

2014 ◽  
Vol 77 (3) ◽  
pp. 427-434 ◽  
Author(s):  
GILLES ROBITAILLE ◽  
SÉBASTIEN CHOINIÈRE ◽  
TIMOTHY ELLS ◽  
LOUISE DESCHÈNES ◽  
AKIER ASSANTA MAFU
Keyword(s):  
Bovine Serum Albumin ◽  
Serum Albumin ◽  
Bacterial Adhesion ◽  
Bovine Serum ◽  
Biofilm Formation ◽  
Milk Protein ◽  
Milk Proteins ◽  
Listeria Innocua ◽  
Conditioning Films ◽  
Β Lactoglobulin

It is recognized that bacterial adhesion usually occurs on conditioning films made of organic macromolecules absorbed to abiotic surfaces. The objectives of this study were to determine the extent to which milk protein–coated polystyrene (PS) pegs interfere with biofilm formation and the synergistic effect of this conditioning and hypertonic growth media on the bacterial adhesion and biofilm formation of Listeria innocua, used as a nonpathogenic surrogate for Listeria monocytogenes. PS pegs were uncoated (bare PS) or individually coated with whey proteins isolate (WPI), β-lactoglobulin, bovine serum albumin, or tryptic soy broth (TSB) and were incubated in bacterial suspensions in modified Welshimer's broth. After 4 h, the number of adherent cells was dependent on the coating, as follows: TSB (107 CFU/ml) > bare PS > β-lactoglobulin > bovine serum albumin ≈ WPI (104 CFU/ml). The sessile cell counts increased up to 24 h, reaching >107 CFU per peg for all surfaces (P > 0.1), except for WPI-coated PS; this indicates that the inhibitory effects of milk protein conditioning films are transient, slowing down the adhesion process. The 4-h bacterial adhesion on milk protein–coated PS in modified Welshimer's broth supplemented with salt (0 to 10% [wt/vol]) did not vary (P > 0.1), indicating that conditioning with milk proteins was the major determinant for inhibition of bacterial adhesion and that the synergetic effect of salt and milk proteins on adhesion was minimal. Moreover, the presence of 5 to 10% salt significantly inhibited 24-h biofilm formation on the TSB-coated and bare PS, with a decrease of >3 log at 10% (wt/vol) NaCl and almost completely depleted viable sessile bacteria on the milk protein–coated PS.

Self-healing of thermally-induced, biocompatible and biodegradable protein hydrogel

RSC Advances ◽  
2016 ◽  
Vol 6 (61) ◽  
pp. 56183-56192 ◽  
Author(s):  
Jun Chen ◽  
Xiaoyu Ma ◽  
Qiuchen Dong ◽  
Donghui Song ◽  
Derek Hargrove ◽  
...  
Keyword(s):  
Bovine Serum Albumin ◽  
Serum Albumin ◽  
Bovine Serum ◽  
Self Healing ◽  
Thermally Induced ◽  
External Heating ◽  
Good Biocompatibility ◽  
Recovery Performance

Almost 100% self-healing extent recovery performance was observed in thermal-induced bovine serum albumin hydrogel with external heating. Good biocompatibility and biodegradability of this materials were also demonstrated.

CHANGES IN MILK, WHEY, AND BLUE CHEESE AS INDUCED BY BENZOYL PEROXIDE1,2

1974 ◽  
Vol 37 (5) ◽  
pp. 244-249 ◽  
Author(s):  
C. J. Washam ◽  
G. W. Reinbold ◽  
E. R. Vedamuthu ◽  
R. Jorgensen
Keyword(s):  
Heat Treatment ◽  
Benzoyl Peroxide ◽  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Whey Proteins ◽  
Milk Proteins ◽  
Bleaching Process ◽  
Blue Cheese ◽  
Milk Whey ◽  
Heat Treated

Milk proteins were subjected to treatment with various levels of benzoyl peroxide, with and without heating at 60 C for 2 h. Heating had a pronounced effect on whey proteins, but polyacrylamide gel electrophoresis revealed changes in proteins not attributable to heat alone. The effect on proteins was reflected in an increased tendency for the benzoyl peroxide-heat treated cheeses to expel moisture during leakage tests. Use of 17.8 ppm benzoyl peroxide resulted in a markedly whiter cheese than that made using 5.9 ppm and reflectance studies indicated this to be true even when no heat treatment accompanied the benzoyl peroxide. Use of benzoyl peroxide in the bleaching process did not decrease mold development in ripening loaves nor was acid production by lactic cultures diminished. In addition, proteolysis of milk proteins by rennet was not reduced by the presence of benzoyl peroxide.

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