scholarly journals Heat treatment of liquid egg yolk

2020 ◽  
Author(s):  
Emna Ayari ◽  
Csaba Németh ◽  
Karina Ilona Hidas ◽  
Adrienn Tóth ◽  
Dávid Láng ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Differential Scanning Calorimetry ◽  
Apparent Viscosity ◽  
Processing Time ◽  
Egg Yolk ◽  
Endothermic Peak ◽  
Scanning Calorimetry ◽  
New Methods ◽  
Egg Products

AbstractStarting from mechanical revolution, each day new methods and new equipment have emerged. Today, the Ultra Heat Treatment (UHT) is one of the important technologies that permits to the industry to reduce processing time while maintaining the same quality of the products. Egg and egg products are known as heat-sensitive products, so the UHT enables us to preserve their qualities after a heat treatment.Our aim is to study the effect of UHT treatment (approximately 67 °C for 190 s) on the Liquid Egg Yolk (LEY). For twenty-one days, the color and the apparent viscosity were measured every seven days, we also studied the damage of protein using DSC (Differential Scanning Calorimetry).Comparing the two graphs of DSC, the denaturation of protein is distinct. The endothermic peak decreased. This could be seen also on the rheological curves. The apparent viscosity is diminished from 231 mPa.s on the 1st day of storage to 224 mPa.s on 21st day. However, the treated LEY could be stored for longer period than the raw LEY.

scholarly journals HOW DOES CRYOGENIC FREEZING AFFECT THE CALORIMETRIC PROPERTIES OF LIQUID EGG PRODUCTS?

2019 ◽  
Vol 11 (1) ◽  
Author(s):  
Hidas Karina Ilona ◽  
Ildikó Csilla Nyulas-Zeke ◽  
László Friedrich ◽  
Anna Visy ◽  
Judit Csonka ◽  
...  
Keyword(s):  
Liquid Nitrogen ◽  
Frozen Storage ◽  
Colour Change ◽  
Egg Yolk ◽  
Egg White ◽  
Dry Matter Content ◽  
Scanning Calorimetry ◽  
Egg Products ◽  
Liquid Whole Egg ◽  
Whole Egg

Eggs are widely utilized because of their high nutrient value, coagulating, foaming, emulsifying and sometimes even colouring or flavouring facilities in food manufacturing. Production of processed egg products shows an increasing trend. Frozen products belong to first processing, their shelf life can increase up to 1 year. By freezing, a large reduction in microbial loss can be achieved. But different undesirable processes can occur. The effect of freezing on animal cells is highly dependent on freezing parameters. It has a different effect on egg subtituents. Egg yolk undergoes a gelation process while proteins can denaturate. In our study pasteurized liquid egg products (liquid egg white, liquid egg yolk and liquid whole egg) were frozen by dripping into liquid nitrogen. After that, a 14-day frozen storage experiment was carried out at -18°C. Before freezing and on the 1th, 7th and 14th days of storage experiment pH, dry matter content, colour and calorimetric properties (denaturation temperatures and enthalpy of denaturation) with differential scanning calorimetry were tested. For statistical analysis, one-way ANOVA (α = 0.05) was employed. In our experiment, we found no significant change in calorimetric properties of liquid egg white after freezing, but significant decreasing of enthalpy and denaturation temperatures of liquid egg yolk and liquid whole egg was identified. In contrast, frozen storage had a decreasing effect in all these products. Freezing caused a clearly visible colour change in LEW, a visible change in colour of LWE and a very clearly visible change in colour of LEY. In case of LEW and LEY changes increased to clearly visible 14 days. In conclusion, our results show that frozen storage had a greater effect on liquid egg products properties than freezing in liquid nitrogen.

Structures and properties of mixtures of branched chain compounds and lecithin: phytol, α-tocopherol (vitamin E), and phytanic acid

1979 ◽  
Vol 57 (4) ◽  
pp. 458-465 ◽  
Author(s):  
Robert J. Cushley ◽  
Bruce J. Forrest ◽  
Anne Gillis ◽  
Jenifer Tribe
Keyword(s):  
Differential Scanning Calorimetry ◽  
Vitamin E ◽  
Phytanic Acid ◽  
Liquid Crystalline ◽  
Egg Yolk ◽  
Scanning Calorimetry ◽  
Chain Molecules ◽  
Structures And Properties ◽  
Branched Chain ◽  
Crystalline Phase Transition

Phospholipid bilayers containing branched chain molecules, phytol (1), vitamin E (2), and phytanic acid (3), have been investigated by 31P nmr, esr, and differential scanning calorimetry (dsc).A 31P lanthanide induced shift study indicated varying permeabilities to Pr3+ in the order phytanic acid > vitamin E > phytol > egg yolk lecithin alone; the half-lives (in days) were 0.002, 0.14, 0.83, and 6.5, respectively. The activation energy for Pr3+ permeation through the egg yolk lecithin–phytol membrane was found to be 84.9 ± 0.8 kJ.The following esr order parameters, S3, were obtained using the extrinsic spin label, 5-doxylpalmitic acid, in oriented mixed multibilayers: S3 (1) = 0.29, S3 (2) = 0.50, and S3 (3) = 0.02.Differential scanning calorimetry revealed a lowering of the gel–liquid crystalline phase transition temperature, Tc, as the concentration of incorporated isoprenoid compound increases, with eventual disappearance of the endotherm. Specific entropy, s, calculated for dipalmitoyl lecithin +25 mol% 3 is 126 J kg−1 K−1 compared to s = 114.2 J kg−1 K−1 for 1and s = 85 J kg−1 K−1 for 2.

Influence of Tapioca Starch on Thermal Properties of Wheat Flour-Based Batter and Quality of Fried Battered Chicken Wingsticks

2015 ◽  
Vol 11 (5) ◽  
pp. 641-650 ◽  
Author(s):  
Soraya Ketjarut ◽  
Rungnaphar Pongsawatmanit
Keyword(s):  
Differential Scanning Calorimetry ◽  
Thermal Properties ◽  
Wheat Flour ◽  
Oil Content ◽  
Peak Time ◽  
Oil Uptake ◽  
Scanning Calorimetry ◽  
Tapioca Starch ◽  
Flour Blend

Abstract The effect of tapioca starch (TS) on the pasting and thermal properties of wheat flour (WF)-based batter and on the quality of fried, battered chicken wingsticks was investigated. A dry mix (91.4% WF/TS flour blend (100/0, 75/25 and 50/50), 3.1% leavening agent and 5.5% salt) was mixed with water (1:1.3) for batter preparation. The peak viscosity of the diluted batters increased with increasing TS replacement whereas the peak time and viscosity after holding at 95°C for 4 min decreased. Substitution of TS in the WF-based batter decreased pickup but increased the onset and conclusion temperatures from differential scanning calorimetry. A lower oil content was observed in the pre-fried crusts containing TS which was expected from the gelatinization behaviour of the batters. The TS substitution enhanced both the lightness and crispness of the final fried crust and the liking scores of the fried, battered chicken wingsticks. The results suggest that TS substitution modified the gelatinization behaviour of the WF-based batters affecting the oil uptake and quality in the fried battered products.

Quality of Brazilian vegetable oils evaluated by (modulated) differential scanning calorimetry

2011 ◽  
Vol 110 (3) ◽  
pp. 1353-1365 ◽  
Author(s):  
Pieter Samyn ◽  
Gustaaf Schoukens ◽  
Leo Vonck ◽  
Dirk Stanssens ◽  
Henk Van den Abbeele
Keyword(s):  
Differential Scanning Calorimetry ◽  
Vegetable Oils ◽  
Scanning Calorimetry ◽  
Modulated Differential Scanning Calorimetry

In vivo characterization of thermal stabilities of Aeropyrum pernix cellular components by differential scanning calorimetry

2007 ◽  
Vol 53 (9) ◽  
pp. 1038-1045 ◽  
Author(s):  
Igor Milek ◽  
Miha Črnigoj ◽  
Nataša Poklar Ulrih ◽  
Gönül Kaletunç
Keyword(s):  
Heat Treatment ◽  
Differential Scanning Calorimetry ◽  
Optical Data ◽  
Lag Phase ◽  
Scanning Calorimetry ◽  
Thermal Stabilities ◽  
Whole Cell ◽  
Whole Cells ◽  
Aeropyrum Pernix ◽  
Cellular Components

Revival studies of Aeropyrum pernix show that the viability of cells and cell recovery after heat treatment depends on the temperature of treatment. Differential scanning calorimetry (DSC) is used to analyze the relative thermal stabilities of cellular components of A. pernix and to identify the cellular components responsible for the observed lag phase and reduced maximum growth following a heat treatment. DSC thermograms show 5 visible endothermic transitions with 2 major transitions. DSC analysis of isolated crude ribosomes aids the assignment of the 2 major peaks observed in whole-cell thermograms to denaturation of ribosomal structures. A comparison of partial and immediate full rescan thermograms of A. pernix whole cells indicates that both major peaks represent irreversible thermal transitions. A DNA peak is also identified in the whole-cell thermogram by comparison with the optical data of isolated pure DNA. DNA melting is shown to be irreversible in dilute solution, whereas it is partially reversible in whole cells, owing at least in part, to restricted volume effects. In contrast to mesophilic organisms, hyperthermophilic A. pernix ribosomes are more thermally stable than DNA, but in both organisms, irreversible changes leading to cell death occur owing to ribosomal denaturation.

Synthesis of nanocomposite coating of electrodeposed amorphic layers of the Ni–P–W system

2020 ◽  
pp. 53-60
Author(s):  
A. V. Krasikov
Keyword(s):  
Electron Microscopy ◽  
Heat Treatment ◽  
Differential Scanning Calorimetry ◽  
Phase Composition ◽  
Diffraction Analysis ◽  
Nanocomposite Coating ◽  
Nanocrystalline Phase ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray

The processes of the formation of the nanocomposite coating of Ni–11.5% P–5%W were studied during the heat treatment of amorphous electrodeposited layers. Using the method of differential scanning calorimetry, the temperature of the onset of crystallization of the nanocrystalline phase Ni3P was determined. X-ray diffraction analysis showed that heat treatment produces Ni3P phosphides and, presumably, Ni5P2, the size of which, according to electron microscopy, is 5–50 nm. The influence of the duration of heat treatment on the phase composition and microhardness of coatings is investigated.

Effects of HHP’s Holding Time on Proteins of Liquid Egg Products

2021 ◽  
pp. 17-20
Author(s):  
Adrienn Tóth ◽  
◽  
Csaba Németh ◽  
Karina Hidas ◽  
Annamária Barkó ◽  
...  
Keyword(s):  
Functional Properties ◽  
Protein Structures ◽  
Applied Pressure ◽  
Egg Yolk ◽  
Food Preservation ◽  
Holding Time ◽  
Scanning Calorimetry ◽  
Minimal Processing ◽  
Processing Technologies ◽  
Egg Products

Today’s consumers require food products with fresh, or fresh-like characteristics. Minimal processing technologies are indicated as technologies with a gentle impact on sensorial and techno-functional properties. High Hydrostatic Pressure (HHP) is a widely used minimal technology considered as a cold pasteurization method in food preservation. The effect of applied pressure of HHP is well understood, but the holding time of HHP treatment is not extensively investigated in topic of proteins. One of the most important attribute of liquid egg products are the great foaming ability, foaming stability as well as emulsifying properties. These techno-functional properties are highly influenced by the protein structures of egg products. In our study, liquid egg products were pressurized at 400 MPa, for 1, 3, 5 7 and 10 minutes. The protein structures of liquid egg white (LEW), liquid egg yolk (LEY) and liquid whole egg (LWE) were investigated using Differential Scanning Calorimetry (DSC).Our study pointed out that after HHP treatment at 400 MPa, for 10 minutes 12% decrease in denaturation enthalpy of LWE was observed. In LEY 30% decrease was detected after 10 minutes HHP treatment. The highest impact of HHP treatment (35% decrease in denaturation enthalpy) in LWE was noted. The changes in protein structures of liquid egg products were smaller, than the effects of higher pressure applied for preservation. In aspects of techno-functional properties applying a longer holding time is more favourable, than applying a higher pressure.

Determining the quality of diterpene glycosides, obtained from stevia leaves

2016 ◽  
Vol 3 (2) ◽  
pp. 19-25
Author(s):  
M. Royik ◽  
I. Kuznetsova ◽  
V. Holodniak ◽  
V. Mazayeva
Keyword(s):  
Differential Scanning Calorimetry ◽  
Sample Preparation ◽  
Shelf Life ◽  
Rapid Decline ◽  
Scanning Calorimetry ◽  
Foreign Origin ◽  
The World ◽  
Powder Samples ◽  
Moisture Saturation

Aim. To determine the quality of diterpene glycoside powders, produced in Ukraine using the stevia leaves of plants of domestic and foreign origin. Methods. Differential scanning calorimetry and thermographic analy- sis. Results. It was demonstrated that the increase in the production of powders of diterpene glycosides in the world results in stepping up the requirements to the selection material of stevia and the quality of powders, obtained from its leaves as a fi nal product. The quality of diterpene glycoside powders, produced in Ukraine us- ing the stevia leaves of plants of domestic and foreign origin, was investigated. Conclusions. It was determined that special attention in the analysis of the powder samples of diterpene glycosides should be paid to the sample preparation: increased humidity of the sample promotes a weakening of carbohydrate bonds and rapid decline in their quality. Differential scanning calorimetry allows determining the content of additives, the degree of moisture saturation, and may further be used in the screening of selection samples and forecasting the shelf life of powders of diterpene glycosides.

Sign in / Sign up

Export Citation Format

Share Document