OSMOTIC RELATIONSHIPS IN THE HEN'S EGG AS DETERMINED BY RELATIVE VAPOR PRESSURES

In a recent paper Howard (1932) claims to have shown, by three methods, that the "expected" osmotic equilibria exist between the yolk and white of a hen's egg. Johlin (1933) has criticized her technique of cryhydric measurement and re-asserted that the yolk and white of an egg hive different values for depression of freezing point. Although Needham (1931) and Meyerhof (1931) have considered the possibility of the outer layer of yolk having a lower osmotic pressure than the inner, Howard gives no experimental evidence indicating the existence of an osmotic gradient within the yolk. The methods she used being apparently incapable of showing the difference in osmotic pressure between the whole yolk and the whole white of an egg were presumably unable also to detect the osmotic gradient in the yolk. Grollman's (1931) criticisms of the Hill thermo-electric method for the measurement of vapour pressures when employed with viscous solutions were repeated by Howard, with no other evidence than that it gave results which disagreed with her own. In particular, Bateman's low vapour pressure depression found in mixtures of egg yolk and egg white are declared to be incompatible with high vapour pressure depressions for yolk. It is strange that in the differentiation of the properties of egg yolk and white so many authors should have considered the yolk as homogeneous. It is a well-known fact that the formation of an egg yolk occurs by daily deposits in the ovary of the hen. These extend over several days and that the integrity of the daily deposit is maintained more or less for many days is evidenced by observation of the spherical zones in the yolk of a frozen egg that has been sectioned. Also it is easy to withdraw from the centre of the yolk, using a fine pipette, white yolk which is different chemically from the surrounding yellow yolk. Since no membrane is known to separate these two kinds of yolk nor the daily deposit of yolk, the existence of this non-homogeneity within the yolk must be an indication of the slowness of equilibration inside a hen's egg. Hence, when one speaks of the difference in osmotic pressure of average egg white and average egg yolk, no conclusions can be drawn logically regarding the difference in osmotic pressure on opposite sides of the vitelline membrane. As the Hill thermoelectric method of measuring vapour pressure requires but small quantities of solution, it was of interest to use this micro method to study the difference in osmotic pressures of samples of yolk and white obtained on opposite sides of the membrane.

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New Allergens from Hen’s Egg White and Egg Yolk

International Archives of Allergy and Immunology ◽

10.1159/000234653 ◽

1988 ◽

Vol 87 (1) ◽

pp. 81-86 ◽

Cited By ~ 33

Author(s):

B.J. Walsh ◽

D. Barnett ◽

R.W. Burley ◽

C. Elliott ◽

D.J. Hill ◽

...

Keyword(s):

Egg Yolk ◽

Egg White ◽

Hen’S Egg

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Differences in allergic symptoms after the consumption of egg yolk and egg white

Allergy Asthma & Clinical Immunology ◽

10.1186/s13223-021-00599-2 ◽

2021 ◽

Vol 17 (1) ◽

Author(s):

Kei Uneoka ◽

Satoshi Horino ◽

Ayafumi Ozaki ◽

Haruka Aki ◽

Masako Toda ◽

...

Keyword(s):

Respiratory Symptoms ◽

Gastrointestinal Symptoms ◽

Food Challenge ◽

Egg Yolk ◽

Egg White ◽

Positive Group ◽

Hen’S Egg ◽

Common Causes ◽

Organ Specific ◽

Specific Symptoms

AbstractHen’s eggs are one of the most common causes of food allergy. Although hen’s eggs are known to cause more gastrointestinal symptoms than other foods, it is not known whether there is a difference in organ-specific symptoms between egg yolk (EY) and egg white (EW). The present study aimed to determine whether there are organ-specific differences in the immediate symptoms of EY and EW in patients with hen’s egg allergies. We retrospectively investigated the immediate symptoms and treatment contents of those who had a positive result in an oral food challenge (OFC) of boiled whole EY or 10 g of boiled EW in our hospital from January 2013 to July 2019. We compared 80 patients in the EY-OFC-positive group with 106 patients in the EW-OFC-positive group. The EY-OFC-positive group had significantly fewer respiratory symptoms and significantly more gastrointestinal symptoms than the EW-OFC-positive group and had significantly more gastrointestinal symptoms only. In terms of treatment, significantly fewer patients in the EY-OFC-positive group required beta 2-agonist inhalation, and a significantly higher proportion of patients did not require treatment. Compared to EW, EY is more likely to cause gastrointestinal symptoms and less likely to cause respiratory symptoms. It may be necessary to discriminate between EY and EW allergy during diagnosis.

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The Relations Between Yolk and White in the Hen'S Egg

Journal of Experimental Biology ◽

10.1242/jeb.8.3.293 ◽

1931 ◽

Vol 8 (3) ◽

pp. 293-311

Author(s):

MICHAEL SMITH ◽

JAMES SHEPHERD

Keyword(s):

Steady State ◽

Alternative Explanation ◽

Water Movement ◽

Egg Yolk ◽

Egg White ◽

Effect Of Temperature ◽

Vitelline Membrane ◽

Osmotic Concentration ◽

Freezing Points ◽

Hen’S Egg

1. The freezing-points of white and yolk in the hen's egg gradually approach equality when the egg is kept for long periods; and the rate of the process of equilibration is rapid at first but becomes very slow as equality is more closely approached. 2. Between 0° and 25° C. the rate of equilibration has a temperature coefficient (Q 10) of from 1.5 to 2. At 25° C. equality of freezing-points is reached after about 70 days. 3. Equilibration is achieved partly by the passage of water across the vitelline membrane from white to yolk, but partly also by more complicated changes of osmotic concentration occurring more or less independently in white and yolk. 4. The recovery of hypertony by a yolk, previously diluted by immersion in water, when it is replaced in egg-white can, be explained on the basis of a temporary heterogeneity of the diluted yolk, and this explanation is supported by experimental evidence. 5. The rate of equilibration is much greater when the separated yolk is placed in mixed egg-white than in the intact egg, but since it is also greater in thin white than in thick white, and greater again in the white dialysate, the structure and viscosity of the white are probably important factors. 6. There is evidence of an appreciable resistance to water-movement both in egg-white and in egg-yolk. 7. In hypotonic or hypertonic aqueous solutions of glucose or glycerol, or in Ringer's solution, the rate of equilibration is greater than in egg-white and many times greater than in the intact egg. Water is taken up by the yolk both from hypotonic and hypertonic solutions of Ringer, within the range δ = 0.10° to 1.20° C., at a rate which increases the further the solution is removed from the point of isotony. 8. Evidence that the apparent disequilibrium in intact eggs is not a steady state maintained by a "Lebenswirkung," is afforded by: (i) the form of the equilibration curves, which strongly suggest the slow attainment of an equilibrium by diffusion, rather than a steady state terminated by death; (ii) the temperature relations of equilibration, which are consistent with the former assumption, but which do not agree at all with the effect of temperature on the viability of fertile eggs; (iii) the absence of any tendency of the yolk to maintain its hypertony when the white is concentrated by rapid evaporation; (iv) the alternative explanation for the recovery of hypertony by diluted yolks, which was the most crucial evidence for the existence of a steady state maintained by the expenditure of energy.

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Examination of hen’s egg yolk, egg white, and ovomucoid specific IgE level as the negative predictive marker of the oral food challenge for heated hen’s egg yolk

Nihon Shoni Arerugi Gakkaishi The Japanese Journal of Pediatric Allergy and Clinical Immunology ◽

10.3388/jspaci.31.705 ◽

2017 ◽

Vol 31 (5) ◽

pp. 705-713

Author(s):

Airi Kunitomo ◽

Akiko Aota ◽

Saya Yamada ◽

Ryohei Suzuki ◽

Nagatoshi Sagara ◽

...

Keyword(s):

Food Challenge ◽

Predictive Marker ◽

Egg Yolk ◽

Specific Ige ◽

Egg White ◽

Oral Food Challenge ◽

Hen’S Egg

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OSMOTIC RELATIONSHIPS IN THE HEN'S EGG, AS DETERMINED BY COLLIGATIVE PROPERTIES OF YOLK AND WHITE

The Journal of General Physiology ◽

10.1085/jgp.16.1.107 ◽

1932 ◽

Vol 16 (1) ◽

pp. 107-123 ◽

Cited By ~ 6

Author(s):

Evelyn Howard

Keyword(s):

Osmotic Pressure ◽

Freezing Point ◽

Marked Change ◽

Egg Yolk ◽

Ice Formation ◽

Vital Activity ◽

Hen’S Egg ◽

Vapor Pressure Measurements ◽

Osmotic Pressure Difference

The osmotic pressure of the yolk and white of the hen's egg have been shown to be identical, by means of direct freezing point determinations, dialyses, and vapor pressure measurements. Dialysates of egg yolk slow the rate of ice formation compared with NaCl solutions. They also show a marked change of freezing rate as the freezing point is approached. The anomalous freezing behavior of this material may lead to errors in the determination of the true freezing point which would tend to make the value for the yolk erroneously low. The postulate of a vital activity at the yolk membrane maintaining an osmotic pressure difference is thus shown to be unnecessary, since a simple osmotic equilibrium exists between the yolk and the white.

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