Interfacial Energies in Milk, Influence of Milk Proteins on Interfacial Tension between Butter Oil and Various Aqueous Phases

SUMMARYA method capable of determining the interfacial tension (γ) of individual emulsified liquid drops has been investigated and applied to a study of the surface properties of milk fat globules. Measurements on several organic liquids in bulk against water were made to validate and standardize the technique. With one exception, results agreed well with literature values, but the reproducibility of measurements was not as good as that of other, standard, methods. Measurements performed on small drops were affected by several factors and precision was not high.The influence of different milk treatments upon the interfacial tension of milk fat globules was studied. Agitation of milk had the effect of increasing γ while the effect was reversed upon allowing agitated milk to stand. Dilution of normal milk with water resulted in an increase in γ while acidification and alkalization produced a decrease. Pasteurization of raw milk caused a slight, non-significant decrease. Values of γ were low, 1–2 mN m-1, irrespective of the nature of the milk treatment and were an order of magnitude smaller than those obtained for interfaces of butter oil and milk protein solutions. The results support the concept of a 2-layer membrane and suggest that changes in γ follow mainly the adsorption/desorption of surface active components in the outer hydrophilic layer of the globule membrane. An inner, firmly bound lipophilic layer, resistant to many different milk treatments, appears to determine the overall low γ value under most conditions.

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Formation and Structure of Casein Micelles in Lactating Mammary Tissue

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100067741 ◽

1970 ◽

Vol 28 ◽

pp. 150-151

Author(s):

Robert J. Carroll ◽

Marvin P. Thompson ◽

Harold M. Farrell

Keyword(s):

Size Distribution ◽

G Protein ◽

Milk Proteins ◽

Mammary Tissue ◽

Colloidal System ◽

Casein Micelles ◽

The Stability

Milk is an unusually stable colloidal system; the stability of this system is due primarily to the formation of micelles by the major milk proteins, the caseins. Numerous models for the structure of casein micelles have been proposed; these models have been formulated on the basis of in vitro studies. Synthetic casein micelles (i.e., those formed by mixing the purified αsl- and k-caseins with Ca2+ in appropriate ratios) are dissimilar to those from freshly-drawn milks in (i) size distribution, (ii) ratio of Ca/P, and (iii) solvation (g. water/g. protein). Evidently, in vivo organization of the caseins into the micellar form occurs in-a manner which is not identical to the in vitro mode of formation.

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GENE ACTIVATION IN MAMMARY CELLS

Acta Endocrinologica ◽

10.1530/acta.0.071s346 ◽

1972 ◽

Vol 71 (2_Suppla) ◽

pp. S346-S368 ◽

Cited By ~ 4

Author(s):

Roger W. Turkington ◽

Nobuyuki Kadohama

Keyword(s):

Cell Differentiation ◽

Gene Transcription ◽

Hormonal Regulation ◽

Gene Activation ◽

Milk Proteins ◽

Mouse Mammary Gland ◽

Nuclear Proteins ◽

Mammary Cells ◽

Alveolar Cells ◽

Mammary Cell

ABSTRACT Hormonal activation of gene transcription has been studied in a model system, the mouse mammary gland in organ culture. Transcriptive activity is stimulated in mammary stem cells by insulin, and in mammary alveolar cells by prolactin and insulin. Studies on the template requirement for expression of the genes for milk proteins demonstrate that DNA methylation has an obligatory dependence upon DNA synthesis, but is otherwise independent from hormonal regulation of mammary cell differentiation. Incorporation of 5-bromo-2′deoxyuridine into DNA selectively inhibits expression of the genes for specific milk proteins. Undifferentiated mammary cells activate the synthesis of specific acidic nuclear proteins when stimulated by insulin. Several of these induced acidic nuclear proteins are undetectable in unstimulated undifferentiated cells, but appear to be characteristic components of the nuclei of differentiated cells. These results indicate that mammary cell differentiation is associated with a change in acidic nuclear proteins, and they provide evidence to support the concept that acidic nuclear proteins may be involved in the regulation of gene transcription and of mammary cell differentiation.

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Investigation of heat and matrix effect on milk proteins’ allergenicity and the development of hypoallergenic food products

10.26226/morressier.5acc8ad0d462b8028d89abaf ◽

2018 ◽

Author(s):

Hande Suer

Keyword(s):

Matrix Effect ◽

Milk Proteins ◽

Food Products

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Perbandingan Karakteristik Surfaktan Metil Ester Sulfonat dan Sodium Lauril Sulfonat sebagai Bahan Emulsifier

Jurnal Riset Teknologi Industri ◽

10.26578/jrti.v9i2.1715 ◽

2016 ◽

Vol 9 (2) ◽

pp. 167-176

Author(s):

Eldha Sampepana ◽

Paluphy Eka Yustini ◽

Aditya Rinaldi ◽

Amiroh Amiroh

Keyword(s):

Fatty Acids ◽

Surface Tension ◽

Methyl Ester ◽

Interfacial Tension ◽

Palm Oil ◽

Emulsion Stability ◽

Raw Material ◽

Enzymatic Method

Surfactant which is used as raw emulsifier in an industry activity such as Sodium Lauryl Sulfonate is a raw material import, it is petroleum derivative which is not renewable and may cause pollution to the environment, because it is not degraded and are carcinogenic. The purpose of the research is to compare the characteristics of the Quaternary methyl ester sulfonat (MES) and Sodium Lauryl Sulfonat (SLS) as emulsifier. First, make the MES by filtering and eliminating fatty acids of palm oil, then process the MES with enzymatic method become methyl ester, then react it in sulfonation and metanolization process, and also neutralized with NaOH. Next, the MES experiment is compared with SLS and existing MES in the market. The results show that surfactants MES experiment has value hidrofil lipofil balance (HLB) interfacial tension and emulsion stability greater than MES in the market and SLS. And the surface tension of MES experiment is larger than MES in the market, but smaller compared to SLS.ABSTRAKSurfaktan yang digunakan sebagai bahan baku emulsifer dalam aktivitas suatu industri pada saat ini seperti Sodium Lauril Sulfonat merupakan bahan baku import yang merupakan turunan dari minyak bumi, dengan sifat tidak dapat diperbaharui dan dapat menimbulkan pencemaran terhadap lingkungan karena tidak mudah terdegradasi serta bersifat karsinogenik. Metil ester sulfonat dari bahan minyak sawit merupakan surfaktan dengan sifat mudah terdegradasi yang perlu diketahui karakteristiknya. Penelitian bertujuan untuk membandingkan karakteristik surfaktan metil ester sulfonat (MES) dan Sodium Lauril Sulfonat (SLS) sebagai bahan emulsifier. Mula-mula dilakukan pembuatan MES dengan cara menyaring dan menghilangkan asam lemak minyak sawit terlebih dahulu, kemudian diolah menjadi metil ester secara enzimatis, lalu direaksikan secara sulfonasi dan metanolisis, serta dinetralkan dengan NaOH. Selanjutnya MES hasil percobaan dibandingkan dengan SLS dan MES yang ada dipasaran. Hasil penelitian menunjukkan bahwa surfaktan MES memiliki nilai hidrofil lipofil balance (HLB) tegangan antar muka dan stabilitas emulsi lebih besar apabila dibandingkan dengan MES di pasaran dan SLS, kecuali nilai stabilitas emulsi antara MES dan SLS sama. Dan tegangan permukaan MES hasil percobaan, lebih besar dibandingkan dengan MES dipasaran, dan lebih kecil dibandingkan dengan SLS. Kata kunci : Metil ester sulfonat, hidrofil lipofil balance, emulsifier, sodium lauril sulfonat , stabilitas emulsi

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The importance of stock herding and dairying in the Neolithic Balkans and the subsistence diversity

10.31219/osf.io/yptjn ◽

2020 ◽

Author(s):

Darko Stojanovski ◽

Ivana Živaljević ◽

Vesna Dimitrijević ◽

Julie Dunne ◽

Richard Evershed ◽

...

Keyword(s):

Milk Proteins ◽

Domestic Animal ◽

Dental Calculus ◽

Isotopic Study ◽

Radiocarbon Dates ◽

The Balkans ◽

Animal Remains ◽

New Information ◽

Archaeological Materials ◽

Ceramic Vessels

The application of biomolecular techniques to archaeological materials from the Balkans is providing valuable new information on the prehistory of the region. This is especially relevant for the study of the neolithisation process in SE Europe, which gradually affected the rest of the continent. Here, to answer questions regarding diet and subsistence practices in early farming societies, we combine organic residue analyses of archaeological pottery, taxonomic and isotopic study of domestic animal remains and biomolecular analyses of human dental calculus. The results from the analyses of the lipid residues from pottery suggest that milk was processed in ceramic vessels. Dairy products were shown to be part of the subsistence strategies of the earliest Neolithic communities in the region but were of varying importance in different areas of the Balkan. On the other hand, we did not confidently detect any milk proteins within the dental calculus. The molecular and isotopic identification of meat, dairy, plants and beeswax in the pottery lipids also provided insights into the diversity of diet in these early Neolithic communities. We also present the first compound-specific radiocarbon dates for the region, obtained directly on absorbed organic residues extracted from pottery, identified as dairy lipids.

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