Factor analysis as a tool to estimate association among individual proteins and other milk components with casein micelle size and cheese yield

ABSTRACT The present study attempted to identify individual milk proteins and other milk components that are associated with casein micelle size (CMS) and dry matter cheese yield (DMCY) using factor analysis. Here, we used 140 bulk tank milk samples from different farms. Milk composition was determined using a Fourier transform infrared equipament. The individual milk proteins were (αS-casein, β-casein, κ-casein, β-lactoglobulin and α-lactoalbumin) measured by their electrophoretic profile. The CMS was estimated by photon correlation spectroscopy, and the DMCY was determined using reduced laboratory-scale cheese production. Factor analysis partitioned the milk components into three groups that, taken together, explain 68.3% of the total variance. The first factor was defined as “CMS”, while the second as “DMCY” factor, based on their high loadings. The CMS was positively correlated with protein, casein, non-fat solids and αS-casein and negatively associated with κ-casein and β-lactoglubulin. DMCY was positively correlated with fat, protein, casein, total solids and negatively correlated with αs-casein. These results indicate that the variation of individual milk proteins may be an important aspect correlated to milk quality and cheese production.

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Association of casein micelle size and enzymatic curd strength and dry matter curd yield

Ciência Rural ◽

10.1590/0103-8478cr20180409 ◽

2019 ◽

Vol 49 (3) ◽

Author(s):

Denise Ribeiro de Freitas ◽

Fernando Nogueira de Souza ◽

Jamil Silvano de Oliveira ◽

Diêgo dos Santos Ferreira ◽

Cristiane Viana Guimarães Ladeira ◽

...

Keyword(s):

Fixed Effects ◽

Dry Matter ◽

Linear Models ◽

Favorable Effect ◽

Casein Micelle ◽

Casein Micelles ◽

Micelle Size ◽

Milk Protein Content ◽

Bulk Tank ◽

Cheese Production

ABSTRACT: The aim of the present study was to explore the association between milk protein content and casein micelle size and to examine the effects of casein micelle size on enzymatic curd strength and dry matter curd yield using reduced laboratory-scale cheese production. In this research, 140 bulk tank milk samples were collected at dairy farms. The traits were analyzed using two linear models, including only fixed effects. Smaller micelles were associated with higher κ-casein and lower αs-casein contents. The casein micellar size (in the absence of the αs-casein and κ-casein effects) did not affect the enzymatic curd strength; however, smaller casein micelles combined with higher fat, lactose, casein and κ-casein contents exhibited a favorable effect on the dry matter curd yield. Overall, results of the present study provide new insights into the importance of casein micelle size for optimizing cheese production.

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The Two-Stage Coagulation of Milk Proteins in the Minimum of the Heat Coagulation Time-pH Profile of Milk: Effect of Casein Micelle Size

Journal of Dairy Science ◽

10.3168/jds.s0022-0302(00)74892-2 ◽

2000 ◽

Vol 83 (3) ◽

pp. 378-386 ◽

Cited By ~ 46

Author(s):

J.E. O’Connell ◽

P.F. Fox

Keyword(s):

Milk Proteins ◽

Casein Micelle ◽

Two Stage ◽

Coagulation Time ◽

Ph Profile ◽

Micelle Size

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The determination of casein micelle size distribution in skim milk by chromatography and photon correlation spectroscopy

Biochimica et Biophysica Acta (BBA) - Protein Structure and Molecular Enzymology ◽

10.1016/0167-4838(83)90192-9 ◽

1983 ◽

Vol 748 (3) ◽

pp. 453-459 ◽

Cited By ~ 26

Author(s):

M.C.A. Griffin ◽

M. Anderson

Keyword(s):

Size Distribution ◽

Photon Correlation Spectroscopy ◽

Skim Milk ◽

Correlation Spectroscopy ◽

Casein Micelle ◽

Photon Correlation ◽

Micelle Size

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Variation in Dairy Milk Composition and Properties Has Little Impact on Cheese Ripening: Insights from a Traditional Swedish Long-Ripening Cheese

Dairy ◽

10.3390/dairy2030027 ◽

2021 ◽

Vol 2 (3) ◽

pp. 336-355

Author(s):

Hasitha Priyashantha ◽

Monika Johansson ◽

Maud Langton ◽

Sabine Samples ◽

Shishanthi Jayarathna ◽

...

Keyword(s):

Milk Composition ◽

Casein Micelle ◽

Cheese Making ◽

Cheese Ripening ◽

Ripening Time ◽

Micelle Size ◽

Proteolytic Activities ◽

Time Required ◽

Minimum Criteria ◽

Dairy Milk

The monthly variation in raw dairy silo milk was investigated and related to the ripening time of the resulting cheese during an industrial cheese-making trial. Milk composition varied with month, fat and protein content being lowest in August (4.19 and 3.44 g/100 g, respectively). Casein micelle size was largest (192–200 nm) in December–February and smallest (80 nm) in August. In addition, SCC, total bacteria count, proteolytic activities, gel strength, and milk fatty acid composition were significantly varied with month. Overall sensory and texture scores of resulting cheese were mainly influenced by plasmin and plasminogen activity, indicating the importance of native proteolytic systems. Recently, concepts based on the differentiated use of milk in dairy products have been suggested. For the investigated cheese type, there might be little to gain from such an approach. The variation in the investigated quality characteristics of the dairy milk used for cheese making had little effect on cheese ripening in our study. In contrast to our hypothesis, we conclude that as long as the quality of the milk meets certain minimum criteria, there are only weak associations between cheese milk characteristics and the time required for the development of aroma and texture in the cheese. To find answers behind the observed variation in cheese ripening time, studies on the effects of process parameters are needed.

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Fixation of bovine casein micelles for chromatography on controlled pore glass

Journal of Dairy Research ◽

10.1017/s0022029900032933 ◽

1984 ◽

Vol 51 (4) ◽

pp. 615-622 ◽

Cited By ~ 10

Author(s):

Malcolm Anderson ◽

Mary C. A. Griffin ◽

Carolyn Moore

Keyword(s):

Skim Milk ◽

Correlation Spectroscopy ◽

Casein Micelle ◽

Elution Profile ◽

Casein Micelles ◽

Controlled Pore Glass ◽

Micelle Size ◽

Pore Glass ◽

Peak Areas ◽

Profile Area

SummaryGlutaraldehyde was used to fix the size distribution of casein micelles in skim milk before their fractionation by permeation chromatography on controlled pore glass. The effect of fixation was assessed by comparing the size and absorption profile for column fractions obtained from samples which were fixed before fractionation with those of unfixed samples and of samples that were fixed only after completion of chromatography. Micelle size was determined by photon correlation spectroscopy. Column profiles were obtained from absorption measurements at 340 nm and after pronase digestion at 280 nm to determine relative protein concentration. For comparative purposes the elution profile was divided into 4 peak areas, of which I-III contained most of the casein micelles, and IV consisted of the smallest micelles, soluble casein and whey protein. Average micelle size was unaltered by fixation but was larger in fractions from prefixed skim milk than those from unfixed samples. Fixation increased the absorbance readings but the elution profile at 340 nm for peak areas I-III was essentially the same for unfixed fractions and those obtained when fixation was applied after chromatography. However, areas I-III accounted for a much larger proportion of the total profile area when the latter procedure was followed. Total profile area increased with fixation time and temperature but this did not affect the elution profile. The results indicate that fixation with glutaraldehyde does not induce artefactual changes in casein micelle size.

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Physicochemical transformation of milk components and release of foot-and-mouth disease virus

Journal of Dairy Research ◽

10.1017/s0022029900032489 ◽

1983 ◽

Vol 50 (1) ◽

pp. 17-25 ◽

Cited By ~ 2

Author(s):

John H. Blackwell ◽

Peter D. McKercher ◽

Frank V. Kosikowski ◽

Leland E. Carmichael ◽

Ronald C. Gorewit

Keyword(s):

Disease Virus ◽

Milk Fat ◽

Skim Milk ◽

Foot And Mouth Disease ◽

Mouth Disease ◽

Casein Micelle ◽

Physicochemical Transformation ◽

Mouth Disease Virus ◽

Milk Components ◽

The Individual

SummaryPossible mechanisms for protective roles of milk components on footand-mouth disease virus present in the milk of infected cows were examined. Light scattering bands collected from Ficoll-sucrose gradient fractions of skim-milk contained membrane-limited structures but these were non-infectious for bovine kidney cells, lnfectivity titres in buttermilk higher than those of the original cream or butter suggested association of virus with milk fat globules. Increased infectivity titres in skim-milk after treatment with SDS suggested release of virus particles from dissociated casein micelle subunits. Chelating agents, de-emulsifying agents and trypsin, which alter the structure of the individual milk components casein, lipid and milk fat globule membrane were without effect on infectivity titres.

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Effect of heat treatment on casein micelle profiles obtained by controlled pore-glass chromatography

Journal of Dairy Research ◽

10.1017/s0022029900033100 ◽

1986 ◽

Vol 53 (4) ◽

pp. 585-593 ◽

Cited By ~ 2

Author(s):

Malcolm Anderson ◽

Carolyn Moore ◽

Mary C. A. Griffin

Keyword(s):

Heat Treatment ◽

Correlation Spectroscopy ◽

Holding Time ◽

Casein Micelle ◽

Casein Micelles ◽

Photon Correlation ◽

Controlled Pore Glass ◽

Micelle Size ◽

Whole Milk ◽

Pore Glass

SummaryThe effect of heat treatment on the profiles of casein micelles obtained at 340 and 280 nm from controlled pore-glass chromatography of milk was studied in a series of unhomogenized whole milk samples which had been heated in a pilot plant at 75, 90, 105, 120, 135 and 150 °C for holding times of 4, 16, 32, 72, 150 and 300 s. A second experiment was carried out in which whole milk was preheated at temperatures between 70 and 110 °C for 13, 60 and 180 s before being treated at 120 °C for 4 s or 150 °C for 16 s. The average micelle size in some of the samples was determined by photon correlation spectroscopy. Profiles were divided into four fractions in which micelle size decreased from fraction 1 to fraction 4. The dimensions of these fractions were expressed in terms of size relative to that of the total profile. Fraction 4 was not affected by any of the heat treatments. Fractions 1–3 were significantly affected only by temperatures above 120 °C. Between 120 and 150 °C fraction 1 increased significantly while fractions 2 and 3 showed a corresponding decrease. Holding time affected fraction 1 only above 120 °C. For fraction 2 there was no effect in < 32 s at temperatures less than 150 °C. Fraction 3 was the most sensitive to changes in holding time, but no effect was observed below 105 °C. Average micelle size measurements indicated that a substantial size increase only occurred in those milks heated at 135 °C for longer than 16 s and in all the samples at 150 °C. To assess whether this increase in micelle size was reversible, samples were dialysed against a 70 mm-NaCl solution containing 10 mm-EDTA and then separated by column chromatography on Sephacryl S-300. The proportion of materials which was undissociated by dialysis remained unchanged for temperatures below 120 °C, but progressively increased with treatments more severe than 120 °C for 16 s. Column profiles were not influenced by variations in the conditions of preheating

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Importance of casein micelle size and milk composition for milk gelation

Journal of Dairy Science ◽

10.3168/jds.2009-2856 ◽

2010 ◽

Vol 93 (4) ◽

pp. 1444-1451 ◽

Cited By ~ 86

Author(s):

M. Glantz ◽

T.G. Devold ◽

G.E. Vegarud ◽

H. Lindmark Månsson ◽

H. Stålhammar ◽

...

Keyword(s):

Milk Composition ◽

Casein Micelle ◽

Micelle Size ◽

Milk Gelation

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Validation of the Chinese Version of the Multidimensional Workaholism Scale

Journal of Career Assessment ◽

10.1177/1069072721994272 ◽

2021 ◽

pp. 106907272199427

Author(s):

Yan Xu ◽

Chaoping Li

Keyword(s):

Factor Analysis ◽

Reliability And Validity ◽

Well Being ◽

Chinese Version ◽

Full Time ◽

Work Family Conflict ◽

Working Adults ◽

Work Family ◽

The Individual ◽

Two Stages

The aim of this study was to translate the Multidimensional Workaholism Scale (MWS) into Chinese and then test its reliability and validity among full-time Chinese employees in two stages. In Study 1 ( N = 220), the MWS was translated and exploratory factor analysis was conducted resulting in a four-factor solution consistent with the original MWS: motivational, cognitive, emotional, and behavioral. In Study 2 ( N = 425), confirmatory factor analysis showed that a four-factor, bifactor model was the best fit for the data. Configural, metric, and scalar invariance models were tested which demonstrated that the Chinese version of the MWS did not differ across gender, age, and job position groups. Finally, workaholism and engagement were related and distinct from one another, and they correlated with emotional exhaustion, work-family conflict and life well-being uniquely. This study indicated that the Chinese version of the MWS is a valid and reliable tool for Chinese employees, and this has important practical implications for the individual health and career development of Chinese working adults.

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