Effect of Season on the Whey Protein Nitrogen Distribution of Pooled Milk

Dellamonica, E. S.; Holden, T.F.; Calhoun, M. J.; Aceto, N.C.

doi:10.3168/jds.s0022-0302(65)88531-9

Cited by 5 publications

(4 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…1). Trends for the individual milk serum proteins were not very marked but values for /?-lg tended to be higher in summer than in winter, which is the opposite of that found by Dellamonica et al (1965), while the pattern for a-la was similar to that for a s2 -casein with a peak value at the end of May being followed by a gradual decline to a minimum in November. Variation in the IPL fraction led to most of the summer samples giving the higher values, while that for BSA was largely within the limits of experimental error.…”

Section: Seasonal Variation In Milk Proteincontrasting

confidence: 57%

See 1 more Smart Citation

The content and composition of protein in creamery milks in south-west Scotland

Davies

Law

1980

Journal of Dairy Research

122

View full text Add to dashboard Cite

The content and composition of protein in milk samples from creameries in south-west Scotland were determined over a period of 12 months. The composition of the whole casein was expressed in terms of a sl -, /?-, K-, a s2 -and y-caseins, and that of the total milk serum protein in terms of /?-lactoglobulins (/?-lg), a-lactalbumins, bovine serum albumin, and a mixture of immunoglobulins, proteose-peptone component 3 and lactoferrin (IPL). Concentrations of the individual caseins varied appreciably and for most, concentration was closely correlated with and showed the same seasonal pattern as total casein concentration. Concentrations of the milk serum proteins also varied but only those of /Mg and the IPL fraction were closely correlated with that of total milk serum protein and seasonal trends were not marked. Relative amounts of the individual proteins, on the other hand, showed smaller variations and so throughout the experimental period the milks contained a protein complex of comparatively constant composition. Because of this comparative constancy it would appear that seasonal variations in milk properties in south-west Scotland are unlikely to be determined to a major extent by milk protein composition, but could be more affected by protein concentration. (1978) show that approximately half of the milk sold off farms in the UK in 1977-78 was utilized for the manufacture of dairy products, with the other half going for liquid sales. Of the milk going to manufacture a considerable proportion, especially in Scotland, was used for the production of cheese, condensed milk, skim-milk powder and casein. The yield of these products depends to an appreciable extent on the protein content of the milk (Zurborg, 1978) and their quality could be influenced by the composition of the protein, i.e. the relative amounts of the various caseins and milk serum proteins present. Values for the contents of total protein, casein and whey protein in commercial milk supplies in England and Wales have been reported by Harding & Royal (1974) and for creamery milks from south-west Scotland by Holt, Muir & Svveetsur (1978), but there appears to be little information on the relative amounts of the individual caseins and milk serum proteins in such milks. Therefore we have carried out a detailed analysis of the protein in creamery milks collected over a period of one year in south-west Scotland and the results are presented here. Statistics published by the Federation of United Kingdom Milk Marketing Boards

show abstract

Section: Seasonal Variation In Milk Proteincontrasting

confidence: 57%

“…Dellamonica et al 1965;Chapman & Burnett, 1972;De Koning, Koops & Van Rooijen, 1974;. Sometimes the variations have been associated with changes in levels of total protein and casein.…”

Section: Seasonal Variation In Milk Proteinmentioning

confidence: 99%

The content and composition of protein in creamery milks in south-west Scotland

Davies

Law

1980

Journal of Dairy Research

122

View full text Add to dashboard Cite

show abstract

“…Nevertheless, another issue was the variation in whey protein content in milk samples. It has been reported that whey protein content in raw milk may fluctuate due to seasonality [91][92][93][94]. In this study, the raw milk samples for the experiments were collected during wintertime.…”

Section: Potential Limitations Of the Studymentioning

confidence: 99%

Effect of Pulsed Electric Field (PEF) on Bacterial Viability and Whey Protein in the Processing of Raw Milk

et al. 2021

View full text Add to dashboard Cite

There is growing concern regarding the nutritional value of processed food products. Although thermal pasteurization, used in food processing, is a safe method and is widely applied in the food industry, food products lack quality and nutritional value because of the high temperatures used during pasteurization. In this study, the effect of pulsed electric field (PEF) processing on whey protein content and bacterial viability in raw milk was evaluated by changing the PEF strength and number of pulses. For comparison, traditional pasteurization techniques, such as low-temperature long-time (LTLT), ultra-high temperature (UHT), and microfiltration (MF), were also tested for total whey protein content, bacterial activity, and coliforms. We found that, after treatment with PEF, a significant decrease in total bacterial viability of 2.43 log and coliforms of 0.9 log was achieved, although undenatured whey protein content was not affected at 4.98 mg/mL. While traditional pasteurization techniques showed total bacterial inactivation, they were detrimental for whey protein content: β-lactoglobulin was not detected using HPLC in samples treated with UHT. LTLT treatment led to a significant decrease of 75% in β-lactoglobulin concentration; β-lactoglobulin content in milk samples treated with MF was the lowest compared to LTLT and UHT pasteurization, and ~10% and 27% reduction was observed.

show abstract

“…L'étalonnage fait à partir des protéines totales peut être influencé par Ia variation du rapport des teneurs en protéines solubles et des caséines. Les variations en fonction de la période ont été étudiées par différents auteurs (HARLAND et al, 1955;DELLAMONICA et al, 1965 ;GRAPPINet JEUNET,1976 a). Le rapport varie beaucoup avec l'individu, la race et le stade de lactation.…”

Section: Les Méthodes De Dosageunclassified