Search results for "milk proteins"
showing 9 items of 39 documents
Proteomics for milk proteins characterization in Girgentana goat breed
2013
Proteomics has been widely used to characterize milk protein content in livestock species and unravel protein biological functions. The aim of this work was to characterize the Girgentana goat breed whole milk and milk fraction proteins by two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and mass spectrometry. Bulk milk samples from two farms locate in Palermo and Agrigento (Sicily) areas were collected during the early stage of lactation. Initially, 2D-PAGE and protein detection protocols were set-up. In particular, 2D-PAGE analyses were carried out on whole milk using 18-cm IPG strips ranging from pH 3-10 and 4-7 and 12.5% polyacrylamide gel for first and the second dimension …
Effects of Sulla forage (Sulla coronarium L.) on the oxidative status and milk polyphenol content in goats
2015
Abstract Twelve milking Girgentana goats were allocated into 3 groups and fed 3 diets ad libitum in a 3 × 3 Latin square design with 3 periods. The diets were Sulla fresh forage ad libitum (SUL), Sulla fresh forage ad libitum and 800 g/d of barley meal (SULB), and mixed hay ad libitum and 800 g/d of barley meal (HB). Changes were observed in total polyphenol intake, plasma oxidative status, plasma polyphenol content, metabolic status, milk polyphenol content, and total antioxidant capacity. The fresh forage diets (SUL and SULB) increased dry matter, total polyphenol, nontannic polyphenol and tannin intakes, and the milk total protein, casein, milk total polyphenols, and milk free polyphenol…
Determination of cow’s milk in non-bovine and mixed cheeses by capillary electrophoresis of whey proteins in acidic isoelectric buffers
2000
An improved method for the determination of cow's milk in non-bovine cheese is reported: electrophoresis of whey proteins in acidic, isoelectric buffers. Two background electrolytes (BGEs) have been tested: (i) 50 mM iminodiacetic acid (pH=isoelectric point=2.30 at 25 degrees C), 0.5% hydroxyethylcellulose, 0.1% Tween 20 and 6 M urea (apparent pH 3.1), E=300 V/cm, for the separation of alpha-lactalbumins (alpha-LAs); (ii) a BGE with the same composition, but supplemented with 10% Tween 20, E=450 V/cm, for the fractionation of beta-lactoglobulins (beta-LGs). Surfactants have a discriminating effect on the retention behaviour of the bovine alpha-LA and beta-LG proteins, owing to the different…
The impact of whey protein preheating on the properties of emulsion gel bead
2014
Thermal treatment effect (70 or 80 °C for 5 or 30 min) was evaluated on functional properties of whey protein isolate (WPI) dispersions used for the development of novel vitamin A delivery systems based on emulsion gel beads. This process combines an (O/W) emulsion diluted by a polysaccharide solution and a cold-set gelation induced by salt addition. Pre-heated WPI had a significant impact on the denaturation degree and on the surface hydrophobicity, respectively studied by differential scanning calorimetry and fluorescence. Stronger heating conditions (i.e. duration or temperature) induced complete denaturation, an increase of surface hydrophobicity and of viscosity. Under these conditions…
Flavour retention and release from protein solutions
2006
International audience; This paper briefly presents the main results obtained up to now on protein–flavour binding and release in relation with flavour perception. Among the food proteins, β-lactoglobulin is the most extensively studied for its binding properties, which involve both hydrophobic and hydrogen binding. Recent developments using molecular modelling and Quantitative Structure–Activity Relationship confirmed the existence of two different binding sites for flavour compounds on β-lactoglobulin. During the aroma release process in the mouth, not only free aroma compounds are released but also those reversibly bound by the protein, pointing out the fact that flavour perception is on…
Fecal Calprotectin in Self-Reported Milk Intolerance: Not Only Lactose Intolerance
2023
The hypothesis is that inflammatory/allergic conditions should be considered in self-reported milk intolerance (SRMI) patients who test negative and/or are asymptomatic at Lactose Hydrogen Breath Test (LHBT). We analyzed fecal calprotectin (FCP) values in SRMI patients to investigate the frequency of a “positive” intestinal inflammation marker and its correlation with lactose tolerance/intolerance. Data from 329 SRMI patients were retrospectively analyzed; according to the positive/negative results (maldigester/digester) and the presence/absence of symptoms reported during LHBT (intolerant/tolerant), patients were divided into: ‘lactose tolerants’ (n. 104), ‘ma…
Interaction of fluoride ions with milk proteins studied by gel filtration
1992
The interaction of fluoride ions with the bovine milk protein a-lactalbumin, type 1 a-casein, (3-casein, and K-casein was studied at pH 6.6, 5.5 and 3.9. At pH 6.6 and 5.5 fluoride ions do not combine with any of these protein. However, at pH 3.9 they combine with a-lactalbumin.
Recent advances in the application of microbial transglutaminase crosslinking in cheese and ice cream products: A review
2018
Microbial transglutaminase (MTGase) has been currently utilized to form new food structures and matrices with high physicochemical stability. Incorporation of this multi-functional enzyme into structural composition of milk protein-based products, such as cheese and ice cream, can not only be a successful strategy to improve their nutritional and technological characteristics through intramolecular cross-linking, but also to reduce the production cost by decreasing fat and stabilizer contents. The recent research developments and promising results of MTGase application in producing functional formulations of cheese and ice cream with higher quality characteristics are reviewed. New interest…
Transferrin gene expression in the mammary gland of the rat. The enhancing effect of 17 beta-oestradiol on the level of RNA is tissue-specific.
1993
We have investigated the physiological factors which regulate transferrin gene expression in the mammary gland of the rat. Our studies by dot blot analysis have demonstrated that multiple doses of 17β-oestradiol (OE2; 0·5 mg/kg per day for 3 days) elicit a specific 3·5-fold increase in the transferrin mRNA levels in the mammary glands of virgin rats. The hormonal action of OE2 in mammary tissue was specific for the transferrin gene, as judged by hybridization with β-actin cDNA. The accmulation of transferrin mRNA induced by OE2 treatment was similar to the developmentally regulated expression of the gene observed during the reproductive cycle. The steady-state level of mammary transferrin m…