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1.
J Dairy Sci ; 2024 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-38908705

RESUMEN

The production of whey protein concentrates (WPCs) from camel milk whey represents an effective approach to valorize this processing by-product. These concentrates harbor active ingredients with significant bioactive properties. Camel WPCs were spray-dried (SD) at inlet temperature of 170, 185 and 200°C, or Ultrasonicated (US) for 5, 10 and 15 min, then freeze-dried to obtain fine powder. The impact of both treatments on protein degradation was studied by sodium dodecyl sulfate-PAGE and reverse-phase ultraperformance liquid chromatography (RP-UPLC) techniques. Significantly enhanced protein degradation was observed after US treatment when compared with SD. Both SD and US treatments slightly enhanced the WPCs samples' antioxidant activities. The US exposure for 15 min exhibited highest 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) scavenging activity (12.12 mmol TE/g). Moreover, US treatment for 10 min exhibited the highest in vitro anti-diabetic properties (α-amylase and α-glucosidase inhibition), and dipeptidyl-peptidase-IV inhibitory activity among all samples. In addition, the ultrasonication for 10 min and SD at 170°C showed the lowest IC50 values for in vitro anti-hypercholesterolemic activities in terms of pancreatic lipase and cholesteryl esterase inhibition. Conclusively, these green techniques can be adapted in the preservation and processing of camel milk whey into active ingredients with high bioactive properties.

2.
J Sci Food Agric ; 104(3): 1470-1478, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37804504

RESUMEN

BACKGROUND: A foam layer makes an essential contribution to the quality of cappuccino-style drinks. Poor foaming of milk occurs quite often, however, especially in summer. The reasons for this are still unknown. Although a substantial number of studies on the foaming process of milk have been reported, these studies have been laboratory based and have used laboratory or pilot-scale equipment to simulate the processing conditions of a dairy processing factory. This study collected about 40 different samples across different processing stages in a dairy factory over two seasons (two batches per season) and investigated their composition and physical and foaming properties by mechanical mixing and steam injection. RESULTS: The results showed that milk samples collected in summer had a significantly higher content of fat, free fatty acids, and Ca2+ ions, and larger particle sizes but a markedly lower concentration of protein and solid non-fat, and surface tension than the samples collected in spring. These differences provided spring milk with a higher steam injection foamability than summer milk. However, steam injection foam stability, and mechanical mixing foamability and foam stability were not affected by seasonal factors. Milk samples collected in different batches within a season were almost identical with regard to the properties that were investigated. CONCLUSION: The variations in composition and physical properties of milk collected between two seasons could be the reasons for their difference in foamability but not for foam stability. Processes such as standardization, homogenization, and pasteurization improved markedly the foaming properties of milk. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Asunto(s)
Leche , Vapor , Animales , Leche/química , Estaciones del Año , Pasteurización
3.
Curr Atheroscler Rep ; 25(8): 495-507, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37523052

RESUMEN

PURPOSE OF REVIEW: The goal of this article is to review algorithms for treating dyslipidemia in youth, discuss pitfalls, propose enhanced algorithms to address pitfalls, and consider future directions. RECENT FINDINGS: The presence of modifiable and non-modifiable cardiovascular disease (CVD) risk factors during childhood is associated with CVD-related events in adulthood. Recent data has shown that childhood initiation of statin therapy in youth < 18 years of age with familial hypercholesterolemia reduces the risk of adult CVD. However, pediatric dyslipidemia remains undertreated in part due to a lack of primary health care providers with adequate understanding of screening guidelines and pediatric lipidologists with experience in treatment and follow-up of this unique population. Management algorithms have been published by the National Heart, Lung, and Blood Institute and American Heart Association as tools to empower clinicians to manage dyslipidemia. We propose enhanced algorithms, which incorporate recently approved pharmacotherapy to address the management gaps. Future algorithms based upon clinical risk scores may enhance treatment and improve outcomes. Algorithms for dyslipidemia management which target youth < 18 years of age are tools which empower clinicians to manage dyslipidemia in this unique population. Enhanced algorithms may help address pitfalls. We acknowledge the need for further risk assessment tools in pediatrics for tailored dyslipidemia management.


Asunto(s)
Enfermedades Cardiovasculares , Dislipidemias , Hiperlipoproteinemia Tipo II , Adulto , Estados Unidos , Humanos , Niño , Adolescente , Dislipidemias/diagnóstico , Dislipidemias/tratamiento farmacológico , Dislipidemias/epidemiología , Factores de Riesgo , Medición de Riesgo , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/prevención & control
4.
J Sci Food Agric ; 103(11): 5312-5321, 2023 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-37016733

RESUMEN

BACKGROUND: The attraction of cappuccino-style beverages is attributed to the foam layer, as it greatly improves the texture, appearance, and taste of these products. Typical milk has a low concentration of free fatty acids (FFAs), but their concentration can increase due to lipolysis during processing and storage, which is detrimental to the foamability and foam stability of milk. There are contradictory results in reported studies concerning the effects of FFAs on the foaming properties of milk due to differences in milk sources, methods inducing lipolysis, and methods of creating foam. In this study, the foaming properties and foam structure of milk samples whose lipolysis was induced by ultra-turraxing, homogenisation, and microfluidisation (1.5-3.5 µ-equiv. mL-1 FFAs) were investigated. RESULTS: Compared with others, microfluidised milk samples had the smallest particle size, lowest absolute zeta potential, and highest surface tension; thus exhibited high foamability and foam stability, and very small and homogeneous air bubbles in foam structure. For all shearing methods, increasing FFA content from 1.5 to 3.5 µ-equiv. mL-1 markedly decreased the surface tension, foamability, and foam stability of milk samples. The FFA level that led to undesirable foam structure was 1.5 µ-equiv. mL-1 for ultra-turraxed milk samples and 2.5 µ-equiv. mL-1 for homogenised and microfluidised ones. CONCLUSION: Shearing-induced lipolysis greatly affected the physical properties of milk samples and subsequently their foaming properties and foam structure. At the same FFA level, lipolysis induced by microfluidisation was much less detrimental to the foaming properties of milk than lipolysis induced by ultra-turraxing and homogenisation. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.


Asunto(s)
Lipólisis , Leche , Animales , Leche/química , Ácidos Grasos no Esterificados/análisis , Tamaño de la Partícula
5.
Crit Rev Food Sci Nutr ; 62(17): 4800-4820, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-33527840

RESUMEN

For many dairy products such as cappuccino-style beverages, the top foam layer determines the overall product quality (e.g. their appearance, texture, mouthfeel and coffee aroma release rate) and the consumer acceptance. Proteins in milk are excellent foaming agents, but the foaming properties of milk are greatly affected by several factors such as the protein content, ratio of caseins to whey proteins, casein micelle size, pH, minerals, proteolysis, presence of low molecular weight compounds (lipids and their hydrolyzed products) and high molecular weight compounds (polysaccharides); milk processing conditions (e.g. homogenization, heat treatment and aging); and foaming method and temperature. These factors either induce changes in the molecular structure, charge and surface activity of the milk proteins; or interfere and/or compete with milk proteins in the formation of highly viscoelastic film to stabilize the foam. Some factors affect the foamability while others determine the foam stability. In this review, functionality of milk proteins in the production and stabilization of liquid foam, under effects of these factors is comprehensively discussed. This will help to control the foaming process of milk on demand for a particular application, which still is difficult and challenging for researchers and the dairy industry.


Asunto(s)
Proteínas de la Leche , Leche , Animales , Caseínas/análisis , Caseínas/química , Micelas , Leche/química , Proteínas de la Leche/química , Proteína de Suero de Leche/química
6.
PLoS Genet ; 14(8): e1007574, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-30074984

RESUMEN

The broadly conserved bacterial signalling molecule cyclic-di-adenosine monophosphate (c-di-AMP) controls osmoresistance via its regulation of potassium (K+) and compatible solute uptake. High levels of c-di-AMP resulting from inactivation of c-di-AMP phosphodiesterase activity leads to poor growth of bacteria under high osmotic conditions. To better understand how bacteria can adjust in response to excessive c-di-AMP levels and to identify signals that feed into the c-di-AMP network, we characterised genes identified in a screen for osmoresistant suppressor mutants of the high c-di-AMP Lactococcus ΔgdpP strain. Mutations were identified which increased the uptake of osmoprotectants, including gain-of-function mutations in a Kup family K+ importer (KupB) and inactivation of the glycine betaine transporter transcriptional repressor BusR. The KupB mutations increased the intracellular K+ level while BusR inactivation increased the glycine betaine level. In addition, BusR was found to directly bind c-di-AMP and repress expression of the glycine betaine transporter in response to elevated c-di-AMP. Interestingly, overactive KupB activity or loss of BusR triggered c-di-AMP accumulation, suggesting turgor pressure changes act as a signal for this second messenger. In another group of suppressors, overexpression of an operon encoding an EmrB family multidrug resistance protein allowed cells to lower their intracellular level of c-di-AMP through active export. Lastly evidence is provided that c-di-AMP levels in several bacteria are rapidly responsive to environmental osmolarity changes. Taken together, this work provides evidence for a model in which high c-di-AMP containing cells are dehydrated due to lower K+ and compatible solute levels and that this osmoregulation system is able to sense and respond to cellular water stress.


Asunto(s)
Proteínas Bacterianas/fisiología , Betaína/metabolismo , AMP Cíclico/metabolismo , Lactococcus lactis/fisiología , Osmorregulación , Potasio/metabolismo , Adenosina Monofosfato , Proteínas Bacterianas/genética , Regulación Bacteriana de la Expresión Génica , Lactococcus lactis/genética , Mutación , Operón , Concentración Osmolar , Sistemas de Mensajero Secundario
7.
J Dairy Sci ; 104(2): 1304-1317, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33272578

RESUMEN

This study investigated the effect of camel milk protein hydrolysates (CMPH) at 100, 500 and 1,000 mg/kg of body weight (BW) for 8 wk on hyperglycemia, hyperlipidemia, and associated oxidative stress in streptozotocin-induced diabetic rats. Body weights and fasting blood glucose levels were observed after every week until 8 wk, and oral glucose tolerance test (OGTT) levels and biochemical parameters were evaluated after 8 wk in blood and serum samples. Antioxidant enzyme activity and lipid peroxidation in the liver were estimated, and histological examination of the liver and pancreatic tissues was also conducted. Results showed that CMPH at 500 mg/kg of BW [camel milk protein hydrolysate, mid-level dosage (CMPH-M)] exhibited potent hypoglycemic activity, as shown in the reduction in fasting blood glucose and OGTT levels. The hypolipidemic effect of CMPH was indicated by normalization of serum lipid levels. Significant improvement in activity of superoxide dismutase and catalase, and reduced glutathione levels were observed, along with the attenuation of malondialdehyde content in groups fed CMPH, especially CMPH-M, was observed. Decreased levels of liver function enzymes (aspartate aminotransferase and alanine aminotransferase) in the CMPH-M group was also noted. Histology of liver and pancreatic tissue displayed absence of lipid accumulation in hepatocytes and preservation of ß-cells in the CMPH-M group compared with the diabetic control group. This is the first study to report anti-hyperglycemic and anti-hyperlipidemic effect of CMPH in an animal model system. This study indicates that CMPH can be suggested for its therapeutic benefits for hyperglycemia and hyperlipidemia, thus validating its use for better management of diabetes and associated comorbidities.


Asunto(s)
Camelus/metabolismo , Diabetes Mellitus Experimental/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Hipolipemiantes/uso terapéutico , Proteínas de la Leche/uso terapéutico , Estrés Oxidativo/efectos de los fármacos , Animales , Antioxidantes/uso terapéutico , Glucemia/análisis , Diabetes Mellitus Experimental/sangre , Diabetes Mellitus Experimental/patología , Células Secretoras de Insulina/patología , Peroxidación de Lípido/efectos de los fármacos , Hígado/química , Hígado/patología , Masculino , Malondialdehído/metabolismo , Leche/metabolismo , Hidrolisados de Proteína/uso terapéutico , Ratas
8.
J Paediatr Child Health ; 56(12): 1872-1874, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32767639

RESUMEN

AIM: As the COVID-19 pandemic evolves, human milk banks world-wide continue to provide donor human milk to vulnerable infants who lack access to mother's own milk. Under these circumstances, ensuring the safety of donor human milk is paramount, as the risk of vertical transmission of SARS-CoV-2 is not fully understood. Here, we investigate the inactivation of SARS-CoV-2 in human milk by pasteurisation and the stability of SARS-CoV-2 in human milk under cold storage. METHODS: SARS-CoV-2 was experimentally inoculated into human milk samples from healthy donors or into a control medium. Triplicates of each sample were layered onto uninfected cells after Holder pasteurisation (63°C for 30 min), heating to 56°C for 30 min, or after 48 h of storage at 4°C or -30°C. Infectious titres of virus were determined at 72 h post-infection by endpoint titration. RESULTS: Following heating to 63°C or 56°C for 30 min, replication competent (i.e. live) SARS-CoV-2 was undetected in both human milk and the control medium. Cold storage of SARS-CoV-2 in human milk (either at 4°C or -30°C) did not significantly impact infectious viral load over a 48 h period. CONCLUSION: SARS-CoV-2 is effectively inactivated by Holder pasteurisation, suggesting that existing milk bank processes will effectively mitigate the risk of transmission of SARS-COV-2 to vulnerable infants through pasteurised donor human milk. The demonstrated stability of SARS-CoV-2 in refrigerated or frozen human milk may assist in the development of guidelines around safe expressing and storing of milk from COVID-19 infected mothers.


Asunto(s)
COVID-19 , Frío , Leche Humana/virología , Pasteurización , SARS-CoV-2 , Inactivación de Virus , Humanos
9.
J Neurosci Res ; 97(4): 377-390, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30506706

RESUMEN

Progress in basic and clinical research is slowed when researchers fail to provide a complete and accurate report of how a study was designed, executed, and the results analyzed. Publishing rigorous scientific research involves a full description of the methods, materials, procedures, and outcomes. Investigators may fail to provide a complete description of how their study was designed and executed because they may not know how to accurately report the information or the mechanisms are not in place to facilitate transparent reporting. Here, we provide an overview of how authors can write manuscripts in a transparent and thorough manner. We introduce a set of reporting criteria that can be used for publishing, including recommendations on reporting the experimental design and statistical approaches. We also discuss how to accurately visualize the results and provide recommendations for peer reviewers to enhance rigor and transparency. Incorporating transparency practices into research manuscripts will significantly improve the reproducibility of the results by independent laboratories.


Asunto(s)
Investigación Biomédica/normas , Edición/normas , Exactitud de los Datos , Humanos , Mejoramiento de la Calidad , Reproducibilidad de los Resultados , Proyectos de Investigación/normas
10.
Crit Rev Food Sci Nutr ; 58(15): 2557-2569, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-28609184

RESUMEN

Use of gases (air, carbon dioxide and nitrogen) has been practiced in the manufacture of dairy products (i.e., ice cream, whipped cream and butter) to improve their texture, mouthfeel and shelf-life extension. Many attempts have also been made to incorporate other gases such as hydrogen, nitrous oxide, argon, xenon, and helium into the dairy systems for various product functionalities such as whipping, foaming, texture, aroma enhancement, and therapeutic properties. The gases can be dissolved in aqueous and fat phases or remain in the form of bubbles stabilized by protein or fat particles. The gas addition or infusion processes are typically simple and have been used commercially. This review focuses on the use of various gases in relation to their individually physical properties along with their specific roles in manufacturing and controlling quality of dairy products. It also recaps on how gases are included in the dairy systems. The information is important in understanding of addition of specific gas(es) into food systems, particularly dairy products, that potentially provide intervention opportunities for modifying and/or creating innovative food structures and functionalities.


Asunto(s)
Productos Lácteos , Tecnología de Alimentos , Gases/química , Aire , Animales , Dióxido de Carbono , Nitrógeno , Óxido Nitroso
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