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1.
J Dairy Sci ; 102(9): 7640-7654, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31255272

RESUMEN

Automatic milking systems (AMS), first introduced on dairy farms in the 1990s, rapidly spread across many countries. This technology is based on the voluntary milking of dairy cattle in a completely automated process, which relies on computer management, with a substantial average increase in milking frequency. Compared with conventional milking, AMS significantly alters herd management, with important implications on economic, technical, and social aspects of farming, on animal physiology, health, and well-being. These aspects are explored in an extensive body of research. In contrast, the effects of AMS adoption on milk quality are often overlooked. This review draws together both positive and negative effects of AMS on the milk production chain, particularly emphasizing the variations of hygienic and compositive characteristics of raw milk and their interplay, as compared with milk obtained with conventional milking. Scattered and sometimes conflicting literature exists on whether and how these variations may influence quality and yield of the derived dairy products. Current scientific knowledge on these crucial aspects is thus reviewed, with particular focus on milk technological suitability for being processed into dairy products having the target characteristics in terms of taste, structure, on-storage stability, and sustainability. Provided the managing conditions are optimized, AMS allow increased milk production, mostly due to more frequent milking, without compromising the milk characteristics that are crucial to food industry for processing. Nevertheless, specific biochemical aspects related to the changed milking interval, which determines the duration of enzyme activities and bacterial growth in milk, need further research.


Asunto(s)
Bovinos/fisiología , Industria Lechera/métodos , Higiene , Leche/química , Robótica/métodos , Animales , Productos Lácteos/análisis , Industria Lechera/instrumentación , Femenino , Calidad de los Alimentos , Lactancia , Leche/microbiología , Tecnología
2.
Food Microbiol ; 57: 16-22, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27052697

RESUMEN

Lysozyme (LZ) is used in several cheese varieties to prevent late blowing which results from fermentation of lactate by Clostridium tyrobutyricum. Side effects of LZ on lactic acid bacteria population and free amino acid pattern were studied in 16 raw-milk hard cheeses produced in eight parallel cheese makings conducted at four different dairies using the same milk with (LZ+) or without (LZ-) addition of LZ. The LZ-cheeses were characterized by higher numbers of cultivable microbial population and lower amount of DNA arising from lysed bacterial cells with respect to LZ + cheeses. At both 9 and 16 months of ripening, Lactobacillus delbrueckii and Lactobacillus fermentum proved to be the species mostly affected by LZ. The total content of free amino acids indicated the proteolysis extent to be characteristic of the dairy, regardless to the presence of LZ. In contrast, the relative patterns showed the microbial degradation of arginine to be promoted in LZ + cheeses. The data demonstrated that the arginine-deiminase pathway was only partially adopted since citrulline represented the main product and only trace levels of ornithine were found. Differences in arginine degradation were considered for starter and non-starter lactic acid bacteria, at different cheese ripening stages.


Asunto(s)
Arginina/metabolismo , Queso/microbiología , Aditivos Alimentarios/farmacología , Lactobacillus/metabolismo , Muramidasa/farmacología , Animales , Arginina/análisis , Bovinos , Queso/análisis , Fermentación , Manipulación de Alimentos , Lactobacillus/efectos de los fármacos , Leche/microbiología
3.
J Dairy Sci ; 99(8): 6144-6156, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27236764

RESUMEN

Chemical composition and structure of different types of macroparticles (specks, spots) and microparticles (microcrystals) present in hard and extra-hard cheeses were investigated. Light microscopy revealed that the small hard specks had the structure of crystalline tyrosine, as confirmed by amino acid analysis. Spots showed a complex structure, including several curd granules, cavities, and microcrystals, and were delimited by a dense protein layer. Spots contained less moisture and ash than the adjacent cheese area, and more protein, including significantly higher contents of valine, methionine, isoleucine, leucine, tyrosine, and phenylalanine. Microcrystals were observed by light and electron microscopy and analyzed by confocal micro-Raman. Among others, calcium phosphate crystals appeared to consist of a central star-shaped structure immersed in a matrix of free fatty acids plus leucine and phenylalanine in free form or in small peptides. A hypothetical mechanism for the formation of these structures has been formulated.


Asunto(s)
Queso/análisis , Proteínas de la Leche/química , Aminoácidos/análisis , Aminoácidos/química , Animales , Fosfatos de Calcio/química , Cristalización , Ácidos Grasos no Esterificados/análisis , Manipulación de Alimentos , Microscopía Confocal , Microscopía Electrónica
4.
Artículo en Inglés | MEDLINE | ID: mdl-38631976

RESUMEN

AIMS: There is increasing interest in the opportunities offered by Real World Data (RWD) to provide evidence where clinical trial data does not exist, but access to appropriate data sources is frequently cited as a barrier to RWD research. This paper discusses current RWD resources and how they can be accessed for cancer research. MATERIALS AND METHODS: There has been significant progress on facilitating RWD access in the last few years across a range of scales, from local hospital research databases, through regional care records and national repositories, to the impact of federated learning approaches on internationally collaborative studies. We use a series of case studies, principally from the UK, to illustrate how RWD can be accessed for research and healthcare improvement at each of these scales. RESULTS: For each example we discuss infrastructure and governance requirements with the aim of encouraging further work in this space that will help to fill evidence gaps in oncology. CONCLUSION: There are challenges, but real-world data research across a range of scales is already a reality. Taking advantage of the current generation of data sources requires researchers to carefully define their research question and the scale at which it would be best addressed.

5.
JPRAS Open ; 33: 92-105, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35812357

RESUMEN

Introduction: Acellular dermal matrices (ADM) have been suggested to allow for different approaches and reduce the risk of postoperative complications in implant-based breast surgery. Surgeons seem to embrace ADMs around the world, although a lack of consistent evidence regarding the factors that increase the risk of major postoperative complications remains. Purpose: To develop and internally validate a model to predict the risk of a major postoperative complication in breast reconstructive surgery with and without an ADM. Methodology: The DBIR is an opt-out registry that holds characteristics of all breast implant surgeries in the Netherlands since 2015. Using a literature-driven preselection of predictors, multivariable mixed-effects logistic regression modelling was used to develop the prediction model. Results: A total of 2939 breasts were eligible, of which 11% underwent an ADM-assisted procedure (single-stage or two-stage). However, 31% underwent a two-stage procedure (with or without the use of ADM). Of all breasts, 10.2% developed a major postoperative complication. Age (OR 1.01), delayed timing (OR 0.71), and two-stage technique (OR 4.46) were associated with the outcome. Conclusion: The data suggest that ADM use was not associated with a major postoperative complication, while two-stage reconstructions were strongly associated with an increased risk of major complications. Despite these findings, ADMs are not as popular in the Netherlands as in the USA. The predictive capabilities of the developed model are mediocre to poor, but because of the above findings, we believe that the role of the two-stage technique as a golden standard should be put up for debate.

6.
Food Res Int ; 107: 477-485, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29580509

RESUMEN

Fat separation, gelation or sedimentation of UHT milk during shelf-storage represent instability phenomena causing the product rejection by consumers. Stability of UHT milk is of increasing concern because access to emerging markets currently implies for this product to be stable during shipping and prolonged storage, up to 12 months. The role of microfiltration prior to UHT process in avoiding or retarding the gelation or sediment formation was studied by comparing microfiltered UHT milk to conventional UHT milk. A second trial was set up to study the effects of double ultra-high pressure homogenization in delaying the cream rising and UHT milk homogenized once at lower pressure was taken as control. All milk samples were produced at industrial plant level. Milk packages were stored at 22 °C, opened monthly for visually inspecting the presence of cream layer, gel or sediment and then analysed. Microfiltration markedly delayed the formation of both gel particles and sediment, with respect to the control, and slowed down the proteolysis in terms of accumulation of peptides although no correlation was observed between the two phenomena. The double homogenization, also evaluated at ultra-structural level, narrowed the fat globule distribution and the second one (400 MPa), performed downstream to the sterilization step, disrupted the fat-protein aggregates produced in the first one (250 MPa). The adopted conditions avoided the appearance of the cream layer in the UHT milk up to 18 months. This study contributes important knowledge for developing strategies to delay instability phenomena in UHT milk destined to extremely long shelf storage.


Asunto(s)
Filtración/métodos , Conservación de Alimentos/métodos , Calor , Leche , Animales , Filtros Microporos , Microscopía Confocal , Microscopía Electrónica de Transmisión , Presión , Tiempo
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