Determination of water droplet size distribution in butter: Pulsed field gradient NMR in comparison with confocal scanning laser microscopy

lent, Katrien Van; Vanlerberghe, Brecht; Oostveldt, Patrick Van; Thas, Olivier; Meeren, Paul Van der

doi:10.1016/j.idairyj.2007.07.002

Cited by 39 publications

(14 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…According to the literature, the diameters of water droplets in the two churned butter samples and commercial butter are found in the following ranges: 10-30 μm for ChB1, 5-8 μm for ChB2 and 2-4 μm for CB82 (Van Lent et al 2008;Voysey et al 2009b). …”

Section: Fig 3 Evolution Of Bacterial Parameters and Ph During A Chmentioning

confidence: 99%

Growth Potential Assessment of Listeria in Milk Fat Products by Challenge Testing

Michelon

Leclercq

Garric

et al. 2015

Journal of Food Safety

View full text Add to dashboard Cite

Milk fat products (MFP), including butter and low-fat dairy spreads, are a specific type of ready-to-eat food known as water-in-fat emulsions, in which the behavior of microbial foodborne pathogens such as Listeria monocytogenes is not clearly known. This study investigated the growth and survival of L. monocytogenes, and of Listeria innocua as a surrogate for L. monocytogenes, in these foods using challenge testing. Three commercial MFPs with various fat contents (butter, half butter and low-fat dairy spread) and two samples of traditional churned butter with various water droplet sizes were artificially contaminated with Listeria. Total mesophilic microflora including lactic acid bacteria, pH and Listeria were monitored throughout the shelf life. The growth potential of Listeria was calculated in the course of the shelf life and remains below the limit value of 0.5 log cfu/g during the whole shelf life in any of the butter. However, the concentration of Listeria remained stable during the shelf life in the tested MFPs (commercial and churned) except in the commercial low-fat dairy spread in which Listeria decreased gradually. PRACTICAL APPLICATIONSEuropean Union regulation No. 2073/2005 lays down the microbiological limit criteria for Listeria monocytogenes in ready-to-eat foods (RTE). According to this regulation, each RTE food has to be classified, with scientific justification, as able or unable to support the growth of L. monocytogenes during the shelf life. This challenge-test study on milk fat products (MFPs) provided some useful data needed to assess the behavior of Listeria in these particular RTE food products. This study showed that while MFPs do not promote growth, they do support Listeria survival. Water droplet size seems to be a key parameter in preventing the growth of both microflora and Listeria. The study also showed that, in order to determine whether a given MFP supports Listeria growth or not, it is crucial to investigate the impact of the variations in physico-chemical and microbiological parameters of each butter-making process used by companies.

show abstract

Section: Fig 3 Evolution Of Bacterial Parameters and Ph During A Chmentioning

confidence: 99%

Growth Potential Assessment of Listeria in Milk Fat Products by Challenge Testing

Michelon

Leclercq

Garric

et al. 2015

Journal of Food Safety

View full text Add to dashboard Cite

show abstract

“…A routine PFG-NMR method has been proposed for the measurement of droplet size distribution in water/oil or oil/water emulsions [88][89][90]. The accuracy of the method has been widely debated for water droplet and oil droplet size determination in food emulsions such as butter, margarine and dressings [91][92][93][94]. Some extension of the method has recently been proposed for spatial determination of droplet size distribution from MRI data in emulsions [95] and to provide both real-time dispersion and spatially-resolved velocity measurements in a frozen drop of sucrose solution and emulsion [96].…”

Section: Diffusionmentioning

confidence: 99%

Investigations of food colloids by NMR and MRI

Mariette¹

2009

Current Opinion in Colloid & Interface Science

118

View full text Add to dashboard Cite

Since the publication of the ISO method for measurement of solid fat content using NMR relaxation at low field, the application of this technique to the characterisation of food composition and food structure on several length scales has expanded considerably.Improvements in the electronic and computational specifications of NMR spectrometers and the use of more sophisticated signal processing methods have led to several new applications, and NMR, previously recognized as a powerful technique to provide information regarding composition, is now widely used for microstructural investigations. Moreover, MRI applications have in recent years been extended from the medical field to food science and this has opened up new opportunities for the understanding of food. We examine here recent developments in these techniques, including NMR relaxation, multidimensional NMR relaxation, diffusion NMR and MRI.

show abstract

“…Butter is water-in-oil emulsions consisting of crystallized fat in a continuous phase, in which water droplets (2.3-10.6 μm) [31,32], milk fat globules (2.5 μm) [33], and partially damaged fat globules are dispersed. It contains 80% of fat, which is partly crystallized.…”

Section: Resultsmentioning

confidence: 99%