Author:

Keywords:

Science & Technology, Life Sciences & Biomedicine, Physical Sciences, Technology, Biophysics, Chemistry, Physical, Materials Science, Biomaterials, Chemistry, Materials Science, Food emulsion, Milk, Ultrasonic homogenization, Vis/NIR spectroscopy, Light scattering, Fat globule size distribution, FAT GLOBULE SIZE, HIGH-PRESSURE HOMOGENIZATION, DYNAMIC LIGHT-SCATTERING, RAW BOVINE-MILK, CASEIN MICELLES, ACID-COMPOSITION, INTRALIPID(R) PHANTOMS, SPECTROSCOPIC ANALYSIS, DEPENDENT SCATTERING, MULTIPLE-SCATTERING, Animals, Lasers, Optical Phenomena, Particle Size, Spectrophotometry, Ultraviolet, Spectroscopy, Near-Infrared, Surface Properties, Ultrasonics, 0306 Physical Chemistry (incl. Structural), 0903 Biomedical Engineering, 0904 Chemical Engineering, Chemical Physics, 3406 Physical chemistry, 4003 Biomedical engineering, 4004 Chemical engineering

Abstract:

The size of colloidal particles in food products has a considerable impact on the product's physicochemical, functional and sensory characteristics. Measurement techniques to monitor the size of suspended particles could, therefore, help to further reduce the variability in production processes and promote the development of new food products with improved properties. Visible and near-infrared (Vis/NIR) spectroscopy is already widely used to measure the composition of agricultural and food products. However, this technology can also be consulted to acquire microstructure-related scattering properties of food products. In this study, the effect of the fat globule size on the Vis/NIR bulk scattering properties of milk was investigated. Variability in fat globule size distribution was created using ultrasonic homogenization of raw milk. Reduction of the fat globule size resulted in a higher wavelength-dependency of both the Vis/NIR bulk scattering coefficient and the scattering anisotropy factor. Moreover, the anisotropy factor and the bulk scattering coefficients for wavelengths above 600 nm were reduced and were dominated by Rayleigh scattering. Additionally, the bulk scattering properties could be well (R(2) ≥ 0.990) estimated from measured particle size distributions by consulting an algorithm based on the Mie solution. Future research could aim at the inversion of this model to estimate the particle size distributions from Vis/NIR spectroscopic measurements.