Development of a New Measurement Unit (MilkSpec-1) for Rapid Determination of Fat, Lactose, and Protein in Raw Milk Using Near-Infrared Transmittance Spectroscopy

Abstract

A new measurement unit, the MilkSpec-1, has been developed to determine rapidly and nondestructively the content of fat, lactose, and protein in raw milk using near-infrared transmittance spectroscopy. The spectral range over 700 to 1100 nm was used. This unit was designed for general glass test tubes, 12 mm in diameter and 10 mL in volume. Al2O3 with a thickness of 2.5 mm was found to be optimum as a reference for acquiring the milk spectrum for this measurement. The NIR transmittance spectra of milk were acquired from raw milk samples without homogenization. The calibration model was developed and predicted by using a partial least-squares (PLS) algorithm. In order to reduce the scattering effect due to fat globules and casein micelles in NIR transmittance spectra, multiplicative scatter correction (MSC) and/or second derivative treatment were performed. MSC treatment proved to be useful for the development of calibration models for fat and protein. This study resulted in low standard errors of prediction (SEP), with 0.06, 0.10, and 0.10% for fat, lactose, and protein, respectively. It is shown that accurate, rapid, and nondestructive determination of milk composition could be successfully performed by using the MilkSpec-1, presenting the potential use of this method for real-time on-line monitoring in a milking process.

Portable milk product quality analyzer based on spectrometry in the near IR range

“…4, we see that regression on lactose content is pronounced (correlation coefficient R 2 = 80.44%). The RMSCV for lactose is acceptably small, and corresponds to the results of [10] obtained with laboratory NIR spectrometers. Increasing the number of "training" samples did not led to an appreciable decrease in the error, but simplified the model (optimal number of factors: 3).…”

Predicting sensory score of cod (Gadus morhua) from visible spectroscopy

“…NIR analysis of meat includes applications such as determination of fat content of minced meat (Togersen, Isaksson, Nilsen, Bakker, & Hildrum, 1999), and differentiating between frozen and unfrozen beef (Thyholt & Isaksson, 1997). The method is also used for analysis of dairy products (Woo et al, 2002) and wheat and wheat products (Miralbes, 2003). Recent reviews of the method and its applications are given in Pasquini (2003) and Blanco and Villarroya (2002).…”

NMR spectroscopy as a screening tool to validate nutrition labeling of milk, lactose-free milk, and milk substitutes based on soy and grains

“…The most frequently used technique for lactose determination in milk and dairy products is an enzymatic assay based on spectrophotometric measurement, which is also the German reference method (Amtliche Sammlung von Untersuchungsverfahren 2010). Other approaches include biosensors (Ammam and Fransaer 2010), colorimetry (Bakos et al 2002), near-infrared (NIR) spectroscopy (Kawasaki et al 2008;Woo et al 2002), Fourier transform infrared spectroscopy (Lefier et al 1996), or chromatographic techniques (Eadala et al 2009;Paredes et al 2006;Schuster-Wolff-Bühring et al 2011). Besides being comparably time-consuming, none of these methods appear to be appropriate for our purpose to provide a rapid screening of nutrition parameters.…”