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The last 10 years of knowledge on near infrared (NIR) applications in the horticultural field are summarized. NIR spectroscopy is considered one of the most suitable technologies of investigation worldwide used as a nondestructive approach to monitoring raw materials and products in several fields. There are different types of approaches that can be employed for the study of key issues for horticultural products. In this paper, an update of the information collected from the main specific International Journals and Symposia was reported. Many papers showed the use of NIR spectroscopy in the horticultural field, and the literature data were grouped per year, per product, and per application, such as studies of direct (chemical composition) and indirect (physical and sensorial) properties (P), process control (PC), and authenticity and classification studies (AC). A mention was made of a recent innovative approach that considers the contribution of water absorption in the study of biological systems.

The affinity of aflatoxin M1 toward the main milk protein fractions in ewe and goat milk was investigated by using an ELISA. This study took into account the possible effects of common dairy processes such as ultrafiltration, acidic or rennet curding, and production of ricotta from acidic or rennet whey. Treatments that allowed the separation of casein from whey proteins under conditions that do not alter the physical or chemical status of the proteins (such as ultracentrifugation) were used as a reference. None of the treatments used in typical dairy processes caused significant release of the toxin, in spite of the relevant changes they induced in the interactions among proteins. Only the combined heat and acidic treatment used for production of ricotta cheese altered the structure of whey proteins to the point where they lost their ability to bind the toxin. This study also showed that, regardless of the physical state of the sample, a commercial electronic nose device, in combination with appropriate statistical tools, was able to discriminate among different levels of sample contamination.

The presence of milk fat globule emulsion produces scattering phenomena on near infrared (NIR) radiation through the raw milk. Numerically, 80% of milk fat globules have a diameter of less than 3 µm interfering with the radiation having a wavelength from 1 µm to 2.5 µm with a radiation dispersion in all directions. Consequently, the NIR transmitted radiation does not behave in accordance with Lambert-Beer's law: the NIR spectra of milk samples with high fat content have high offset values and lower specific absorptions than those of samples with lower fat levels. Usually, this problem is reduced by acting at the level of sample preparation (homogenisation), of optical geometry (transflectance mode coupled with the use of an integrating sphere to collect the widespread radiation) and using chemometric regression models able to optimise non-linear spectral responses. Transmittance measurements have already been exploited for the determination of macro-composition in the agro-food and in the dairy fields. In this work, a set of 150 individual milk samples, collected over three days from a single farm with 49 milking cows, was analysed with Fourier transform-NIR apparatus in order to study the effects of scattering on partial least squares predictors for casein. The spectra of non-homogenised raw whole milk and the respective skimmed samples were collected in transmission mode. Using the true scattering curves obtained by subtraction from the raw milk spectra of skimmed milk spectra the extended multiplicative scatter correction (EMSC) estimate of scattering effects was optimised. EMSC uses polynomial filters in modelling the aspecific absorptions due to the scattering effects. The correct scatter elimination can help in the individuation and interpretation of the true predictors in calibration procedures.