NIRS to assess chemical composition of sheep and goat cheese

Silvia Parrini, Alessandro Crovetti, Chiara Aquilani, Lapo Nannucci, Riccardo Bozzi


Submitted 2020-07-01 | Accepted 2020-09-02 | Available 2020-12-01

The present study aimed to evaluate the performances of Fourier transform near-infrared spectroscopy technique to determine the chemical and the fatty acid composition of different types of cheeses. A total of 95 cheeses from sheep and goat raw milk were produced in small local dairies of Siena province (Tuscany). For each cheese, spectrum was collected in intact slices of the sample and fatty acid profile was determined in ground samples. Outliers were identified and different mathematical pre-processing treatments (SNV, MSC, baseline correction and de-trending) were applied when necessary. Considering traditional chemical analysis and raw cheese spectral data, calibration and cross-validation models were carried out using partial least squares regression (PLS). The best results were evaluated in terms of coefficient of determination in calibration and cross-validation (R2cv), and root mean square error in calibration and cross-validation, and residual prediction deviation (RPD). Moisture, protein and ash showed the best R2cv (0.89, 0.74 and 0.72, respectively) and RPD values (3.0, 2.6 and 2.1, respectively). Saturated, monounsaturated and polyunsaturated fatty acids showed R2cv which ranged from 0.75 to 0.67, and RPD <2.0. Intermediate results in terms of R2cv (0.62 as mean) were obtained for medium chain saturated fatty acids (C8:0 to C14:0), whereas for C18 series only oleic acid reached good accuracy of prediction (R2cv >0.70). Obtained results are promising and additional samples could strongly increase the predictive ability for small dairy farms.

Keywords: FT-NIRS, cheese, fatty acid, quality


AOAC, 2019. Official Methods of Analysis. 21st ed., Association of Official Analytical Chemists, Washington, DC, USA.

Birth, G. and Hecht, H. (1987). The Physics of Near-Infrared Reflectance. Near Infrared Technology in the Agricultural and Food Industries. American Association of Cereal Chemists, Inc. St. Paul, Minnesota, USA.

Cuibus, L. et al. (2014). Preliminary discrimination of cheese adulteration by FT-IR spectroscopy. Bulletin UASVM Food Science and Technology, 71, 142-146.

De Marchi, M. et al. (2018). Invited review: Use of infrared technologies for the assessment of dairy products - Applications and perspectives. Journal of Dairy Science, 101, 10589–10604.

Esbensen, K. H. et al. (2014). The RPD myth... NIR news, 25(5), 24-28.

Faber, N. M. and Rajko, R. (2007). How to avoid over-fitting in multivariate calibration—The conventional validation approach and an alternative.Analytica Chimica Acta, 595(1-2), 98-106.

Folch, J., Lees, M. and Sloane Stanley, G. H. (1957). A simple method for the isolation and purification of total lipides from animal tissues. Journal of Biological Chemistry, 226, 497-509.

Fox, P. F. et al. (1993). Cheese: Chemistry, Physics and Microbiology. London: Chapman & Hall.

González-Martín, M. I. et al. (2017). Discrimination between cheeses made from cow’s, ewe’s and goat’s milk from unsaturated fatty acids and use of the canonical biplot method. Journal of Food Composition and Analysis, 56, 34-40.

González-Martín, M. I. et al. (2020). The determination of fatty acids in cheeses of variable composition (cow, ewe's, and goat) by means of near infrared spectroscopy. Microchemical Journal, 156, 104854.

Holroyd, S. E. (2013). Review: The use of near infrared spectroscopy on milk and milk products. Journal of Near Infrared Spectroscopy, 21 (5), 311-322.

Karoui, R. and Dufour, E. (2003). Dynamic testing rheology and fluorescence spectroscopy investigations of surface to centre differences in ripened soft cheeses. International Dairy Journal, 13, 973-985.

Karoui, R. et al. (2006). Chemical characterisation of European Emmental cheeses by near infrared spectroscopy using chemometric tools. International Dairy Journal, 16, 1211–1217.

Kraggerud, H. et al. (2014). Prediction of sensory quality of cheese during ripening from chemical and spectroscopy measurements. International Dairy Journal, 34, 6–18.

Lucas, A. et al. (2008a). Prediction of dry matter, fat, pH, vitamins, minerals, carotenoids, total antioxidant capacity, and color in fresh and freeze-dried cheeses by visible-near-infrared reflectance spectroscopy. Journal of Agricultural and Food Chemistry, 56, 6801–6808.

Lucas, A. et al. (2008b). Prediction of fatty acid composition of fresh and freeze-dried cheeses by visible–near-infrared reflectance spectroscopy. International Dairy Journal,18, 595–604.

Manuelian, C. L. et al. (2017). Prediction of minerals, fatty acid composition and cholesterol content of commercial cheeses by near infrared transmittance spectroscopy. International Dairy Journal, 71, 107-113.

Markiewicz-Kęszycka, M. et al. (2013). Fatty acid profile of milk - a review. Bulletin of the Veterinary Institute in Pulawy, 57, 135–139.

Mazerolles, G. et al. (2001). Infrared and fluorescence spectroscopy for monitoring protein structure and interaction changes during cheese ripening. Le Lait, 81, 509-527.

Morrison, W. R. and Smith, L. M. (1964). Preparation of fatty acid methyl esters and dimethylac-etals from lipids with boron fluorid methanol. Journal of Lipid Research, 5, 600–608.

Nudda, A. et al. (2005). Seasonal variation in conjugated linoleic acid and vaccenic acid in milk fat of sheep and its transfer to cheese and ricotta. Journal of Dairy Science, 88, 1311-1319.

Ozen, B. F. and Mauer, L. J. (2002). Detection of hazelnut oil adulteration using FT-IR spectroscopy. Journal of Agricultural and Food Chemistry, 50, 3898–3901.

Pierce, M. M. and Wehling, R. L. (1994). Comparison of sample handling and data treatment methods for determining moisture and fat in Cheddar cheese by near-infrared spectroscopy. Journal of Agricultural and Food Chemistry, 42, 2830-2835.

Pollard, A. et al. (2003). Textural changes of natural Cheddar cheese during the maturation process. Journal of Food Science, 68, 2011-2016.

Rodriguez-Otero, J. L., Hermida, M. and Cepeda, A. (1995). Determination of fat, protein, and total solids in cheese by near-infrared reflectance spectroscopy. Journal of AOAC International, 78, 802-806.

Salvadori del Prato, O. (2001). Trattato di Tecnologia Casearia. Dairy Technology. Bologna: Edagricole-New Business Media.

Stocco, G. et al. (2019). Accuracy and biases in predicting the chemical and physical traits of many types of cheeses using different visible and near-infrared spectroscopic techniques and spectrum intervals. Journal of Dairy Science, 102, 9622-9638.

Strzałkowska, N. et al. (2009). Chemical composition, physical traits and fatty acid profile of goat milk as related to the stage of lactation. Animal Science Papers and Reports, 27, 311–320.

Williams, P. (2014). The RPD Statistic: A Tutorial Note. NIR News, 25, 22 - 26.

Wehling, R. L and Pierce, M. M. (1988). Determination of moisture in Cheddar cheese by near infrared reflectance spectroscopy. Journal of Association of Official Analytical Chemists, 71, 571-574.


Full Text:



  • There are currently no refbacks.

Copyright (c) 2020 Acta Fytotechnica et Zootechnica

© Slovak University of Agriculture in Nitra, Faculty of Agrobiology and Food Resources