{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,6]],"date-time":"2026-05-06T02:14:11Z","timestamp":1778033651353,"version":"3.51.4"},"reference-count":57,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2020,6,13]],"date-time":"2020-06-13T00:00:00Z","timestamp":1592006400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003141","name":"Consejo Nacional de Ciencia y Tecnolog\u00eda","doi-asserted-by":"publisher","award":["409071"],"award-info":[{"award-number":["409071"]}],"id":[{"id":"10.13039\/501100003141","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The present manuscript focuses on reviewing the optical techniques proposed to monitor milk quality in dairy farms to increase productivity and reduce costs. As is well known, the quality is linked to the fat and protein concentration; in addition, this issue is crucial to maintaining a healthy herd and preventing illnesses such as mastitis and ketosis. Usually, the quality of the milk is carried out with invasive methods employing chemical reagents that increase the time analysis. As a solution, several spectroscopy optical methods have been proposed, here, the benefits such as non-invasive measurement, online implementation, rapid estimation, and cost-effective execution. The most attractive optical methods to estimate fat and protein in cow\u2019s milk are compared and discussed considering their performance. The analysis is divided considering the wavelength operation (ultraviolet, visible, and infrared). Moreover, the weaknesses and strengths of the methods are fully analyzed. Finally, we provide the trends and a recent technique based on spectroscopy in the visible wavelength.<\/jats:p>","DOI":"10.3390\/s20123356","type":"journal-article","created":{"date-parts":[[2020,6,15]],"date-time":"2020-06-15T05:56:27Z","timestamp":1592200587000},"page":"3356","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":43,"title":["Optical Methods Based on Ultraviolet, Visible, and Near-Infrared Spectra to Estimate Fat and Protein in Raw Milk: A Review"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4526-1680","authenticated-orcid":false,"given":"Abraham","family":"Gast\u00e9lum-Barrios","sequence":"first","affiliation":[{"name":"Facultad de Ingenier\u00eda Campus Amazcala, Universidad Aut\u00f3noma de Quer\u00e9taro, Carr. Chichimequillas S\/N Km 1, Amazcala, El Marqu\u00e9s 76265, Mexico"}]},{"given":"Genaro M.","family":"Soto-Zaraz\u00faa","sequence":"additional","affiliation":[{"name":"Facultad de Ingenier\u00eda Campus Amazcala, Universidad Aut\u00f3noma de Quer\u00e9taro, Carr. Chichimequillas S\/N Km 1, Amazcala, El Marqu\u00e9s 76265, Mexico"}]},{"given":"Axel","family":"Escamilla-Garc\u00eda","sequence":"additional","affiliation":[{"name":"Facultad de Ingenier\u00eda Campus Amazcala, Universidad Aut\u00f3noma de Quer\u00e9taro, Carr. Chichimequillas S\/N Km 1, Amazcala, El Marqu\u00e9s 76265, Mexico"}]},{"given":"Manuel","family":"Toledano-Ayala","sequence":"additional","affiliation":[{"name":"Facultad de Ingenier\u00eda Campus Amazcala, Universidad Aut\u00f3noma de Quer\u00e9taro, Carr. Chichimequillas S\/N Km 1, Amazcala, El Marqu\u00e9s 76265, Mexico"}]},{"given":"Gonzalo","family":"Mac\u00edas-Bobadilla","sequence":"additional","affiliation":[{"name":"Facultad de Ingenier\u00eda Campus Amazcala, Universidad Aut\u00f3noma de Quer\u00e9taro, Carr. Chichimequillas S\/N Km 1, Amazcala, El Marqu\u00e9s 76265, Mexico"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7621-8573","authenticated-orcid":false,"given":"Daniel","family":"Jauregui-Vazquez","sequence":"additional","affiliation":[{"name":"Departamento de Electr\u00f3nica, Divisi\u00f3n de Ingenier\u00edas, Campus Irapuato-Salamanca, Universidad de Guanajuato, Carretera Salamanca-Valle de Santiago Km. 3.5+1.8 Comunidad de Palo Blanco, Salamanca, Guanajuato 36787, Mexico"}]}],"member":"1968","published-online":{"date-parts":[[2020,6,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"95","DOI":"10.1016\/j.jfoodeng.2015.10.017","article-title":"Spectral-sensitive Pulsed Photometry to predict the fat content of commercialized milk","volume":"171","author":"Ragni","year":"2016","journal-title":"J. Food Eng."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"5315","DOI":"10.3168\/jds.2011-4354","article-title":"Visible and near-infrared spectroscopic analysis of raw milk for cow health monitoring: Reflectance or transmittance?","volume":"94","author":"Aernouts","year":"2011","journal-title":"J. Dairy Sci."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"6727","DOI":"10.3168\/jds.2015-9630","article-title":"Visible and near-infrared bulk optical properties of raw milk","volume":"98","author":"Aernouts","year":"2015","journal-title":"J. Dairy Sci."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Olson, B.J.S.C., and Markwell, J. (2007). Assays for Determination of Protein Concentration. Current Protocols in Protein Science, John Wiley & Sons, Inc.","DOI":"10.1002\/0471140864.ps0304s48"},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Fox, P.F., Uniacke-Lowe, T., Mcsweeney, P.L.H., and O\u2019Mahony, J.A. (2015). Dairy Chemistry and Biochemistry, Springer. [2nd ed.].","DOI":"10.1007\/978-3-319-14892-2"},{"key":"ref_6","first-page":"115","article-title":"Theoretical Study of the Effect of Multi-Diameter Distribution on the Mie Scattering Characteristics of Milk Fat","volume":"22","author":"Yin","year":"2015","journal-title":"J. Harbin Inst. Technol."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"2028","DOI":"10.1364\/AO.41.002028","article-title":"Characterization of milk properties with a radiative transfer model","volume":"41","author":"Crofcheck","year":"2002","journal-title":"Appl. Opt."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1147","DOI":"10.13031\/2013.18488","article-title":"Effect of fat and casein particles in milk on the scattering of elliptically polarized light","volume":"48","author":"Crofcheck","year":"2005","journal-title":"Trans. Am. Soc. Agric. Eng."},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Stocker, S., Foschum, F., Krauter, P., Bergmann, F., Hohmann, A., Scalfi Happ, C., and Kienle, A. (2016). Broadband Optical Properties of Milk. Appl. Spectrosc., 1\u201312.","DOI":"10.1177\/0003702816666289"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"3929","DOI":"10.1364\/AO.56.003929","article-title":"Quantitative measurements of turbid liquids via structured laser illumination planar imaging where absorption spectrophotometry fails","volume":"56","author":"Regnima","year":"2017","journal-title":"Appl. Opt."},{"key":"ref_11","unstructured":"Hulst, H.C., and van de Hulst, H.C. (1981). Light Scattering by Small Particles, Courier Corporation."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"965","DOI":"10.1016\/j.saa.2016.09.037","article-title":"UV\u2013VIS absorption spectroscopy: Lambert-Beer reloaded","volume":"173","author":"Deniz","year":"2017","journal-title":"Spectrochim. Acta Part A Mol. Biomol. Spectrosc."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"858","DOI":"10.1016\/j.optlaseng.2005.02.007","article-title":"The rapid determination of fat and protein content in fresh raw milk using the laser light scattering technology","volume":"44","author":"Xin","year":"2006","journal-title":"Opt. Lasers Eng."},{"key":"ref_14","unstructured":"Jenkins, F.A., and White, H.E. (1937). Fundamentals of Optics, Tata McGraw-Hill Education."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"333","DOI":"10.1021\/ed039p333","article-title":"The Beer-Lambert law","volume":"39","author":"Swinehart","year":"1962","journal-title":"J. Chem. Educ."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"467","DOI":"10.1016\/B978-0-12-374407-4.00311-3","article-title":"Physical and Physico-Chemical Properties of Milk","volume":"Volume 3","author":"McCarthy","year":"2002","journal-title":"Encyclopedia of Dairy Sciences"},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Penner, M.H. (2017). Basic Principles of Spectroscopy. Food Analysis, Springer.","DOI":"10.1007\/978-3-319-45776-5_6"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"276","DOI":"10.3168\/jds.S0022-0302(70)86197-5","article-title":"Spectrophotometric Determination of Protein and Fat in Milk Simultaneously","volume":"53","author":"Nakai","year":"1969","journal-title":"J. Dairy Sci."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"207","DOI":"10.1016\/0308-8146(94)90160-0","article-title":"An ultraviolet spectrophotometric method to determine milk protein content in alkaline medium","volume":"49","author":"Kuaye","year":"1994","journal-title":"Food Chem."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"227","DOI":"10.1016\/S0003-2670(98)00823-X","article-title":"Determination of protein and casein in milk by fourth derivative UV spectrophotometry","volume":"393","author":"Puhan","year":"1999","journal-title":"Anal. Chim. Acta."},{"key":"ref_21","unstructured":"IDF Standard No 20-1 (2001). Determination of Nitrogen Content\u2014Part 1: Kjeldahl Method, International Dairy Federation."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"478","DOI":"10.3168\/jds.S0022-0302(05)72709-0","article-title":"Milk Fat Content Measurement by a Simple UV Spectrophotometric Method: An Alternative Screening Method","volume":"88","author":"Forcato","year":"2005","journal-title":"J. Dairy Sci."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"1255","DOI":"10.3168\/jds.S0022-0302(59)90730-1","article-title":"Photometric Milk Fat Determination","volume":"42","author":"Haugaard","year":"1959","journal-title":"J. Dairy Sci."},{"key":"ref_24","unstructured":"Muniz, R., Perez, M.A., de la Torre, C., Carleos, C.E., Corral, N., and Baro, J. (2009, January 6\u201311). A Comparison of Principal Component Regression (Pcr) and Partial Least Square (Pls) Methods in Prediction of Raw Milk Composition by Vis-Nir Spectrometry. Application to Development of on-Line Sensors for Fat, Protein and Lactose Contents. Proceedings of the XIX IMEKO World Congress Fundamental and Applied Metrology, Lisbon, Portugal."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"412","DOI":"10.1016\/j.foodchem.2012.02.077","article-title":"Quantitative determination of fat and total protein in milk based on visible light scatter","volume":"134","author":"Bogomolov","year":"2012","journal-title":"Food Chem."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"144","DOI":"10.1016\/j.talanta.2013.12.055","article-title":"Determination of fat and total protein content in milk using conventional digital imaging","volume":"121","author":"Kucheryavskiy","year":"2014","journal-title":"Talanta"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"129","DOI":"10.1016\/j.chemolab.2013.02.006","article-title":"Scatter-based quantitative spectroscopic analysis of milk fat and total protein in the region 400\u20131100nm in the presence of fat globule size variability","volume":"126","author":"Bogomolov","year":"2013","journal-title":"Chemom. Intell. Lab. Syst."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"15","DOI":"10.1016\/j.yofte.2018.11.019","article-title":"U-bent plastic optical fiber probes as refractive index based fat sensor for milk quality monitoring","volume":"47","author":"Gowri","year":"2019","journal-title":"Opt. Fiber Technol."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"273","DOI":"10.1017\/S0022029900018203","article-title":"Analysis of milk by infra-red absorption","volume":"31","author":"Goulden","year":"1964","journal-title":"J. Dairy Res."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"419","DOI":"10.1016\/0003-2670(93)85328-H","article-title":"Determination of the fat, protein and lactose content of milk using Fourier transform infrared spectrometry","volume":"284","author":"Luinge","year":"1993","journal-title":"Anal. Chim. Acta"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"64","DOI":"10.1021\/ac000469c","article-title":"Short-wave near-infrared spectroscopy of biological fluids. 1. Quantitative analysis of fat, protein, and lactose in raw milk by partial least-squares regression and band assignment","volume":"73","author":"Ozaki","year":"2001","journal-title":"Anal. Chem."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"599","DOI":"10.1366\/0003702021955150","article-title":"Development of a new measurement unit (MilkSpec-1) for rapid determination of fat, lactose, and protein in raw milk using near-infrared transmittance spectroscopy","volume":"56","author":"Woo","year":"2002","journal-title":"Appl. Spectrosc."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"2779","DOI":"10.3168\/jds.S0022-0302(04)73405-0","article-title":"Determination of protein concentration in raw milk by mid-infrared fourier transform infrared\/attenuated total reflectance spectroscopy","volume":"87","author":"Etzion","year":"2004","journal-title":"J. Dairy Sci."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"160","DOI":"10.1366\/0003702971940080","article-title":"Infrared spectroscopy in aqueous solution: Difficulties and accuracy of water subtraction","volume":"51","author":"Rahmelow","year":"1997","journal-title":"Appl. Spectrosc."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1007\/s11694-006-9001-x","article-title":"Near-infrared spectroscopic sensing system for online monitoring of milk quality during milking","volume":"1","author":"Kawamura","year":"2007","journal-title":"Sens. Instrum. Food Qual. Saf."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"22","DOI":"10.1016\/j.compag.2008.01.006","article-title":"Near-infrared spectroscopic sensing system for on-line milk quality assessment in a milking robot","volume":"63","author":"Kawasaki","year":"2008","journal-title":"Comput. Electron. Agric."},{"key":"ref_37","first-page":"873","article-title":"Medici\u00f3n Del Porcentaje De Grasa En Leche L\u00edquida Usando \u201cTapers\u201d De Fibra \u00d3ptica","volume":"43","year":"2011","journal-title":"Revista Colombiana de F\u00edsica"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"6465","DOI":"10.3168\/jds.2012-5388","article-title":"Accuracy of in-line milk composition analysis with diffuse reflectance near-infrared spectroscopy","volume":"95","author":"Melfsen","year":"2012","journal-title":"J. Dairy Sci."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"15","DOI":"10.1007\/s40242-013-2191-y","article-title":"Portable analyzer for rapid analysis of total protein, fat and lactose contents in raw milk measured by non-dispersive short-wave near-infrared spectrometry","volume":"29","author":"Feng","year":"2013","journal-title":"Chem. Res. Chin. Univ."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"1471","DOI":"10.1177\/0142331215593994","article-title":"A rapid method for measuring fat content in milk based on W-type optical fibre sensor system","volume":"38","author":"Zhu","year":"2016","journal-title":"Trans. Inst. Meas. Control"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"1853","DOI":"10.3168\/jds.2015-10318","article-title":"Short communication: Selecting the most informative mid-infrared spectra wavenumbers to improve the accuracy of prediction models for detailed milk protein content","volume":"99","author":"Niero","year":"2016","journal-title":"J. Dairy Sci."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"131","DOI":"10.14257\/ijmue.2016.11.10.12","article-title":"Research on Rapid Detection Method of Protein and Fat in Raw Milk Based on Mid-infrared Spectrum","volume":"11","author":"Li","year":"2016","journal-title":"Int. J. Multimed. Ubiquitous Eng."},{"key":"ref_43","doi-asserted-by":"crossref","unstructured":"Tremblay, L., Laporte, M.F., L\u00e9onil, J., Dupont, D., and Paquin, P. (2003). Quantitation of Proteins in Milk and Milk Products. Advanced Dairy Chemistry\u20141 Proteins, Springer US.","DOI":"10.1007\/978-1-4419-8602-3_2"},{"key":"ref_44","doi-asserted-by":"crossref","unstructured":"Dave, A., Banwari, D., Mansinghani, S., Srivastava, S., and Sadistap, S. (2016, January 22\u201325). Ultrasonic Sensing System for Detecting Water Adulteration in Milk. Proceedings of the 2016 IEEE Region 10 Conference (TENCON), Singapore.","DOI":"10.1109\/TENCON.2016.7848424"},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"118","DOI":"10.1016\/j.snb.2006.05.013","article-title":"Design and construction of a low cost single-supply embedded telemetry system for amperometric biosensor applications","volume":"122","author":"Serra","year":"2007","journal-title":"Sensors Actuators B Chem."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"8963","DOI":"10.3390\/s101008963","article-title":"A monitoring system for vegetable greenhouses based on a wireless sensor network","volume":"10","author":"Li","year":"2010","journal-title":"Sensors"},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"95","DOI":"10.1016\/j.micpro.2007.09.001","article-title":"Design and evaluation of a hardware\/software FPGA-based system for fast image processing","volume":"32","author":"Kalomiros","year":"2008","journal-title":"Microprocess. Microsyst."},{"key":"ref_48","doi-asserted-by":"crossref","unstructured":"Andonovic, I., Michie, C., Cousin, P., Janati, A., Pham, C., and Diop, M. (2018, January 4\u20137). Precision Livestock Farming Technologies. Proceedings of the 2018 Global Internet of Things Summit (GIoTS), Bilbao, Spain.","DOI":"10.1109\/GIOTS.2018.8534572"},{"key":"ref_49","first-page":"995817","article-title":"Generation of supercontinuum light in micro-structured fiber and polarization study at different wavelengths","volume":"Volume 9958","year":"2016","journal-title":"Photonic Fiber and Crystal Devices: Advances in Materials and Innovations in Device Applications X"},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"129","DOI":"10.1109\/50.64932","article-title":"Fiber-optic Fabry-Perot temperature sensor using a low-coherence light source","volume":"9","author":"Lee","year":"1991","journal-title":"J. lightwave Technol."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"93","DOI":"10.1016\/j.yofte.2018.07.001","article-title":"A Mach-Zehnder interferometer-based High Sensitivity Temperature sensor for human body monitoring","volume":"45","author":"Wang","year":"2018","journal-title":"Opt. Fiber Technol."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"1387","DOI":"10.1109\/LPT.2008.926832","article-title":"Single-mode fiber refractive index sensor based on core-offset attenuators","volume":"20","author":"Tian","year":"2008","journal-title":"IEEE Photonics Technol. Lett."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"2467","DOI":"10.3390\/s120302467","article-title":"Interferometric fiber optic sensors","volume":"12","author":"Lee","year":"2012","journal-title":"Sensors"},{"key":"ref_54","doi-asserted-by":"crossref","unstructured":"Gast\u00e9lum-Barrios, A., Soto-Zaraz\u00faa, G.M., Garc\u00eda-Trejo, J.F., Sierra-Hernandez, J.M., and Jauregui-Vazquez, D. (2019). A new method for total fat detection in raw milk based on dual low-coherence interferometer. Sensors, 19.","DOI":"10.3390\/s19204562"},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"4","DOI":"10.1016\/j.biosystemseng.2018.10.014","article-title":"Smart farming IoT platform based on edge and cloud computing","volume":"177","author":"Santa","year":"2019","journal-title":"Biosyst. Eng."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"100","DOI":"10.1016\/j.cofs.2017.11.004","article-title":"Applications of spectroscopic techniques for fat and fatty acids analysis of dairy foods","volume":"17","author":"Tao","year":"2017","journal-title":"Curr. Opin. Food Sci."},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"1159","DOI":"10.1021\/jf703712w","article-title":"Performance comparison of UV and FT-raman spectroscopy in the determination of conjugated linoleic acids in cow milk fat","volume":"56","author":"Bernuy","year":"2008","journal-title":"J. Agric. Food Chem."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/20\/12\/3356\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T09:38:33Z","timestamp":1760175513000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/20\/12\/3356"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,6,13]]},"references-count":57,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2020,6]]}},"alternative-id":["s20123356"],"URL":"https:\/\/doi.org\/10.3390\/s20123356","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2020,6,13]]}}}