MIR and Vis/NIR spectroscopy cannot authenticate organic bulk milk. Issue 1 (1st January 2021)

• Record Type: Journal Article
• Authors: Manuelian, Carmen L.; Vigolo, Vania; Righi, Federico; Simoni, Marica; Burbi, Sara; De Marchi, Massimo
• Is Part Of: Italian journal of animal science. Volume 20:Issue 1(2021)
• Page Start: 1810
• Page End: 1816
• Publication Date: 2021-01-01
• Subjects: Infrared -- organic milk -- PCA -- PLS-DA; Animal culture -- Periodicals; Livestock -- Italy -- Periodicals; Veterinary medicine -- Italy -- Periodicals; Animal culture; Livestock; Veterinary medicine; Italy; Periodicals; Periodicals; 636.005
• DOI: 10.1080/1828051X.2021.1954559
• Languages: English
• ISSNs: 1828-051X

Abstract

Abstract: This study aimed to evaluate the feasibility of mid-infrared (MIR; 5000–900 cm −1 ) and visible/near-infrared (Vis/NIR; 400–2500 nm) spectroscopy to discriminate organic (ORG) from conventional (CONV) bulk milk. Samples ( n = 225) from 24 farms (ORG, n = 12; CONV, n = 12) located in the same area, mainly rearing Holstein-Friesian cows, under similar management conditions, except for ORG livestock spending a period of time on pasture, were collected from September 2019 to August 2020. Chemical composition of the lactation ration was similar between groups. Mid-infrared and Vis/NIR spectrum of each sample were collected. Principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA) were done using R software. For the PLS-DA, records were divided in a train set (8 farms/group) and a test set (4 farms/group), and only wavelengths with VIP >1 were retained. The PCA was not able to discriminate both groups. The PLS-DA revealed an accuracy of the model in the test set of 54.1% and 62.9%, for MIR and Vis/NIR, respectively. In conclusion, both infrared regions performed similarly, and the moderate accuracy of the PLS-DA could be related to the similarity of the selected farms between both categories. Highlights: Infrared spectra from bulk milk samples of organic and conventional farms were similar. Low accuracy using partial least squares-discriminant analysis. Both MIR and Vis/NIR infrared regions performed similarly.