A Case Study for Geographical Indication of Organic Milk in Korea using Stable Isotope Ratios-based Chemometric Analysis

This study aimed to examine regional δ13C, δ15N, δ18O, and δ34S variations of organic milk in Korea and to develop a differentiation model to identify isotope markers. Herein, δ13C, δ15N, δ18O, and δ34S were quantified in organic milk, using a stable isotope ratio mass spectrometer and developed differentiation models through pairwise comparisons using orthogonal projection to latent structure-discriminant analysis, which displayed excellent predictability (Q2cum ≥ 0.828) among Boryeong, Gochang, and Jeju regions and good predictability (Q2cum ≥ 0.503) for Hoengseong-related regions. The δ13C value was the most important influencer, and the prediction plots by an external validation among Boryeong, Gochang, and Jeju regions accurately predicted the geographical origin of the test milk samples with below 5% of probability of wrong classification. Our results show regional δ13C, δ15N, δ18O, and δ34S signatures in Korea, thereby potentially expanding global isotope ratio databases for reliable geographical indication of organic milk.
Source: Food Control - Category: Food Science Source Type: research