Geographical differentiation of garlic based on HS-GC-IMS combined with multivariate statistical analysis

Area of Science:

• Food Science and Technology
• Analytical Chemistry
• Agricultural Science

Background:

• Garlic is valued for its flavor and health benefits, with origin authentication crucial for quality control.
• Protected Geographical Indication (PGI) schemes are used for garlic authentication, but fraud is a concern.
• Reliable methods are needed to verify the geographical origin of garlic.

Purpose of the Study:

• To develop and validate a method for distinguishing garlic samples based on their geographical origin.
• To identify specific volatile organic compounds (VOCs) indicative of garlic's production area.
• To assess the efficacy of HS-GC-IMS combined with chemometrics for garlic authentication.

Main Methods:

• Analysis of volatile organic compounds (VOCs) in garlic samples from six distinct production areas using HS-GC-IMS.
• Application of multivariate statistical analyses, including Principal Component Analysis (PCA) and Orthogonal Partial Least Squares Discriminant Analysis (OPLS-DA).
• Identification of key aroma substances differentiating garlic origins using p-value and VIP score thresholds.

Main Results:

• A total of 26 VOCs were detected, with distinct patterns observed among samples from different regions.
• HS-GC-IMS generated visual fingerprint and topographic maps effectively illustrating sample variations.
• PCA and OPLS-DA successfully differentiated garlic samples based on geographical source, with 12 key aroma substances identified.

Conclusions:

• HS-GC-IMS coupled with multivariate statistical analysis provides a rapid, intuitive, and efficient method for garlic VOC analysis.
• This approach offers a novel strategy for authenticating garlic origin and ensuring product quality control.
• The identified aroma substances serve as reliable markers for distinguishing garlic from different producing areas.