Provenance profiling: SN- and LA-ICP-MS based authentication of strawberries.

Area of Science:

• Food Science
• Analytical Chemistry
• Agricultural Economics

Background:

• Strawberry prices vary significantly based on origin, creating incentives for food fraud.
• Distinguishing the geographical origin of strawberries is crucial for consumer trust and fair trade.
• Existing methods for provenance determination can be time-consuming and reagent-intensive.

Purpose of the Study:

• To develop and compare two sample preparation techniques for determining strawberry provenance.
• To investigate the effectiveness of ICP-MS combined with multivariate data analysis for classifying strawberry origins.
• To evaluate the feasibility of laser ablation as a resource-efficient alternative to acid digestion.

Main Methods:

• Analysis of 403 strawberry samples from six countries using Inductively Coupled Plasma Mass Spectrometry (ICP-MS).
• Comparison of two sample preparation methods: acid digestion with solution nebulization (SN-ICP-MS) and laser ablation (LA-ICP-MS).
• Application of multivariate data analysis for developing classification models to distinguish strawberry origins.

Main Results:

• Solution nebulization achieved a 91.7% accuracy in distinguishing German from imported strawberries.
• Strawberry seeds proved to be an optimal matrix for the laser ablation method.
• Laser ablation yielded a two-class classification model with 88.0 ± 12.1% accuracy.

Conclusions:

• Both SN-ICP-MS and LA-ICP-MS are effective for determining strawberry provenance.
• LA-ICP-MS presents a more innovative, resource-efficient, and time-saving approach compared to traditional methods.
• These techniques offer realistic tools for detecting food fraud in the strawberry market.