Application Notebook - AGILENT FOOD TESTING SOLUTIONS

Importance of the topic

Food safety testing demands sensitive, accurate, and efficient analytical methods to detect a broad spectrum of chemical and biological contaminants in complex food matrices. Regulatory limits on pesticide residues, heavy metals, mycotoxins, and emerging flavor or authenticity markers require laboratories to employ cutting-edge instrumentation and streamlined sample preparation. Agilent’s comprehensive suite of applications addresses these challenges, offering high throughput, low detection limits, robust confirmation, and minimal matrix interference—ensuring consumer protection and compliance with global regulations.

Objectives and overview of the methods

• Detect and quantify organophosphorous pesticides in olive oil using GC with capillary flow technology (CFT) and QuEChERS extraction.
• Measure major, minor, and trace elements in food via 4100 MP-AES for low operating costs and robust performance.
• Determine fatty acid methyl esters (FAMEs) in salmon oil through automated derivatization on the 7696A WorkBench and rapid GC/FID.
• Screen for chemical contaminants (OCPs, PAHs, PCBs) in shellfish using modified QuEChERS and GC/MS/MS with post-column backflush.
• Profile medium-volatility sulfur aroma compounds in coffee by GC/Q-TOF with simple liquid–liquid extraction.
• Perform multi-element analysis of diverse foods on the 7700x ICP-MS in helium collision mode for trace metals and major elements in one run.
• Quantify PCDD/PCDF dioxins in food and feed by GC/MS/MS as a potential alternative to GC-HRMS, using retention-time locking and CFT backflush.
• Classify wine varieties (Pinot Noir, Merlot, Cabernet Sauvignon) by untargeted LC/Q-TOF metabolite profiling and statistical modeling in Mass Profiler Professional.
• Detect aflatoxins B1, B2, G1, G2 in cereals, peanuts, and nuts by LC/MS/MS with dispersive SPE and stable-isotope internal standards.
• Identify and confirm hundreds of pesticides in herbal extracts using triggered MRM on the 6460 triple quadrupole LC/MS, avoiding false positives.
• Analyze plant stanol esters in enriched margarine by online coupled LC–GC/FID in solvent-vent mode for high repeatability.

Methodology and instrumentation

• Sample preparation: Enhanced QuEChERS, dispersive SPE, liquid–liquid extraction, automated workbench derivatization, microwave digestion.
• Chromatography: Ultra Inert GC columns, multimode inlets (large-volume or solvent-vent injection), retention-time locking, post-column backflush.
• Mass spectrometry: GC/MS-SIM, GC/MS/MS MRM, GC/Q-TOF accurate mass, LC/MS/MS MRM (tMRM), 4100 MP-AES, 7700x ICP-MS in He collision cell mode.
• Data analysis: MassHunter and Mass Profiler Professional software for quantitation, spectral deconvolution, library matching, and multivariate modeling.

Main results and discussion

• GC/CFT with QuEChERS yielded detection limits of 10–15 ng/mL for 16 OP pesticides in olive oil, with recoveries >70%.
• 4100 MP-AES achieved ppt-level detection for elements (Al, Cd, Pb, Hg, etc.) in various certified reference food materials, meeting certified values.
• Automated FAME derivatization on the 7696A WorkBench delivered <1% RSD for EPA and DHA in salmon oil, with 20 min sample prep and 5 min GC runs.
• Modified QuEChERS plus GC/MS/MS MRM provided sensitive OCP, PAH, PCB screening in shellfish, meeting EU detection limits (0.1 µg/kg). CFT and backflush preserved chromatographic performance.
• GC/Q-TOF analysis of coffee extract detected sulfur volatiles at low ng/mL levels, achieving <5 ppm mass error and linearity across three orders of magnitude without 2D GC.
• 7700x ICP-MS in He mode measured major and trace metals in six foodstuffs in <3 min, with MDLs from tens of ppt to ppb and accurate results across certified samples.
• GC/MS/MS screening for PCDD/PCDF congeners met EU screening criteria down to low pg on column, offering a potential GC-MS/MS confirmation alternative to HRMS.
• Untargeted LC/Q-TOF profiling identified 26 000 entities in wines; statistical filtering and PLS-DA modeling in Mass Profiler Professional enabled 100% classification accuracy of three grape varieties.
• LC/MS/MS with jet stream and isotope-labeled standards quantified aflatoxins at sub-ppb levels in corn, wheat, peanuts, and nuts using dispersive SPE, avoiding expensive immuno-affinity cleanup.
• Triggered MRM on the 6460 LC/MS distinguished false positives for tebuthiuron in chamomile and tebufenpyrad in ginger by acquiring up to 10 product ions per analyte and library matching within one injection.
• Online LC–GC/FID using a multimode inlet with solvent-vent mode analyzed plant stanol esters in enriched margarine with R² >0.995, <9% RSD over >600 injections, without external pre-columns or solvent vents.

Benefits and practical applications of the methods

• High throughput: Many compounds per run, short runtimes, minimal carryover through backflush.
• Robust data: Retention-time locking, stable isotope internal standards, parameter-less automated quantitation.
• Cost savings: Reduced solvent use, avoidance of expensive cleanup columns, nitrogen-based plasmas lowering gas costs.
• Regulatory compliance: Methods meet or exceed EU, US, and Codex MRLs for pesticides, toxins, and contaminants.
• False positive/negative reduction: Triggered MRM and accurate mass libraries confirm analyte identity in one run.
• Versatility: A single ICP-MS method for trace and major elements; one LC/MS method for pesticides or toxins in diverse matrices.
• Scalability: Automated sample prep (7696A WorkBench), integrated GC–MS systems, and standardized software workflows accelerate lab adoption.

Future trends and potential applications

• Expansion of accurate mass screening for unknown contaminants using GC/Q-TOF and LC/Q-TOF with automated compound discovery.
• Further integration of sample prep automation with connectivity to informatics platforms for seamless compliance and data traceability.
• Use of tandem LC-MS and GC-MS techniques for speciation of metals and pesticide metabolites in complex food/feed matrices.
• Adoption of tMRM and data-independent acquisition strategies to detect emerging contaminants and adulterants.
• Development of comprehensive food product “fingerprinting” for authenticity, geographical origin, and process verification.

Conclusion

Agilent’s integrated food testing portfolio—from QuEChERS and automated sample prep to advanced LC/GC/MS and MP-AES/ICP-MS platforms—enables labs to address the full spectrum of contaminants in food and feed. These robust, high-performance methods deliver the sensitivity, selectivity, and throughput required to meet strict regulatory limits while reducing false results and operational costs. The combination of cutting-edge hardware, CFT backflush, retention-time locking, and intelligent software makes Agilent solutions the foundation for confident, compliant food safety testing today and into the future.

Reference

A complete list of application-specific references is provided in the original Agilent Food Testing Solutions Application Notebook (Agilent Technologies, Inc. 2012).