Foods, Flavors & Fragrances Solutions

Foods, Flavors & Fragrances Solutions

Labeled Pesticide Residue Internal Standards for Food Analysis

  • Isotopically labeled to provide the best approach for pesticide residue quantification.
  • Multiple options let you choose internal and surrogate standards that will mitigate matrix effects.
  • Economically priced and compatible with both LC-MS and GC-MS applications; even helpful for optimizing LC-MS/MS system performance.
  • Restek is your complete supplier for world-class food safety analysis: pesticide reference standard mixes and internal/surrogate standards, GC and LC columns, QuEChERS, and more!

MOSH/MOAH Standard (9 components)

  • Developed specifically for using LC coupled with GC-FID to accurately determine hydrocarbons found in mineral oils, which can migrate from packaging into food.
  • This 9-component mix contains non-interfering internal standards as well as both mineral oil saturated hydrocarbon (MOSH) and mineral oil aromatic hydrocarbon (MOAH) markers to correctly cut fractions.
  • Restek is your complete supplier for world-class MOSH/MOAH analysis: reference standards, Allure silica LC columns, Rxi-5Sil MS GC columns, accessories, and more!

LC Multiresidue Pesticide Kit

  • Accurately detect and quantify pesticides of global food safety concern in a wide range of fruits, vegetables, and other commodities by LC-MS/MS.
  • Full kit contains 204 compounds of interest, covering many LC-determined pesticides listed by government agencies; individual ampuls also sold separately.

GC Multiresidue Pesticide Kit

  • Accurately identify and quantify pesticide residues by GC-MS/MS in fruits, vegetables, botanicals, and herbals such as tea, ginseng, ginger, echinacea, and dietary supplements.
  • Comprehensive 203-compound kit covers food safety lists by the FDA, USDA, and other global governmental agencies; individual ampuls also sold separately.

Everything you need for QuEChERS!

  • Fast, simple sample extraction and cleanup using dSPE—Fourfold increases in sample throughput.
  • Complete offering for AOAC and European Methods.
  • Single and multiple component standards as specified in EN Method 15662.

Rxi-5Sil MS Columns (fused silica)

low-polarity phase; Crossbond 1,4-bis(dimethylsiloxy)phenylene dimethyl polysiloxane

  • Engineered to be a low-bleed GC-MS column.
  • Excellent inertness for active compounds.
  • General-purpose columnsideal for GC-MS analysis of semivolatiles, polycyclic aromatic compounds, chlorinated hydrocarbons, phthalates, phenols, amines, organochlorine pesticides, organophosphorus pesticides, drugs, solvent impurities, and hydrocarbons.
  • Temperature range: -60 °C to 350 °C.

Flip Seal Dual Vespel Ring Inlet Seals

Restek Innovation! Patented.

Reversible Flip Seal Inlet SealSame Cost, Extended Lifetime
  • Reversible, two-sided design allows significantly more analyses than other seals, at the same pricesimply use, flip, then use again!
  • Vespel ring embedded in top and bottom surface eliminates need for a washer.
  • Highly inert gold or Siltek-deactivated seals reduce breakdown and adsorption of active compounds, maximizing component transfer to GC column.
  • Very little torque required to make sealreduces operator variability.

Thermal Desorption (TD) Products

Thermal desorption (TD) tubes in a variety of styles, grab samplers, multiple tube sequential samplers, sampling pumps, and accessories.

Ultra Aqueous C18 Columns (USP L1)

Particle Size: 3 µm or 5 µm, spherical
Pore Size: 100 Å
Carbon Load: 15%
End-Cap: no
pH Range: 2.5 to 8
Temperature Limit: 80 °C
USP Phase Code: L1
Phase Category: modified C18
Ligand Type: proprietary polar modified and functionally bonded C18


for Agilent HPLC Systems

Xenon Lamps

for Waters Detectors

Deuterium Lamps

for Waters Detectors

Introduction to QuEChERS

Jack Cochran, Director of New Business and Technology at Restek, gives a brief overview of the QuEChERS process, and how it can simplify your sample preparation workflow.

Analysis of Veterinary Drug Residues using a Unique HPLC Biphenyl Stationary Phase

Analysis of veterinary drug residues in milk using a QuEChERS approach and Biphenyl column is discussed. Better retention is achieved, compared to C18 or phenyl phases, improving separation of analytes and matrix components.
Narrated by Julie Kowalski, Foods, Flavors & Fragrances Applications Chemist. Length: 24 minutes

Technical Articles

Clinical, Forensic & Toxicology

Analysis of Synthetic Cannabinoids and Metabolites: Adding New Compounds to an Existing LC-MS/MS Method

The analysis of synthetic cannabinoids and their metabolites can be a difficult and challenging task. Keeping up with the ever-growing list of synthetic cannabinoids that illicit drug makers produce further complicates the analysis. As shown here, the retention and selectivity of the Raptor Biphenyl column allows new drugs to be added to an existing method, providing labs with an important vehicle for improving efficiency and productivity.

Foods, Flavors & Fragrances

Highly Reproducible Detailed cis/trans FAMEs Analysis Ensured by New Optimized Rt-2560 Column Manufacturing and Application-Specific QC Test

Even minor variations in manufacturing processes can potentially have detrimental effects on column-to-column reproducibility. As shown here, Rt-2560 GC columns produced using a newly updated and optimized manufacturing process exhibit high reproducibility and provide consistent performance for detailed cis/trans FAMEs analysis.

Foods, Flavors & Fragrances

Rt-2560 Columns Ensure Accurate, Reliable AOAC 996.06 and AOCS Ce 1j-07 FAMEs Analysis

Restek has optimized the manufacturing process and implemented a new, application-specific QC testing procedure for all new Rt-2560 columns (cat.# 13198). Here we demonstrate that, Rt-2560 columns produced using the optimized process exhibit excellent performance for both AOAC 996.06 and AOCS Ce 1j-07 FAMEs analysis and meet all method requirements.

Foods, Flavors & Fragrances

Analysis of Nicotine and Impurities in Electronic Cigarette Solutions and Vapor

Despite the growing popularity of electronic cigarettes, relatively little work has been done to characterize their vapor. In this study, we developed a quick, simple thermal desorption device for sampling vapor, as well as methods for analyzing vapor and solutions to determine nicotine content (GC-FID) and impurity profiles (GC-MS). This novel approach, which utilizes an Rtx®-VMS column, provides detectable levels of volatile organic compounds (VOCs) and semivolatile organic compounds (SVOCs) from a single 40 mL puff.

Foods, Flavors & Fragrances

Analytical Method for Polycyclic Aromatic Hydrocarbons (PAHs) in Yerba Mate Tea Using Modified QuEChERS, Solid Phase Extraction and GC-TOFMS and GC-MS/MS

This application note describes the development of an analytical method for PAHs in tea that allows analysts to more quickly and accurately characterize target PAHs. Sample preparation is based on a modified QuEChERS extraction and solid phase extraction sample cleanup. Both GC-TOFMS and GC-MS/MS techniques were used and analyses were optimized for resolution of isobaric compounds, as well as for maintaining a reasonable analysis time.

Foods, Flavors & Fragrances

A Preliminary FET Headspace GC-FID Method for Comprehensive Terpene Profiling in Cannabis

This application note describes an FET-HS-GC-FID method that was developed in hops for the analysis of terpenes in cannabis. Good chromatographic separation allowed quantification of critical compounds across the volatility range, including α-pinene, β-myrcene, α-humulene, β-caryophyllene, and caryophyllene oxide.

Foods, Flavors & Fragrances

Don’t Overestimate Cannabidiol During Medical Cannabis Potency Testing by Gas Chromatography

Proper GC column choice is essential for accurate and robust medical cannabis potency testing. Using an Rxi-35Sil MS column under the instrument conditions shown here allows fast, accurate reporting of cannabichromene and cannabidiol in medical marijuana samples.

Foods, Flavors & Fragrances

High-Quality Analysis of Pesticides in Cannabis Using QuEChERS, Cartridge SPE Cleanup, and GCxGC-TOFMS

As medical marijuana is more frequently prescribed, patient safety must be ensured. Pesticide residue testing is an important part of assuring safe product is dispensed, but analysis can be extremely challenging due to matrix complexity. The use of QuEChERS, cartridge SPE cleanup, and GCxGC-TOFMS as presented here produces high-quality quantitative data for this difficult analysis.

Foods, Flavors & Fragrances

Evaluation of Dispersive and Cartridge Solid Phase Extraction (SPE) Cleanups for Multiresidue Pesticides in QuEChERS Extracts of Finished Tobacco Using GCxGC-TOFMS

We compared the efficacy of dSPE and cSPE cleanup methods for multiresidue pesticide analysis of QuEChERS extracts of finished tobacco products using GCxGC-TOFMS. Cleanup with dSPE tubes containing 7.5 mg of GCB and 25 mg of PSA produced better results than other methods, with average recoveries of 92% and 91% for 500 ppb and 50 ppb fortifications respectively.

Foods, Flavors & Fragrances

A Comprehensive Approach to Pesticide Residue Testing, Including Non-Target Analysis, for Fruits, Vegetables, and Nuts, Using QuEChERS, LC-MS/MS, and GCxGC-TOFMS

Food commodities that varied in water, fat, and pigment content were fortified with pesticides and processed using a QuEChERS sample preparation technique. Samples were analyzed by both GCxGC-TOFMS and LC-MS/MS, and good recoveries were obtained for most pesticides in most commodities.

Foods, Flavors & Fragrances

Increase Data Quality for Sulfonamide Residue Analysis by HPLC and UHPLC Using Unique Biphenyl Column Selectivity

The unique selectivity and high retention of Biphenyl columns produce complete separation of sulfonamide residues and benefit both UV and MS detection. In addition, Biphenyl columns in a UHPLC format allow faster sample throughput when testing for these antibiotics.


Matrix Effects in Multi-Residue Pesticide Analysis When Using Liquid Chromatography-Tandem Mass Spectrometry

Matrix effects present a significant challenge to multi-residue pesticide analysis of food samples using LC/MS/MS. In this editorial, Dr. Kai Zhang, of the FDA Center for Food Safety and Applied Nutrition, discusses approaches that minimize matrix effects.

Foods, Flavors & Fragrances

Comparing Pesticide Residues in Amish and Commercially Grown Strawberries and Spinach Using QuEChERS, Various dSPE Sorbents, and GC-TOFMS

QuEChERS extraction, dSPE cleanup, and GC-TOFMS analysis were used to assess pesticide residue levels in strawberry and spinach from both commercial and Amish growers. Various dSPE sorbent products were compared to determine which were most effective.

General Interest

Pesticides in Dietary Supplements: - Advantages of QuEChERS vs. PAM 303

Restek has developed the first QuEChERS-based method for determining pesticide residues in dietary supplements. This simple, cost-effective procedure reduces matrix interferences as well as sample prep variation among technicians.

Foods, Flavors & Fragrances

Comprehensive Pesticide Residue Analysis by LC-MS/MS Using an Ultra Aqueous C18 Column

Analysis of pesticide residues in foods is complicated by the large number of target compounds. LC-MS/MS analysis using an Aqueous C18 column provides more comprehensive results than GC alone.

Foods, Flavors & Fragrances

Using Thermal Desorption to Enhance Aroma Profiling by GC/MS - Lower Detection Limits with Latest Technology

Thermal desorption offers an automatic, high-sensitivity alternative to conventional liquid extraction methods for aroma profiling by GC/MS. It allows vapor profile constituents to be cleanly separated from the sample matrix and often facilitates selective purging of volatile interferences. This ensures that the vapor profile analyzed is most representative of the aroma perceived by consumers and that key compounds can be identified and measured at the lowest levels possible.

General Interest

Dual Vespel® Ring Inlet Seals - Washerless, Leak-Tight Seals for Agilent GCs

Restek's Dual Vespel® Ring inlet seal gives you a better seal with fewer parts. Data show that the soft Vespel® material has a much lower leak rate than a metal seal. Also, since less torque is required for installation, user variability is reduced.

PDF Document

Determining Pesticides in Dietary Supplements with QuEChERS Extraction, Cartridge SPE, and GCxGC-TOFMS

The novel approach used here combines QuEChERS extraction, cartridge SPE cleanup, and GCxGC-TOFMS analysis, resulting in good recoveries for a wide range of pesticides in dietary supplements. Matrices include dandelion root, sage, and a multi-herb finished product. (PDF - 394kB)

PDF Document

New Rxi-PAH GC Column; Resolve Important Isobaric Polycyclic Aromatic Hydrocarbons for Food Safety and Environmental Methods

Separate isobaric polycyclic aromatic hydrocarbons, including priority EFSA PAH4 compounds benz[a]anthracene, chrysene, benzo[b]fluoranthene, and benzo[a]pyrene, easily and accurately on an Rxi-PAH column. Whether you need more resolution or faster analysis, these new GC columns offer the selectivity and efficiency you need for food safety and environmental PAH analysis. (PDF - 826kB)

PDF Document

Accurately Determine Mineral Oil Hydrocarbons in Food and Packaging

Accurate testing for mineral oil hydrocarbons (MOHs) in food and packaging is imperative to the safety of our food supply. Turn to Restek for the certified reference materials (CRMs), HPLC columns, GC guard columns, and GC analytical columns you need for world-class analysis of mineral oil saturated hydrocarbons (MOSH) and mineral oil aromatic hydrocarbons (MOAH) via online LC/GC coupling. (PDF - 1193kB)

PDF Document

Mitigating Matrix Effects: Examination of Dilution, QuEChERS, and Calibration Strategies for LC-MS/MS Analysis of Pesticide Residues in Diverse Food Types

LC-MS/MS is popular for monitoring pesticide residues in food due to its selectivity and sensitivity; however, matrix effects can cause poor data quality and difficult quantification. We evaluated the relative effectiveness of sample dilution, QuEChERS cleanup, solvent-based calibration, and matrix-matched calibration strategies to mitigate matrix effects in celery, kale, avocado, lime, and brown rice flour. (PDF - 597kB)

PDF Document

NEW! Rx-1301Sil MS GC Columns

The new Rxi-1301Sil MS column is ideal for the analysis of multiple compound classes across a range of polarities and volatilities. With its cyano-based selectivity and high thermal stability, it is the best 1301-type column for robust MS analyses. (PDF - 2143kB)

PDF Document

HPLC Analysis of Glucosinolates in Vegetable Extracts without Ion Pairing Using an Ultra Aqueous C18 Column

Glucosinolates with hydrophilic functional groups are very difficult to retain by conventional reversed phase HPLC, and when the functional groups in a sample are diverse, polarity can differ widely, complicating the problem. Until now, reversed phase HPLC with an ion pairing reagent has been the inconvenient, but necessary, approach to these analyses. This 2-page note describes a column and conditions for analyses of glucosinolates, without ion pairing. (PDF - 435kB)

PDF Document

Thermal Desorption: A Practical Applications Guide: IV. Food, Flavour, Fragrance & Odour Profiling

Thermal desorption is used extensively for measuring volatile and semivolatile components in foods, flavors, fragrances, and odors. This 28-page publication from Markes International Ltd. presents several key applications. (PDF - 1952kB)

PDF Document

Fast, Simple QuEChERS Extraction and Cleanup of Pesticide Residue Samples

QuEChERS dSPE methods simplify extract cleanup, reduce material costs, and improve sample throughput. Here we demonstrate the effectiveness of QuEChERS sample cleanup using a multiresidue analysis of pesticides on strawberries. (PDF - 1180kB)