Processing of Flavor-Enhanced Oils: Optimization and Validation of Multiple Headspace Solid-Phase Microextraction-Arrow to Quantify Pyrazines in the Oils

Abstract

An efficient and effective multiple headspace-solid phase microextraction-arrow-gas chromatography-mass spectrometry (MHS-SPME-arrow-GCMS) analytical protocol is established and used to quantify the flavor compounds in oils. SPME conditions, such as fiber coating, pre-incubation temperature, extraction temperature, and time were studied. The feasibility was compared between SPME-arrow and the traditional fiber by loading different sample amounts. It was found that the SPME-arrow was more suitable for the MHS-SPME. The limit of detection (LODs) and limit of quantitation (LOQs) of pyrazines were in the range of 2–60 ng and 6–180 ng/g oil, respectively. The relative standard deviation (RSD) of both intra- and inter-day were lower than 16%. The mean recoveries for spiked pyrazines in rapeseed oil were in the range of 91.6–109.2%. Furthermore, this newly established method of MHS-SPME-arrow was compared with stable isotopes dilution analysis (SIDA) by using [2H6]-2-methyl-pyrazine. The results are comparable and indicate this method can be used for edible oil flavor analysis.

Simple and Rapid Method for the Quantitation of Trace-Level 3-Alkyl-2-methoxypyrazines in Fragrant Vegetable Oils by Gas Chromatography–Tandem Mass Spectrometry

“…We had optimized the SPME-Arrow-GC−MS method for flavor analysis in the early work. 20 However, in the current concern, the mass sensitivity of the three MPs was almost close to the baseline because of the extremely low concentration and mass background interference. Thus, the method is not good enough for the MP analysis.…”

“…The standard of the three MPs in the fragrant oil with different concentrations (1, 5, 10, 20, 50, and 100 μg/L) were used for the testing by the optimized HS-SPME-Arrow-GC− MS/MS-MRM method. 20 The LODs in the oil were 5 μg/kg for IPMP and 10 μg/kg for both SBMP and IBMP according to the signal-noise ratio. Thus, the currently developed method is 50-fold more sensitive, indicating a high potential for use.…”

“…HS-SPME has become a popular and reliable method used to assess pyrazines lately. We had optimized the SPME-Arrow-GC–MS method for flavor analysis in the early work . However, in the current concern, the mass sensitivity of the three MPs was almost close to the baseline because of the extremely low concentration and mass background interference.…”

“…Thus, the method is not good enough for the MP analysis. The standard of the three MPs in the fragrant oil with different concentrations (1, 5, 10, 20, 50, and 100 μg/L) were used for the testing by the optimized HS-SPME-Arrow-GC–MS/MS-MRM method . The LODs in the oil were 5 μg/kg for IPMP and 10 μg/kg for both SBMP and IBMP according to the signal-noise ratio.…”

“…These procedures require relatively high sample amounts and are laborious, time-consuming, as well as expensive, although these techniques were used in most cases to screen the key volatile odorants. Several other studies have reported the existence of MPs in wine grapes and wine samples with headspace solid phase microextraction (HS-SPME) and GC–MS. − HS-SPME is an extraction technique with fast, automated, and solvent-free features; however, most HS-SPME methods are unable to analyze MPs in fragrant oils − due to instrument sensitivity limitations (Table ). Flavor compounds with reduced vapor pressures are highly soluble in oils compared to wine or water matrices, making MP analysis in fragrant oils a big challenge.…”