Research progress on detection of 2-acetyl-1-pyrroline, the characteristic aroma component of fragrant rice

Abstract

2-Acetyl-1-pyrroline (2-AP) has been identified as the characteristic aroma component of fragrant rice, and its concentration determines the quality and price of the rice. However, obtaining accurate assay results with modern analytical instruments remains a major challenge. The two reasons for this setback are the ultralow concentration of 2-AP in samples and the serious interferences in its determination. In natural fragrant rice, the concentration of 2-AP is very low, at the μg/kg level. The interferences mainly originate from the sample matrix or due to co-elution during chromatographic separation. In the present paper, various methods for the sample pretreatment and instrumental analysis of 2-AP in rice are reviewed. The sample pretreatment methods include distillation, extraction, and headspace enrichment procedures. Common instrumental analytical methods include gas chromatography (GC) or GC-mass spectrometry (MS), GC-olfactometry, and derivatization-high performance liquid chromatography-MS/MS developed by the researchers recently. The present review will provide a reference for the determination of 2-AP in the food trade, the research on fragrant rice breeding as well as the management of water and fertilizers in agriculture, and the development of stabilized flavor compounds of fragrant rice scent in food processing.