HS-SPME-GC-MS combined with chemometrics to assess the impact of germination, dehulling, and milling on flavor attributes of brown and green lentils (Lens culinaris subsp. culinaris)

Abstract

The volatile profiles of raw, dehulled, and germinated seeds and flours of green and brown lentils ( Lens culinaris subsp. culinaris ) were assessed using headspace solid-phase micro-extraction coupled to gas chromatography-mass spectrometry (HS-SPME-GS-MS). The total identification percentages of the extracted volatiles ranged between 96.3% and 99.8%. Fifty-five aroma compounds were detected and, among them, 42 were determined in the emission of whole legume seeds and 37 from legume flours; they were classified in seven chemical classes, including monoterpene hydrocarbons (MH), oxygenated monoterpenes (OM), sesquiterpene hydrocarbons (STH), phenylpropanoids (PP), apocarotenes (AC), non-terpene derivatives (NTD), nitrogen/sulfur derivatives (NSD). OM volatiles increased during the germination process in both cultivars, while MH decreased significantly. In raw and germinated seeds and flours, the most representative class was NTD, except for germinated green flour (GGF), which emitted much more STH. Besides, milling the seeds resulted in an increase of MH (except for GGF), OM (except for GGF and germinated brown flour GBF ), STH, and PP and a decrease of NTD. The beany flavors associated with the volatile components increased because of germination and milling. Significant differences in the volatile profiles of the cultivars and their flours were evidenced due to the type of cultivar and processing conditions. This information may be of interest to industries involved in the development of specific pulse-based food product. • The aroma compounds of two lentil cultivars were evaluated using HS-SPME-GC-MS. • Effect of dehulling, germination, and milling on volatiles were assessed. • 55 emmited volatiles, which are divided into seven chemical groups, were detected. • A wide difference in the emission profiles of whole seeds and flours was observed. • This is useful in the conception of legume-based ingredients related to specific aroma.