Effects of microwave and enzymatic pretreatments on lipid concomitants and volatile profiles of safflower seed oil: complementary HS-SPME-GC-MS and HS-GC-IMS analyses of volatiles

Safflower seed oil is rich in linoleic acid, but pretreatments used before extraction may alter its physicochemical quality, lipid concomitants, and volatile composition. However, the effects of sequential microwave and enzymatic pretreatments on these characteristics remain insufficiently understood. This study compared oils obtained from untreated seeds and seeds subjected to microwave, enzyme-assisted, or sequential microwave–enzyme pretreatment. Physicochemical properties, fatty acids, tocopherols, phytosterols, and volatile profiles were evaluated using complementary headspace solid-phase microextraction–gas chromatography–mass spectrometry and headspace gas chromatography–ion mobility spectrometry. All pretreatments decreased oil lightness and increased redness and yellowness. Acid values increased after pretreatment, whereas peroxide values increased mainly in oils from microwave-treated seeds; the enzyme-treated oil remained comparable to the untreated oil. The high-linoleic fatty acid pattern was retained, with unsaturated fatty acids accounting for approximately 90% of total fatty acids. Alpha-tocopherol concentrations remained stable at 640.67–679.60 mg/kg. Total phytosterol concentrations were 350.15, 357.18, 376.10, and 389.71 mg/100 g in oils from untreated, microwave-treated, enzyme-treated, and sequentially treated seeds, respectively; the enzyme-containing treatments produced significantly higher values than the untreated and microwave-only treatments. Total semiquantitative volatile abundance increased from 6.20 × 10 3 µg/kg in untreated oil to 4.62 × 10 4 , 9.44 × 10 4 , and 1.56 × 10 5 µg/kg after enzyme-assisted, microwave, and sequential pretreatments, respectively. Enzyme-assisted pretreatment produced an acid-dominated profile, whereas microwave pretreatment was associated mainly with pyrazines, pyrroles, furans, and aldehydes. Sequential treatment produced the highest overall volatile abundance and a broader distribution of nitrogen-containing heterocycles, alcohols, phenolic volatiles, aldehydes, acids, and esters. Multivariate analyses and ion-mobility fingerprints supported the treatment-dependent differentiation observed by mass spectrometry. Microwave and enzymatic pretreatments affected safflower seed oil through distinct compositional patterns, while their sequential application further influences the physicochemical properties and volatile constituents. These findings provide a basis for selecting pretreatment routes according to the desired chemical profile of safflower seed oil. Sensory evaluation and identification of odor-active compounds are still required before drawing conclusions about aroma quality or consumer acceptance.