Table 1. Aroma components of mealworms by different cooking methods

Aroma components	No.	RI¹⁾	Cas #	Relative peak area (mean±SD)²⁾				ID
Aroma components	No.	RI¹⁾	Cas #	Raw	Steaming	Roasting	Frying	ID
Pyrazines
2,6-Dimethyl-pyrazine	1	910	108-50-9	ND^b3)	ND^b	ND^b	0.283±0.029^a	MS/RI⁴⁾
2,5-Dimethyl-pyrazine	2	911	123-32-0	ND^b	ND^b	0.675±0.027^a	ND^b	MS/RI
2-Ethyl-5-methyl-pyrazine	3	1,001	13360-64-0	ND^b	ND^b	0.196±0.032^a	ND^b	MS/RI
2,3,5-Trimethyl-pyrazine	4	1,002	14667-55-1	ND^c	ND^c	0.157±0.015^b	0.238±0.008^a	MS/RI
Sum of pyrazines				0⁵⁾ (0%)⁶⁾	0 (0%)	1.028 (6.07%)	0.521 (3.44%)
Pyrrolidines
1-Butyl-pyrrolidine	5	895	767-10-2	ND^c	ND^c	0.220±0.019^b	0.296±0.042^a	MS
1-(2-Methyl-1-butenyl)-pyrrolidine	6	1,082	14091-87-3	ND^b	ND^b	ND^b	1.083±0.142^a	MS/RI
1-(1-Pentenyl)-pyrrolidine	7	1,128	13937-90-1	ND^b	ND^b	ND^b	0.071±0.012^a	MS
Sum of pyrrolidines				0	0	0.220 (1.30%)	1.450 (9.57%)
Aldehydes
Benzaldehyde	8	957	100-52-7	ND^b	0.012±0.001^b	0.292±0.021^a	ND^b	MS/RI
2-Phenylacetaldehyde	9	1,041	122-78-1	0.075±0.015^b	0.090±0.001^b	0.125±0.012^a	ND^c	MS/RI
4-Methyl-benzaldehyde	10	1,078	104-87-0	5.496±0.754^b	6.788±0.496^a	6.350±0.081^ab	4.289±0.805^c	MS/RI
Sum of aldehydes				5.571 (37.14%)	6.890 (39.37%)	6.767 (39.93%)	4.289 (28.28%)
Ketones
Heptan-2-one	11	892	110-43-0	ND^c	ND^c	0.077±0.013^b	0.188±0.021^a	MS/RI
Methylsulfonylmethane	12	923	67-71-0	0.033±0.005^bc	0.012±0.001^c	0.255±0.028^a	0.051±0.001^b	MS/RI
4-Methylheptan-2-one	13	939	6137-06-0	0.071±0.003^a	0.019±0.003^a	ND^b	ND^b	MS/RI
3,5-Dihydroxy-6-methyl-2,3-dihydropyran-4-one	14	1,139	28564-83-2	ND^b	0.069±0.010^a	ND^b	ND^b	MS/RI
1-(4-Acetylphenyl)-ethanone	15	1,431	1009-61-6	0.985±0.172^a	0.770±0.152^a	0.510±0.059^b	0.303±0.058^b	MS/RI
2,6-Ditert-butylcyclohexa-2,5-diene-1,4-dione	16	1,466	719-22-2	0.181±0.028^b	0.237±0.045^a	ND^c	ND^c	MS/RI
Sum of ketones				1.270 (8.11%)	1.107 (6.32%)	0.842 (4.97%)	0.542 (3.57%)
Alcohols
Pentan-1-ol	17	759	71-41-0	ND^b	ND^b	ND^b	0.193±0.019^a	MS/RI
2-Butoxyethanol	18	907	111-76-2	0.010±0.002^a	ND^b	ND^b	ND^b	MS/RI
Oct-1-en-3-ol	19	980	3391-86-4	ND^b	ND^b	0.102±0.015^a	ND^b	MS/RI
2,4-Bis(1,1-dimethylethyl)-phenol	20	1,511	96-76-4	0.580±0.109^a	0.487±0.093^a	0.153±0.024^b	0.100±0.017^b	MS/RI
Cadin-4-en-10-ol	21	1,655	481-34-5	0.025±0.005^a	ND^b	0.024±0.003^a	ND^b	MS/RI
Sum of alcohols				0.615 (4.10%)	0.487 (2.78%)	0.279 (1.65%)	0.293 (1.93%)
Esters & acid
Bis(2-methylpropyl)-hexanedioate	22	1,684	141-04-8	0.027±0.004^a	ND^b	ND^b	ND^b	MS/RI
Hexadecanoic acid	23	1,947	57-10-3	0.013±0.002^b	0.017±0.003^b	0.023±0.002^a	ND^c	MS/RI
Dibutly-benzene-1,2-dicarboxylate	24	1,960	84-74-2	0.041±0.011^a	0.015±0.002^b	0.019±0.002^b	ND^c	MS/RI
Sum of esters & acid				0.081 (0.55%)	0.032 (0.18%)	0.042 (0.25%)	0 (0%)
Hydrocarbons
Octane	25	797	111-65-9	0.263±0.046^c	0.341±0.029^c	0.481±0.081^b	0.602±0.079^a	MS/RI
Oct-2-ene	26	805	111-67-1	ND^b	ND^b	ND^b	0.063±0.009^a	MS/RI
2,4-Dimethyl-hept-1-ene	27	838	19549-87-2	0.948±0.164^b	1.073±0.076^ab	1.301±0.223^a	1.175±0.200^ab	MS/RI
2,3-Dimethyl-heptane	28	852	3074-71-3	0.016±0.003^a	ND^b	ND^b	ND^b	MS/RI
Ethyl-benzene	29	857	100-41-4	0.015±0.001^a	ND^b	ND^b	ND^b	MS/RI
4-Methyl-octane	30	861	2216-34-4	0.110±0.013^b	0.080±0.005^b	0.168±0.022^a	0.103±0.018^b	MS/RI
1,4-Xylene	31	865	106-42-3	0.034±0.004^b	0.034±0.005^b	0.037±0.004^b	0.062±0.010^a	MS/RI
2,4,6-Trimethyl-heptane	32	871	2613-61-8	ND^b	0.014±0.000^a	ND^b	ND^b	MS/RI
Nonane	33	899	111-84-2	0.018±0.001^b	0.022±0.002^a	ND^c	ND^c	MS/RI
4-Ethyl-octane	34	954	15869-86-0	0.012±0.001^b	0.014±0.001^a	ND^c	ND^c	MS/RI
4-Methyl-nonane	35	961	17301-94-9	0.086±0.008^a	0.102±0.006^a	ND^b	0.099±0.016^a	MS/RI
3-Methyl-nonane	36	970	5911-04-6	0.038±0.006^b	0.045±0.005^a	ND^c	ND^c	MS/RI
2,2,4,6,6-Pentamethyl-heptane	37	987	13475-82-6	0.097±0.014^a	0.114±0.020^a	0.114±0.021^a	ND^b	MS/RI
Decane	38	999	124-18-5	2.109±0.331^b	2.547±0.183^ab	2.563±0.161^ab	2.839±0.543^a	MS/RI
2,6-Dimethyl-nonane	39	1,012	17302-28-2	0.649±0.084^a	0.698±0.050^a	0.772±0.059^a	0.772±0.098^a	MS/RI
2,2,7,7-Tetramethyl-octane	40	1,023	1071-31-4	0.116±0.013^a	0.127±0.014^a	ND^b	ND^b	MS/RI
5-Ethyl-2,2,3-trimethyl-heptane	41	1,029	62199-06-8	0.147±0.010^a	0.070±0.005^b	ND^c	ND^c	MS
2,4-Dimethyl-dodecane	42	1,168	6117-99-3	ND^b	0.051±0.001^a	ND^b	ND^b	MS/RI
Dodecane	43	1,197	112-40-3	2.083±0.333^b	2.678±0.152^a	1.951±0.032^b	1.790±0.112^b	MS/RI
4,8-Dimethyl-undecane	44	1,212	17301-33-6	0.079±0.015^b	0.097±0.004^a	ND^c	ND^c	MS/RI
2,6,11-Trimethyl-dodecane	45	1,279	31295-56-4	ND^b	ND^b	ND^b	0.257±0.040^a	MS/RI
Tetradecane	46	1,398	629-59-4	0.697±0.030^a	0.879±0.175^a	0.377±0.066^b	0.306±0.058^b	MS/RI
Sum of hydrocarbons				7.517 (50.11%)	9.022 (51.34%)	7.764 (45.83%)	8.068 (53.20%)

Retention indices were determined using n-paraffins C₇–C₂₂ as external references.
Average of each peak area compared to that of the internal standard (n=3)±SD.
There are significant differences (p<0.05) among samples according to heating methods by using Duncan’s multiple comparison test between the samples having different letter in low.
MS, mass spectrum and retention index were consistent with those of an authentic compound; RI, mass spectrum and retention index were consistent with that of Wiley 7n and NIST17 mass spectrum database or manual interpretation (tentative identification).
Sum of each peak area compared to that of the internal standard (n=3).
Sum and their relative percentages of each peak areas according to chemical groups.
ND, not detected.