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four CH 2 -groups present in the spectra of compounds containing CH 2 - long-chain higherfatty acids.Table 1. Lipid content after extraction of the material irradiated by microwave.№ Coffee residue,g.Microwaveirradiation, WTime ofirradiation,min.Raw materialfor extraction, gTime ofextraction, hProduct,g.1. 20 600 20 13.7527 2 1.50922. 20 450 20 16.4640 2 1.42763. 20 300 20 17.7204 2 1.5105Table 2. Lipid content after extraction of the dried material.№ Coffeeresidue, g.D. I. Yordanov, Z. B. Tsonev, T. V. Palichev, Z. A. Mustafa/Petroleum & Coal 55(2) 74-81, 2013 77Temperature ofdrying, CTime ofdrying, h.Raw material forextraction, gTime ofextraction, hProduct,g.1. 20 150 4 20 2 0.85772. 20 20 24 20 2 1.6805The results of gas chromatographic analysis of the lipid extracts are shown in Fig. 2-6.Based on the chromatograms above we were quantified the fatty acid composition of themethyl esters of fatty acids and neutral lipid classes. The data are presented in Table 3and 4.Table 3. A fatty acid composition of the total lipids.Name of fatty acidirradiated by450Wmicrowavefor 20 min.Lipid extract from coffee residue (%)irradiated by300Wmicrowavefor 20 min.dried at20 C for 24hours.dried at120-150 Cfor 4hours.600Wmicrowavefor 20 min.C14:0 (Myristic) 0.1 0.1 0.1 0.2 0.1C16:0 (Palmitic) 33.2 34.0 32.3 39.9 37.1C18:0 (Stearic) 7.6 7.9 6.9 9.9 8.5C9-18:1 (Oleic) 12.3 11.8 12.1 14.0 12.6C11-18:1 (Ricinoleic) 0.4 0.4 0.4 0.5 0.4C18:2 (Linoleic) 40.4 39.5 43.1 27.9 35.0C18:3(Linolenic) 0.7 0.7 0.8 0.1 0.4C20:0(Arachidic) 3.6 3.7 3.0 4.9 4.0C20:1 (Gadoleic) 0.4 0.5 0.4 0.5 0.4C21:0(Heneicosanoic) 0.1 0.1 0.1 0.2 0.1C22:0 (Beheric) 0.7 0.9 0.5 1.1 0.8C23:0 (Tricosanoic) 0.1 0.1 0.1 0.2 0.2C24:0 (Lignoceric) 0.4 0.3 0.2 0.6 0.4Table 4. The neutral lipid classes of the lipid extracts.Lipid classirradiatedby 450Wmicrowavefor 20 min.Lipid extract from coffee residue (%)irradiated by300Wmicrowavefor 20 min.dried at20 C for 24hours.dried at120-150 Cfor 4 hours.irradiated by600Wmicrowavefor 20 min.sterol esters 5.2 5.8 5.2 5.6 4.9triacylglycerols 65.7 65.4 67.1 46.8 56.0non identifiedlipid zoneSterols +diacylglycerols + freefatty acidsmonoacylglycerols +Polar lipids5.0 3.8 7.5 8.4 4.216.8 18.2 15.7 24.3 23.77.3 6.84.514.9 11.2
CountsCountsCountsD. I. Yordanov, Z. B. Tsonev, T. V. Palichev, Z. A. Mustafa/Petroleum & Coal 55(2) 74-81, 2013 78The data for the quantitative interpretation of the fatty acid composition classes and neutrallipids are presented at the figures 7-8.Fig. 1. IR spectra of lipid extract, obtained by n-hexane extraction of the coffee residuefrom vending-automat.D:\Analytical\...\ME-Bs-2_111222120129 22.12.2011 г. 12:01:29RT: 0.31 - 37.99850000008000000075000000700000006500000060000000550000005000000015.3419.51450000004000000035000000300000002500000018.8020000000150000001000000050000000.8106.1410.25 12.1318.4622.1116.09 22.56 27.18 30.62 34.945 10 15 20 25 30 35Time (min)Fig. 2. GC chromatogram of the lipid extractfrom coffee residue irradiated by 450W microwavefor 20 minutesFig. 3. GC chromatogram of the lipid extractfrom coffee residue irradiated by 300W microwavefor 20 minutesD:\Analytical\...\Me-Bs-3_111222145118 22.12.2011 г. 14:51:18D:\Analytical\...\Me-Bs-4_111222153316 22.12.2011 г. 15:33:16RT: 0.36 - 38.00100000000950000009000000085000000800000007500000070000000NL:1.34E8FIDAnalogME-Bs-2_111222120129RT: 0.41 - 37.99NL:1.34E8FID 90000000AnalogMe-Bs- 850000003_111222145118 80000000750000007000000065000000NL:1.34E8FIDAnalogMe-Bs-4_11122215331665000000600000005500000015.3419.5260000000550000005000000015.35500000004500000040000000350000003000000025000000200000001500000010000000500000000.604.525.6718.8118.4722.1010.25 12.12 16.09 22.55 27.16 30.59 34.905 10 15 20 25 30 35Time (min)Fig. 4. GC chromatogram of the lipid extractfrom coffee residue dried at 20 C for 24 hours4500000040000000350000003000000025000000200000001500000010000000500000000.8218.8118.4719.4922.1222.56 27.185.67 7.07 10.26 12.13 16.0930.61 34.935 10 15 20 25 30 35Time (min)Fig. 5. GC chromatogram of the lipid extractfrom coffee residue dried at 120-150 C for 4 hours
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