KOREAN J. FOOD SCI. TECHNOL. Vol. 41, No. 6, pp. 603~608 (2009) y w w w» sƒ š ká Á½ * w w w y w The Korean Society of Food Science and Technology Analysis and Evaluation of Degrees of Contribution of Aroma Components in Hongro Apples Jin-Tae Koh, Young-Jae Yu, and Man-Goo Kim* Department of Environmental Science, Kangwon National University Abstract In this study, Hongro apples for test samples were selected from a market for aroma analysis. Analysis was done after 1 hr, in a forming headspace while maintaining a temperature of 25 o C. First, the complex aroma of the apples was assessed by a Direct Sensory Method. Secondly, the complex aroma was analyzed under individual aroma conditions separated by GC/FID/Olfactometry. Finally, aroma component analysis by GC/MS was performed. Degrees of contribution of aroma components were evaluated by an aroma value calculation considering aroma duration time, frequency, and intensity. The contribution rate (%) of the aroma induction component influencing apple aroma was determined by aroma component analysis and aroma contribution degree. As a result, it was found that the top four components were as follows, by contribution rate (%): acetic acid (23%), 1-hexanol (16%), butyl ethanoate (13%), 4-methoxy-2-methylbutane (9%). These four components constitute the complex aroma tested by the direct sensory method, and was largely recognized by the apple aroma test panel. Consequently, it was found that these components are the key factors in apple aroma. If the mechanism of formation of these components can be found, it could have a significant influence on consumers acceptance of new varieties of apples. Key words: apple aroma, GC/FID/Olfactometry, aroma value, GC/MS, aroma contribution degree ù š t z, ƒ ( ), Ÿ, ù, yy, y,,, y, Ÿ, y, 1988 z ã ƒwš y r r w w t Ë y ƒ š e wš w w (1). w» w 9 w. { w l ã. { l w» w solvent extraction(2,3), solvent-assisted flavor evaporation (SAFE)(4), simultaneous steam distillation-solvent extraction (SDE)(5), vacuum distillation(6), headspace solid phase microextraction(hs-spme) static(7) dynamic headspace *Corresponding author: Man-Goo Kim, Department of Environmental Science, Kangwon National University, Chunchon, Gangwon 200-701, Korea Tel: 82-33-250-8576 Fax: 82-33-251-3991 E-mail: mgkim@kangwon.ac.kr Received June 24, 2009; revised October 5, 2009; accepted October 6, 2009 (8,9), López (9) w w w dynamic headspace š w. w w (10-15) mw t 300 { yw š, yw w w x. š esters(78-92%), alcohols(6-10%), aldehydes, ketones, ethers 5ƒ. Mehinagic (11) w» w w ƒ š, w ƒ j w 15 ü. w mw t ù yw (11), ù» (12), y ù y»(16) w»ù, ö ƒ ƒ ù. t ù y w v w. w w sƒwš w» ³ w» w Kim (17) w d k»» w,w w w volatile organic compounds w, š(18), w»sƒ w w.» y wù sƒ w» w w» 0 5 ù d w. w w w» w w» sƒw». GC/FID/Olfactometry(GC/FID/O) olfactometry GC w k ƒy m FID 603
604 w t wz 41 «6y (2009) {» w» q w w. GC/FID/O w zƒ w»»»»ƒ w û w» w w» sƒƒ ƒ w. w m GC/FID/O w, ww» w w» sƒƒ ƒ w, w l rv mass flow controller(mfc) ew w x r w w» ù š, w w. ww» w» w ƒ w» txw w. ww» w GC/FID/O w»» k, 1 wý ý w y wš, 2 k ƒ»» mw y w kw, x ù š m y w x r ù w» w w» w» k w» w w» e y jš» sƒw ƒ w w. m š y w w. w»ƒ ù Áòw r (26.8 27.9 cm, Johnson, Thai Griptech Co. Ltd., Bangkok, Thailand) ü gj w z š ( : 99.999%) w 3z w w. w r š gj mw r œ» w z š ( : 99.999%) 700 ml š w s k 25 o C w x r x g 1 z w. w w w š s» w, w. 4 w»sƒ GC/FID/O w, 3 w w. w»sƒ GC/FID/O w w»sƒ œ x (19) w w. Table 1 œ x w»sƒ w» w w x. w»sƒ w w w» w k w w» 1-5 w g. Table 1 ùkü 4ƒ, q v, ¼ 14 cm, s 7mm 5 (3 : x, 2 : w»ƒ ù q v) w, 5 1 x w»ƒ ù 3 w»ƒ ù 2 wš, 3 x w» q wš w» 3, 4 w 4 sƒ w. gj wš š ( : 99.999%) 3z w r š 1 w w»sƒ gj š r ù w» d w. w»sƒ w w w w w» w»p» wš w w» w 0 5» w. -GC/FID/Olfactometry w w» w» w» w Younglin M600D GC capillary column(ua-1, 15 m 0.53 mm i.d. 0.5 µm, Frontier Lab, Fukushima, Japan) w x ƒ w w. Oven 40 o C 5 10 o C/min 80 o C¾ k. 15 o C/min 250 o C ¾ g š 10 z 31 ƒ. l 1 l rv e 500 ml mass flow controller(sierra Instruments, Inc., Monterey, CA, USA) w 50 ml/min 10 w. Fig. 1 -GC/FID/O. ew GC/FID, d ew odor detection port(odp) w»sƒ w» sƒw. d l e e Table 2. 1 10 w jš, ò 1 k š w GC 2. 2 ü GC column mw ƒ (retention time) ù. y» FID(flame ionization detector) ODP 5:1(2.5 ml/min:0.5 ml/min) ù. w»sƒ GC column l ù w» w ODP p w» w» ful» š w»sƒ w w» w» w w. Table 1. Test solution for selecting panels Test solution Concentration (wt%) Solvent Acetic acid 1.0 Distilled water Trimethylamine 0.1 Distilled water Methyl cyclopentanol 00.32 Paraffin β-penylethlyalcohol 1.0 Paraffin Fig. 1. Photograph of Cryofocusing-GC/FID/Olfactometry.
Table 2. Analytical conditions of Cryofocusing-GC/FID/Olfactometry y w» sƒ 605 Cryofocusing Coolant Liquid N 2 1st Loop (6.35 mm i.d.) sample focusing: 50 ml/min for 10 min 2nd Loop (0.80 mm i.d.) for 10 min Thermal desorption Temp. 100 o C boiling water Transferline temp.: 200 o C GC/FID/O Column UA-1 (15 m 0.53 mm i.d. 0.5, Frontier Lab) Column flow 3.0 ml/min (FID : ODP = 5 : 1) Oven temp. 40 o C (5 min)-10 o C/min-80 o C (0 min)-15 o C/min-250 o C (10 min) Injector temp. 200 o C FID temp. 250 o C Olfactometry Transferline temp.: 100 o C Assist gas Air: 300 ml/min, H 2 : 30 ml/min, make-up: 15 ml/min, He Humidified air 100 ml/min Table 3. Analytical conditions of GC/MS Table 4. Result of sensory evaluation method in apple GC/MS GCMS-QP2010 Panelists Aroma description Aroma intensity Column DB-1 (60 m 0.25 mm i.d. 0.25, J&W Scientific) Column flow 1.0 ml/min, He Oven temp. 40 o C (5 min)-10 o C/min-80 o C (0 min)-15 o C/min- 250 o C (20 min) Injector temp. 250 o C Ionization EI (70 ev) Scan range 35-400 m/z MS det. temp. ion source: 200 o C interface: 250 o C SPME-GC/MS GC/FID/O w w» y w» w SPME y w GC/MS(QP2010, Shimadzu, Kyoto, Japan) w. SPME y CAR/PDMS 75(Supelco Inc., Bellefonte, PA, USA) w. s œ 25 o C 1 x r x k z SPME y 10 jš, GC 250 o C 20 k g w. SPME-GC/MS Table 3. { w» w capillary column(db-1, 60 m 0.25 mm i.d. 0.25 µm, J&W Scientific, Folsom, CA, USA) w š x ƒ w w. 40 o C 5 z 10 o C/min 80 o C¾ g 15 o C/min 250 o C¾ g 20 40 ƒ. Ionization energy 70 ev š, mass range 35-400 amu.»» (retention time)» w vj xk retention index(ri) y w GC/FID/O w w w» w. w» w t library NIST107, NIST21, Willey7 w. š ww» d Table 4 w»sƒ 4 x r w» sƒw. 4 w»sƒ 2 w gw w, 2 w» A Apple, sweet, sour 2 B Apple, sour 2 C Apple, sweet and sour 3 D Apple, sweet 2 Aroma intensity 0 is none aroma, 1 is aroma threshold, 2 is moderate aroma, 3 is strong aroma, 4 is very strong aroma, 5 is over strong aroma sƒ 2 w w w. w ƒ ww» w» w» ww» y w p w» ƒ» ƒ w ƒ, w w w. GC/FID/Olfactometry w w» 4 w»sƒ w Fig. 2. A GC column l ù FID w {»yw ùkü š, B, C, D, E {» yw odor detection port mw w»sƒ w» w ùkü. GC/FID/O w w» w»p, w» Table 5 ùkü.»» w ƒ» GC/MS w» w RI y w ùkü. 31 39 {»yw FID w š w»sƒ 15 w» w. FID intensityƒ 1,000 mv w»ƒ, z û FID intensity w»ƒ š w w» ƒ ù w» w»ƒ ùkú. w w w FID w» sƒ w» w ƒ» ù. 15 w» sƒ 3 w w» RI 765 w», RI 858 w» e w», RI 871 tw», RI 912 gw w» w», RI 976 w», e w», j w w», RI 1204 ü k k
606 w t wz 41 «6y (2009) Fig. 2. FID chromatogram and ODP signal. A is FID signal of apple, and ODP signals of each panelist B, C, D and E. w» 6 ùkû, d w ww» gw w», w», w w» RI 765, 858, 912, 976 4 ww» ew, w». w w w w» w esters, alcohols, acids, ketones, ethers ùkû. Table 5 w» GC/FID/O ƒ š vj xk RI y w ùkü. ƒ w esters alcohols Dixon Hewett(10) šw w. w»sƒ 4 3 w w» w» ü similarity 96% 4-methoxy-2-methylbutane, w» e w» ü similarity 98% acetic acid, t w» ü similarity 96% 1-pentanol, w w» w» ü similarity 96% butyl ethanoate,, e, j w w» ü similarity 95% 1-hexanol, kk ý üƒ ù similarity 93% 2-methyl-butyl butanoate 6 ù kû. ww» ew, g, w w ü w ü similarity 96% 4-methoxy-2-methylbutane,, e w ü similarity 98% acetic acid,, w ü similarity 96% butyl ethanoate,, e,, gw w ü similarity 95% 1-hexanol, š w w» g w w» ü similarity 92% 3-buten-2-one 5ƒ. RI 818 š w ý ü, RI 1045 ý yw ùkû. Table 5 references (10-15) w t w. š aldehydes yw w w š ³ y. t w» ù ƒ, y aldehydes yw ƒ w w w w»sƒ ý w w š ƒ. š w 1-butanol, butyl ethanoate, 1-hexanol, butyl propionate, butyl butanoate, 2-methyl-butyl butanoate, hexyl propanoate, butyl hexanoate yw 8 4 š ew, ethyl ethanoate, 1-pentanol 2 ƒƒ 1 š e Table 5. Volatile components quantified in apple fruit by GC-MS, and aroma retention time (min), aroma hold time (min), aroma descriptors, aroma value and aroma intensity of emitted from apple fruit by GC/FID/Olfactometry No. GC/O RI 1) GC/MS RI 1) Component Aroma retention time (min) Aroma description No. of Aroma intensity SI4) panelists detected References 1 677 675 Ethyl ethanoate 0.04 Smell 1 95 1 (12) 2 703 2) 726 1-Butanol 0.03 Smell 1 96 1 (10, 12, 14, 15) 3 765 781 4-Methoxy-2-methylbutane 0.07 Apple-like 1 96 3 4 806 818 NPI 3) 0.07 Savory 1 1 5 825 835 3-Buten-2-one 0.18 Savory, sweet 1 92 1 6 858 865 Acetic acid 0.13 Apple-like, caramel 1 98 4 7 871 876 1-Pentanol 0.04 Grass 1 96 3 (14) 8 912 2) 913 Butyl ethanoate 0.10 Sweet, apple-like 1 96 3 (10-15) 9 976 970 1-Hexanol 0.09 Apple-like, caramel, sweet and sour 1 95 4 (10-12, 14, 15) 10 990 983 Butyl propionate 0.05 Plastic-like, fragrant 1 96 2 (10-13, 15) 11 1070 1045 NPI 3) 0.05 Smell 1 1 12 1131 1110 Butyl butanoate 0.04 Stench 1 98 2 (10-15) 13 1204 2) 1190 2-Methyl-butyl butanoate 0.04 Stale, burnt sugar 1 93 3 (10, 11, 14, 15) 14 1249 1238 Hexyl propanoate 0.05 Fusty 1 93 1 (10, 12-15) 15 1313 1308 Butyl hexanoate 0.07 Cinnamon-like 1 94 1 (10, 11, 13-15) 1) Retention Index 2) Not detected by FID 3) Not positively identified (NPI) 4) Similarity Index
w. w 4-methoxy-2-methylbutane, 3-buten-2-one, acetic acid 3ƒ šƒ yw ƒ. 3ƒ ƒƒ ether, ketone, acid yw ƒ ùkù w. zƒ w k w w» w w w» ƒ w š ƒ,»» w» ³ w». w» sƒ ƒƒ w ww» ù» w» w ƒ» sƒ w. w» s ƒw ƒƒ w» t xw» w GC/FID/O k w», w», w» w sƒ š w w» w. GC/FID/O w w»ƒƒ ww» ù» w» w T w» ùkü š, I w» Kim(20) w ww» w e ùkü» w w» w w. Aroma value T I 2 T: w» ( ) I: w» n: w»sƒ n ( ) 1 Fig. 3 GC/FID/O w w» (1) w» eyw w» wš, ƒ š x v ùkü. Acetic acidƒ 23% w»» ƒ š, 1-hexanol(16%), butyl butanoate(13%), 4- methoxy-2-methylbutane(9%) w»» ùkû. w w» 0.2 w» ƒ e ùkü. w»p, g, y w» sƒ 607 (1), e w» sƒw ww» ewš, GC/FID/O w»sƒ ƒ w w»» w. w ww» ùkù RI 876 t w»ƒ ù 1-pentanol RI 1190 ü k k w»ƒ ù 2-methyl-butyl butanoate w» w w»sƒ 3 w w» ù. w» w w»sƒ w» w, w ù ƒ w ww»» w w š ƒ. Esters yw yw w» eyw w» butyl butanoate w û w» ƒ. w» sƒ 23% w acetic acid 13% w butyl butanoate, 9% w 4-methoxy-2-methylbutane 3ƒ yw ww»» ùkü š yw. yw ƒ, esters yw y yw» sƒ ww»» w w w, w š w w w»ƒ w ù, w» w» k zƒ w k w w. w y k y w ww» y z GC/FID/O w w» w w»ƒ ù kù š GC/MS y w w w» ³ w»» sƒ z. w» w» ù p, ƒ» GC/FID/O w w w»,, w» w w» eyw w» w» w»» sƒƒ ƒ w, k y w ƒ w 4ƒ xü. Fig. 3. Pie chart of aroma contribution rate of each component of apple. 1) Not positively identified (NPI).
608 w t wz 41 «6y (2009) Esters yw 15 7 w w» k w» sƒ acetic acid(23%), 1-hexanol(16%), butyl ethanoate(13%), 2-methylbutyl butanoate(9%) 1 ester yw ww»» w, w š w w ww»» w. w 4ƒ 1-hexanol w ³, 3 ³ yw. ƒ ùkù w w k w» ƒ w š, w w» w. FIDù MS»»» w ³ w», Kim (17) w k w»» w w.» ƒ 4ƒ acetic acid(23%), 1- hexanol(16%), butyl ethanoate(13%), 2-methyl-butyl butanoate(9%) w ù gw w ww» y ew w», w» w»sƒ ƒ w w» w. 4ƒ ww» ƒ» w yw ƒ. yw f q w t w w w, w w w. w k w»» w w» eyw ùkü w» w sƒ» sƒ z, ù t w»» sƒw ƒ w». y w wš» s ƒw. m y kw x r x k z 25 C 1 w w o. w» ww» d wš, GC/FID/Olfactometry w w» w ww» w»ƒ y w GC/MS w w» w. w»» w» eyw» w w» w» š w w» w sƒw. w»» sƒ mw w w w»» (%) w.» (%) ƒ ùkù acetic acid(23%), 1-hexanol(16%), butyl ethanoate(13%), 2-methyl-butyl butanoate (9%) 4 ùkû. sƒ w ww» ew w»sƒ ƒ w w»» w. w w w. f q w t w w e w k. BK21 y q w.. 1. Kim JK, Seo HH. Causes of tree vigor weakening and occurrence of deformed fruit in Hongro apple trees. Korean J. Hort. Sci. Technol. 25: 408-412 (2007) 2. Wong NP, Parks OW. Simple technique for extracting flavor compounds from fatty foods. J. Dairy Sci. 51: 1768-1769 (1968) 3. Singleton VL. An extraction technique for recovery of flavors, pigments, and other constituents from wines and other aqueous solutions. Am. J. Enol. Viticult. 12: 1-8 (1961) 4. Xu Y, Fan W, Qian MC. Characterization of aroma compounds in apple cider using solvent-assisted flavor evaporation and headspace solid-phase microextraction. J. Agr. Food Chem. 55: 3051-3057 (2007) 5. Madruga MS. Elmore JS, Dodson AT, Mottram DS. Volatile flavour profile of goat meat extracted by three widely used techniques. Food Chem. 115: 1081-1087 (2009) 6. Forss D, Holloway G. Recovery of volatile compounds from butter oil. J. Am. Oil Chem. Soc. 44: 572-575 (1967) 7.Maeztu L, Sanz C, Andueza S, Paz De Pena M, Bello J, Cid C. Characterization of espresso coffee aroma by static headspace GC-MS and sensory flavor profile. J. Agr. Food Chem. 49: 5437-5444 (2001) 8. Elmore JS, Erbahadir MA, Mottram DS. Comparison of dynamic headspace concentration on tenax with solid phase microextraction for the analysis of aroma volatiles. J. Agr. Food Chem. 45: 2638-2641 (1997) 9. López ML, Lavilla MT, Riba M, Vendrell M. Comparison of volatile compounds in two seasons in apples: Golden Delicious and Granny Smith. J. Food Quality 21: 155-166 (1998) 10. Dixon J, Hewett EW. Factors affecting apple aroma/flavour volatile concentration: A review. New Zeal. J. Crop Hort. Sci. 28: 155-173 (2000) 11. Mehinagic E, Royer G, Symoneaux R, Jourjon F, Prost C. Characterization of odor-active volatiles in apples: influence of cultivars and maturity stage. J. Agr. Food Chem. 54: 2678-2687 (2006) 12. López ML, Lavilla MT, Recasens I, Graell J, Vendrell, M. Changes in aroma quality of Golden Delicious apples after storage at different oxygen and carbon dioxide concentrations. J. Sci. Food Agr. 80: 311-324 (2000) 13. Pudil F, Viden I, Velíšk J, Davidek J. The volatile components of an industrial apple aroma concentrate. Z. Lebensm. Unters. For. 177: 181-185 (1983) 14. Girard B, Lau OL. Effect of maturity and storage on quality and volatile production of Jonagold apples. Can. I. Food Sci. Tech. J. 28: 465-471 (1995) 15. Lurie S, Pre-Aymard C, Ravid U, Larkov O, Fallik, E. Effect of 1-methylcyclopropene on volatile emission and aroma in cv. Anna apples. J. Agr. Food Chem. 50: 4251-4256 (2002) 16. Hwang YS. After the apple harvest management and storage technologies for export. Vol. 195, pp. 48-68. IN: Korea Agricultural Trade Information. Korea Agro-Fisheries Trade Corporation, Seoul, Korea (2005) 17. Kim MG, Jung YR, Park JJ, Seo YM, Yoon IG. Evaluation metohd of odor-active compounds combine sensory method with instrumental analysis. Korean J. Odor Res. Eng. 1: 31-38 (2002) 18. Kim KH. A study on identification of odor active compounds emitted from an automobile air-conditioner evaporator. MS thesis, Kangwon National University, Gangwon, Korea (2007) 19. National Institute of Environmental Research. Standard method of odor compounds. Available from: http://www.nier.go.kr Accessed Nov. 25, 2009. 20. Kim SH. A study on identification and quantitation of individual odors forming a complex odor. MS thesis, Kangwon National University, Gangwon, Korea (2008) x