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Basil, garlic, and ginger essential oil were extracted by steam
distillation, and analyzed by GC and GC-ms. The major components of basil
essential oil were methyl chavicol (about 86%) and 1, 8-cineole (6%);
those of garlic essential oil were diallyl disulfide (39%) and diallyl
trisulfide (31%) etc.; and those of ginger essential oil were camphene
(16%) and geranial (19%) etc.. In terms of charater-impact compounds,
methyl chavicol which gave fragrance, sweet, fresh, and minty, and
1-octen-3-o1 which gave unpleasant strongly green odor existed in the
basil essential oil. Diallyl disulfide which gave strongly pungent
garlic-like aroma existed in the garlic essential oil. Neral which gave
fragrance, sweet, fresh, cooling, and woody aroma, and those of genarial
and beta-sesquiphellandrene + ar-curcumene + genaryl acetate which gave
pungent and warm odor existed in the ginger essential oil. In addition,
six different kinds of basil essential oils were analyzed by sensory
evaluation and gaschromatography. Furthermore, the data were calculated
by SAS stepwise regression method trying to find a regression equation
which could be used as an estimation for the quality of basil essential
oil.
Microcapsules of basil, garlic, and ginger essential oil were
prepared by spray drying. Changes of components of essential oils during
spray-drying process were found. For instance, among the percentage
compositions of basil essential oil methyl chayicol etc. tended to
decrease, while linalool and 1, 8-cineole etc. increasing. In garlic
essential oil, the percentage compositions of diallyl sulfide, methyl
allyl disulfide, diallyl disulfide, and 2-vinyl-4H-1, 3-dithiin tended to
decrease, while methyl allyl trisulfide and diallyl trisulfide increasing.
In ginger essential oil, the percentage compositions of alphapinene,
camphene, myrcene, limonene, beta-phellandrene, and geranial tended to
decrease, while 1, 8-cineole, 2-heptanol + 6-methyl-5-hepten-2-one,
linalool and zingiberene increasing. In respect of the properties of
microcapsules which added amounts of core materials were different, the
oil retentions decreased with increasing the added amounts of core
materials, and the amounts of surface oil were about 0.4-1.7% of oil
retentions. The particle size and flowability of microcapusles increased
with increasing the added amounts of core materials, and there were no
significantly difference for the surface structures of micro-capsules. On
the other hand, changes of essential oils fo microcapsules which were
stored for one year at room temperature were also investigated. The
results of gaschromatography and sensory evaluation showed that the
gtarlic essential oil was the most stable followed by basil and ginger
essential oil, respectively.
Corn and waxy maize native starches were modified by acetylation or
phosphation. The high and low degree of substitutions (D.S.) for
acetylations were around 0.14-0.18 and 0.5-0.54, respectively; while those
for phosphations were about 0.01 and 0.12, respectively. The structures
of native starches were damaged during the modifications, the higher
degree of modification the more damage was. The starch damage of high
D.S. of phosphation, especially high, was about 55-62%, The gelatini-
zation temperature and enthalphy of modified starches lowered 15-18 0c and
3-12 j/g starch, respectively, compared with native starches. The
modified starches of high D.S. of phosphation even formed cold water
soluble starches. Generally, the emulsufying properties, which are
important to the preparation of microcapsules, of modified starches
mentioned above were better than those of native starches.
The properties of microcapusles, which prepared from using corn and
waxy maize native and modified starches stated above as carriers and basil
essential oil as core material, were studied. The oil retentions were
around 90% when corn modified starch of high D.S. of phosphation and waxy
maize modified starches of low D.S. of acetylation and phosphation were
used as carriers. The surface oils were around 0.22-0.58% of oil
retentions. The effects of substituted groups on the percentage
compositions of basil essential oil of microcapsules were also
investigated. For example, there were higher percentage compositions of
esters and 1, 8-cineole in basil essential oil when using acetylated
modified starches as carrier. In respect of surface structure of micro-
capsules, different carrier had its own characteristics according to the
results from SEM. For instance, corn native starch as carrier gave deeply
dent but smooth surface structure similar to those of phosphated modified
starches. However, waxy maize native starch as carrier gave slightly dent
and more crinkly surface structure similar to those of acetylated modified
starches.
In order to improve the flowability and dissolution ability of
spray-dried microcapsules, agglomerated microcapsules were prepared by
combination of spray drying and agglomeration techniques using different
concentrations of flycerol aqueous solutions as binding agent. According
to the results, the optimum concentration of binding agent was 30%. This
level gave the agglomerated microcapsules outstanding dissolution ability
in water compared to that of the control. The average particle size was
2-3 times as large in the agglomerated sample greater than that of the
control. Also the flow rate of the sample was 130 times than that of the
control.
以水蒸氣餾法分別萃取羅勒、蒜、薑之精油，經由氣相層析儀與氣相層析儀一質譜儀
之分析鑑定，得知羅勒精油之主成分為methyl chavicol ( 約86％) 與1,8-ci-meole
( 約6％)；蒜精油為diallyl disulfide(約39％),deallyl trisulfide( 約31％)
等；而薑精油則為camphene(約16％),geramial(
約19％) 等。至於在精油成分之味道貢獻方面，羅勒精油中，methyl cha-vicol與1-
octen-3-o1均為特徵化合物，methyl cha-vicol帶有香味，甜味，清涼薄荷味等好的
羅勒味道，而l-octen-3-o1則賦予令人不悅的青草味，惟此一成分僅在於羅勒梗精油
中含量較多，因此對於整株羅勒精油的味道並不會產生太大的影響；在蒜精油中，以
diallyl
di-sulfide對於香味貢獻最大，具有非常強的蒜刺鼻味；在薑精油中，則以 neral,g
eranial,beta-sesquiphel-landrene＋ar-curcumene ＋geranyl acetate 等成分對
於香味最有頁獻，neral 具有香味，甜味，清涼味與木材味等，而geranial與beta-s
esquiphellandrene ＋ar-curcumene＋geranyl acetate 具有刺鼻與溫暖的味道。另
外，就羅勒精油之品質而言，採用品評與氣相層析之分析方法，針對六種不同植體部
位與不同處理之精油進行研究，並配合逐步迴歸之統計方法，求得一條迴歸方程式，
用以作為羅勒精油品管的標準．
以噴霧乾燥法製備羅勒，蒜，薑精油徵膠囊，發現在噴霧乾燥過程中有精油成分變化
的現象。例如羅勒精油成分百分組成中之methyl chavicol 等則有增加的傾向；蒜精
油成分中diallyl sulfide ,methyl allyl disulfide,diallyl
disulfide,2-vinyl-4H-1,3-dithiin等減少,而methyl allyl trisulfide
與diallyl
trisulfide增加；薑精油中之alpha-phellandrene,camphene,myrcene,limoneme
,beta-phellandrene,geranial等減少，而1，8-cineole,2-heptanol
＋6-methyl-5-hepten-2-one,linalool,zingiberene等增加。至於在各種不同精油
添加量之微膠囊性狀方面，微膠囊之精油保留率隨精油添加量增加而降低，而表面油
為保留量之0.4∼1.7％左右。微膠囊之粒度與流動性則隨著精油添加量之增加而增加
，但不同精油添加量之微膠囊之表面構造並無顯著性差異。另外，精油微膠囊在室溫
下貯藏一年後，其精油成分有所變化，由氣相層析與品評結果顯示，蒜精油成分變化
最小，羅勒精油次之，而以薑精油變化最大．
將天然玉米與糯玉米澱粉以醋酸或磷酸修飾後，醋酸低、高取代度則分別為0.14與∼
0.54左右，而磷酸低、高取代度則分別為0.01與0.1∼0.12左右。經過修飾之澱粉，
其天然澱粉結構遭受破壞，隨著修飾程度愈高，破壞度愈大，尤以磷酸高取代修飾澱
粉之破壞率更高達55∼62％左右；糊化溫度與糊化所需熱能則分別下降15∼18℃與3
∼12焦耳／克澱粉，甚至形成冷水可溶澱粉。一般而言，醋酸或磷酸修飾澱粉之乳化
性質較天然者為佳，而此等性質對於微膠囊之製備相當重要．
以玉米、糯玉米之天然及醋酸與磷酸修飾澱粉進行羅勒精油微膠囊之製備。精油保留
量以玉米磷酸高取代修飾澱粉，糯玉米醋酸低取代與磷酸代取代修飾澱粉為膠囊壁物
質時較佳，約為90％左右；而表面油一般為保留量之0.22∼0.58％左右。由各種膠囊
壁中之羅勒精油組成結果可以發現，膠囊壁物質之取代基不同，其所保留之精油組成
亦有所差異。例如以醋酸修飾澱粉為膠囊壁物質時，其所保留之精油成分組成中，以
酯類與1,8-cineole 之量較高。至於在微膠囊之表面構造方面，結果顯示各種不同膠
囊壁物質所製得之微膠囊，其表面構造各具特色。例如玉米天然澱粉者具有凹陷而光
滑的表面特徵，與磷酸修飾澱粉者較為相似；而糯玉米天然澱粉者，其表面凹陷較淺
，呈現出皺折較多的特徵，與醋酸修飾澱粉者較為相似．
為了改進噴霧乾燥精油微膠囊之流動性與速溶性，以不同濃度之甘油水溶液作為黏著
劑，採用造粒技術配合噴霧乾燥技術，製備造粒微膠囊。結果顯示以30％甘油水溶液
為黏著劑時之造粒微膠囊具有最佳性狀，其表現出優越的溶出速率，而平均粒徑是對
照組的2∼3倍，且流動速率是對照組的130倍．
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