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1.
J Agric Food Chem ; 49(1): 118-23, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11305249

RESUMO

Crushing intensity and distillation time were evaluated for their effects on the oil yield and composition of steam-distilled essential oil from fruits of Coriandrum sativum var. microcarpum L. A comparison of oils produced by laboratory- and pilot-scale stills showed that the two still types gave comparable yields and oil composition. The laboratory still was then used to compare oil yields and compositions from fruits crushed at three different intensities, at intervals during a distillation period of 60 min. Both crushing intensity and distillation time had significant (P< 0.05) effects on the yield and composition of the oil. The maximum oil yield was less from the light-crushed fruits, but the rate of oil recovery was significantly P < 0.05) higher. From the light-crushed fruits, 95% of the maximum yield was extracted in 22.5 min compared with 32 and 39 min for the standard and heavy-crushed fruits, respectively. The effect of crushing intensity on oil composition was most pronounced on the low-boiling-point a-pinene and on the higher-boiling-point geranyl acetate. Crushing had little effect on linalool content, but distillation time could be manipulated to alter the linalool content of the oil.


Assuntos
Apiaceae/química , Manipulação de Alimentos , Monoterpenos , Óleos de Plantas/química , Monoterpenos Acíclicos , Monoterpenos Bicíclicos , Cromatografia Gasosa , Monoterpenos Cicloexânicos , Pressão , Vapor , Terpenos/análise
2.
J Agric Food Chem ; 47(5): 2048-54, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10552494

RESUMO

The factors affecting oil yield and quality of essential oils from Dalmatian sage (Salvia officinalis L.) are analyzed. Distillations of oils from individual plants and GC analyses revealed the presence of three chemotypes with different proportions of alpha- and beta-thujone (alpha/beta 10:1, 1.5:1, and 1:10). Different accessions could also be classified as having high (39-44%), medium (22-28%), or low (9%) total thujone contents. Flowering parts of S. officinalis had higher oil contents (1.6 versus 1.1%) and beta-pinene levels (27 versus 10%) than leaves and lower thujone levels (16 versus 31%). Major seasonal changes were found in the composition of oil distilled from a flowering type of Dalmatian sage, but oil yields from healthy, established plants did not vary greatly. Total thujone levels were lowest (25%) around flowering in spring and summer, so autumn or winter was the best harvest time to obtain oils with high thujone levels.


Assuntos
Lamiaceae/química , Magnoliopsida/química , Óleos Voláteis/análise , Geografia , Nova Zelândia , Estruturas Vegetais/química , Estações do Ano
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