Journal of zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA Food Engineering 20 ( 1993) 12 1- 133 zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPO Extraction of Essential Oil of Black Pepper with Liquid Carbon Dioxide S. R. S. Ferreira, M. A. A. Meireles” & F. A. Cabral Departamento de Engenharia de Alimentos. Fat. Eng. Alim.. Unicamp. C.P. 6 I? 1. 1308 1 Campinas. S5o Paulo, Brazil (Received 4 February 1992; revised version received 1.5 June 1Y Y 2: accepted 6 July 1992 1 ABSTRACT Extraction of essential oil of black pepper was studied in a fixed bed extractor with liquid carbon dioxide as a solvent. The solubility of the oil in the solvent was determined, using the dynamic method. The solubilin of pepper oil varied from 0*07+0.01 to 0.10+0.04 for temperature ranging from 16 to 20°C and pressure from 6.35 to 735 MPa. The shape of the extraction curves indicates that about 90% of the oil was e.xtracted during the constant rate period. The results indicate that the subcritical essential oil extraction is a promising technology NOTATION N, Rate of extraction during the constant rate period (kg oil/s) t, Duration of the constant rate period (s) INTRODUCTION Supercritical fluid extraction of natural products can provide products completely free from toxic residues. Extraction of essential oils and oleoresins by using this technology may also provide higher quality products (Rizvi et al., 1986; Schultz & Randall, 1970). There are indica- tions that liquid carbon dioxide may be a good solvent for aroma extrac- tion (Francis, 1954; Schultz & Randall, 1970; Brogle, 1982; Germer 61 *To whom correspondence should be addressed. 121 Journal of Food Engineering 0260-8774/93/$06.00 - 0 1993 Elsevier Science Publishers Ltd, England. Printed in Great Britain