@article{scholars15706,
           pages = {375--388},
           title = {Characteristics and Empirical Modelling of Extract from Hibiscus sabdariffa Using Supercritical CO2 Extraction with Ethanol-Water as Modifier},
         journal = {Lecture Notes in Mechanical Engineering},
       publisher = {Springer Science and Business Media Deutschland GmbH},
             doi = {10.1007/978-981-16-0742-4{$_2$}{$_6$}},
            year = {2021},
            note = {cited By 1; Conference of 3rd International Conference on Separation Technology, ICoST 2020 ; Conference Date: 15 August 2020 Through 16 August 2020; Conference Code:261289},
             url = {https://www.scopus.com/inward/record.uri?eid=2-s2.0-85111357274&doi=10.1007\%2f978-981-16-0742-4\%5f26&partnerID=40&md5=e6c996cb9759345b712f3511d15cfc3d},
        keywords = {Anthocyanins; Color; Plant extracts; Regression analysis; Supercritical fluid extraction; Toxic materials, Characteristic model; Empirical model; Ethanol-water; Hibiscus sabdariffa; Natural red; Red color; S models; SC CO 2; Supercritical carbondioxides; Supercritical CO 2, Carbon dioxide},
        abstract = {The main constituents of the extract from Hibiscus sabdariffa calyces are anthocyanins which gave intense natural red colorant and commonly used for centuries for therapeutic purposes. Supercritical carbon dioxide (SC-CO2) technique could produce high-quality extracts from plant materials as it can exploit the non-toxic character and the gas{\^a}??liquid properties of the SC-CO2. This research aimed to characterise the colour and the pattern of Hibiscus sabdariffa SC-CO2 extraction. The colour was evaluated by using a CIELAB method meanwhile the presence of anthocyanins in the red colour extract was confirmed by High-Performance Liquid Chromatograph (HPLC). Two types of empirical models (Modified Brunner{\^a}??s and Esquivel{\^a}??s models) were used to describe the extracts obtained at series of operational parameters (i.e. pressure and temperature) at 7.5 and 10 of modifier ratio, with a total solvent flow rate of 4{\^A} ml/min. Both models were analysed using a non-linear regression method. The modified Brunner{\^a}??s model shows the best agreement between experimental and model calculated data with the lowest AARD of 1.30 at 70{\^A} {\^A}oC, 10{\^A} MPa, and 10 modifier ratio. {\^A}{\copyright} 2021, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.},
          author = {Idham, Z. and Putra, N. R. and Idrus, N. F. M. and Mili, N. and Ruslan, M. S. H. and Rasidek, N. A. M. and Yunus, M. A. C.},
            issn = {21954356},
            isbn = {9789811607417}
}