Subcritical butane extraction of oil and minor bioactive components from soybean germ: Determination of migration patterns and a kinetic model

Abstract

For the aim of determining the migration patterns and extraction kinetics of the oil and minor bioactive components during subcritical fluid extraction (SFE) process from soybean germ, the extraction efficiency was investigated at different temperature and time with butane as solvent. The results indicate that flaking treatment is beneficial to the release of soybean germ oil (SGO) and bioactive components. The chosen models (So and Macdonald's model for SGO, Baümler's model for bioactive components) were found to be in good agreement with the experimental data and could be used to explain the SGO and bioactive components migration during SFE process. Furthermore, the activation energy of phytosterols, tocopherols, and phospholipids were 13.42, 12.23, and 22.72 kJ/mol, respectively. In conclusion, high‐quality SGO that contain high levels of phytosterols (26.51 mg/g) and tocopherols (2.29 mg/g) and a lower content of phospholipids (26.68 mg/g) can be obtained with an extraction at 60 °C for 45 min. Practical applications In this study the effects of pretreatment of SG, solid/liquid ratio, extraction temperature and time on the yields of SGO and minor bioactive components were investigated. Simultaneously, the migration patterns and kinetic models of SGO and minor bioactive components described the subcritical butane extraction process accurately. Therefore, the research provided a theoretical support for the pretreatment of raw materials and the parameters control of subcritical extraction of soybean germ oil. The study can guide the popularization and application of subcritical fluid extraction for soybean germ oil extraction effectively. At present, the technology is ready for technical transformation in Henan subcritical fluid extraction company.

An Approach to the Application of a Modified Fick’s Diffusion Model: Development of an Algorithm

“…On the other hand, the systems analyzed by Inanc et al [26] and Sun et al [24] exhibited negative washing fractions, which do not have a physical meaning. The application of the calculation algorithm for the conditions described by these authors shows the need for up to 11 terms of the series for the data fitting, registering relative errors of up to 663.6 % in the predicted yield for ti.…”

“…The models applied by different authors were analyzed: Inanc et al [26], Sun et al [24], Najdanovic-Visak et al [20], Sá nchez et al [19], Colivet et al [16], Zá rate et al [11], Baümler et al [9], Amarante et al [10], Ferná ndez et al [8] and Pé rez et al [5].…”

“…In this context, given the nature of the solution to Fick's law (infinite series of terms) and the existence of boundary conditions, it is necessary to determine the criteria for the simplification and boundary conditions for a correct application of the model. This model has been used in the analysis of the extraction kinetics of oil from different matrices [5,[8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23] and of bioactive compounds from biological matrices [24][25]. Several authors [5, 8-9, 11, 17-19, 22-23] applied the mentioned model for study the kinetics of solvent extraction (hexane and ethanol) of vegetables oils, in a stirred batch device at constant temperature.…”

Extraction of Oat Lipids and Phospholipids Using Subcritical Propane and Dimethyl Ether: Experimental Data and Modeling

“…The alternative way of lipid extraction has become a research hotspot. Subcritical‐fluid extraction, which uses gases (gas pressed under subcritical conditions) as solvents, has been successfully used to separate lipids from wheat germ, [ 7 ] soybean germ, [ 8 ] egg yolk, [ 9 ] and oat bran. [ 10 ] The advantages of subcritical‐fluid extraction can be summarized as follows: 1) short extraction time and non‐requirement of solvent residues; [ 11 ] 2) reduced thermal degradation of bioactive compounds and low extraction temperature enabling the production of high‐quality extracts and meals; [ 12 ] 3) wide selection of solvents, such as propane and dimethyl ether (DME), which are usually selected for extracting lipophilic or hydrophilic compounds; [ 13,14 ] and 4) low cost for realizing industrial application given that subcritical‐fluid extraction requires only a small amount of solvents and mild pressures during extraction.…”

“…Sun et al. [ 8 ] found that the yield of phospholipids increased with increased extraction temperature when using subcritical butane for extracting soybean germ oil. Baümler et al.…”