Dry-milled com germ

Christianson, D.D. et al. Supercritical fluid extraction of dry-milled com germ with carbon dioxide, J. Food Sci., 49, 229,1984. 

Oil extraction yield was not affected by moisture content in soybean (3-12%) [3] and dry-milled com germ (3.5-8%) [4]. Co-extraction of water was observed only during the final stages of extraction since oil is more soluble than water in SC-CO2 [1,5]. However, the amount of water in the oil extracts was not quantified. When Snyder et al. [3]... 

In any case, Figure 2b indicates that the extraction at the lowest pressure (Run 6, 21 MPa) is very slow, which may be due to the low solubility of seed oil in SC-CO2. An increase of oil solubility when extraction pressure is increased has been also reported for dry-milled com germ (Christianson et al., 1984) and other seed oils (Friedrich and Pryde, 1984). As it will be explained later in this chapter, the first part of the extraction can be considered to be controlled by this thermodynamic parameter. 

Christianson, D. D., J. P. Friedrich, G. R. List, K. Warner, E. B. Bagley, A. C. Stringfellow, and G. E. Inglett (1984). Supercritical Fluid Extraction of dry-milled com germ with carbon dioxide. Journal of Food Science 49, 229-232. 

Oil is usually obtained from dry milled corn germ by full press (via an expeller). List and co-workers (1984) compared some of the chemical components in com oil from wet milled germ versus dry milled germ and reported lower levels of free fatty acids, lower levels of phosphorus, and higher levels of tocopherols in the latter. 

One of the first studies about SFE of com germ oil was performed by the Agricultural Research Service of the United States Department of Agriculture (Peoria, Illinois). List et al., (List et al., 1984, List and Friedrich, 1989) and Christianson et al., (Christianson et al., 1984) compared the quality of cmde oils obtained from dry and wet milled com germ using SFE at 50-90°C and 55-83 MPa and conventional extraction methods. They concluded that the oil obtained by SC-CO2 extraction exhibited lower refining loss and lighter color. 

Although FFA content of the oil varies considerably depending on the preharvest and postharvest conditions, it is usually in the range of 1-1.5% of the total acyl lipids. Wet milled corn germ oil contains higher FFA content than that of the dry milled oil, 1.5 % and about 2%, respectively (7, 66). The PL content of com germ oil varies with the extraction process. Expelled oil contains about 120 ppm PL as compared with 670 ppm in hexane prepress commercial products (66). 

Com Germ, Dry Milling processes com germ that has been separated from the other com components using a dry process of mechanical chafing and air sifting 0.7 0.7... 

Weller, C.L., Paulsen, M.R., and Mbuvi, S. 1989. Germ weight, germ oil content, and estimated oil yield for wet-milled yellow dent com as affected by moisture content at harvest and temperature of drying air. Cereal Chem. 66, 273-275. 

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