Corn, average composition

Ans. The composition is an average composition. Corn oil like all fats and oils is a mixture of many different complex triacylglycerols. There are some triacylglycerol molecules that contain two linoleic units and one oleic unit, some that contain one each of linoleic, oleic, and palmitic, some that contain one each of linoleic, oleic, and stearic, and so on. 

Corn stover was harvested from south Hungary in the fall of 2001. The selected and washed straw was air-dried to an average 90% dry matter (DM) content. The air-dried material was ground and sieved, and the fraction with a particle size of 2-5 mm was used. The composition of this material and also the washed, solid fibrous fraction remaining after pretreatment was determined using Kaar s (19) method. To measure the total ash content, approx 0.5 g of dried sample was placed in a crucible, ignited at 550°C for 3 h, cooled in a desiccator, and weighed. 

A total of 196 composite milk samples from seven Holstein cows have been analyzed (20). The samples have been collected for 28 days, consecutively, beginning on the seventh day after calving. Cows were fed a ration containing corn silage, Timothy hay, commercial concentrate mixture (corn, barley, alfalfa meal, beet pulp, and CaCOs), trace minerals, and vitamins premix, and soybean meal provided 48% of total CP of the diet. The average BW of the cows was 552 kg. Animals were fed twice daily ad libitum and always had access to drinking water. Three of the examined cows had been healthy, with SCC lower than 137,000 cells/ml. One cow had been mastitic during the entire experimental period—the measured SCC varied from 204,000 to 11,876,000 cells/ml. Three cows had mastitic and healthy periods (SCC between 80,000 and 4,737,000 cells/ml). 

Figure L The change in weight-average molecular weight and the carbohydrate composition over an extended time period during acetylation of corn fiber arabinoxylan using 0.65 wt% MSA at 25 °C. Reproduced with permission from reference 19. Copyright 2002 Elsevier Science Ltd.

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