It was reported that addition of soybean oil results the variations of on line parameters,such as ECO 2,EO 2,CER,OUR,DO,RQ,K La and so on,during the fermentation and their co relation was analyzed in this paper.It has show that:first,the function of soybean oil were different at different phases of fermentation through parameter co relative analysis,namely soybean oil was an anti foam regent and a carbon resource substrate at the middle phase of fermentation,while the oil was only an anti foam regent at the final phase.Second,the uses of metabolic substrates will be changed when the soybean oil was a carbone resource to some extent that was related with the carbon resource restriction and cell′s activity.Third,the affection factors at balance of oxygen can be realized to optimize the soybean oil feed through parameter co relative analysis.
