Nitrogen- free extracts or NFE is a vital part of animal feed assessment. This is part of a proximate analysis and is the only component that is not analyzed and calculated. Contrary to the name, this analysis does not pertain to nitrogen and focuses on sugar and starch content in animal feed. There is an equation used to measure NFE and it can be measured starting with 100 and subtracting the sum of the basic protein, fat, water, ash and fiber from 100. This is important in aquaponics.
In aquaponics, the waste produced by fish becomes the nutrients absorbed by the food it helps produce. As a result, the feed analysis is vital in determining what is consumed by the farmed fish, which ultimately becomes a factor in aquaponics plant growth.
Several studies have looked into the ratio of NFE to other feed components. While some of these studies have shown desirable results, none of the studies indicate that solely the NFE ratio is detrimental to aquaponics and it is more of a combination effect. NFE is definitely a key component of feed analysis, the exact contribution it has is still inconclusive. Companies like Monsanto have conducted tests on this with inconclusive finds, largely due to sample size and control factors.