Increasing the Digestive Efficiency of Local Raw Materials with Enzymes PART 2
Evaluating The Nutritional Value of an Alternative is Key
Prior to inclusion in a new feed formulation, an alternative raw material must be evaluated for its: nutritional value, safety, palatability, processing quality, economic feasibility, environmental impact, and availability. Assessing nutritional value is key because most processed raw materials and co-products contain higher levels of the anti-nutrient phytate, fibre, and indigestible protein than the parent grain or oil-seed.
How Can Enzymes Help?
Clearly, the concept of using exogenous enzymes to improve feed digestibility by breaking down target substrates into simpler, more absorbable, forms is not new. What is new is the strategy of using enzymes to support increased inclusion of alternative ingredients in a more precision nutrition-based approach.
In this context, enzymes can:
1. Enable the use of cheaper and/or more locally available ingredients at a higher inclusion rate in the diet, without compromising on production outcomes.
2. Reduce reliance on food-grade ingredients through increased use of co-products that supports the concept of a circular economy in which losses are minimized and sustainability is improved.
3. Compensate for variation in ingredient quality by adjusting the enzyme dose
NIR Analytical Technologies
Near-infrared (NIR) spectroscopy technologies can be particularly useful in this sphere. NIR analytics are being used to rapidly and accurately assess the detailed nutritional composition of alternative (and conventional) ingredients. The technology allows quantification of a broader range of nutritional analytes than traditional methods, including phytate-phosphorus, total, soluble and insoluble dietary fibre, individual non-starch polysaccharides (NSP), resistant, readily and slowly digestible starch and indigestible protein and amino acids. It also enables variability in composition to be quantified.
Outputs can be used to map the availability of specific substrates (phytate, carbohydrates, protein, amino acids) against available enzymes (phytases, carbohydrases and protease) and to optimize the feed formulation accordingly.
Digestibility Improvement Factors (DIF)
Many leading enterprises in the industry have adopted the concept of digestibility improvement factors (DIF) to the (quantifiable) increase in nutrient utilization by the animal that is expected from the addition of specified enzymes at specified dose levels in a diet of known composition.
The DIF takes account of the enzyme’s precise effect on individual raw materials and their particular composition and substrate characteristics (e.g. the content of NSP arabinoxylans in a particular variety of wheat). Hence, this approach differs fundamentally from the approach of using enzymes in feed, which confers a much more uncertain response. Work is ongoing to develop the supporting algorithms for using DIF to optimizing fibre digestibility in enzyme-supplemented diets.
