Soybean meal (SBM) is the most used source of protein in animal feeding. In this first article of a series of three, the authors review composition and nutrtional value for different species, as well as factors determining their variability.
Introduction
Soybean meal (SBM) is the main source of protein and amino acids (AA) used in animal feed formulations worldwide, particularly for monogastric species. Soybean is a source of high-quality vegetable protein, with a less variable chemical composition than other protein sources. However, due to its high inclusion rates (especially in poultry diets), any lack of uniformity in SBM will have more relevance than a variation in any of the other protein sources added to the formula.
In numerous practical situations, the quality control of soybean meal and derivatives is limited to analyses of moisture, crude fibre, crude protein (CP), and urease activity.
Analysing only moisture, crude fibre, crude protein (CP), and urease activity is not enough to accurately determine soybean nutritional value.
Other parameters such as sugar content, NDF, AA profile and variables like trypsin inhibitors (TI), Maillard reactions and KOH protein solubility are rarely examined.
All these parameters are relevant. They allow us to properly evaluate the nutritional value of the ingredient. However, these variables are subjected to variations depending on:
seed genotype
type of soil and environmental conditions during growth (Westgate et al., 2000)
processing characteristics (Grieshop et al., 2003)
duration of storage (Serrano et al., 2013)
presence of antinutritional factors (Karr-Lilienthal et al., 2004; Frikha et al. 2012)
country of origin of the beans (Ravindran et al., 2014; García Rebollar et al., 2014 y 2016).
SBM accounts for the main cost of raw materials in a feed mill.
There is a need to improve the methods currently used for soybean quality control. Most soybean quality control programs focus on the determination of protein content, but not much on the energy value, which reduces their practical relevance.
The objective of present study consists of three parts:
Identify the main factors affecting the profile and nutritional quality of SBM.
Define and evaluate the different methodologies used to estimate SBM value and determine possible improvements in quality control in the feed industry.
Describe the different types of soybean according to its origin.
Nutritional value
What are the existing products...