Influence of origin of the bean on the chemical composition, particle size, and color of soybean meal.

Abstract

A total of 79 soybean meal (SBM) samples from Argentina (ARG; n = 44), Brazil (BRA; n = 18), and USA (n = 17) were collected for 2 consecutive years at arrival of the vessel to European ports to study the effects of soybean origin on the chemical composition (DM, ash, CP, amino acid profile by NIR, EE, CF, NDF, sucrose, raffinose, stachyose, and, macro and trace minerals) and protein quality variables [KOH solubility (%), protein dispersability (PDI, %), urease activity (UA, mg N/g), trypsin inhibitor activity (TIA, mg/g DM), and heat damage index (HDI)]. In addition the particle size distribution and the geometric mean diameter ± Log normal SD (GMD ± GSD) and color [lightness (L*), redness (a*), and yellowness (b*)] of the samples was determined. Data were analyzed using the Mixed procedure of SAS with origin of the beans as main factor. On DM basis, ash content was higher for the ARG meals than in the USA meals with BRA meals being intermediate (P < 0.05). Brazilian meals had more protein than ARG and USA meals (P < 0.01). EE content was higher for the USA meals than for the ARG meals with BRA meals being intermediate (P < 0.05). Crude fiber was not affected by the origin of the meals, in spite of the higher CP content of the BRA meals. Stachyose and sucrose were higher (P < 0.001) for the USA meals than for the BRA and ARG meals. The K content was higher (P < 0.001) for ARG meals than for the BRA and USA meals, whereas Fe content was higher (P < 0.001) in BRA meals than in ARG and USA meals. USA meals had more Arg, Lys, Met+Cys, and Trp per unit of protein (% CP) than BRA meals (P < 0.01) with ARG SBM being usually in an intermediate position. As a result, the percentage of the 5 critical AA in the protein fraction was higher for the USA meals than for BRA meals. PDI, KOH, and TIA values were higher for the USA and BRA meals than for the ARG meals (P < 0.001). Heat damage index, a measurement of Maillard reactions, was lower for the USA meals than for the ARG meals, and lower both than for the BRA meals. Brazilian meals had higher GMD (P < 0.001) than the ARG and USA meals. USA meals had greater L* and lower a* values (P < 0.001) than BRA meals. In summary, chemical composition, protein quality, particle size, and color of the meals varied widely with the origin of the beans, which may affect the protein quality and nutritive value of SBM depending on soybean origin.