Characterization of binding ability of the commercial and novel feed binders in starch and protein based particles

Abstract

Pelletization aims to agglomerate a small particle of feed to become a larger particle using pressure, moisture, and heat. Pellets must have a basic form of physical quality in terms of hardness and durability to withstand the rigor of transportation. The objective of this work was to evaluate how spruce galactoglucomannan and its derivates may influence better binding ability between wheat-based particles (wheat flour, wheat starch and wheat protein concentrate). Also, to assess the acetylation level of the galactoglucomannan that function the best as a binder. Evaluating the effect of the galactoglucomannan on binding ability, guar gum (positive control (B5)) and lignoBond (negative control (B6)) were used as the reference binders. Diets were formulated with the feed binders at three different inclusion levels: 0.25%, 0.5% and 1.0%. Eighteen experimental diets were formulated with wheat flour, wheat starch, and wheat protein concentrates. Each experimental diet was made ten times. The pellets were made by using a single die pellet press method. Physical pellet quality parameter was analysed to determine the effect of the binders on p-max (N/mm2), tensile strength/hardness (N/mm), water activity (aw) and moisture content (%). The effect of the test diets was compared to the control diets for wheat flour, wheat starch and wheat protein concentrate. For wheat flour, the test binders (diet with B1, B2, B3, and B4) showed a similar effect on P-max (N/mm2) except B3 at level 0.25% and 0.5%. Again, P-max (N/mm2) from wheat starch and wheat protein concentrate were generally similar with the exception of B2, B3 and B6 at levels 0.5, 1.0 and 1.0% respectively. Further, on wheat flour, the water activity (aw) results showed that at least the values of the test binders fall within the range of the positive and negative control binders’ values. On wheat starch, at least one level of each of the binders had no significant effect compared to the control binders on water activity (aw). Though B2 at 0.25% and 0.5% recorded the highest water activity values. On the contrary to wheat protein concentrate, B3 affected water activity (aw) at all inclusion levels. Also, the p-values analysis showed that neither the binders nor the inclusion levels affected the tensile strength of wheat flour diet. For wheat starch, the analysis showed that the effect on tensile strength (N/mm) was the same among the binders except at B1, B2 and B3 at level 0.5% where a significant effect was observed compared to the others. Tensile strength (N/mm) from the wheat protein concentrate for the test binders were similar to both positive and negative controls except at B1 and B3 at 0.5% where a significant difference was observed with B6 at level 1.0%. The diets from wheat starch with B2 and B3 at all levels showed no significant effect on the moisture content compared to B5 and B6. The highest moisture content was observed at B4 level 1.0%, and it was significantly different from B5 and B6. For wheat flour, a significant effect on moisture content was observed only between B5 and B6 at level 1.0%. The wheat protein concentrate diets results showed no significant effect among the test binders (B1, B2, B3) and B5 at all levels except B3 at level 1.0% where a significant difference was observed. But a significant effect was observed among the levels of B1, B2, B3 and B6, except at level 1.0% and 0.5% where B3 and B6 respectively showed no effect. Treatment B4 at all levels showed a significant difference among both B5 and B6 at all levels except at B5 level 0.25%.