The effect of dietary fibre inclusion on milk coagulation kinetics

The objective of this study was to determine the effects of soluble dietary fibre inclusion on milk coagulation kinetics. Three fibre ingredients gum acacia, inulin or pectin were added to milk prior to addition of rennet. Milk coagulation was monitored using a controlled stress rheometer, NIR transmission sensor and a hot wire sensor. Gel times and coagulum firming rates were determined from the sensor response characteristics. Gel microstructure was examined using confocal scanning laser microscopy. Gum acacia (1–3% (w/w)) significantly decreased gel times and coagulum firming times and these gels had more open casein networks than the control gels. A 2% (w/w) addition of inulin was required to decrease gel time and coagulum firming time and no discernable difference was observed between the inulin enriched and control gels. Pectin (0.2–0.4% (w/w)) significantly reduced gel times. Above 0.2% (w/w), added pectin increased coagulum firming times and resulted in a limited casein network developing.