Final answer:
To thicken a mixture with starch, first disperse the starch evenly, then heat it to allow the starch granules to dissolve and absorb water, and finally, continue heating until the mixture thickens. Cooling solidifies the gelatinized starch, resulting in the desired consistency.
Step-by-step explanation:
The three stages in the cooking process for starch thickeners are: dispersing, dissolving, and thickening. During the dispersing phase, the starch is evenly spread throughout the water or other liquid. Following this, in the dissolving phase, the starch granules absorb water and swell. This swelling is also known as gelatinization, which happens when heat is applied. Eventually, as cooking continues, the mixture thickens. Once the heat is removed and the preparation starts to cool, the starch thickener stabilizes and sets, which can be seen in foods like puddings and gravies. Throughout this process, the cooked food's consistency is significantly altered, and the thickened starch contributes to the overall texture of the dish.