2. Binding Amylose works better than amylopectin at holding batters to vegetables and meats during deep frying Allow batter dipped foods to set for 20 minutes before frying for better binding Carageenan is a gum that is used as a binding agent in dairy. For example, it is used in cocoa to prevent chocolate milk from settling.

3. Thickening During heating, molecules of starch are stretched. As they swell and take up water causing thickening Gelatinization – thickening a liquid with starch. Starch used in instant puddings has been pregelatinized, allowing it to gel at the temperature of cold milk

3. Thickening Continued… The presence of salt and sugar will interfere with starch’s ability to thicken When sugar is combined with flour or any other starch, it will decrease the strength & viscosity of the gel. Depending on the starch, salt can increase or decrease thickening

4. Stabilizing All complex carbohydrates help stabilize food products by keeping ingredients evenly distributed throughout mixtures

Types of Starch and Liquid Mixtures Slurries – uncooked mixtures of water and starch which is used to thicken soups or sauces Sols – thickened liquids. Examples: pancake/waffle/muffin batter. Pastes – thickened mixtures of starch and liquid that have very little flow. Also used to thicken soups & stews. Gels – starch mixtures that are rigid

Physical Properties of Starch & Liquid Mixtures 5 properties food scientists evaluate before selecting a starch, which can affect flavor and consistency. Retrogradation Viscosity Stability Opacity versus Translucency Texture

1. Retrogradation Retrogadation – firming of a gel during cooling and standing. Changes in retrogradation cracks form in the gel water leaks from the gel over time (syneresis) Syneresis example: mustard with the liquid separated out

2. Viscosity Viscosity - Resistance of a mixture to flow Varies with molecular size, shape, and charge. Larger molecules are harder to move. Linear molecules are more viscous than branched. Charged particles have more resistance to flow. Gels are more viscous than pastes, pastes are more viscous than sols Food scientists compare starch viscosity to easily see how substituting one starch for another will affect the product

3. Stability Stability – ability of a thickened mixture to remain constant over time and temperature changes. Cornstarch has more thickening power than flour, BUT it is not as stable. Cornstarch gravies will not reheat to a thin smooth sauce. Flour gravies would be better to use if you had to make a day ahead.

4. Opacity versus Translucency Opacity – refers to how much an object blocks light Maximum Opacity = no light going through it Flour is used suitable for chowders and white sauce, which are opaque. Translucency – how much light can pass through an object Maximum Translucency = blocks no light Cornstarch and potato starch are good for fruit sauces and glazes, which are translucent.