Transcript 5. Texture
5. Texture • Texture – the feel or appearance of a substance • Cornmeal will thicken gravy, but most people would not like it because it would feel gritty instead of smooth Modified Starches • Food technologists can alter the structure of starch molecules to achieve special physical properties such as sweetness, particle size, viscosity, appearance • FDA does not require the labels identify the original food product that was modified, which can cause issues for people that are allergic to specific grains • Most common modified starch in the U.S. is corn Modified Starches Continued… • Cross-linked starch is changed so that the starch is more resistant to acids (which break down starches), separation (during freezing and thawing), and increasing the shelf life of the product – Used by food scientist to make baby foods, salad dressings, cream-style corn and fruit pie fillings. – Frozen entrees and instant, quick-mix foods would not be possible without these cross-linked starches Thickening Sauces with Starch • 3 ways to thicken sauce with starch 1. Cold water paste 2. Starch and fat 3. Starch and sugar • Each method is used to prevent lumps and achieve the desired flavor 1. Cold Water Paste • Quickly stirring starch while adding at least an equal amount of cold water until a smooth paste is formed • Used to thicken soup stock, or milk/broth gravy 2. Starch and Fat • An equal amount of starch is added to heated fat • Examples – Beurre manie: mixture of equal parts butter and flour. Can be added to hot soups to thicken the broth – Roux: mixture of equal parts flour and fat. Adds a distinctive flavor to gravy or sauce 3. Starch and Sugar • Used in making sweet sauces and puddings • Sugar helps prevent lumping and viscosity (making the product smooth rather than rigid) Nutritional Impact of Complex Carbohydrates • 2 categories: digestable carbohydrates & indigestible fiber • Carbohydrates should provide over half of your calories • Carbohydrates in the form of glucose are the only energy source the brain can use. Nutritional Impact of Complex Carbohydrates Continued… • Excess carbs are stored as glycogen • Glycogen is more branched than amylopectin, which allows more glucose to be released at a time. This is why it is so important to eat carbs every 4-6 hours. If you skip breakfast, your body will slow brain and organ functions to conserve glycogen Nutritional Impact of Complex Carbohydrates Continued… • The more you exercise the more energy the muscles will store. The less you exercise, the less glycogen will be available when you need it. • Muscles store 2/3rds of the glycogen for physical exertion. 1/3rd of the glycogen is stored in the liver. Both stores will be used for the brain at any time. • If your glycogen stores are full, excess carbohydrates will be turned into fat Fiber, Bran, and Bulk • Scientifically known as cellulose • Refers to indigestible carbohydrates. Helps you feel full & aids in digestion. • Lack of fiber in the diet has been linked to increased risk of developing colon cancer. • Sources of fiber: vegetables, fruits, & grains. Nutritional Functions of Carbohydrates 1. Provide energy for bodily functions 2. Bulk for digestive processes 3. Lower cholesterol levels in the blood 4. Promoting the utilization of fat • Eat a variety of fruits and vegetables. Refined grains should be limited, since they are often high in added sugar and solid fats • 2 cups of fruits and 2 ½ cups of vegetables are recommended daily