Culinary Fundamentals - Ch. 7

Pulse

The edible dried seed of a leguminous plant; examples include dried beans, peas, lentils, and chickpeas.

Legumes

Edible seeds of leguminous plants, including dried beans, peas, lentils, and chickpeas.

Purée Soups

Thick soups that can be based on dried legumes and have a coarse texture.

Roux

A mixture of flour and pure fat, such as clarified butter or oil, used to thicken sauces, soups, and stews. Standard roux is 60% all-purpose flour and 40% fat by weight.

Long Soak Method

Place culled, sorted, and rinsed legumes in a container with enough cool water to cover by 2 inches. Soak in the refrigerator for 4 hours to overnight. Soaking longer than 24 hours may cause fermentation.

Short Soak Method

Place culled, sorted, and rinsed legumes in a pot with enough boiling water to cover by 2 inches. Let soak for 1 hour.

Thickening Agents

Ingredients used to increase the viscosity or thickness of a liquid; starch is a major thickening agent used in sauces and soups.

Starch Gelatinization

The process in which starch granules absorb water when heated, swell, and release starch molecules into the surrounding liquid, causing the liquid to thicken.

Starch Gelation

The process that occurs as gelatinized starch cools and starch molecules form bonds with one another, creating a more structured gel or thickened consistency.

Retrogradation of Starch

The reassociation of starch molecules after gelatinization as the mixture cools, causing the starch structure to become firmer or congeal.

pH and Minerals Associated with Legume Cooking

Calcium and magnesium in hard water toughen dried legumes during cooking. Acidic liquids slow softening by toughening cell walls. Alkaline liquids have the reverse effect and speed cooking. Salt slows water absorption and therefore lengthens cooking time.

What is the basic formula for purée soups using legumes?

1 cup legumes; cool stock or water as needed to keep covered throughout cooking; standard sachet d’épices or bouquet garni; mirepoix or other aromatic vegetables; and salt added midway through or at the end of cooking.

What are the 2 methods for rehydrating legumes?

Long soak method and short soak method.

What is the purpose of soaking beans prior to cooking?

To partially rehydrate dried legumes before cooking.

Do all legumes require pre-soaking?

No. Most larger varieties of legumes must be partially rehydrated before cooking, including navy, black, and kidney beans and chickpeas.

What is the effect of pH and minerals on the cooking of legumes?

Calcium and magnesium in hard water toughen legumes. Acidic cooking liquids slow softening by toughening cell walls. Alkaline liquids speed softening. Salt slows water absorption and lengthens cooking time.

What are the general guidelines for preparing purée soups?

Cull and rinse legumes; render bacon golden brown; add mirepoix, cover, and sweat; add legumes, sachet, and stock and bring to a simmer covered; cook approximately 40–45 minutes until tender and creamy; remove sachet and purée; adjust consistency and seasoning; finish with acid; heat, garnish, and serve hot.

What is the correct consistency for purée soups?

Coarse and rustic.

What additional complementary ingredients are traditionally used to complement the primary flavor in purée soups?

Smoked or cured pork, mirepoix or other aromatic vegetables, a sachet or bouquet garni, and an acid such as lemon juice or vinegar.

What is an appropriate garnish for a purée soup?

Croûtons, small-diced ham or bacon, pieces of the main ingredient, or minced herbs.

Define roux and give a ratio for its production.

Roux is flour and pure fat, such as clarified butter or oil, cooked together and used to thicken sauces, soups, and stews. Standard roux is 60% all-purpose flour and 40% fat by weight.

Why should roux be cooked before usage?

Cooking flour in fat inactivates the enzyme amylase, which interferes with flour's thickening ability if it is not destroyed by high heat.

What is amylase?

An enzyme that interferes with flour's thickening ability if it is not inactivated by high heat.

What are three colors of roux?

White, blond, and brown.

What happens to the thickening power of roux the longer it’s cooked?

It decreases. Cooking flour to a brown color lessens the roux's thickening ability and changes its flavor to a toasted or nutty flavor.

What is the standard ratio of roux to liquid to create a medium consistency of thickness using white, blond, and brown roux?

White or blond roux: 16 oz per gallon of stock or liquid. Brown roux: 18 oz per gallon of stock.

What are the advantages and disadvantages of thickening with roux?

Roux effectively thickens soups, sauces, and stews and adds flavor. Products thickened with roux are opaque or cloudy, and darker roux has less thickening ability.

Define the processes of starch gelatinization and gelation.

Gelatinization occurs when starch granules absorb water and swell when heated, causing thickening. Gelation occurs as gelatinized starch cools and starch molecules bond together to form a more structured gel.

Explain wheat starch gelatinization and activation and how they affect the thickening of liquids.

Starch activation begins around begins 126°F (52°C) as starch granules absorb water and swell. Gelatinization develops as heating continues and starch molecules fully swell and release starch molecules which occur through 185°F (85°C). This activates the starch’s thickening power; thickening increases with continued heating and reaches its maximum near the boil.

What does the term degradation refer to relative to thickening using a roux?

Degradation refers to the breakdown of starch molecules into smaller fragments when they are overheated or cooked for too long, which causes a sauce to lose its thickening power and become thin or runny