Spilling the Beans on Soup

Prepared Foods, May, 2001 by Laura A. Brandt

Beans, peas, lentils and other legumes add exotic flavor, color, texture, fiber and nutrition to soup.

Due to cultural influences and adventurous consumer palates, the established legumes of split peas, lentils and navy and kidney beans--traditionally used in soups and other dishes--are being joined by more exotic varieties, such as black beans, cranberry beans and colored lentils.

We are becoming more familiar with the great variety of beans through various ethnic cuisines, including Hispanic, Asian, Mediterranean, Italian and Indian.

Furthermore, with the vegetarian movement both in the U.S. and abroad, more legume-based dishes are showing up on restaurant menus and store shelves. A recent USDA study revealed a 28% increase in bean consumption this past year.

Legumes add flavor, color, texture and nutrition to soup. Legume-based soups are generally high in fiber and protein and low in fat. Most dried legumes have a high iron and folic acid content.

Legume-based instant soup mixes and instant soup cups provide a quick and convenient way for consumers to enjoy a steaming bowl of soup.

Dried Legumes

Many bean, pea and lentil soups are sold as a dry mix. The U.S. is a leader in dry bean production.

Although there are thousands of varieties of legumes in the world, the U.S. only grows about 15 varieties, says Janelle Sterner, director of culinary services, Inland Empire Foods, a California bean supplier. India, for example, uses over 1000 varieties of legumes in its cuisine.

Growing and processing conditions effect the quality of the beans. After harvesting and sorting, the beans are cleaned, steam-cooked and dried in an atmospheric oven. Steam is used to preserve flavor, color and nutrition, says Sterner. During processing, up to 15% of the solids are lost in the cooking water.

Instantized beans can be dried by infrared, dehydration, freeze-drying or drum-drying. Dehydrated beans are less expensive than freeze-dried or drum-dried beans. They are the best choice for functionality, flavor and texture in most applications, notes Sterner.

Proper harvesting and storage at the right temperature are keys to ensuring the quality of the beans. When choosing raw beans, the moisture should be between 10-15% and the color should be light and uniform, reports Sterner. Water and heat damage tends to darken or discolor beans. Raw beans tend to darken with age as well. Because age effects cook quality, Sterner recommends buying the current crop year to ensure freshness.

Deciding which beans and bean ingredients to use in a soup application involves several key considerations:

* Selection. Formulators should have a final product in mind when selecting the type of bean for a particular application. There are many varieties to choose from that sound and look more exotic than the more commonly used varieties. For example, Red Chief is a type of red lentil.

* Performance requirements. Preparation method or instructions, rehydration time, further processing or holding time must be considered.

Most instant soup cups rehydrate in five to eight minutes after adding boiling water. "Everyone wants a bean that rehydrates quickly," says Sterner. "We can customize the rehydration rate for any bean variety by adjusting our processing parameters. The fastest hydrating whole beans--black, pinto and red--rehydrate with either a five-minute steep or a three-minute simmer."

* Target appearance. Determining the appearance and integrity of the finished product is the key to choosing legume ingredients.

Legume ingredients are typically available in whole, pieces, flakes or flours. Defining parameters, such as firmness of the bean, whole bean versus bean pieces or broth soup base versus a creamy soup base, help determine the appropriate bean ingredients.

Using slightly crushed beans provides a "homemade" look and broken pieces deliver more of a creamier background. A flaked product may be used to provide thickness and to dissolve into the stock.

* Performance limiting or enhancing ingredients. Formulators need to consider other ingredients that effect water absorption, such as rice, pasta, seasoning, dehydrated vegetables, starches and thickening agents. For example, a whole bean that simmers with rice will retain its integrity better than a whole bean simmering alone in liquid. A whole bean designed to rehydrate in 20 minutes after simmering in water will not soften as quickly in the presence of starches or thickening agents. A bean with a quicker rehydration rate should be selected, based on the addition of the thickening agent.

Dried beans are also affected by pH changes. For example, acid hardens the skin of the beans while alkali causes skin sloughing. For a dry soup mix, suppliers can process the beans to hydrate in an acidic formulation.

In order to avoid problems with hygroscopic ingredients, such as spices and salt, suppliers can incorporate them into a bean flake. This helps to ease rehydration for the consumer.

Legume powders are label-friendly ingredients, which can be used as thickeners, flavor and aroma enhancers, and texture and color enhancers in soups. The powders can be derived from peas, beans or lentils. Some modified starches can be replaced with legume powders.