Transcript Legumes - Marblehead High School

Legumes
Dried seeds from plants of the
Leguminosae family.
Examples: navy beans, kidney
beans, pinto beans, split
peas, lentils.
Nutritive Value
 High in protein, methionine is limiting
amino acid
 Low in fat (most)
 High in carbohydrates
 High in fiber
 Good sources of iron, thiamin, riboflavin
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Hydration
 Legumes must be hydrated before
cooking. Water passes through the hilum
(where seed is attached to the pod)
 Soaking methods
 1. Soak overnight in cold water
 2. Bring water and beans to a boil, soak
1 hr
 Need 2 1/2 to 3 cups of water per 1 cup
beans
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Cooking
 Pectin content, water content, water
hardness, soda, pressure, and phytase
effect cooking time.
 Legumes should be cooked until tender
before adding
 1. Calcium - insoluble Ca pectate
forms which prevents legumes from
becoming tender. Examples: molasses,
brown sugar, canned tomatoes, hard
water
 2. Acid - insoluble pectic substances
form preventing tenderness. Examples:
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Other Vegetable Proteins
Soybeans
 Good source of high biological value
protein
 Soybeans may have objectionable off
flavor called “painty” or “beany” thought
to be due to lipoxygenase. Techniques
have been developed to inactivate the
enzyme
 Soybeans contain phytoestrogen, a
isoflavonoid, which has weak
estrogenic effects in body. Some soy
products contain isoflavonoids, others
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Textured Vegetable Protein
 Fiber formation - solution of high protein
concentration is spun into long fibers,
placed in a coagulation bath and
compressed or bound together
 Extrusion - protein concentrates or
flours are mixed with water, pushed
through a cylinder (turning screw).
Moisture is evaporated forming dry
fibrous, porous granules or chunks
 Usually combined with other foods
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Tempeh
 Fermented (cultured) food consisting of
tender cooked soybeans (or other
legumes, seeds or cereal grains) bound
together by a dense cottony mycelium of
Rhizopus mold.
 Formed into compact white cakes or
patties.
 3 1/2 oz = 19.5 g protein and 157 kcal
 May have acid flavor from fermentation so
is often flavored and mixed with other
foods.
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Tofu
 Soaked soybeans are pureed and then
cooked, and filtered. Resulting milk is
curdled with a coagulant (MgCl) and curds
are pressed into cakes allowing whey to
drain off.
 3 1/2 oz = 10 g protein and 80 kcal
 Bland flavor, texture depends on amount
of water removal.
 Can be used in a variety of dishes.
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Soy Milk
 Soft cooked soybeans are ground and the
liquid is extracted.
 Liquid contains soy protein, oil, and other
solids.
 Usually fortified with calcium
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Seitan
 Gluten protein extracted from wheat.
 May be purchased wet or dried
 One patty 1/3 cup = 21 g protein
 Has texture similar to meat and is used in
stews or in making vegetarian patties
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Nuts
 Botanically classified as fruits
 Rich in protein, high in fat, high in niacin
and most are good sources of thiamin
 Marketed shelled and unshelled
 Precaution needs to be taken to prevent
rancidity by use of antioxidants
 Often used in vegetarian diets to
complement bean or cereal protein
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Power Point Authors
 Jon Christiano
&
 Dr. Jane Ross
 The University of Vermont
 Foods and Nutrition
 Basic Concepts of Food
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