Antinutrients
How to properly prepare legumes /beans before cooking them to remove antinutrients such as lectins and phytates
How to prepare legumes /beans: Soak + Sour or Sprout before cooking
To reduce antinutrients, such as certain
lectins
(irritate gut lining, possible cause of auto immune disease)
and phytate , (affect
mineral absorption, inhibit digestive enzymes), legumes
generally need to be SOAKED before cooking them at a high temperature.
The lectin agglutinin, phytohemagglutenin (PHA), is the presumed toxic lectin
inherent in many bean species, and is particularly concentrated in
red
Noah ND, Bender AE, Reaidi GB Gilbert RJ, Food poisoning
from raw kidney beans, (1980) Br. Med. J. 281(6234):236-7
PubMed
In addition to soaking ,
you can also choose to sprout
or ferment legumes. These extra steps make legumes even more digestible and
nutritious.
Sprouting is generally followed
by cooking. However, "raw foodists" prefer not to cook them,
since they
want to preserve enzyme activity destroyed by boiling.
Fermenting requires that
the beans are cooked either before or after fermentation.
Fermenting them after cooking, avoids a bad
smell that emanates from uncooked fermenting beans and reduces cooking times.
Fermented soybeans are called "natto".
Although sprouting
and fermenting beans does reduce lectin activity, the most effective method to use after soaking is boiling at a HIGH temperature ,
preferably with a pressure cooker, which is almost as effective at reducing dietary
lectins as avoiding them.
FIRST - Soak Legumes / Beans - To remove phytate
Soaking beans for 18 hours reduces phytic acid in beans by
up to 70%, depending on type of bean;
• Soak legumes/beans
in water for 7-24 hours to remove phytates. Use a bowl
3-4 times the volume of the dried beans to allow for swelling; completely cover
beans with water; change water frequently to get rid
of phytic acid that leached into the water;
Some beans do better soaking in
an acidic medium. Depending on type of bean, add suggested amount of apple
cider vinegar, whey, kefir, plain yogurt or lemon juice;
Approximate amounts
Acidic medium Soak time
(Beans will swell 2-3 times their dry size)
2 cups black beans
2 tbsp
24 hours
2 cups black eyed peas, pinto, navy etc.
beans
warm water
12-24 hours*
2 cups red kidney beans
warm water
12 hours
2 cups split peas
warm water
7 hours
2 cup lentils
2 tbsp
7 hours
1 cup chickpeas
2 tbsp
24 hours
* SMALLER BEANS NEED A LONGER SOAKING TIME
• Rinse beans
after soaking. Using a sieve makes it easier to rinse off the bubbly scum
on top of the beans (btw, these gassy bubbles are what some people experience after
consuming unsoaked beans - need I say more? :) )
NOTE: Soaking deactivates
some lectins, but high-heat boiling does a superlative job. E.g. In PHA-inactivation
tests, soaking red kidney beans for several hours deactivated about 75% of its hemagglutinins
(53,000hau/g dry weight of sample to 18 hau/g, white kidney beans didn't change
much (17hau/g to 14 hau/g), and broad beans, with low amounts (3 hau/g), didn't
change at all;
Noah ND, Bender AE, Reaidi GB Gilbert RJ, Food poisoning
from raw kidney beans, (1980) Br. Med. J. 281(6234):236-7
PubMed
SECOND - After soaking legumes your choices are:
(i) Cook legumes at HIGH heat
(ii) Sprout legumes before cooking
them (However, "raw-foodists" prefer not to cook them after sprouting)
or (iii) Ferment legumes before
or after high-heat cooking
(i) Cook legumes at HIGH heat
Benefits of Cooking Legumes / Beans
Cooking kills bacteria and breaks down difficult-to-digest
starches
Effectiveness at reducing antinutrients
E.g.
Cooking red kidney beans at high temperature reduces
PHA lectins by 99% - although even small amounts have an inflammatory effect.
• Raw = 20,000 to 70,000
hau (hemagglutinating unit)
• Fully cooked at high temperature
= 200 to 400 hau
How to Cook legumes
• In fresh water, boil
beans for at least 15 minutes using HIGH heat.
Using a pressure
cooker reduces lectins even more, reduces cooking time to ~8 mins;
WARNING:
Beans cooked in too low a temperature
(e.g.in a slow cooker) can actually increase lectiin activity
Note on canned beans : canned beans are
almost lectin-free because the canning process uses sufficient heat to reduce lectins
to insignificant amounts; however, beans used in canning
typically have not been soaked long enough to remove
phytates
before being cooked ; One exception, a ccording
to their website, EDEN canned beans are
soaked, the soaking water discarded, and then the soaked beans steam-blanched
and rinsed before being pressure-cooked for a specified amount of time depending
upon the bean variety.
Cooked beans can be frozen for later use
or (ii) Sprout ("Germinate")
Legumes
Benefits of Sprouting beans
• Reduces lectins,
tannins, phytates;
• Increases vitamins
/ protein - depending on the bean
• Reduces carbohydrate
• Makes beans
(also grains, nuts, seeds) easier to digest - by breaking
down complex sugars and starches in the beans and unlocking digestive enzymes; this
also favors beneficial gut flora;
• Reduces gas;
• Decreases aflatoxin
- a carcinogen naturally present in some seeds E.g. peanuts, corn, almonds and other
nuts
• Slightly
milder taste than unsprouted legumes;
Effectiveness of sprouting at reducing antinutrients
• Reduces phytate
- ~30-80% depending on bean; sprouting increases phytase enzyme activity to break
down phytate;
• Slightly decreases
lectins and protease inhibitors;
Ref.
How to Sprout legumes
WARNING: sprouting
lentils increases lectin activity
• Drain rinsed beans
after soaking and place in a sprouter out of direct sunlight;
• Repeat rinsing and
draining - every 8-12 hours;
• Beans should sprout
in a few days - depends on bean type
High-heat cook sprouted legumes
Sprouted legumes will cook a bit
faster than unsprouted ones
(iii) Ferment legumes before or after high heat
cooking
Benefits of Traditionally Fermenting Beans
• Traditional fermentation
allows beneficial bacteria to eat lectins;
• Fermented legumes
contain probiotic bacteria;
• Reduces
phytates. Increases phytase enzyme activity, which breaks
down phytic acid; 2011 study showed a several fold increase depending on grain
Marshall Arebojie Azeke et al, Effect of germination on
the phytase activity, phytate and total phosphorus contents of rice (Oryza sativa ),
maize (Zea mays ), millet (Panicum miliaceum ), sorghum (Sorghum
bicolor ) and wheat (Triticum aestivum) (2011) J Food Sci Tech
Dec, 48(6): 724-729
PubMed
NOTE: Eden brand
fermented beans uses traditional fermentation methods after washing,
soaking and cooking the beans
prior to being fermented.
How to Ferment Beans
Not yet available
