Tofu is one of the oldest foods, and it has been a hot topic of discussion by food critics in recent times.
Many clamors about its health benefits and versatility but some others consider it as a genetically modified poisonous diet.
Whatever may be the discussion, tofu has been in use for 2,000 years; and it is a very popularly used food component in many Asian cuisines.
There is a growing interest in tofu all over the world although many still doubt whether this food is healthy enough to be part of the daily diet.
This article elucidates the making process, nutrition, health benefits, and side effects of this popular food.
What is Tofu?
Tofu is a processed soybean food component eaten by people of China, Thailand, Japan, and other East Asian and Southeast Asian countries.
A staple ingredient in Thai and Chinese cookery, there are several ways to cook this food by changing its texture from smooth and soft to crisp and crunchy.
According to Chinese folklore stories, it was first discovered by a Chinese woman-cook when she accidentally mixed a cup of fresh soy milk with nigari.
Nigari, a mineral-rich by-product of the salt-making process, is a versatile pantry staple. It is basically the mineral-rich coagulant leftover after the salt is extracted from seawater.
The minerals like Magnesium Chloride or Calcium Sulfate found in coagulants help to solidify the processed soy milk into tofu.
How To Make Tofu?
Tofu, or bean curd, is a popular food derived from soya.
If you are wondering how to make tofu, it involves only a few steps very similar to making the traditional dairy cheese.
The soy cheese is made by curdling the fresh soya milk, pressing it into a solid block, and then cooling it to solidify.
Ingredients For Making Tofu
The ingredients that go into the making of Soya-Cheese are soy milk and any one of the commonly used coagulants like Nigari (Magnesium Chloride) or Terra Alba (Calcium Sulfate). Lemon juice could also be used as a coagulant.
For making soybean curd at home, the following proportion of ingredients could be used:
- Soy Milk – 8 cups /64 Oz
- Coagulant – 2 tsp Terra Alba OR 1 tsp Nigari Flakes OR 1/2 tsp. Liquid Nigari
How To Prepare Tofu? – A Step-By-Step Guide
Here are the simple procedures of making soy cheese:
- Boil fresh soy milk for 5 minutes (boiling is not required if you are using the pasteurized and sterilized soy milk)
- Coagulant should be dissolved into a cup of warm water and added to the soy milk and gently stir till the mixture is properly blended.
- After stirring, leave this mixture untouched for 30 minutes or till the small lumps of curd are fully separated from the amber-colored liquid.
- Transfer the curds into proper sieve containers lined with cheesecloth and tightly fold the cheesecloth over the lumps of curd.
- Press the curd bundled up in the cheesecloth to drain out the water; place a heavy-weight object over the bundle or mold for 30 minutes for fully draining out the liquid and hardening the dry curd.
- The tofu is ready by now. You can use it immediately for cooking or keep it under refrigeration for further solidifying and preservation.
Tofu Nutrition, Calories, And Protein
The soy cheese contains a good quality protein that includes 8 essential amino acids. The other major contents of soy curd are fats, vitamins, minerals, and carbs.
Tofu is an excellent source of calcium and a very good source of manganese, copper, selenium, protein, and phosphorus. In addition, tofu is a good source of omega-3 fatty acids, iron, magnesium, zinc, and vitamin B1.
Wondering how many calories are in Tofu, Firm? Every 100gm of tofu contains 76 calories or 41 calories per ounce. Soy cheese is a medium-calorie food, and moderate eating of any soy product is not a problem for people on low-calorie diets.
It is a ‘complete protein’ food though tofu protein is not considered as high-quality as animal sources. It has 8 out of 9 essential amino acids that must be included in the “complete protein” category foods.
Every 100 grams of tofu contains 8 grams of protein.
All soy products contain a high amount of protein and fewer amount of calories; this makes all soy foods healthy.
100 grams of Tofu Serving contains:
- Carbs: 2 grams.
- Fiber: 1 gram.
- Fat: 4 grams.
- Manganese: 31% of the RDI.
- Copper: 11% of the RDI.
- Magnesium: 9% of the RDI.
- Calcium: 20% of the RDI.
- Iron: 9% of the RDI.
- Selenium: 14% of the RDI.
- Phosphorus: 12% of the RDI.
- Zinc: 6% of the RDI.
- Vitamin A: 2% of RDI
- Vitamin B-6: 5% RDI
Note: Calcium amount will be higher in tofu made of Terra Alba coagulant and similarly, magnesium will be higher if Nigari is used.
Is Tofu Healthy? | The Benefits Of Bean Curd
Tofu is high in protein and contains many healthy nutrients.
Eating tofu may protect against a variety of poor health conditions, such as heart disease, diabetes, and even certain cancers.
Here are a few of the tofu benefits:
Benefits Of Isoflavones
It is a natural plant compound present in soybeans that functions as a phytoestrogen that helps to activate estrogen receptors in the body.
The two main isoflavones in soy are genistein and daidzein that give several health benefits to the body.
Reduces Heart Diseases
According to various study reports, a high intake of legumes, especially soy products, is connected to lower rates of heart diseases.
Most importantly, all soy products have isoflavones plant compounds that can improve blood vessel elasticity and reduce inflammation.
According to a 2008 study published in the European Heart Journal, the high-risk stroke patients who took 80 mg of isoflavones per day for 12 weeks had improved blood flow by 68%.
In another research report published in The American Journal Of Clinical Research, it is noted that taking 50 grams of soy protein per day is good for improving blood cholesterol levels and reduces the risk of heart diseases by 10% or more.
The saponins plant compound present in the tofu is beneficial for improving heart health.
Reduces Diabetes Risks
Several research and studies of the past have indicated that isoflavones compounds in soybeans have the ability to control blood sugar levels.
According to a 2004 study published in the Journal Of Women’s Health, a group of healthy postmenopausal women who took 100mg soy isoflavones per day reduced insulin levels by 23% and sugar levels by 15%.
Another study report in Diabetes Journal showed that taking isoflavones regularly helps in improving insulin sensitivity and blood cholesterol, which reduced the risks of diabetes and heart diseases.
Reduces Some Cancer Risks
There are several verified pieces of evidence from various studies that indicated the effects of tofu on colon, breast, and prostate cancer reduction.
Studies show that women who eat soybean products at least once a week have a lower risk of developing breast cancer.
A 2013 study in The Journal Of Nutrition observed that a higher intake of tofu helps in lowering the risk of stomach cancer in men and women.
A 2009 study by Lin Yan1 and Edward L Spitznagel for the American Society For Nutrition, observed that 633,476 participants linked higher soy intake to a 7% lower risk of cancer of the digestive system.
Another two prominent studies have also found that increased intake of soy products like tofu help lower the risk of developing prostate cancer by 32–51%.
Beneficial For Weight Loss
Studies have reported that regular intake of soy isoflavones results in weight loss.
Enhanced Brain Function
Soy isoflavones are found to have a great influence on enhancing memory and brain function.
Improves Bone Health
Evidence from research suggests that 80 mg of soy isoflavones are taken daily can reduce bone decay especially for the woman in the post-menopause period.
Makes Skin Healthy
Wrinkles on the skin can be reduced, and skin elasticity can be improved by taking 40mg of soy isoflavones daily.
Are There Any Side Effects Of Tofu?
Despite divided opinions on the goodness of tofu, NO evidence indicates any serious harm it can inflict on health.
However, no food is good for health if eaten in an excess amount. It is good to limit the intake of bean curd to a moderate amount.
Some of the possible ill effects of soy products on health are:
- The oxalates in tofu can aggravate the kidney or gallbladder stones issue.
- Women with estrogen-sensitive breast tumors should limit the intake of tofu as this soy food has weak hormonal effects.
- The goitrogen content in tofu is bad for women suffering from Thyroid issues.
- Soy isoflavones are not good for infants as they may disrupt the development of reproductive organs.
- According to some animal studies, soy products could have adverse effects on fertility health.
The anti-nutrients in tofu may not be healthy for some people with weak metabolism and digestive function. These anti-nutrients may lead to:
- Inhibition Trypsin, an enzyme that is required for the digestion of protein
- Lectins protein in soy can cause bloating and nausea if eaten raw
- Phytates present in soy reduce the absorption of minerals.
However, most of these antinutrients in soy can be made ineffective by soaking, cooking, or fermentation.
Sprouting soybeans before making tofu can also help in eliminating most phytates and trypsin inhibitors; on the positive side, it increases the protein content.
Tips On Choosing Healthy Tofu
Either you can make tofu at home or purchase tofu which comes in various forms like freeze-dried, jarred or canned, or dehydrated.
When you are buying soy cheese, make sure to read the ingredients label and find that only soybeans, water, and permitted coagulants are used in it.
It is important to rinse the tofu blocks before you use them in your food.
Tofu must be stored in the refrigerator; the open blocks or leftover pieces of soy cheese must be dipped in water and stored.
It is not advisable to use packaged tofu that is more than 5 months old.
If you can make fresh tofu at home, there is nothing better than that.