What is tofu really made of?
Food science is a very broad subject, through a semester of study food science, I have a deeper understanding of food science. Such as how long food stays fresh, how to preserve food to avoid oxidation, food allergies, food additives, and even food law, etc.
Through these courses, I have learned that food science covers the principles of food, food safety and storage, food composition……This semester, we studied topics such as cheese making, dairy products, and wine making. So I was curious about how to make one of my favorite foods. I would like to introduce you to a unique Chinese food, tofu. It is a very delicious and nutritious food.
“Tofu, also known as bean curd, has a long history of being produced in China. The first record of tofu making in China goes back over 2,000 years (the Chinese Han dynasty) (Zhou, Tian, & Wang, 2017). Although many scholars believe that tofu made in the Han Dynasty was simple, lacking firmness, and flavor, it was recognizable as tofu. It became a popular food in China during the Song Dynasty (960 to 1279) (Buell, 2018; Needham, 1976; Wilkinson, 2012). Over time, its production technology matured in China and spread all over the world with the advance of its science and technological development.” (Li, 2020)
The raw materials and components
The main components of tofu are soy protein, oil and carbohydrates, 120 grams of protein contained in tofu, equivalent to the protein contained in an egg, tofu is comparable to the nutritious lamb, every 100 grams of protein contained in tofu than the same amount of protein contained in lamb to more than two point two grams. Furthermore, the main raw materials of it are soybeans and water. In addition it becomes mostly made from soybeans, black beans and peanut beans, which contain high protein. Soybeans are rich in protein, with 36-40 grams of protein in 100 grams of soybeans.
The production of Tofu
Moreover, the production process of tofu becomes divided into two main steps, making soybean pulp and making soybean pulp solidify into tofu.
Making soybean pulp: that is, soybean pulp is made from soybeans; after water immersion, grinding, dross removal and heating, the colloid of protein becomes obtained, a mixture between solution in addition suspension, emulsion.
Soybean milk solidification and forming: after cooking the soybean milk must then carry out two processes of pulp spotting and pulp wrapping. That is, soybean milk in the joint action of heating and coagulant solidification into a gel containing a large amount of water.
One of the few superfoods considered a healthier alternative to fish. In addition, can become used in many meat substitutes, such as sausages and burgers.
Chemical principle of tofu spotting
Dotted tofu uses the phenomenon of coalescence of colloids. Moreover, when an electrolyte solution is added to the colloid, the added cations (or anions) neutralize the charge of the colloidal particles, causing the colloidal particles to aggregate into larger particles, causing the protein to coalesce and separate from the water, thus forming a precipitate that precipitates out of the dispersion system.
“Tofu represents an excellent source of many nutrients like protein, vitamins and minerals, which are highly imperative for keeping good health. The antioxidant and anti-inflammatory properties of soy peptides found in fermented soy food like tofu can help to protect the blood vessels from oxidative and inflammatory damage. Research indicates that eating soy-based products can prevent breast cancer, osteoporosis, and cardiovascular disease. Menopausal women can rely on tofu for production of oestrogen. It also helps to bring down the incidence of hot flashes in women. Persons with low immunity are susceptible to infections. Therefore, tofu plays an important role in building strong immune system that provides a shield against some infections.” (Mahendra, 2019)
The health benefits are summarized as follows:
“High blood cholesterol and hypertension are the common health problems, which may occur due to meat consumption. Tofu being rich in good cholesterol and omega-3 fatty acids, can remove all the harmful effects meat causes to our health.
- Firstly, it strengthens muscle and bone health.
- Secondly, it reduces bad cholesterol level (LDH) and thus, prevents heart problems
- Thirdly, it enhances body weight loss.
- Fourthly, t prevents migraine headaches.
- It regulates blood sugar and helps in diabetes.
- It prevents prostate cancer in men.
- It Inhibits ageing process.
- It eases menopause symptoms in women.
- It helps to prevent osteoporosis.
- It prevents kidney diseases.
- It maintains cardiovascular health.
- It prevents anemia.
- It prevents liver damage.
- It improves brain health.
- It prevents hair loss.
- It prevents endometrial cancer in postmenopausal women.
- It reduces the risk of lung cancer.
- Lastly, it boosts immunity.” (Mahendra, 2019)
In the summer, the freshness of tofu will become very short. Only one day, even if it is placed in the refrigerator. It can only become stored for about two days at most. If not eaten to the next day the tofu becomes sour, that is, spoiled. Tofu is generally put in the refrigerator. Or soak in water with some salt, change the water every day while adding a little salt. This method can be stored in the summer for at least two days, the winter can be put for at least three days or so. But also limited to three or four days only
In conclusion, I hope you will have a better understanding of tofu through my explanation. Tofu is a highly nutritious and very tasty food. It is very suitable for people who have a healthy diet requirement. There are also many different ways to make tofu, so you can learn about them when you are cooking. Lastly, I hope we can all explore the food around us with a food science perspective.
Written by Yitong Su
Li Zheng, Joe M. Regenstein，Oct 03, 2020. Tofu products: A review of their raw materials, processing conditions, and packaging, IFT, https://doi.org/10.1111/1541-4337.12640) Mahendra Pal, Mridula Devrani &Yodit Ayele, 2019, Tofu: A Popular Food with High Nutritional and Health Benefits， Ingredients&Additives , https://www.researchgate.net/profile/Mahendra Pal-9 publication332343856_Tofu_A_Popular_Food_with_High_Nutritional_and_Health_Benefits/ links/5caef2caa6fdcc1d498c22dc/Tofu-A-Popular-Food-with-High-Nutritional-and-Health Benefits.pdf