In our last class, we talked about vitamins. Today, let's discuss dairy products! The main focus will be on three types of dairy products we commonly encounter: fresh milk, yogurt, and milk powder. They are closely related yet distinct. In terms of nutrition, they contain basically the same types of nutrients, but with some differences.
Fresh milk contains almost all the nutrients the human body needs, except for dietary fiber, and it is easily digested and absorbed, making it a nutritious food suitable for most people. It is worth mentioning that fresh milk is high in calcium with a high bioavailability, making it an excellent source of natural calcium. Therefore, it is recommended to drink fresh milk daily.
Fresh milk contains almost all the nutrients the human body needs, except for dietary fiber.
Yogurt is made by pasteurizing fresh milk, inoculating it with *Lactobacillus acidophilus*, and fermenting it for 4-6 hours at around 30°C. Yogurt is rich in nutrients, easily digestible and absorbable, and can also stimulate gastric acid secretion.
Milk powder is made by pasteurizing, dehydrating, and drying fresh milk into a powder. After heat treatment, the protein curds in fresh milk are small, soft, and easy to digest and absorb. It is also sterilized, causing fewer allergic reactions. Only volatile fats, sugars, and vitamins are slightly reduced. Compared to fresh milk, the biggest advantage of milk powder is that it is easy to transport and store. Instant milk powder is particularly convenient to prepare quickly.
When reconstituted into liquid milk, its nutritional value is similar to fresh milk. Due to the recognized health benefits of yogurt and the strong market interest from many manufacturers, new products are constantly being introduced with various bacterial strains, giving consumers more choices.
The main difference between yogurt and milk is the addition of *Lactobacillus*, which breaks down the lactose in milk into lactic acid. Research has found that when lactic acid is combined with calcium, it is most easily absorbed by the human body. Therefore, yogurt is very suitable for adolescents in their developmental period or women who are prone to osteoporosis during menopause. Additionally, it creates an acidic environment in the gastrointestinal tract, which also helps with iron absorption.
The main difference between yogurt and milk is the addition of *Lactobacillus*.
When it comes to calories, it's essential to understand its ingredients. Although different brands may vary, the contents generally consist of cow's milk, oligosaccharides, pectin, fructose, and flavorings. Since people generally find plain yogurt too sour, manufacturers often add sugar or fructose for flavoring, which adds a significant amount of calories.
A 240cc serving of low-fat milk contains about 120 calories, whereas the same amount of low-fat yogurt contains 150-200 calories (depending on the brand). Therefore, the calorie content is higher than one might expect. If you want to consume a lower-calorie yogurt, it is recommended to choose a product labeled as "skimmed" and "low-calorie," as a 240cc serving of this type contains only about 100 calories. Generally speaking, yogurt still has more calories than milk. For those concerned about weight gain, it is important to carefully choose the brand and type, and to limit the amount consumed, otherwise, you might unknowingly ingest a lot of calories.