Can you eat the iron stick yam when it turns purple?

There are many foods in life that people like, but when there is more food storage, there will be big changes. In particular, the problem of spoilage is very serious, because it not only affects the taste, but most importantly, it will cause harmful effects on the human body. The same goes for iron stick yam. If the storage method is incorrect, it will affect people's health. So can we eat the iron stick yam when it turns purple?

Can I still eat yam if it turns purple?

Normal purple can be eaten

The skin of some yams has a layer of purple, which is related to the soil and variety in which they are planted. Iron stick yams are the most common. After peeling, the yam flesh inside still has a layer of light purple. This kind of purple yam can be eaten with confidence. Yams contain phenols and classified oxidases, while the air contains oxygen. After the yams are peeled, a reaction will occur. The generated quinones will appear brown or black. Slightly oxidized yams will also appear light purple, which can also be eaten.

Do not eat if it turns purple abnormally

Yams can be stored for a long time just like sweet potatoes and potatoes, but you need to pay attention to the loss of moisture in the yams. If they are stored for too long, the moisture in the yams will be lost in large quantities, or part of them will begin to rot, and the heart of the yam will turn purple. This kind of yam contains certain toxins and is not suitable for consumption.

Why does yam turn purple?

It is normal for yam to turn purple-red after peeling, because iron stick yam contains rich elements.

1. Purple is the sign of iron stick yam. Generally, there is no purple on the yam. It is rust. There is no problem. You can see it without peeling it. After peeling, there is a light purple layer. It is normal.

2. The purple color is usually on the inside, and you can see it after peeling off the skin. This purple color is usually only seen in winter and is rarely seen when the weather gets hot.

3. The purple and browning produced after peeling are mainly caused by three conditions: polyphenols, polyphenol oxidase and oxygen. After the yam is peeled and exposed to the air, the polyphenols in it react with oxygen to produce o-quinone, which is further oxidized and polymerized to form brown pigment and melanin.

The efficacy and function of yam

1. Strengthen the spleen and stomach

Yam is a food and medicine that nourishes the spleen and stomach. It contains substances such as amylase and polyphenol oxidase, which are beneficial to the digestion and absorption function of the spleen and stomach. It can be eaten regardless of spleen yang deficiency or stomach yin deficiency. It is often used clinically to treat spleen and stomach weakness, poor appetite, fatigue, diarrhea and other symptoms.

2. Nourishes the kidneys and improves essence

Yam contains a variety of nutrients, which can strengthen the body, nourish the kidneys and improve the essence. It can be taken for symptoms such as kidney deficiency, spermatorrhea, excessive leucorrhea in women, and frequent urination.

3. Nourishes the lungs and relieves cough

Yam contains saponins and mucus, which have lubricating and moisturizing effects, so it can benefit the lung qi, nourish the lung yin, and treat lung deficiency, phlegm, cough and long-term cough.

4. Lowers blood sugar

Yam contains mucus protein, which has the effect of lowering blood sugar. It can be used to treat diabetes and is a good food therapy for diabetics.

5. Prolong life

Yam contains a large amount of mucus protein, vitamins and trace elements, which can effectively prevent the precipitation of blood lipids in the blood vessel walls, prevent cardiovascular diseases, and achieve the effects of improving the mind, calming the nerves, and prolonging life.

6. Anti-hepatic coma

Recent studies have found that yam has a sedative effect and can be used to prevent hepatic coma.