For the market, there are some food desiccant packages that look like plastic, making people feel airtight. Is this food desiccant effective? To answer your questions, let's look at the following

First of all, food desiccants are very useful. If they have no effect, no manufacturer will produce such products. The reason why people feel useless is that the moisture absorption process is static, which is difficult to distinguish from ordinary people's glasses. As for whether the outer packaging can absorb moisture through it, there is no doubt. These outer packaging are breathable. If you look carefully, there will be some small holes.
If you still can't understand it, we can do a small test. Take Wangwang Snow Cake as an example. You can pack it separately. One with desiccant and the other without desiccant. After a few days, the taste will be clear. The taste with desiccant must be much crisper than that without desiccant.
The main raw material of food desiccant is silica gel, whose moisture absorption rate is about 30%. It can also be said that 10 grams of silica gel desiccant can absorb about 3 grams of water. It can absorb moisture, which is no doubt, because it is scientifically verified.
Needless to say, the desiccant needs to be sealed and packaged. If it is not sealed, it will contact the outside air and absorb water in the air continuously,