paper for food

Would you throw to garbage food? especially when thinking about so many poor countries existing on the globe struggling to find food? I can tell that there are some people doing this out there and it's a really sad habit. OK, I understand, perhaps those people are not interested in food but surely they are interested in money. So let me ask you again: would you throw money on the window? Of course not. Unless we do not change our habit of wasting precious material that could be transformed into food we are actually loosing and not winning. 

The above picture is showing a sac of beautiful oyster mushrooms growing on cardboard paper, while below you'll see the entire cultivation process which is so simple that even a 5 year old boy could do it.
Paper is made out of cellulose material  such as trees. Perhaps you are familiar with the news on the Amazonian deforestation. Some companies are using the wood derived from the Amazonian forest to obtain paper while the majority of us are using this paper and then trow it to the garbage. At least we can do something about it: we can recycle it or I could say we can transform it into food and we can sell the food in order to get money. 

What type of paper is it suitable for mushroom cultivation?
Generally all type of material that includes cellulose. I prefer to use cardboard paper because it is not treated with who knows what type of chemicals. However, in order to be sure of this first I used to wash the paper and then use it in the mushroom cultivation process. Although cultivation of oysters on cardboard paper is labor (as you can see below) it is recommended in those areas where sawdust or straw is not available.
I heard that is even better to cultivate mushrooms on paper than on one type of sawdust especially because paper could be derived from a mix of  several types of wood and therefore richer in nutrients.

Probably white or colored paper or even written paper (e.g., books) has some chemical additives used in making the paper colored. Ink used in the process of printing before 1980 contained lead; however, now lead is not part anymore of ink available in the markets. Anyway, I prefer to not use any printed or colored paper if possible, because I want to keep the final product free of any possible chemicals. Oyster mushrooms are able to accumulate heavy metals and any pollutants available in the air or in the substrate on which they grow therefore precaution it is important.

Steps to follow:

1. Place the cardboard in hot water (50-60 C /122-140 F) for two hours trying to maintain the temperature at the same level.
2. Let the material to cool down (25-30 C /77-86 F).
3. The heat treated and cooled material has to be squeezed so that no water drops remain after this process.
4. The material has to be 'opened up' until it gets back to its original shape.
5. The paper is then mixed with gypsum (~ 2%)
6. Add the oyster mushroom mycelium to the mix
7. The material than is placed into a plastic bag
8. Holes are made on its surface for gas exchange
9. Leave the sac for 2- to 3 weeks at 15-23 C /59-73 F (indoors or outside)
10. Once primordia start to mature spray the sac with water (2 times/day)
11. After 3-5 days you may collect your mushrooms.
12. Wait another 10-14 days for a second wave of mushrooms and collect them as well.