Communicate with neighbors to exchange food

Germany’s problem regarding food is not that we don’t have enough, but that we have too much. Incredible amounts of food get thrown in the dustbin. If there was just a good system of sharing food, we could use food much more efficient. Also, it can save you money. If you buy products in big amounts it is usually cheaper than if you buy only one thing of something. So you could buy the big pack and then share with others. In this case, everyone profits. We all know the problem that sometimes you have to buy special ingredients that you need only for one dish and then never again. It gets old, and after some weeks you have to throw it away. Let’s avoid this waste!
I am convinced that this is quite easy to turn into reality. It doesn’t even need a huge project to get this organized. It is all about communication with neighbors. Since online communication is the easiest nowadays, I would suggest using a simple Google spreadsheet. Of course, when you get it started, you first need to advertise the system with putting up information sheets in the houses near you or talk to your neighbors personally. Interested people send you an email so you can collect all email addresses and start running the spreadsheet.
Anyone can edit the spreadsheet. You can write what you can offer to share or to exchange, and also what you would need. Also, contact details of the participants can be shared which makes it easier to contact the other person spontaneously.
This is an example of how it could look like:

When an exchange is accepted by both parties it is easy to actually exchange it, because you are neighbors and it will probably take you less than 3 minutes to get it.
This system doesn’t only work for bought supermarket goods, but also if some of them have a garden and grow their own vegetables and fruits. If someone has an apple tree in the garden, and someone else a cherry tree, they can exchange perfectly. Also if someone has pets it is useful. Many people throw away the green part from the carrots because they don’t use it. But if someone has a rabbit at home, it is perfectly useful, because they eat it with pleasure.

I think this is a good start to change his own consumption. It is easy, cheap, and you don't waste food.