I was wondering what the most eco-friendly high-starch food is — not per kg but per calorie — I am looking for something to eat large amounts of when hungry after my main meals. Thanks.
Grains and beans are staple foods as well as potatoes. My location is Melbourne, Australia.
Your location will have a big influence on what is eco-friendly since things grown where you are may require intense inputs not needed on other sites. Melbourne and surrounding areas, for example, have sandy soil and low precipitation, so require higher inputs of fertilizer and water than other places in general.
Also, investigation into your immediate foodshed area may reveal surprising sources of calories for little to no environmental impact. Perhaps there is a food common during certain times of the year that has a short shelf-life and is thus thrown out. A seasonal diagram for Melbourne is available here. You could enquire at your local grocer, or simply watch sales. When produce goes on sale, this may be because of an oversupply. The store may be putting this item on sale to try to sell what they can before they toss it out. Taken to the extreme, there is also "gleaning" or the gathering up of food items that others leave behind or throw away. This started on farming fields when people would follow the harvester, gathering up foods dropped on the floor, but in urban locations is known as dumpster-diving. Some grocers or restaurants will leave food somewhere for people to glean before it goes in the dumpster. I am not sure whether or not this is legal in Melbourne, but there is a facebook site for dumpster divers in your city here: https://www.facebook.com/dumpsterdivingmelbourne/
In short, if you really want to minimize your food footprint, you may want to look at varying your "extra calorie intake" to reflect seasonal gluts in what is available locally.
First approximation:
What is the cheapest starch? Use dry weight, or bucks per calorie.
This tends to maximize for the calories per acre of land used, and the costs to bring it to market.
It does not take into account externalized costs of farming: Soil loss, chemical pollution, habitat destruction.
So your next step would be to start with a list of cheap sources,then to look at how each is typically farmed.
So, for example, potatoes are cheap, but the chemical use for spuds is unreal.
Soybeans are high chemical users too.
Grains: Wheat, barley, oats are only moderate chemical users. I would give serious consideration to any of these three that you could buy organically, especially if you could buy whole grain at the farm gate. Look also for organic peas and beans.
As a starch source, oats is the highest yield per acre. Hulled oats are easily chopped into scottish 'steel cut oats' which have a fairly low glycemic index, so they stave off hunger longer.
This pattern could result in dietary issues. Most grains have protein but it is incomplete. If you are using this a supplement, fine, but if it's going to be a major part of your diet, look at mixing sources to get the right protein mix. Beans and either rice or corn work well. Possibly any legume combined with any grain. The vegan circle has good information about balanced combinations.
