What's causing the metallic aftertaste in my Nutraloaf? Thanks to all of the wonderful help thus far, I've finally been able to make my Überfood. It's called "Nutraloaf", and is kind of like a meatloaf with a bunch of other stuff in it.

It has no real taste (not a problem) and the texture is a little mushy (I will try baking it longer in the oven), but the idea is I can simply eat this 3 times a day, every day, and not have to worry about making any other food. 

However, one problem is that I'm getting a metallic aftertaste. I don't know if it's the ingredients, or the fact that I used a normal oven instead of a convection/steam oven. 

This is the recipe I used.

2 oz Ground Beef
Brown off in kettle and drain thoroughly

4 oz Canned, Chopped Spinach
4 oz Canned Carrots, Diced
4 oz Vegetarian Beans
Open and drain all vegetables well

4 oz Applesauce
1 oz Tomato Paste
1/2 cup Potato Flakes
1 cup Bread Crumbs
2 oz Dry Milk Powder
1 tsp Garlic Powder or Flakes

Combine beef and vegetables. Gradually blend in remaining 
ingredients until well combined. Mixture should be stiff 
but moist enough to spread. Each loaf should weigh 1 1/2 
pounds precooked weight and be scaled to insure proper 
weight. Place mixture into a loaf pan that has been
sprayed with pan release and lined with filter paper.

Each loaf should bake at 300 degrees Fahrenheit in 
convection/steam oven for approximately 40 minutes or 
until the loaf reaches 155 degrees internal temperature.


It is a subtle aftertaste and it went away after I had a stick of Wrigley's gum. I would prefer to not have to chew Wrigley's after every meal, since I don't really like chewing gum. I'm sure a peppermint or buttermint would also help with the aftertaste, but would prefer to fix my nutraloaf recipe or cooking technique. 

So how can I remove this metallic aftertaste? Or, where can I even begin looking for what's causing it?
It sounds like most of those ingredients came out of metal cans, yes? Certainly the spinach and carrots, and I imagine the beans, tomato paste, and possibly the apple sauce? Canned foods do sometimes have a slight metallic taste, especially if you don't use them all at once and continue to store them in the can after opening it: (about.com)

However, I definitely wouldn't rely on this (or any other single recipe) as your sole source of nutrition. Even if it does include every one of the hundreds (thousands?) of nutrients your body needs in reasonable ratios (which is questionable), that still doesn't mean it's good for you. 

For example: if every meal you eat has lots of vitamin C and zinc, your body won't be able to absorb the trace amounts of copper it needs, since they interfere with each other. To be healthy, you need to mix up the nutrient profile of your meals.