I used to store Ensure, or Nutren, or similar enteral nutrition products as part of my long term food plan. But they expire too quickly (in my mind) for the cost.

But they do offer a full nutritional spectrum, and you can buy Glucerna or other products specific to your condition (diabetic, pediatric, etc) if necessary.

Carnation Instant Breakfast is essentially a powdered version of the Nestle enteral products, and gives you 5 grams of protien if not using milk, 13 grams with milk used (according to their website).

The other upside to liqid nutrition is the ease in consumption.