Lunch for backpacking usually is an on-the-go snack. You perform better by nibbling all day instead of sitting down for a big lunch. I use 1-oz cheese sticks (the individually wrapped sticks keep better than a chunk of cheese), nuts (I prefer almonds or honey roasted peanuts), dried fruit (my favorite is Mango slices - get at Trader Joes), and jerkey. I get really tired of trail bars but they are fine for a short trip - buy them in the natural food section, or exercise food section of regular grocery stores. I find that a sport drink like Cytomax is good if I will be hiking in hot condtions. If you cannot find Cytomax, powdered Gatoraid is available in most stores. I prefer Cytomax because Gatoraid has lots of sugar. This is not a "recovery" drink, but rather keeps your electrolytes in balance as you sweat.
Read the label on freeze dried dinners. Many contain a lot of "textured vegetable protein". You can buy TVP in the health food section of grocery stores in those big bins, for much less. Put a tbs in each dinner and breakfast for added protein. Same with powdered milk.
I always take margarine or olive oil. You have to re-pack it. I use those screw-top plastic food storage containers. An old plastic peanut butter jar works too.
Nothing wrong with taking a deli sandwhich for the first day. Or an apple. Get a sandwhich without mayonaise or eggs just to stay safe in case it gets hot. Tortillas with bean dip make a good first day lunch too.
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