Store pancake dough in the refrigerator for up to four days. Practicing the two-hour rule is also advisable with pancake dough, as it contains dairy products. Expert Home Tips says that pancake dough containing dairy and flour should last two to four days in the refrigerator. If you don't have time to weigh the ingredients and prepare the pancake mix in the morning, you can go ahead by preparing the ingredients and storing the dough for pancakes or waffles overnight.
Pancake mixes have a shelf life of 6 to 12 months, but you can safely use them for months (or even years) after the expiration date on the label. While most of the dry ingredients in a normal pancake mix can last for years after that date, baking powder can't because it loses potency. Of course, it's not that the mix goes bad or that the pancakes are soft after a few days after the “expiration date”, but storing it for another year might not work the way you'd like. You may have noticed that your recipe tells you to let the pancake dough rest when making pancakes.
I recommend a similar method when working with old cake and brownie mixes, although when working with them, you can't afford to test a small amount of the mix to see how much help it needs. You should store pancake mix the same way you store other dry ingredients used in cooking and baking, such as flour, baking soda, or cake mix. While it's perfectly safe to store and use pancake batter (if done correctly), the results may not be as fluffy as the day the mix is prepared. Finally, every pancake mix is different and I can't guarantee that the pancakes will rise properly after adding that amount to the dough.
So, while a five-year-old mix may be perfectly safe to use, the pancakes you make are likely to be dense and flat. If you want to make pancakes in a short time, instead of relying on the mix, you can make the pancake dough and freeze it.