If a muffin needs to sit on a shelf or counter for days or if it’s already sat in a warehouse for a while before making it to that shelf, it’s going to need a little help to stay moist and tender. To be fair, you’d probably need some help, too. That’s why a lot of commercial muffins are chock full of preservatives (via Belgoods Bakeware). Have you looked at the ingredient lists on the plastic 6-packs of muffins at your local grocer? There probably isn’t even an ingredient list on the ones in the self-serve, see-through counters at the convenience store, but rest assured it’s probably longer than you may want to see.
Even a muffin from a local coffee shop can surprise you. A blueberry muffin from Dunkin’, for example, includes mono and diglycerides, sodium stearoyl lactylate, sorbitan monostearate, polysorbate 60, gelatinized wheat starch, and carnauba wax to help things appear fresh. Meanwhile, the blueberry muffin from Starbucks is a fair bit more natural, with soy lecithin acting as a mild preservative (via SF Gate). The rest are ingredients you might use in your own homemade muffins.
Why is it important to limit high-processed foods? Foods with a lot of preservatives may potentially be linked to some chronic diseases, says Livestrong, though research into the links between preservatives and human health is still ongoing.