Step 1Heat the oven to 350 degrees.
Step 2In a medium heavy-bottom saucepan, melt the frozen juice concentrate and bring to a boil over high heat. Boil rapidly until the liquid is reduced to about 1 cup, about 10 minutes. Remove from heat and measure three-fourths cup plus 2 tablespoons (7 ounces), discarding any remaining reduced concentrate. Cool to room temperature.
Step 3While the reduced concentrate is cooling, in a large bowl whisk together the bran, flour, baking soda, baking powder and salt.
Step 4In a separate large bowl, whisk together the buttermilk, concentrated reduction, oil and eggs until fully incorporated.
Step 5Pour the wet ingredients over the dry and gently mix together with a rubber spatula until thoroughly combined, careful not to over-mix.
Step 6Gently fold in the sesame, pumpkin and flaxseeds, coconut, granola and raisins.
Step 7Spoon a heaping one-half cup batter into each of 14 lined large (or jumbo) muffin tins. Bake the muffins, one pan at a time, in the center of the oven until golden-brown and the tops spring back when lightly touched, 20 to 25 minutes.
Step 8Remove and cool the muffins, still in their tins, on a rack.