Commercially prepared roasted almonds can contain oils, sugars and other preservatives that you can avoid if you roast whole almonds at home. Roasting whole almonds gives you the opportunity to omit any oils or seasoning if desired, a process also known as dry roasting. If you want to spice things up a bit, add your own amounts of salt, soy sauce or peanut oil to the almonds.
When dry roasting whole almonds, or roasting without seasonings, you need to spread them out on a flat surface, such as a baking tray, so they have plenty of room while roasting in the oven. If you'd rather use the microwave, you can arrange the whole almonds on a microwave-safe plate before roasting them quickly in the appliance.
If you're into seasonings, you have plenty of options. Anything goes -- it just depends on your personal preference. For instance, if you have 2 cups of whole almonds, you can toss them in 1/8 to 1/4 cup of oil -- such as olive or peanut oil -- before spreading on a plate or baking tray for roasting. Add 1/8 tsp of different seasonings to the oil such as rosemary, cumin, sea salt or pepper. The actual amounts depend on your personal preference. Or, you can toss the whole almonds in oil, roast them and sprinkle seasoning on after you remove them from the heat.
If you roast the almonds at a high temperature, they can lose some of their good fats. Instead of roasting them in an oven set at 177 degrees Celsius, use a much lower temperature of 71.1 to 76.7 degrees Celsius. Roast the whole almonds for 15 to 20 minutes, stirring about halfway through roasting time. If you prefer to use the microwave, cook the almonds on "high" for four to five minutes. Be aware that microwave roasting may compromise the nutritional value of the almond due to the high heat conditions.
If you place the homemade roasted whole almonds in a cool environment, such as the refrigerator, they will last longer. After the whole roasted almonds are completely cool, place them in an airtight container and put it in the refrigerator for up to two weeks.