Almost anything with water in it and not much fat. Fruit, vegetables, dairy, eggs, cooked meals, raw and cooked meat, candy and pet treats all work. Pure fats, oils, honey, jam and anything mostly sugar syrup do not, because there is no free water to sublimate.
The complete list, by how forgiving it is
| Food | Difficulty | Notes |
|---|---|---|
| Sliced strawberries, raspberries | Easiest | 12 mm slices. The batch to learn on. |
| Peas, sweetcorn, green beans | Easy | Blanch first, then chill fully. |
| Sliced apple, banana, mango | Easy | Thicker slices hide wet centres. |
| Cooked rice, pasta, beans | Easy | Spread thin. Rehydrates almost perfectly. |
| Candy | Easy, needs mats | Puffs dramatically. Silicone mats essential. |
| Whole or scrambled eggs | Moderate | Scramble or blend first; powders well. |
| Cooked meals, stew, chilli | Moderate | Trim fat before cooking. 15 mm layer max. |
| Cooked meat, shredded | Moderate | Lower fat cuts store far longer. |
| Milk, yoghurt, ice cream | Moderate | Works well; fat limits it to 2–5 years. |
| Raw meat | Harder | Longer cycle, often a second dry. Must be cooked after rehydrating. |
| Cheese | Harder | Grate or slice thin. A 2–5 year food, not 25. |
| Herbs, flowers, botanicals | Varies | Very fast; watch you do not over-dry. |
What will not work
- Pure fats and oils — butter, lard, cooking oil. No free water, nothing to sublimate.
- Honey, syrup, molasses — the sugar concentration binds the water. It will not dry and you will make a mess of the chamber.
- Jam and jelly — same problem as honey.
- Anything already spoiled — freeze drying preserves what you put in, including bacteria. It is not a rescue for food on the turn.
- Very fatty cuts — technically they dry, but the fat goes rancid and you have wasted a cycle.
The one rule that covers most mistakes
Fat is the enemy of shelf life, and thickness is the enemy of a finished batch. Trim the first, and keep loads to 12–15 mm. Overfilling a tray by a centimetre can push a 20-hour cycle past 30 hours, because the vapour from the bottom of the layer has further to travel.
Before your first batch
Slice at 12 mm, pre-freeze the trays overnight, and run the machine’s default fruit preset. Getting one boring batch of strawberries right teaches you more than reading three more articles.