Freeze Drying: Essential and Nice-to-have Tools and Supplies

freeze dried food

Congratulations! You are now the owner of a new freeze-dryer; or you are ready to make the purchase! While the freeze dryer itself is a major investment in food preservation equipment, you will want to make certain you are prepared with a few other items that will assist you in putting the dryer to work right away.

Utah-manufactured Harvest Right freeze-dryers include some of the basic necessities for freeze drying. Currently, their website states that in addition to the freeze dryer, the purchase will also include some supplies. If another brand of freeze dryer is purchased, these supplies may vary.

Included with Purchase

Vacuum pump (oil), vacuum pump oil, oil filter, stainless steel trays (set of 4), guide to freeze drying, 50-count Mylar bags, 50-count oxygen absorber packets, and an impulse sealer.

While a few of items below are considered essential, others may be considered desirable additions depending on how your dryer is set up in your home, how frequently you plan to use it, and the priority method for storing the freeze-dried foods.

Essential

  • Designated spot for the unit away from the main flow of traffic in the home. Some homes may have a separate room inside such as a large closet or pantry/food storage room. Others tend to find space in the garage to set up the unit. How much counter space does it require? A standard/medium-sized dryer is 30” tall x 20“ wide x 25” deep. (Harvest Right). The countertop, table, or cart must handle weight of approximately 115-125 lbs.
  • Designated electrical outlet is important to have sufficient electrical power to operate a freeze dryer. For a large freeze dryer- a dedicated 20-amp circuit is required (highly recommended) but a standard 110-volt outlet works fine for small to medium/standard dryers. Use of extension cords or power surge/strips is discouraged.
  • Vacuum pump is required for the freeze-drying process, whether an oil pump or oil-less pump is purchased. A basic oil pump is included with each purchase. However, purchasing a pump requiring less hands-on servicing will be a separate expense and purchased in addition to the cost of the freeze dryer so plan ahead to include this item. Costs vary widely and may require additional planning for financing the purchase: Basic Oil pumps generally cost under $200 when purchased separately. This type of pump requires draining and filtering the oil on a regular basis while the oil-less pump costs around $1,700 and requires occasional cleaning (following processing approximately 10 batches).
  • Bucket (A 5-gallon plastic bucket works well) to contain extracted water/liquid extracted from food that turns to ice during processing. As the DEFROST cycle is selected following the freeze-dry process, the ice will melt and drain from the bottom of the freeze dryer through a tube and into the bucket.

Nice to Have

  • Heavy duty cart with wheels is nice to have or essential depending on where the freeze dryer will be stored vs. used. If it will be moved to a different location each time it is used, a heavy duty cart will be helpful. Consider purchasing one large enough to hold the vacuum pump on the same level as the dryer and one that has a lower shelf to store supplies and tools.
  • Extra set of Trays will benefit those who have larger quantities of foods to freeze-dry. The extra trays can be filled, and then frozen so they are ready to put into the dryer following a defrost cycle of the previous batch.
  • Silicone mats offer protection for the stainless steel trays and make it easier to remove some foods that tend to have juicy textures that make food stick to the metal trays.
  • Mylar bags and/or self-sealing freezer bags make storing freeze-dried food simple and in quantities that will be easily used for individual and family snacks and meals. However, it may work just as well to use sealable containers with Snap-On lids. Others may also wish to obtain a metal can sealer and select #10 (approximately 1-gallon) food grade metal cans for storing larger quantities.
  • Oxygen absorber packets remove any remaining oxygen inside a sealed package. A single 300CC size absorber packet should be sufficient for a 1-gallon Mylar or plastic self-seal bag. This is a good option for anyone who does not own a vacuum sealer.
  • An Impulse sealer or vacuum sealer becomes optional when oxygen absorbers are used. Impulse sealers create a sealed seam for Mylar bags. The bags may be opened and resealed beneath the original seal line. However, this sealer does not remove remaining oxygen. On the other hand, a vacuum sealer will suction out remaining oxygen and then can be sealed. Some users prefer to include an oxygen absorber packet just to err on the side of caution.

Miscellaneous

  • Rubbing alcohol- Inside oil-less pumps there is a buildup of fine metal shavings and residue that should be removed periodically. This is done by slowly pouring approximately ¼ cup of rubbing alcohol through the hose which is disconnected from the freeze-dryer while the pump is on.
  • Large metal spatula/scraper- Sour cream, yogurt, eggs, and other liquid foods will freeze-dry into one solid mass. For easy removal and to avoid having the food crumble before it is placed into pouches or bags, a large scraper can help loosen the food from the tray and large pieces removed.
  • Hot pads/mitts- If the freeze dryer completes the cycles and food isn’t removed soon after, the dryer will freeze the food and hold it below zero until the user touches the “DONE” pad on the panel. The trays will be extremely cold and hot pads may be useful to remove the food to avoid freeze-burning the skin.
  • Plastic tote- For organizing supplies, choose a size that will either fit on the same cart as the freeze dryer or that can be stored nearby.
  • Extra pump oil, if applicable- While filtered oil may be used at least one additional time, having an extra 32- 64 ounces on hand is a good idea.

example of drain tubing
Example of drain tubing running into 5-gallon bucket on lower cart shelf to catch liquid during the defrost cycle.

 

Note: Most of these items are featured on the harvestright.com website. By browsing the products and comparing similar items from other manufactureres (e.g. Mylar bags and oxygen absorber packets) the buyer can determine which itmes to purchase through Harvest Right or another company/business.

Author

Kathy Riggs, Extension Professor

 
 
 
 

Related Research

Events