Freeze Drying

Pine Acres Nursing Home Freeze Drying

The following, presented as a public service by Pine Acres Nursing Home of Madison, NJ, is taken from a bulletin of Research Experiments & Innovations of Klamath Falls, Oregon, an outstanding nutritional supplement company that went out of business early in 1996 shortly after the demise of its owner, Dr. Victor Kollman.  The illustrations that accompanied the original article have been omitted.  Some significant segments of the text have been highlighted.Contents

What Is Freeze Drying [Lyophilization]?

Freeze Drying at Low Temperature (Cryogenic)

Freeze Drying at  High Temperature

Spray Drying

Summary of Drying Technologies

Microbiological Contamination

Finished Product Storage and Shelf Life



November 1995

Freeze-Drying Makes the Difference

by Victor Kollman, Ph.D.

We who have access to the vast array of existing modern technology have the power to use it to build a better, more healthy society; or, we can use it for destructive purposes thereby hurting/injuring others.  Nowhere is this more evident than in food and health technology.  In this article we discuss the almost unlimited potential of modern freeze-drying [lyophilization] technology to prepare foods and nutriceuticals having far superior nutritional quality to heat-processed food and food supplements (vitamins, minerals, protein, lipids and carbohydrates, etc.).  However, simply because a food or food supplement states on the label that it has been freeze-dried does not mean that it has ever been close to a cryogenic (low temperature) freeze dryer; or, that the product has any more food value than if it had been processed by conventional heating methods.

Yes, untruthful labeling is fraud and this practice is rampant in the so-called health foods business.  Buyer beware.  Read this article before you make a purchase.


What is Freeze-Drying?

Freeze-drying or lyophilization is a method used to dry a material such as herbs, vegetables, milk, or algae, etc. in a frozen state under high vacuum so that ice or any other frozen solvent (solublizing liquid) sublimes rather rapidly and a porous solid containing about 3% moisture (water) content remains.  Sublimation is the process of causing water or some other solvent to pass from a solid state to the vapor state without passing through the liquid state.  Many pharmaceutical products and most of our nutriceutical products are purified by this process which is accomplished by freezing the material (in water) to be processed and then cooling it to about -20°F in the freeze-drying chamber.  A vacuum is then applied to the freeze-drying chamber and the amount of air inside the chamber is reduced to about the amount of air you would find on. the moon (essentially none).  When a full vacuum has been achieved, heat is slowly applied to the material to be freeze-dried.  Heating of the product material is done by passing a warm liquid through stainless steel coils located just beneath the shelves on which the material being freeze-dried is located.  This warms the frozen material and the frozen solvent gradually passes from the solid state to the vapor state.  The vapors of the solvent are condensed back to the solid state (ice) on condenser plates located inside the freeze- dryer.  The condenser plates are cooled to about -80°F using special freon-type coolants and compressors, similar to those used in home refrigerators and freezers.  The sublimation process continues until the product is dry (3% moisture content).


Low Temperature (Cryogenic) Freeze-Drying

There are two types of freeze-drying methods in use throughout the United States.  One of these methods uses high temperatures (up to 225°F) and the other, which produces superior quality products, uses low temperatures (highest process temperature is 14°F/10°C).  Shown in the four photograph pictorial display on the following page is a Model 24P Stokes Cryogenic Freeze Dryer. This particular freeze dryer has been modified to cool products to less than -40°C (-40°F). A brief description of the freeze dryer is included with the pictorial display.  [Illustrations have been omitted]

In a typical freeze-drying operation the rate of drying (sublimation) is controlled by the temperature of the heating liquid which in turn raises the temperature of the material being dried.  Within certain limits the higher the product temperature, the greater the rate of drying.  In low temperature (cryogenic) freeze-drying, the shelf temperature is never increased at a rate greater than the capacity of the vacuum system to maintain 150 millitorr (0.15 millimeters of mercury) and the freon system to maintain -76°F on the ice condensing plates.  The time required to dry the product is from 4 to 6 days.  However, the results are worth the extra cost and time.
Some of the benefits of Cryogenic Freeze-Drying:

  • Insures maintenance of molecular energy and integrity (same or better than the living state).
  • Maintains enzymatic activity.
    Limits cell rupture to insure cells are viable when rehydrated (suspended in water).

  • Guarantees the activity and assimilability of vitamins, minerals, lipids and protein, etc.

  • Lengthens the refrigerated shelf life.

If the original product that was introduced into the freeze dryer was free of bacteria, yeast, mold, and fungi, there is no reason for concern over pathogenic products.  However, we have each of our freeze-dried products analyzed for salmonella, staphylococcus, mold, yeast, fecal coliforms and general aerobic bacteria to be certain that none are present and that no harmful enterotoxins are lurking around to make you sick.

High Temperature Freeze-Drying

High temperature freeze-drying technology is employed by essentially all commercial and private companies who claim to be “freeze-drying” their products, with the exception of those who culture friendly bacteria.  High temperature freeze-drying can also be referred to as cooking under low vacuum (2.5 torr = 2.5 millimeters of mercury) while heating the product temperature in the chamber to temperatures that can reach 225°F and above.
Use of high temperatures has three advantages:

  • Cuts the time for drying from 4 to 6 days to 48 hours.

  • Reduces the cost factor by about four.

  • Kills some (but not all) unwanted/harmful microorganisms.

During the drying cycle (48 hours) the product temperature is ramped (increased) via computer commands to 225°F.

  All biological enzymatic activity is usually lost between 110°F-122°F and the biological quality is permanently destroyed.  Further, in high temperature freeze-drying the final moisture content is usually 10% or higher.  The result… wet spots in the partially dry product promote the growth of various microbes (pathogenic and non-pathogenic).  Then, the processor must bake (at higher temperatures, greater than 225°F) the partially dry product to sterilize it in order to sell it to an unsuspecting buyer who, in all likelihood will experience some undesirable side effects from overloading the gastrointestinal system with dead microorganisms.  This practice is used by nearly all health food businesses, particularly those who sell and distribute algae products, both of domestic and foreign origin.

When high temperature freeze-drying is used, if there is chlorophyll present in the product, the chlorophyll molecules will lose their magnesium ions and be degraded to pheophytin.  Pheophytin is a bluish- black waxy pigment that is dark olive brown in solution and differs from chlorophyll by replacement of the magnesium atom in the molecule by two hydrogen atoms.  Pheophytin has a bitter flavor.  High temperature freeze-drying causes carbohydrates to carmelize (char), producing a burned smell.  Further, lipids, fatty acids, and proteins lose their biological integrity (original quality before drying).  The final product obtained by high temperature freeze-drying generally has a burned smell, is darker in color than the natural fresh material, has markedly less nutritional value and has lost most, if not all, of its high structural energy due to molecular configuration which was acquired during growth (synthesis).  The product is less energy-dense.  When the product is eaten, the consumer is left with little more than the “seller’s hype” which convinced him/her to buy the product in the first place!  

Shown in the table below is a summary comparison of Low Temperature Freeze Drying versus High Temperature Freeze Drying. It may more easily help in perceptualizing the dramatic differences between REI’s LTFD (low temperature freeze-drying) technology and the quality of products being sold by entrepreneurial companies who use fast and dirty processing procedures to rush their so-called premium quality products to market.

Comparison of Low Temperature Freeze-Drying (LTFD)
and High Temperature Freeze-Drying (HTFD)

Comparative Low Temperature Freeze-Drying High Temperature Freeze-Drying
Product quality High to superior Low to not acceptable
Need for post freeze-drying sterilization No Almost always
Sterilization temperature Not applicable Greater than 225°F
Starting temperature of product  -40°F to -20°F 32°F (freezing temperature of water
Final temperature of product 14°F (-20°C) 180°F-225°F
Dead microbal contamination in the dried product Not detectable on a general basis Generally highly contaminated with pathogenic and non-pathogenic microorganisms
Enzymatic activity High Very low to none
Natural molecular configuration and biological activity High None
Regular bacteriological testing of dry product Yes Usually none
Freeze drying time 4-6 days 48 hours (2 days)
Relative cost factor 4 times more expensive than HTFD Lower cost
Product shelf storage temperature range -5°F to35F 75°F to 85°F (room temperature)

Spray Drying

A lower cost method of drying some products such as milk, infant milk substitute formulas, whey, egg whites, etc., uses the technology of spray-drying.  In this technology a fine mist of solublized product is introduced into a large conical chamber where it comes into contact with air that has been heated to about 300°F-500°F, depending on the product being dried.  The hot particles fall from the top to the bottom of the conical shaft where they are recovered in the form of a dried powder.  The advantage of spray-drying over high temperature freeze-drying is that a secondary sterilizing heat treatment is not required to kill contaminating bacteria, yeast, mold, fungi and other undesirable micro-organisms.  The initial air temperature will kill and degrade the toughest of microbes.  But the contaminating organisms (killed) are still present in the products you consume. Powdered milk is one of the lowest quality products on the market today, simply because of the contamination that is present in the milk prior to spray-drying (junk goes in and worse junk comes out with a shelf-life that is almost never ending).

The controversy between advocates of spray-drying technology and high temperature freeze-drying technology has been raging for as long as the two methods for removing water from biological materials have been in existence.  Actually, there has never been any question regarding the preferentiality of the low temperature freeze-drying technique, as it is used universally by scientists and industry to preserve and maintain biological viability of cells and enzymes.  For example, people who grow and process friendly bacteria (L.acidophilus and L.bifidus) use low temperature freeze-drying exclusively.  Why?  Because their products are not initially contaminated by foreign microorganisms, and they maintain cell viability upon rehydration (adding water back to the dry cells).  The reason that spray-drying continues to be popular is that it can be done much less expensively than high temperature freeze-drying, has a higher through-put volume of products per hour, and reduces to a greater degree the chance of live pathogenic and non-pathogenic contaminants showing up on the shelves of the consumer.

Most food grade algae (foreign and domestic) are spray-dried or are processed using high temperature freeze-drying.  Shown in Figures 1 and 2 [Illustrations have been omitted] are contaminated cultures of the green algae known as Chlorella.  Chlorella is a popular import product usually grown and processed in Japan or Taiwan.  The Chlorella cells, which measure 2.5 to 5.0 micrometers are separated from the aqueous growth. medium by centrifugation.  The packed cells are then washed and spray-dried in the spray dryer (drying temperature 300°F-500°F).  Spray-dried cells of Chlorella were examined by Liang-Ping Lin (Dept. of Agricultural Chemistry, National Taiwan University, Taipei, Taiwan, R.C.C.) using a scanning electron microscope.  After spray-drying, most of the particles (clumps) of Chlorella measured 40-85 micro-meters in diameter (Figures 3 and 4)[Illustrations have been omitted].  At higher magnifications, it was shown that the sphere-like structure consisted of many thousands of single Chlorella cells (Figure 5).  At greater magnification (Figure 6) it can be seen that each cell has piled one on the other and clumped together.  The ash material, which can be seen attached to the cells, is probably a product of cell degradation due to the heat treatment at elevated temperature (300°F-500°F) of the hot air inside the dryer.

[Summary of Drying Technologies

The main criterion for obtaining a pure product from any drying process is to start with bacteria-free raw materials and then reduce the moisture content to about 3% water.  Correct storage temperature before and after the drying process cannot be ignored.  Depending on the nature of the product it may require storage at refrigerator temperatures (35°F) or freezer temperatures (0°F).  Some materials require storage at -40°F, such as semen.

Heat from any drying process is the major cause of product degradation.  Heat causes the cells to clump together in large masses or to become excessively dehydrated making digestion of the product difficult.  Further, charring of the carbohydrates and partial carmelization of cell wall constituents inactivates digestive enzymes making the cell virtually impenetrable and thus the “burned” product passes through the intestine with little or no nutritional benefit.  The same denaturation process occurs when any algae (Spirulina, Aphanizomenon, Anabena, Anacystis, etc.) or milk products are subjected to the harsh elevated temperatures encountered in high temperature freeze-drying and spray-drying.  The most expensive of the drying processes, cryogenic (low temperature) freeze-drying, maintains optimal biological activity of the dried material and maximizes the true energy potential that can be derived from consuming the nutritional product.  Surrendering product quality for economic leverage is not a consideration at Research Experiments & Innovations.  That is why we are the only company using cryogenic freeze-drying methodology exclusively to prepare our products.


Microbiological Contamination

Would you eat a food product or supplement if you knew it was contaminated with one or more of the following microorganisms: yeast (Candida), mold, E.coli, salmonella, staphylococcus, streptococcus or pseudomonas?  Would it make a difference if you knew these organisms were dead but still present in the food you are about to consume?  Would you think that the company selling these contaminated products was a highly reputable outfit, deserving of your support?  If you knew there were about 1,000,000 dead micro-organisms in a single gram of Blue-Green Algae (aphanizomenon) harvested from Upper Klamath Lake or its effluent subsidiaries would you eat or sell these algae products?

Your answer is no, right?  Well, that is what’s happening in the three major algae producing companies selling their so-called premium quality products harvested from Upper Klamath Lake.  Each of these companies has a myriad of problems with extensive microbiological contamination that accumulates in their harvesting procedures, handling techniques, freezing technology, high temperature freeze-drying procedures, post sterilizing ovens, final moisture content, and packaging, storage and shipping protocols.

A standard microbiological analysis, performed by an independent laboratory, of Aphanizomenon flos-aquae (blue-green algae) that was harvested and processed correctly yielded the following results:  


Standard Plate Count (CFU/g) <100
Presumptive Coliform (MPN/g) <3
Confirmed Coliform (MPN/g) <3
Eschericha coli (MPN/g) <3
Yeast (CFU/g) <10
Mold (CFU/g) <10
Salmonella per 25g Negative

CP Staphylococcus

(CFU/g) <10
KF Streptococcus (CFU/g) <10
Pseudomonas (CFU/g) <10
CFU=colony forming units;
MPN=most probable number
Note: For the tests performed, the test results are all at the lower limit of detection for each specific organism.

The microbiological analysis obtained by us for Aphanizomenon flos-aquae is not simply a good analysis from a single collection.  Within experimental parameters this is what we have come to expect because we have been running these analyses since 1976 (almost 20 years) with consistent results.  The blue-green algae for the sample was analyzed after it had been cryogenically freeze-dried.  It had not been subjected to post-sterilizing temperatures and therefore did not contain a load of dead microorganisms.

Finished Product Storage and Shelf Life

The shelf life of a substance is the period of time during which a material may be stored and remain suitable for sale. The more environmentally perishable a substance, generally the shorter will be the shelf or storage life.  For example, we know that lettuce, spinach, chard, cabbage, etc. must be stored at 35°F in order to partially maintain their “field” quality and also to prevent spoilage.  These materials have short shelf lives.  On the other hand your grocery retailer puts spray-drled milk on the shelf, where typical storage temperatures are greater than 70°F, and then forgets about it until the product is sold or the boxes need to have the dust removed.  Spray-dried milk has such a long shelf life because even a hearty microbe doesn’t recognize it as a worthy food source.  Yet, I know numerous women who feed this junk to their families and expect their children to grow up normal, healthy, and allergy free.

Have you ever gone to the typical health food store or nutrition section in a food store or pharmacy and looked at the products that are kept in cold storage (35°F or less)?  Many do not even have a cold storage section and those that do, keep far less than 1% of their total inventory refrigerated.  Refrigerated items may include natural ice cream, tofu, natural soda pop, natural yogurt, raw milk, bacterial cultures, goat cheese, and perhaps some frozen meats – but not usually.

What does it mean when over 99% of the products labeled as nutritionally superior and located in the health food/nutrition section of a pharmacy or food store, require no refrigeration to maintain their freshness? You guessed it, they are just as dead as the rest of the overly processed foods and nutritional supplements in the store. You get the point, right?

Not long ago I telephoned one of the companies that sells Aphanizomenon (blue-green algae) harvested from pristine Upper Klamath Lake.  After I had inquired of the secretary about the availability of the product, I was transferred to a company representative who informed me that I could purchase the product and would also save money by becoming a distributor.  Naturally, I went along with the game in order to get for my research project a representative sample of the product being sold.  I inquired about their method of storing the products prior to shipment.  Of course, I was assured that refrigeration was not necessary due to the superior antioxidant properties of the blue-green algae and that they were “freeze-dried”, but that, nevertheless, to be certain that their products were superior to those of others selling the same algae, theirs were “kept on the north side of a cool building”.  This did not really impress me.  The sample of blue-green algae arrived in about one week and underwent testing: the material had initially been subjected to high temperature freeze-drying, the chlorophyll had completely degraded to pheophytin (bluish-brown degradation product), it had a burned/rotting odor, was loaded with microorganisms, and was not safe to be consumed by humans or animals.  All algae products, in order to be safely preserved must be kept under constant cold storage.

At Research Experiments & Innovations all of our products are refrigerated or frozen.  This is done to preserve the “living quality” of the material. We want you to get all the benefits our products offer, so we keep them fresh and cold, because we feel you should get what you pay for.  We sell quality, not hype.  If the nations health food businesses do not start policing their counterparts, then we as a whole are doomed to increasing levels of pressure from both State and Federal regulatory agencies.



At R.E.I. we use only cryogenic freeze-drying procedures to insure that you get the optimal energy release when you consume our ultra pure pristine products.  All of our product line contains “living molecules” that have high-energy crystalline structures that can release centripetal energy (building energy/anabolic energy) into all parts of the body.  This helps strengthen the life force of the consumer.  There is an increase in the coherency of body function.  After the crystalline molecules release their energy of conformation, they can then be digested and their caloric energy used to synthesize required cellular components.  The net result is an enhanced quality of life and an increased sense of wellbeing (reduced entropy/randomness in the brain).  You feel healthy and that means you feel good.

In summary, we offer a complete line of ultrapure products that are free of microbiological contamination, enterotoxins, heavy metals, other toxic elements, pesticides and herbicides. Our products are all synthesized in a manner that helps to strengthen the immune system rather than placing a heavier burden on an already over worked part of most everyone’s body.  And, the best part is that our products contain living molecules that have as much or more contained energy than the original bio-materials.  That’s a fact that no one else can lay claim to.  At R.E.I. you get the facts right from me, and not from some misinformed upliner who has been duped by company officers to spew forth propaganda (true or false) just to get you to buy their products.  

[As mentioned at the top of the page, Dr. Victor Kollman and his company, Research Experiments & Innovations, ceased to exist in early 1996.]