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Taunusstein, 10. August 2004

„Between the harvest or production of industrial produced foodes and their consumption, there is naturally a more or less long period of time. The products must first be transported to a grocery store and stored until purchase. In the home, they are possibly stored again until they are eaten. So that the food doesn't spoil during this long process, they are preserved during production. Modern techniques make it posssible to preserve all of the important nutrition content and flavor. For this purpose, the INSTITUT FRESENIUS of Taunusstein recommends quality frozen products as opposed to „fresh produce“. The conditions to produce industrially conserved foods of the highest quality are flawless raw materials, a harvest at the optimal point of ripeness and processing within a few hours – with fruits and vegetables, often directly „at the plantation“.

Through shock freezing, temperatures between negative 30 and negative 200 degrees celcius inhibit the metabolism and growth of microorganisms, but only as long as the freezing is not interrupted. Because of this, the product should remain frozen for the entire journey between production and home use. Directly after the harvest, the raw materials are cleaned and purified and depending on the type of product, chopped and blanched. Blanching causes a better preservation of nutrition content. With deep freezing, flavor, appearance and nutrition content are largely conserved. The addition of chemical preservatives is neither necessary nor allowed. Frozen products have an expiration date.“

Source: Fresenius Institute http://www.institut-fresenius.de

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Because of their intensive color, berries are rich in anthocyanins and contain in addition, phenols. These secondary metabolites work together with vitamin C to explain the high antoxidant quality of berries, which protects human tissue cells. But what happens with these „inner values“ of berries after the harvest until sales in a supermarket or with freezing? To answer this question, scientists from the University of Glasgow and Aberdeen researched a type of raspberry after it was picked under the following conditions:

• within 3 hours
• within 3 hours, frozen at -30 degrees C
• after 3 days, stored at 4 degrees C (condition at arrival at supermarket)
• after 3 days, stored at 4 degrees C and afterwards 24 hours at 18 degrees C (an extra day of storage in the kitchen before consumption)

Interestingly, the amount of anthocyanins remained the same in all four groups, despite the different storage or processing methods. With the stored fruits, the phenol content even rose, because the metabolism process in the berries continued even after the harvest. However, the vitamin C content dropped in the fruits that were stored.

Especially interesting for the scientists was the effects of storage and further processing on the antoxidizing potential of the raspberries. This remained the same as with freshly picked berries, and didn't depend on the handling method.

So whoever likes to eat berries can keep frozen products on their shopping list the year round! The healthy qualities stay once and for all.

Source: www.5amTag.de

Cited studies:

Mullen W, Stewart AJ, Lean MEJ, Gardner P, Duthie GG, Crozier A Effect of Freezing and Storage on the Phenolics, Ellagitannins, Flavonoids, and Antioxidant Capacity of Red Raspberries J Agric Food Chem 2002,50,5197

Kalt W, Forney CF, Martin A, Prior RL Antioxidant Capacity, Vitamin C, Phenolics, and Anthocyanins after Fresh Storage of Small Fruits J Agric Food Chem 1999, 47, 4638-4644

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Excerpts from Albert Vollmer's speech to the Zerokraten Club on May 4, 2002 in Budapest

The freezing technique is also developing rapidly. We've really gone a quantum leap, so to speak, in the freezing process. Freezing has reached a very new dimension. And the freezing sensation has become everyday, we don't even really notice it. For about 20 years now, there's a whole group of people living among us, healthy and happy, thanks to the existence of freezing, because they grew from an egg that was frozen! And the „artificial“ insemination via frozen sperm cells is, so to speak, already a matter of course, routine in doctor's offices. It's become so everyday that people already talk about „freezer dads“.

You know all of the current catch phrases in biology and medicine: Cloning, stem cells, research on expectant life and so on ... This is an enormous event in public consciousness – with an enormous side effect for frozen foods. In this context and in public discussion, something happened that had huge consequences for freezing technology and especially for frozen foods. Through scientific leaps in research, freezing is commonly accepted as the best process to preserve life. Everyone takes it for granted that not only plant and animal cells, but also human cells and embryos are stored in freezing compartments at negative 196 degrees and remain healthy and fully active. And that is really a fantastic development.

Fantastic freezing perspectives

This scientific, medicinal advancement for the direct improvement of the quality of human life in connection with freezing technology is already taking on concrete forms in daily life. Today, possible future uses are being thought out: „When your child is born, freeze stem cells to help fight disease – you can give your child a second life“ the company Cryo-Care in Köln promises. Similar to Vita 34 in Leipzig, they combine a parents' worries with the current discussion about healing stem-cells to provide a service for the future: At the birth of a child, they freeze umbilical cord blood that would otherwise be thrown away. The stem cells found in the blood can perhaps be used in 20 years as a therapy for disease. A space in one of the company's nitrogen tanks costs between 1,300 and 3,300 euro. When parents start to think about this, it is very difficult to forget. Anthony Ho from the University of Heidelberg claims that „ the probability that a child will at some point need his own stem cells is so sm all that it doesn't make any sense to freeze them“. This criticizm is quickly brushed aside by parents and by reality. No wonder, because even experts succumb to fascination over stem cells. Anna Wobus from the German Research Society: „I would freeze cells of my own children, if I were in this situation“. Of course, naturally, because you can never be sure...

This concept could actually work some day. There is also a particular advantage: with stem cells from the umbilical cord, there isn't an ethical discussion as with embryonic stem cells.

New phase in quality of life through freezing

or let's think about the modern Noah's ark, the „frozen zoo“, where all types of animals are saved from extinction through a liquid nitrogen tank (we discussed this thoroughly in tk-report 5/2002 on page 6). We've reached a level in freezing technology in this area where people see cloning from an entirely diferent viewpoint-- cloning becomes an ethically justifiable method for saving different species.

With this, we are entering an entirely new phase in freezing. Until now, we have managed to keep cell the cell walls of plants and animals intact through quick freezing. We all know the explaining cell diagrams – unbroken and without sharp ice crystals. With this it is possible to keep the freshness of the cell in its original condition – the basis of the success of freezing preservation in the first phase of improving human quality of life on the table and on the plate.

But now we have come another huge step through advances in technologiy and science. With the super-freezing method we don't just keep cells intact in their inside and outside form at negative 196 degrees celcius, but even the vital functions at the nucleus of the cell are preserved. This is sensational! We haven't really arrived at „life“ -- the hand of God is still standing in between – but through freezing, on the nucleus that is directly connected to Life. And that is a noteworthy event! Through this, the improvement in quality of human life through freezing reaches a new, fantastic dimension.

This is tremendous, because the statement of the good Birdseye from the beginnings of frozen foods -- „these frozen peas or this cod filet is like it's fresh“ -- is extended by a huge leap: „Freezing technology is able to preserve life“. We haven't even begun to realize the potential of the freezer and its importance. Until now, we have only needed „dead“ cells that are necessary for our nutrition, frozen them, and stopped them from spoiling – whether with fish or peas. But now, we're actually able to take living cells (egg cells and sperm, etc.) and preserve them through freezing. This is a completely new dimension. Until now, we have preserved freshness as best as is possible-- this was already a real sensation and an enormous advancement in food conservation. But now we can even preserve the life in the cells! This is such a unique and sensational event that we still have to really understand it.

The message from us freezers is: We are unique ... ! There's nothing else like the freezing industry! This gives us a unique position at the top of all other preservation forms. For us, there is nothing that water can't do. We've written it many times: If there has ever been proof for the unexcelled quality of freezing preservation, then this is it. There isn't any better proof for the abilities of freezing than the preservation of all natural properties. If the highest level of life, a fertile animal or human egg cell, an animal or human embryo can be frozen and thawed after storage (even after many years!) and lives on and grows to a healthy animal or person, then this is the most convincing, most unique process. This is the unbeatable proof that freezing is the most advanced and best method for long term preservation and conservation of all original natural properties. It's not possible with any other method of conservation – whether drying, salting, smoking, chemical, radiation, aeration, steriliza tion, or extreme heating – with no other method is something at this level of perfection even close to being possible. If something this unique and impressive is possible with the highest form of life, then we don't even need to talk about the topic of quality and preservation of the natural freshness of a cod filet, a pea or a chicken. This exasperating topic that has kept us busy so often in the past is finally no longer an issue.

Trust in freezing

Naturally, we are at the beginning of a very promising development. But what we also see: Freezing and frozen foods have a wonderful perspective for the future! We shouldn't get caught up in the ethical-moral discussion in connection with new research on developing life, on the human embryo, and the problems with stem cells and cloning. We don't directly have anything to do with it, so we shouldn't worry about it. With our freezing process, we are just helping bio-tech research – completely necessary, but just a medium.

And surprisingly, the public has also registered this as understood: Freezing as a medium for research stands completely seperate from the firing line of this discussion. The trust potential here is a benifit for us in the freezing industry. We have to take this one-time opportunity to let the public know about freezing as a method to improve the quality of life! Because only freezing can accomlish this. We are the freshness and life preservers per excellence!  

But we should also make it clear that the advancements that we have reached so far have only been possible because the users of frozen products have done this as a matter of course and have believed in the freshness preservation that our method offers. The success of frozen foods on the dinner table is the father of medical science advancements.

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