It is the
straightforward requirement of the consumer to be supplied with Aloe
Extract which is genuinely from the Aloe plant and which has not been
contaminated with anything else. The consumer can come to realise that
some preservatives are needed, otherwise the Aloe vera Extract cannot
possibly be stabilised for distribution and marketing.
![photograph](bot171_files/plaskett.jpg)
About the
Author Dr Lawrence G. Plaskett obtained his
doctorate in biochemistry at the University of London in 1960. Lawrence
Plaskett is the Founder and Principal of a College of Nutritiona and
Nutritional Medicine has trained some 1,600 students in the last 14 years.
He is a respected and recognised innovator in the field of mineral
nutrition. He is the author of many articles on Nutritional Medicine
dealing with individual nutrients and their relationship to certain named
clinical conditions. He has completed a monograph on the Health and
Medical Use of Aloe vera, plus a series of biomedical newsletters on Aloe
vera, Phospholipids and Proanthocyanidines. He consults with US and UK and
European companies on Aloe vera and has a working connection with the
International Aloe Science Council of Dallas, Texas. He has completed
monographs on Nutrition and the Menopause on the medical use of
nutrients. Dr Plaskett can be contacted care of
Biomedical Information Services Ltd, 23 Chapel Street, Camelford, Cornwall
PL32 9PJ, Tel/Fax: 01840 212782. Copies of his newsletters are available
from this address.
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It is the straightforward requirement of the consumer
to be supplied with Aloe Extract which is genuinely from the Aloe plant
and which has not been contaminated with anything else. The consumer can
come to realise that some preservatives are needed, otherwise the Aloe
vera Extract cannot possibly be stabilised for distribution and marketing.
So far as that is concerned, he or she will always want to see the amount
of preservatives kept down to the minimum needed and will also want to be
sure that only the most benign preservative compounds are employed. So far
as any other additives are concerned, the consumer would usually rather be
without them, but, where they are used, the most important thing is that
full information should be given so that it becomes clear to the consumer
that certain named brands of Aloe are either diluted with water or
adulterated with cheap non-Aloe solids, enabling rational purchase
decisions to be made. The tendency, which has long been rather rife in
this Industry, to sell very diluted products, or to sell products
adulterated with cheap non-Aloe additives, without any clear label
declaration, is to be deplored. The
essentiality of the preservatives is an important matter for the consumer
to understand. If 100% pure Aloe vera juice was to go out for distribution
it would rot or ferment long before reaching the point of sale. That means
that any liquid product on the market which claims to be "100% Aloe vera"
cannot be genuinely quite 100%, although it can be very nearly so. And any
liquid product which claims "no preservatives" has got to be wrong unless
it were canned or otherwise sterilised or was on very short term
distribution – rather like fresh milk. The Industry is based almost
entirely upon stabilising the product for the market and hence the
preservatives are unavoidable. There is also
the practice of describing a product as being "made with 100% Aloe vera".
This will usually mean that some percentage of the total product will be
composed of 100% Aloe vera, but there will be other ingredients as well
and the Aloe vera component may be quite a small amount. This could, and
does, easily mislead the uninitiated. This
field is one where the consumer understandably feels powerless because the
laws which govern the sale of Aloe vera products in most countries are
wholly inadequate to ensure that the consumer receives a good quality
product. The consumer’s recourse to Law is therefore usually going to
avail him or her nothing. In the UK the Trades Descriptions Act may seem
to provide blanket coverage by legislating against the false description
of products generally. However, in practice the regulatory agencies are
inhibited by the lack of any nationally recognised standards for Aloe. In
the absence of such statutory standards governing e.g. the water content
of Aloe products, it seems that any effective action is unlikely. This is
a situation which leaves the policing of dishonest or misleading Aloe vera
products largely to the Industry itself. That is difficult – inherently so
– since it is the Industry itself which has been offending in these
matters. Fortunately, there are operators in the Industry who fully
realise that the Industry itself, more than anything else, needs the
setting of standards. The Industry and the product can be brought into
disrepute if the public is repeatedly charged good money for false or
debased products. The remarkable qualities of Aloe will come to be seen as
a myth by the great majority of consumers who have never experienced them
for themselves, simply because certain big operators within the Industry
are so unprincipled as to continuously and deliberately sell diluted and
debased Aloe products in place of the real thing. The only possible
defence for the Industry – which cannot opt to bring in the Law as it
would like to do, to control some of its own members – is to try to
introduce the necessary voluntary controls for themselves and to either
persuade or shame the less than honest operators into changing their
policy without the help of statutes.
The Problem of
Dilution The oldest trick in the trade in selling any valuable
product in solution is to dilute it with more water. That can sometimes be
true of Scotch Whisky, though there is a limit to which the dilution can
be taken before the consumer begins to notice that something is missing.
In the case of Aloe vera, it seems that the consumer is very insensitive
to noticing the effects of dilution. Lee Ritter, in his book Aloe vera – a
Mission Discovered quotes one Dr R McDaniel as having tested over 200 Aloe
vera beverages in the mid 1980s (presumably in the United States) and
having found that of these only three "contained sufficient Aloe to be of
any medical value to the consumer". He goes on to say that at the time of
writing (1993) according to his own tests "less than one percent of
readily available brands contain acceptable levels of Aloe
vera". It has also become known that one
well–known U.S. brand of Aloe vera effectively contains no Aloe at all. It
has been claimed to be a distillate of Aloe – a claim which seems to
signify that water is turned into steam in the presence of some Aloe
leaves. The steam which comes off is purported to carry with it volatile
constituents of Aloe. The trouble with that is that the product apparently
contains not enough of these to be readily detectable. The question arises
as to how much Aloe is actually used in this boiling off operation – can
it be possible that the same Aloe leaves are used over and over again? The
question is academic anyway, because all the research on Aloe shows that
its active constituents are components of the solid fraction of the plant
and would not be volatile in steam and would not distil over. The product
which gets sold from this operation is the condensate of the steam, and it
has been described as nearly pure water. The present author, upon walking
through the production plant of a U.S. Company which makes genuine Aloe
Extract, noticed the exhaust pipe from an evaporator which was engaged in
converting Aloe Whole Leaf Extract into a concentrate by the removal of
some of the water. The exhaust consisted of a dribble of water into a
drain plus a little vapour. The Production Manager pointed to it and
remarked: "In this factory we put this liquid down the drain – but it is
what some of our competitors sell as product!"
So, to what extent are consumers in the United Kingdom immune from this
type of profoundly misleading practice which has been so commonplace in
the U.S.? Well, it would be really surprising if there were to be any
immunity at all. Most of the Aloe sold in the U.K. comes from the United
States – from Florida, Texas or California. The other principal quantities
come from areas of Mexico or from plantations in Central American States
or the Caribbean, which are very often under the control or influence of
U.S. Companies. U.K. suppliers are for the most part dependent upon U.S.
producers and middlemen. Recently, Aloe Vera Information Service went out
and bought three brands of Aloe on general sale in the U.K. (we have since
tested several more). The analytical findings indicated that one of these
was nearly pure water, a second contained at best 10% or 15% of Aloe with
major adulteration and a third was probably a slightly under-strength Aloe
vera Gel product. The names involved were either respectable or even
prestigious ones in the market place. This did not bode very well for the
interests of British consumers. Dilution – or
even the selling of products as Aloe which may owe nothing at all to
genuine Aloe – still seems to go on in today’s market in the U.K. The
temptation is there in a major way. Genuine Aloe Whole Leaf Extract at a
1:1 strength may, perhaps, command a variety of different prices in the
market. However, quite a common price under the money and market
conditions of 1997 would be, say, £15 or £16 per litre. Naturally, if that
is a typical price for Aloe vera extract at natural strength, it follows
that concentrates of Aloe, if genuine, at from two to several times
natural strength, command correspondingly higher prices at retail level.
The cultivation of the plants, the processing, the transportation across
thousands of miles in liquid form, plus the marketing and distribution
costs dictate that that should be so. Product which has been dried in the
U.S. and sent over in powdered form for re-constituting could easily be
cheaper but would be open to question on grounds of biological activity.
The temptation to sell water, or something close to water, for £15 or more
per litre, is a crude temptation of human greed. The lack of control – and
the real difficulties which exist in organising efficient control – are to
blame for this situation. Another aspect is
that the best quality of Aloe vera is that which has not been put through
either a high level of concentration by evaporation or a drying process,
both of which cause some degradation of biological activity. Many
suppliers sell product which has been highly concentrated and then diluted
again, or products that have been dried and then redissolved. Once again
there is no harm in this so long as the consumer is clearly informed. The
problem is that usually the consumer is not informed. In the UK and
European markets, selling "reconstituted" products, as they are called, is
very widespread indeed, mainly because of the cost savings available on
freight if small volumes or weights of concentrated or dried product are
dispatched across the ocean from the producing country. By contrast the
seller of non-reconstituted products, at single or double strength, pays
heavily for transoceanic freight but delivers the consumer (other things
being equal) a significantly better product. Since there are no labelling
requirements which would distinguish these two quite different situations,
the consumer is once again usually ill-informed about this and companies
therefore compete on very unequal terms with products that may look the
same but which deliver significantly different value for money.
The Detection
of Dilution If the supplier is quite simply adding a major amount
of water to an Aloe vera product, this will become obvious as soon as one
measures the "total solids" of the product. An Aloe vera Gel product
typically contains about 0.46% or 0.6% solids. The reader may be surprised
that the concentration is so low. However, one should remember that Aloe
vera gel is the water-storage organ of the plant. Hence the above figures
are normal values – i.e. they are what one expects Aloe Gel to contain. If
a party were to dilute the Gel ten-fold, this would become 0.05% to 0.06%.
The picture is likely to be complicated by the addition of preservatives.
What would happen in this case is that the preservatives content would
tend to dominate the Aloe content because the latter had fallen to such
low levels. Ultimately one may need to elucidate the preservative content
separately. However, the fact remains that if the solids content of the
whole product is extremely low, much less than the normal content of
solids in Aloe vera Gel, then dilution has certainly occurred. The usual
method of measuring the total solids level is to evaporate a known volume
of the solution to dryness in a vacuum oven and carefully weigh the
residue.
Adulteration with Cheap
Non-Aloe Solids Clearly, the people who sell almost pure water and
pass it off as Aloe are easy to detect and, equally obviously, they are
not afraid of being detected. The circumstances just have not been created
yet to make life sufficiently uncomfortable for them, even though the
Trades Descriptions Act gives the theoretical ability to take
action. Other suppliers who dilute Aloe try to
make out that they are not diluting it, by adding back some solids of a
different kind, i.e. non-Aloe solids. When this is done, simple
measurement of the total solids in the product is no longer capable of
exposing the dilution of the Aloe. Total solids can be made to look
normal, but the point is that the solids are of the wrong kind and will
not possess the biomedical properties of Aloe. This calls for a slightly
more sophisticated form of chemical analysis which is capable of
distinguishing between Aloe solids and non-Aloe solids.
Chemical
Analysis to Detect Adulteration To attempt to distinguish between one
plant extract and another by chemical analysis is not easy without
resorting to degrees of sophistication which make the whole process too
expensive for routine use. This arises from the fact that all plant
extracts from different species have numerous components in common.
However, Aloe can be distinguished from other species to a certain degree
by its special polysaccharide (carbohydrate) component, called
"glucomannan". Tests to distinguish the glucomannan clearly from the other
polysaccharides of other plant species would have to be sophisticated.
However, testing for the presence of polysaccharide per se is not. It is
done by means of a test called the "alcohol precipitable hexose" test. The
plant extract is first mixed in fixed ratio with alcohol (often methanol
is used) and this produces a precipitate (ie. a coming out of solution) of
a material which contains the Aloe carbohydrate. This precipitate can be
separated out and weighed to give a measure of the amount of "methanol
precipitable solids" (MPS) present in the sample. Because these "methanol
precipitable solids" contain the actual polysaccharide component of Aloe,
values of MPS are often quoted by suppliers to give a crude measure of the
biological activity of their product. This "MPS" value is certainly better
than nothing. For example, we can be sure that if a product gave an "MPS"
value of zero, then the product would contain none of the type of
biological activity which is associated with the polysaccharide
fraction. This analytical value is very crude,
however, because some of the organic acids of the Aloe (which have no
biological activity) co-precipitate with the polysaccharides in the "MPS"
fraction and increase its weight without contributing anything
useful. Therefore, a much better measure is to
determine how much carbohydrate is actually in the "MPS" fraction, thereby
excluding these co-precipitating acids. This leads directly to the
"alcohol precipitable hexose" test, in which the "MPS" are first
precipitated and then an analysis is done to find out how much
carbohydrate (as hexose sugar) is present in this "MPS" fraction. This
succeeds in drawing a distinction between polysaccharide in the "MPS" and
the inactive organic acids which are also part of the
"MPS". The "alcohol precipitable hexose" test
is therefore the best routine test we have at present for finding out how
much potentially active polysaccharide is present in an Aloe sample. It is
important to stress "potentially active" because if the Aloe has been
incorrectly handled in processing this polysaccharide, which records
itself as "alcohol precipitable hexose" will lack activity, even though
the analytical result will be unchanged. Also, it is most useful when no
other plant extracts are admixed with the Aloe. Some other plant extracts
(but not all) will bear an "alcohol precipitable hexose" component which
will analyse like Aloe polysaccharide but carry none of Aloe’s biological
activity. The most common substance used for
the adulteration of Aloe is maltodextrin – a cheap carbohydrate material
obtained from corn starch. In the chemical analysis maltodextrin records
largely as "alcohol precipitable hexose", and is potentially very
misleading because it could make it look as if the Aloe sample was
supremely good in respect of its "alcohol precipitable hexose" content
even though, of course, it has absolutely no biomedical activity.
Fortunately, though, the maltodextrin can be detected as an adulterant
because it always raises the result of the "alcohol precipitable hexose"
test to quite abnormally high levels which never would be attained with
real Aloe. Hence the artificiality of the position becomes
exposed. This was the position with the one
U.K. brand of Aloe which we found to have been adulterated. The "alcohol
precipitable hexose" test produced such bizarre high results that the
product could not possibly be Aloe.
Maltodextrin in not the only substance used for adulteration of Aloe
products. Glucose and glycerine have also been used.
The
International Aloe Science Council’s Certification
Programme The International Aloe Science
Council, based in Texas provide Certification of products as being genuine
Aloe. The Council does not only certify products that are close to 100%
Aloe but also products down to 15% (sometimes 10%) Aloe. This means that
certification in itself does not guarantee 95-100% Aloe but one should
view the certification along with the label. Some products include only
15% Aloe with every justification; for example, the other 85% may consist
mostly of fruit juice to make a drink combining the health aspects of Aloe
with an attractive and refreshing flavour. Once again, the key here is
information to the consumer. So long as the consumer is in a position to
know just what he/she is buying, and the description of the product is
correct, whether certified or not, the position is
satisfactory. The key to understanding how
different classes of Aloe product compare is in familiarising oneself with
the different categories of product defined by the International Aloe
Science Council. There are 17 such categories – a number of which may be
highly desirable to permit accuracy of description, but which most
consumers are unlikely to grasp. Aloe vera "Juice" must be 95% Aloe vera
to be correctly described. Aloe vera "Beverage" must contain not les than
50% Aloe vera Juice. Aloe vera "Drink" may contain as little as 10% Aloe
vera Juice for the reasons described above. Aloe vera "Concentrate" must
have had some of the water removed to attain a desired strength, though no
lower limit of such water removal is specified. Obviously it is very
important for the consumer’s sake that these different types of product
are clearly identified on labels.
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