In the modern age, the comparison of the qualities of rehydrated, dehydrated foodstuffs with those of fresh fruit and vegetables seems an obvious analogy to draw between fresh and dried herbs. In nutrition, therefore, the answer to the matter is one of unanimous verdict of both lay and scientific opinion – fresh is always better than dried!

Yet, because the origins of the (eventually Royal) Pharmaceutical Society lay in the development of the science of analysis of the exotic dried herbs that came to London by land and sea at the height of the British Empire, so still the texts are copied from generation to generation, slavishly and unquestioningly continuing to labour it’s out of date and illogical conclusions.

Perhaps we should not be surprised to know that the origins of the pharmaceutical industry lie in the belief that dried herbs are more useful than fresh herbs because of the 19th century idea that they must be ‘more chemically concentrated’.

That is how we have all been conditioned throughout the last hundred or so years. Yet, it is the case that although plants do contain’ active’ chemicals, plant physiologists have realised for more than a quarter of a century that most plants potentiate their biological activity by high organised and extraordinarily complex ecological adaptations. It is hardly a great leap of imagination to see that these extraordinarily complex ecological adaptations are, generally, exactly what it is that sets whole plants apart from chemical components in their use in medicine. (For more detail, see the scientific paper at this link: Plants, tinctures and colloids).

These systems appear to depend largely on complexes of plant proteins, sugars and lipids, that in turn are dependent on water for their structural integrity. Although drying herbs allows them to be kept in a dry state for long periods of time (as is required for the purposes of commerce), this method of preservation depends upon the process of ‘denaturing’, or destroying, the very subtle web of physical phyto-chemical structures that evolution has created over countless millennia in order to enhance biological activity. Life was not designed to protect dead tissues – biological life is the ultimate system of competitive self-preservation!

According to the 19th century textbooks, plain percolation was invented at a time when concentration of chemicals was all the rage and simply in order to cut costs and increase the manufacturer’s margins. Traditionally percolation is a rapid and cheap extraction process that takes the herb to the point called “exhaustion”. It is noteworthy that the British Pharmacopoeia require that (a) percolation is anyway preceded by (strong) maceration and (b) must be followed by concentration by boiling!

Modern herbal science would not normally approve of boiling because of the damage done to most of the herbal complexes, described in the paragraphs above.

At Rutland, we have discovered that often up to half of the dissolved solids in herbal medicines may consist of amphiphilic molecules, such as glycolipoproteins. These play an essential role in the biochemistry of extracts but are damaged by boiling. For all these reasons, therefore, we do not support methods dependent purely on percolation.

Instead we use an adaption of the traditional practice of daily shaking, that we call our ‘rolling barrel method’. Macerated barrel are simply rolled through 180° every day for a period of many weeks to ensure even mixing as the active micro-structures are released.

Plants are natural products and, being natural products, are extremely flexible in how they work. There are no hard and fast rules about how to arrive at a correct strength for extraction and therefore this area can be a bit daunting to investigate. Usually there is no absolutely ‘correct’ extract but a range of flexible options. We have always tried to work with natural flexibility wherever we can. Although a few people tend to find this puzzling, our very wide range of extracts has been developed over the years together with some of the nation’s most experienced herbalists. There are many different factors to take account of when selecting extraction parameters. Other reasons of individual preference include preferring differing alcohol strengths, for reasons varying from those given by the 19th century physio-medicalists, to modern technical reasons such as preferential solubility coefficients of perceived active complexes.

More often, it is what the practitioner is used to using – and that can vary from practice to practice and from school to school. Many parallel traditions have evolved over the years, from the ‘official’ Pharmacopoeia to other strengths popularised by various teachers. Many strengths evolved with manufacturers who sought a way of maximising profit because certain strengths do not require nearly as much labour to make as others. We believe it is wrong for the manufacturer to dictate the strengths the herbalist should use but prefer to try to accommodate professional herbalists’ experience.