Preface: What Is in the Plant, and What Is Left in the Jar?

A stem of Dendrobium officinale grown on a rock face in the Yandang Mountains, a ginger rhizome dug from the uplands of Bentong in Pahang, and a cranberry raked from a flooded bog in Wisconsin have little in common except this: each is sold for what is inside it, and what is inside it changes with where it grew, how it was dried and how it was stored. The buyer cannot see any of that. What the buyer sees is a label, a price and, if the seller is careful, a certificate of analysis.

This book is about the distance between the plant and the jar. It asks four questions. Why does the same species make different amounts of its characteristic molecules in different places? What exactly are those molecules in three crops: the acetylated glucomannan of Dendrobium officinale, the gingerols and shogaols of ginger, and the A-type proanthocyanidins of cranberry? What happens to them when the plant is dried with hot air or freeze-dried under vacuum? And how can a buyer, a processor or a regulator know, batch by batch, what is actually in the product? It reads these questions beside the Chinese materia medica, which recorded two thousand years ago that “drying in shade or in sun, the season of harvest, … and the land where it grows, each has its rule”.

What this book is and is not

This is a book of plant chemistry and food engineering. Each chapter states an established piece of chemistry, physics or statistics and runs it in a short Python program so that the reader can change the numbers and see what happens. Unless a source is given, the numbers in the programs are illustrative; they show how an argument works, not measurements of any farm, factory or batch. Where the book proposes how a model applies to a crop, it says so in a hypothesis box, with the result that would show it to be wrong.

Note

This book is not medical advice. It does not claim that any plant, food or extract treats, cures or prevents any disease in people. Where it reports clinical research, as on cranberry and urinary tract infections in Chapter 4, it reports what the studies and systematic reviews found, including where they found no benefit, so that readers can see the state of the evidence; it is not a recommendation to use any product. Anyone with symptoms of illness should see a doctor. Anyone who is pregnant or breastfeeding, takes prescription medicines (for example blood thinners such as warfarin), or has a long-term illness should ask a doctor or pharmacist before taking any herb or extract in amounts larger than those found in ordinary food. Rules on what a label may say about health differ from country to country; nothing in this book is a claim for any product.

How to read the boxes

As in the other books of the 5D Library, different kinds of statement are kept apart.

Evidence

Evidence boxes report published findings, with their sources.

Calculation

Calculation boxes give formulas and short Python programs. Every program runs as printed with a standard Python 3 installation and nothing else, and its output is shown underneath it.

Hypothesis · not established

Hypothesis boxes hold the author’s ideas. They are labelled “not established”, and they say what result would show them to be wrong.

Source text

Source text boxes quote the classical texts, with the author’s translation.

Note

Note boxes give cautions and explain choices.

The plan of the book

Terroir as biochemistry. Why altitude, the day–night temperature swing and the growing medium change what a plant accumulates: the Arrhenius equation, respiration losses at night, and a daily carbon balance.
Dendrobium officinale: glucomannan and its acetyl groups. The structure of the main polysaccharide, the mannose-to-glucose ratio, and the Chinese Pharmacopoeia’s assays, with a Beer–Lambert standard curve fitted in Python.
Ginger: from 6-gingerol to 6-shogaol. The reversible dehydration that heat drives, its rate constants and activation energies, and what it does to pungency.
Cranberry: A-type proanthocyanidins. What the A-type link is, how the BL-DMAC assay measures these molecules and why the choice of standard matters, and a careful separation of laboratory anti-adhesion findings from clinical evidence.
The heat and mass transfer of freeze-drying. The triple point of water, the Clausius–Clapeyron equation, a moving sublimation front, and why freeze-drying spares heat-sensitive molecules.
Batch variation and the certificate of analysis. Sampling statistics, chromatographic fingerprints, contaminants, and water activity as a limit on microbial growth.
The classical materia medica. The Shennong Bencao Jing and Li Shizhen’s Bencao Gangmu on place of origin, harvest and drying, read beside modern chemistry.
Practice and a pre-registered experiment. A four-step check for buying plant raw materials, a triangle test for blind tasting, and a pre-registered experiment comparing freeze-drying with hot-air drying of Bentong ginger.

This edition

This is version 1.0.0, the first complete edition: a preface and eight chapters, in Chinese and English. Corrections, and references the author has missed, are welcome through the 5D Library website.

Disclosure

The author and his group operate four websites on agricultural products and freeze-drying technology, dendrobiumofficinale.com, bentonggingers.com, cranberrysupplier.com and freezedriedexpert.com, and have commercial partnerships with the Dendrobium officinale growing area of Dajing town, Yueqing, Zhejiang, China, and with food-processing supply chains in Malaysia. The author therefore has a direct commercial interest in the crops and processes discussed in this book. The book does not promote any batch or product and gives no prices. Every model, all the Python code and every test method are published openly for anyone to check.

Fan, Y. (2026). Molecules and Terroir: Polysaccharides of Dendrobium officinale, Gingerols of Zingiber officinale, A-Type Proanthocyanidins and the Mass Transfer of Freeze-Drying [本草的分子与风土] (Version 1.0.0). 5D Library. https://doi.org/10.5281/zenodo.23693057 · Licensed under Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0).