A Map of Paozhi (炮制): Aromatic Material Processing in Traditional Chinese Blended Incense

From sorting and soaking to steaming, simmering, roasting, and drying

Paozhi (炮制) is the preparation and processing of aromatic materials before they are blended into traditional Chinese incense. Depending on the material, it may involve sorting, washing, soaking, steaming, simmering, roasting, or drying. Its purpose is to prepare the material, reduce unwanted raw qualities, and shape how it behaves in the finished incense.

When natural aromatic materials arrive at the workshop, can they simply be ground into powder, blended together, and made into incense?

More than twenty years ago, when I first began learning Chinese blended incense, that was exactly what I did. I did not understand material processing at the time. I bought the ingredients, ground them, blended them, formed the incense, and burned it.

The result was almost unbearable. The incense carried strong raw and unpleasant off-notes.

Only after I began reading old incense texts and asking experienced makers did I understand that, in traditional Chinese blended incense, there is often an important stage before the materials are actually blended:

processing — paozhi (炮制).

Even today, I still come across incense makers who grind purchased agarwood, sandalwood, gansong, and other aromatic materials directly into powder and use them without further processing.

The incense can certainly still be made this way. But the raw character, unwanted odors, and other qualities of the untreated materials may remain in the finished incense and strongly affect how it smells when burned.

Processing itself is not mysterious. Sometimes it simply means removing stems, dirt, or unwanted parts.

Sometimes the material is soaked.

Sometimes it is steamed or simmered. Sometimes it is roasted, treated with liquid ingredients, or gently dried with heat.

Tea, wine, honey water, rice-washing water, and other liquids may also be used during the process.

In simple terms, paozhi does three things:

• It prepares the material for use.
• It removes or reduces qualities that are not wanted in the finished incense.
• Through water, heat, and processing media, it changes the state in which the material eventually enters the incense.

Old Chinese incense texts preserve many such methods.

The map below covers some of the more common and easier-to-understand approaches. It is not a complete catalogue of traditional aromatic processing. Different texts, materials, regions, and makers contain many more specialized methods.

The purpose here is simply to establish a clear basic map.

1. A Basic Map of Paozhi Methods

For modern readers, common methods can roughly be organized into four groups:

This is a modern way of organizing the techniques for easier understanding. Old incense books generally do not begin with a chart like this. Instead, they describe the treatment of one material at a time.

The first volume of Chen Shi Xiang Pu (陈氏香谱), for example, contains a section on the preparation of aromatic materials and records methods for du'nou, frankincense, borneol, sandalwood, agarwood, patchouli, maoxiang, jiaxiang, and many others.

And in practice, processing often involves more than one action.

A material may move through a sequence such as:

• cut → soaked → dried with heat
• soaked → treated with another liquid → slowly roasted dry

So “processing” is often better understood as a sequence of treatments, rather than one isolated technique.

2. Preparation: Getting the Material Ready

Preparation is the most basic stage. Natural aromatic materials do not necessarily arrive in a condition that is ready for incense making.

They may contain stems, soil, weeds, damaged parts, or other unwanted material. They may also be too moist, too large, or otherwise unsuitable for the next step.

Common actions include:

sorting, trimming, scraping, cutting, filing, rubbing, sieving, and drying. These may sound simple, but even here the maker is already making decisions about scent.

When discussing patchouli, gansong, and linglingxiang, Chen Shi Xiang Pu gives very specific instructions:

“Remove the stems, stalks, and weeds; dry thoroughly; rub apart and winnow away the dust. Do not wash or scald them with water, as this damages the fragrance.”

That detail is important.

Today, we often assume that washing something more thoroughly must be better. But aromatic materials are not ordinary raw ingredients.

If a cleaning method also removes the aroma you want to preserve, then it is not the right method.

So preparation is not simply about making a material “clean.”

It is also about deciding:

What should be removed?

And what must be preserved?

3. Liquid-Based Processing

Here, “liquid-based processing” simply refers to methods in which a liquid is used as the main medium.

Besides water, traditional incense texts also mention:

tea, wine, honey water, rice-washing water, and other liquids.

Common actions include:

washing, soaking, steeping, and moistening. Liquids can soften a hard material, change its moisture level, carry away certain unwanted qualities, or allow a processing medium to enter the material before the next stage.

Sandalwood: A Liquid-Processing Example

In Chen Shi Xiang Pu, several different liquids appear in methods for treating sandalwood:

• wine
• tea
• water with white honey
• honey mixed with wine

One method says:

“Split the sandalwood into small pieces and soak it overnight in clear tea made from lacha.”

But the process does not end there.

After soaking, the sandalwood is dried with heat before moving on to further treatment.

This shows an important feature of traditional processing:

Soaking is often only one stage in a longer sequence.

Moistening

The idea of “moistening” is especially easy to understand through the treatment of maoxiang.

Chen Shi Xiang Pu says:

“Select good maoxiang, file it into pieces, moisten it overnight with wine and honey water, then roast until yellow and dry.”

That short instruction already contains three stages:

preparation → moistening → roasting

This kind of sequence is very typical of traditional aromatic processing.

4. Heat-Based Processing: The Hard Part Is Knowing When to Stop

Heat-based processing uses temperature to change the material.

In this article, we will focus on three common and relatively clear methods:

roasting, roasting after treatment with liquid media, and gentle heat-drying. They all use heat, but they do not work in exactly the same way.

Roasting

Roasting is the easiest to picture.

The prepared material is heated while its condition is constantly observed. But the difficult part is not simply knowing how to roast.

It is knowing:

When should you stop?

For sandalwood, Chen Shi Xiang Pu instructs the maker to file it into pieces about the size of grains of rice, then heat it slowly:

“Roast over a gentle fire until the smoke turns purple; stop as soon as the raw odor is gone.”

The important words are:

stop as soon as it is gone.

Longer is not automatically better.

If the treatment is insufficient, the unwanted raw character remains. If it goes too far, qualities that should have been preserved may also be lost.

A great deal of real processing knowledge lies in this kind of judgment:

Has the color changed enough?

Is the moisture right?

Has the smell changed?

Is it time to stop the heat?

Roasting with Processing Media

Some heat treatments happen only after the material has already been soaked or treated with another liquid.

One sandalwood method in Chen Shi Xiang Pu is especially detailed:

First, split the sandalwood into small pieces.

Soak it overnight in tea.

Dry it with gentle heat.

Mix it with honey and wine.

Let it soak again overnight.

Then:

“Dry it slowly over a gentle fire.”

Taken as a whole, the sequence is:

cut → tea soak → heat-dry → honey-and-wine treatment → soak again → slow heat-dry

This makes one thing very clear:

Traditional processing is not simply a matter of “heating the raw material.”

A piece of sandalwood may already have passed through several transformations before it ever reaches the actual blending stage.

Gentle Heat-Drying

Gentle heat-drying is often used after a material has been treated with tea, water, wine, honey water, or another liquid. The purpose is to bring the moisture back under control so the material can continue to the next stage.

Old texts therefore often describe sequences such as:

soak → dry with heat

or:

simmer → dry with heat

and then continue with another process.

In the sandalwood method above, for example:

tea soak → heat-dry → honey-and-wine treatment → soak again → final heat-drying

Another sandalwood method recorded in Chen Shi Xiang Pu combines finely filed sandalwood with water and white honey, simmers the mixture, and then dries the material again with heat.

So gentle heat-drying often acts as a bridge between different stages of processing.

5. Combined Moisture and Heat: Steaming and Simmering

Some methods cannot be understood purely as “water processing” or purely as “heat processing.”

The clearest examples are:

steaming and simmering.

Both rely on moisture and heat together.

Steaming

Steaming uses moist heat to change the condition of a material. Sometimes it changes texture or physical state. In some cases, it can even help separate different parts of the material.

Chen Shi Xiang Pu gives a very visual example involving du'nou incense material.

When black and white portions are mixed together, the material is placed in a vessel and steamed over a rice steamer.

After steaming:

“The white rises to the surface, and the black sinks below.”

The two portions can then be separated.

This is a useful reminder that processing is not always simply about “making something smell better.”

Sometimes the first problem is physical:

How do we prepare the material itself for use?

Simmering

Simmering is also common in old aromatic processing. The liquid may be plain water, or it may contain wine, honey, or another processing medium.

One agarwood method in Chen Shi Xiang Pu instructs the maker to:

file the agarwood finely,

place it in a silk bag,

suspend the bag inside the vessel so that it does not touch the bottom,

cover it with honey water,

and simmer it slowly.

Even with a word as simple as “simmer,” there are many technical decisions involved:

How finely should the material be cut?

Should it sit directly in the liquid?

What liquid should be used?

Should the material touch the bottom of the vessel?

How strong should the heat be?

How long should the process continue?

All of these details are part of processing.

6. Tea, Wine, and Honey Are Also Processing Tools

One distinctive feature of traditional Chinese aromatic processing is the frequent use of different liquid media.

Besides water, old texts regularly mention:

tea

wine

honey or honey water

rice-washing water

and other liquids.

It is important to distinguish these from the main aromatic ingredients in a finished formula. When tea appears in the processing of sandalwood, for example, that does not necessarily mean tea leaves are being added as a major aromatic ingredient in the final incense.

Tea is functioning first as a processing medium.

Sandalwood

Traditional records include methods using:

tea,

wine,

honey mixed with wine,

and water with white honey.

Maoxiang

It may be moistened overnight with wine and honey water before being roasted until yellow and dry.

Agarwood

Old texts also record a method of slow simmering in honey water.

A processing method can therefore involve several variables:

What material is being treated?

How is it cut or prepared first?

What liquid or processing medium is used?

How long is it soaked or moistened?

How is it heated afterward?

And at what point does the maker stop?

Together, these decisions form the actual process.

7. Paozhi Is Usually a Sequence, Not a Single Action

If we remember only words such as “roast,” “steam,” “simmer,” and “soak,” it is easy to imagine traditional processing as a collection of isolated techniques.

The old texts show something more complicated.

Sandalwood alone makes this very clear.

Within the short sandalwood section of Chen Shi Xiang Pu, we can find several different approaches.

One method is:

file into rice-sized pieces → slow roast until the raw odor disappears

Another is:

slice → simmer in wine → lightly roast

Another is:

slice → soak in tea → heat-dry → treat with honey and wine → soak again → slowly heat-dry

And another is:

file finely → simmer with water and white honey → heat-dry

All of these begin with:

sandalwood.

But they do not produce sandalwood in exactly the same processed state.

That is perhaps the simplest way to understand paozhi:

The name of the raw material is only the beginning. Before it actually enters the incense-making process, it may still have a long way to go.

8. Quick Reference: Common Paozhi Methods

This table is only a basic map of common methods, not a complete list of traditional aromatic-processing techniques. Old incense texts contain many more specialized operations, and individual aromatic materials may have their own distinct treatment paths.

Those are better explored one material at a time.

Conclusion: What the Material Is — and What It Has Been Through

More than twenty years ago, the first time I made incense directly from untreated aromatic materials, the strong raw and unpleasant smell was what first made me realize that the material itself was only the beginning.

The more old texts I read, the more makers I asked, and the more incense I made, the clearer this became:

In traditional Chinese blended incense, a great deal of the work happens before the actual blending begins. Gansong and patchouli may need to be carefully sorted and cleaned without washing away their fragrance.

Maoxiang may be moistened with wine and honey water before being roasted. Sandalwood may be soaked in tea, simmered in wine, roasted, heat-dried, or treated with honey and wine.

Agarwood also appears in traditional records with methods such as slow simmering in honey water.

These steps may never appear on an ingredient list, but their effects remain in the finished scent. This is one reason an ingredient list cannot fully predict how Chinese blended incense will smell.

Even today, I still encounter incense makers who skip much of this work and simply grind natural aromatic materials directly into the blend.

It is certainly simpler.

But the raw and unwanted character of the material may remain as well.

So when we encounter a Chinese blended incense and read:

• agarwood
• sandalwood
• gansong

we still know only part of the story.

What the material is matters.

What the material has been through matters just as much. That is the basic idea behind aromatic material processing in traditional Chinese blended incense.

Continue Exploring Chinese Incense Craft

• How Jun–Chen–Zuo–Shi organizes ingredients after processing
• Why handmade Chinese incense rests after it is made

Source

Chen Shi Xiang Pu (陈氏香谱), Volume 1, section on the preparation of aromatic materials.