Research Update: Pine Nut Species and Varieties

Thesis progress

I am currently 90% through with the data analysis and 20% through with writing this nutty thesis. Firstly, a big thanks to you all for your valuable contributions to this website and research! I’m fighting really tight deadlines now but as the messy picture has started to clear up, I shall begin a gradual process of sharing some discussions and my struggles with the last bit of data analysis (hopefully someone out there can help me out). My final colloquium is scheduled exactly 1 month from now. As appreciation for your interest and contributions to this research, I would like to extend an invitation to the first five persons who is interested in attending my final presentation here in Wageningen University, The Netherlands to send an email to and I will make the arrangements for my special guests. 🙂

Pine Nut Species and Varieties

Several weeks ago, I had received a very good comment from Dr Charles Rhora of Rhora’s Nut Farm & Nursery regarding the variety of P. armandii that their farm is cultivating. I had been intending to make a post regarding this but time constraints and procrastination have delayed it till now.

Dr Rhora had expressed that P. armandii grown on the farm produces good edible seeds and indeed, it is true that there are more than one variety of P. armandii  (up to 5 official varieties according to botanical literature (Eckenwalder, J.E. (2009). Conifers of the World; The complete reference, 1st Ed. Timber Press, Inc: Portland Oregon.). It seems that only one thick-shelled variety originating from the region of Shaanxi and Shanxi of China are causing the bitterness (INC, 2011). The thin-shelled varieties (such as the one grown by Dr Rhora, according to information on his website) do not cause bitterness, however, at the moment, distinguishing species is difficult enough, let alone the variants of it, hence it has been recommended by the Chinese authorities that P. armandii be avoided altogether to simplify matters. The report that furnished this information was published by the International Nut and Fruit Council. I have included an excerpt below, the full report can be accessed [HERE].


To continue the discussion about varieties, further readings into botanical literature have revealed that subdivisions of botanical species are controversial and often disputed and necessitate DNA-based investigations for more comprehensive classifications of species and their varieties. Single species can exist in hundreds of variants, of which only a few may be officially recognized. A couple of different analytical groups have already informed me of their efforts to develop their DNA-profiling methods and I look forward to hearing more from them in the coming months.

Meanwhile, we will have to rely on industry information and visual identifications. There has been a recent press release also by the International Nut and Fruit Council. You can download the pdf document of the press release from HERE*. For your convenience, I will summarize the main points from the document: *I was informed that the link to download the document does not work and I can’t get it to work either, so you could access it by googling for “INC press release pine nuts” and it will be the #7 hit!

1) Chinese Chamber of Commerce and Chinese Tree Nuts Association are about to release  at the end of May, a handbook with pictures and descriptions detailing the species of pine nuts exported from China.

2) They have issued a statement that P. armandii (regardless of variety) should be avoided.

3) The Chinese, English and Botanical names of the various species have been listed in the document, I’ve copied the table here:

Source: Press release by INC

As you can see from above, there is quite a selection of Chinese pine nuts on the market and a good many of them are nicely edible, unfortunately this incident with the bitter-causing P. armandii variant has tainted the reputation of Chinese pine nuts.

Identification of Pine Nut Species

For the second part of my thesis, I have documented the identification of pine nuts on the market using a variety of information sources including (1) commercial information (2) pictures on trade sites (3) reference samples collected from authorities and suppliers (4) botanical descriptions (5) fatty acid profiles and (6) seed counts and physical characteristics. Still, I am ‘bombed’ with new information every now and then regarding the species on the market, posing new difficulties in the identifications. I’m hoping that the handbook to be released at the end of May by the Chinese authorities will shed some light on this issue.

For now, here is a clear picture of the 8 reference species that I have collected and identified for this research. See the differences? The key of identifications is below:

A = P. armandii / Armand pine / Hua shan song 华山松 |K = P. koraiensis / Korean pine / Chinese Red Pine / hong song 红松 | S = P. sibirica / Siberian stone pine / Siberian Cedar / xiboliya hongsong 西伯利亚红松 | P = P. pinea / Mediterranean stone pine | G = P. gerardiana / Chilghoza pine | M = P. massoniana / Masson’s pine / ma wei song 马尾松 | U1 = P. yunnanensis according to industrial sources and trade sites but does not match botanical information nor fatty acid profile and remains to be determined (HELP!!) | U2 = P. pumila according to the provider of the sample but again there are no other sources to back this up (HELP AGAIN??).

Even though my thesis will be submitted and defended before the release of the new handbook, I will try my best to get my hands on it and share the information with you.

Wow what a lengthy post! Alright it’s back to thesis writing 🙂 Hoping to share again soon!


About grrrrracey

I love to eat, I love to cook, and I love to dig into every mystery about food!
This entry was posted in Announcements, Research Updates, The Great Pine Nut Mystery. Bookmark the permalink.

3 Responses to Research Update: Pine Nut Species and Varieties

  1. Nicole M. says:

    So this literally just happened to me. I made the connection, googled it, found your thesis and identified the offending armandii variant – far too rounded, far too dull in sheen. Everything tastes horrible now. At least it’s temporary. But seeing as the prevalence of this is under-noticed and underreported, I would like to know if you have any recommendations of who to report such a thing to. FDA? Poison control? One would wonder. Congrats on your thesis, either way – it looks like you did a damn thorough job!

  2. I have noticed we stopped eating & enjoying pine nuts about 5 years ago. Prior to this we usually enjoyed the triangular shaped species. Then I saw a shift in the species we could buy – to smaller, more oily, oval-shaped nut. Once we only were able to buy this kind we have barely touched them.

  3. baumgrenze says:

    Hello Grace,

    Thank you for the explanation. Is there some way we can get the FDA in the USA to develop a test for these ‘toxic nuts’ and to block their importation into the USA. China seems comfortable testing tor traces of GMO corn and/or rice from the USA and blocking them from the Chinese populace.

    I found it ‘interesting’ that the Chinese Chamber of Commerce strongly recommended that no P. Armandii pine nuts be exported to the EU!

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s