Is black rice milled?

Yes, whole grain black rice is slightly milled (husked/hulled): only the outer, inedible protection layer (hull or husk) is removed while all nutrient-dense parts of the grain kernel (bran, endosperm and germ) are preserved. 

Polished white rice is not a whole grain anymore: further refining fully removes the bran while parts of the endosperm and germ are removed as well. All fiber and the majority of micro-nutrients and phyto-nutrients get lost. 

Why black and purple?
It all comes down to anthocyanin, a powerful antioxidant, anti-inflammatory and plant pigment (type of flavonoid) that colors rice black-purple-reddish, just like it does with blueberries, sweet potato and red cabbage.

More on wikipedia

18 months

Note that we are the ONLY rice producer in the US who puts the ACTUAL anthocyanin level on the box.

This holds us liable  (lab test done for crop year 2018). 

Why does water change color when black rice is soaked, rinsed or cooked?

Anthocyanin is water-solvable. Water mixed with anthocyanin colors black (blueish in case of alkaline water). Simple as that.

Therefore, no one can claim based on this observation merely that a particular rice is naturally or synthetically pigmented. Not ours, not any, let that be clear. A more profound test though is the 'vinegar test'. 

Soaking rice overnight results in up to 15-20% of loss. At home we don't soak our rice and many of our customers don't do either. The longer one soaks, the more the grain become whitish.

How can we figure out whether the rice we got is authentic?

If you want to test pigmented rice for authenticity, do the vinegar test

Anthocyanin acts as a pH indicator. Dissolve black rice in an acid solvent and you get a deep red color. Vinegar is such an acid agent. Mixed with pigmented rice the vinegar should color deep red. This is what you want to see.

Why is black rice brown/yellow/whitish on the inside?

In nature pigment is always located on the outer layers. This is no different for a rice grain. Anthocyanin is stored in the bran, a layer on the outside, whereas the endosperm, at the core of the grain, contains the brown-whitish macro-nutrients (carbs, protein).

Leveling the nursery, prior to seeding. At our friends' black rice farm in Doi Saket (Chiang Mai district). July 2018.



All rice is outlined in an internationally acknowledged classification, based on genus, length-to-width ratio and location.

In this classification, what sets red, black and purple rice apart from brown rice is the presence of high levels of anthocyanin. Among these naturally pigmented varieties, nutrient profiles are (surprisingly) similar and in our view differences, even within a variety, are more likely due to seed quality, farming methods and soil/climate conditions.

Wild rice - and to our surprise we get a lot of questions about this - is a native North American kind of rice and belongs to the genus ZIZANIA, a family of aquatic grasses (more about genus in a moment). 

We are not particularly familiar with wild rice - that's not what we do - but the process to grow and harvest rice is very different. Wild rice grows in shallow waters in a moderate climate and is usually harvested from a perennial, whereas Thai rice plants are short-lived. Soon after harvesting the plant will die. (we are aware of wild rice cultivars being reseeded each year, but again it's not our expertise). To be clear, we don't grow wild rice in Thailand. It's not the eco-system for it. There is one exception, and that's China, in a few regions with a moderate climate wild rice is being grown (but it's not prepared as food).

In appearance, wild rice is taller and thinner, coating is different too. Therefore, cooking instructions aren't the same.


North American region

ie. wild rice

genus ORYZA species SATIVA

most Asian rice

Kernel on the left is Chinese black rice, an example of a JAPONICA subspecies

ORYZA SATIVA JAPONICA are mostly short-mid grain varieties grown in Central Asia. Another famous example is Japanese sticky rice.

Kernel in the middle is the variety we grow, and an example of an INDICA subspecies. 

ORYZA SATIVA INDICA are mostly long grain cultivars grown in South Asia. Well known cultivars are Indian Basmati and Thai Jasmine rice.

Full scientific name for our rice:

Oryza Sativa Indica Sc. khao hom nil.

khao hom nil is Thai and stands for 'fragrant black rice'.

Most Asian rice is domesticated and belongs to the genus ORIZA and species SATIVA. Therefore, ORYZA SATIVA stands for Asian domesticated rice.

This matters in order to export rice from Thailand and to import rice elsewhere. If a variety is not classified, it can't be exported.

Next, for most cases, South Asian rice is long grain (subspecies INDICA).  Length of grains is about 4 times as long as its width. Well known examples are Indian Basmati and Thai Jasmine rice. 

Scientific names for almost any variety in our region start with ORYZA SATIVA INDICA. For our heirlom black rice, add the subspecies name to this  and you get its official name: ORYZA SATIVA INDICA SC. KHAO HOM NIL).

This brings us to the difference with Chinese black rice. These varieties are grown in Central Asia and the subspecies is called JAPONICA, a group of short-mid grain cultivars. So compared to Thai black rice, their appearance is shorter and rounder.

Scientific names for varieties from China, S Korea and Japan usually start with ORYZA SATIVA JAPONICA.  




Gluten is a protein mixture found in rye, wheat and barley. Its elastic properties make dough rise easily. Rice contains no gluten and fits anyone with gluten allergy or sensitivity such as celiac disease.

Glutinous is a synonym for sticky or sweet rice. Starch is made of amylopectin and amylose, two slightly differently linked chains of glucose. Sticky rice is high in amylopectin which makes soaked and steamed glutinous rice sticky.

An example of sticky rice is our Highland Black Glutinous Rice.

Black rice is a whole grain with a glycemic index below 50.

Diabetes is not my medical specialty, I'm a physician with a background in emergency medicine but I try to educate myself further in this direction. in the end, if you are a diabetic, it's your call, you feel what's best for your health.

That said, most black rice varieties (not only long grain) have a glycemic index just below 50 (GI can only be measured in a clinical setting, so this is a test we can not do for each of our varieties separately, but scientific papers about Thai black rice consistently show values under 50 due to high fiber content).

That's a low-moderate GI and therefore, yes, a rather safe choice for someone with a fairly well controlled DM type 2 (monitor your total carbohydrate, intake obviously).

Black rice is a whole grain with high fiber content. That's the kind of carb you want to eat as a diabetic.

Last, be aware that most black rice varieties have similar carb levels (this counts for most macronutrients actually, for micronutrients it's a very different story), but again each one of them comes with lots of fiber.



Rebirth Rice doesn't fumigate with inorganic chemicals (industry standard).

Instead our products are vacuum packed: vastly reducing oxygen level which not only inhibits insect infestation and microorganism growth, but also preserves fragrance and extends shelf life. 

That we don't chemically fumigate is reported on the phytosanitary certificate, issued by the Thai Department of Agriculture (and exchanged with the USDA APHIS in order to enter the US). Contact us anytime to get a copy of the certificate for the batch you got your rice from (mention the date you bought our rice and we track down the according certificate).

To mitigate infestation risk, we are committed to vacuum pack soon after the rice is husked at the mill.

Our rice is vacuum sealed and packed at our own FDA registered workspace in Chiang Mai, Thailand, so we can easily provide the best possible, internal quality control.

Nevertheless, if you would experience any hatched rice, please contact us.​​

How long can black rice be stored?

Any type of pigmented rice which is not packed vacuum, can be stored in dry and cool conditions for around 18 months, whereas vacuum packed pigmented rice easily holds for more than 36 months.

shelf life

18 months

not vacuum packed bag

36 months

vacuum packed bag

Our ‘BEST BEFORE DATE’ (usually on the back panel of our items) is set 12 months after milling/packing and helps determining when the batch you got your rice from was milled, nothing more than that. 

This is sort of our timeline:

We grow rice once a year, while harvesting is done in October/November.

Milling and packing happens about 6 weeks before a batch goes overseas. Crossing the Pacific takes about 3 weeks and then, on arrival in the US, add another 3 weeks before our rice hits the shelves. That makes 3 months. In the US we usually sell out within 4-8 weeks (we ship small batches about 4 to 5 times a year). 

The rice you get is about as fresh as can be!



When is rice growing season?

Rice in Thailand is being grown during the wet Monsoon (basically a regional reversal of trade winds, which brings rain to Northern Thailand from early May to mid-November). Our farmers sow Heirloom Black Rice end of August. Growing cycle is 90 days. 

Do you grow GMO?


We support both heirloom and (unpatented!) traditional open-pollinated rice varieties while only selecting seed saving farmers.

What's your definition of a heirloom?

Some say a variety should be around for at least 50 years, but a first generation hybrid can turn 50, theoretically even a GMO seed could (by time). 

Of utmost importance is if a seed is open pollinated and over generations is able to grow true to type. This is when offspring continually shows the same characteristics as the parent plant. Such a stable seed, in our book, is a heirloom. For this to happen, seeds from the best plants need to be selected and sowed, in case of rice, for up to 10 generations.

We decided to add another condition though and only label a variety heirloom if the seeds have set and saved in a certain ecosystem for at least another 10 years after grown true to type. 

An outstanding example is our Heirloom Highland Black Glutinous Rice, grown and saved as long as rice farming hill tribe families remember. Jasmine Black Rice aka Riceberry on the other hand is true to type since 2011 and has since been grown everywhere in Thailand. So we feel it’s just too early yet to call Riceberry a heirloom. 

How about GMO in Thailand?

GMO crops in Thailand are common: corn, tomato, soy, papaya (and cotton) often are genetically modified.

Nevertheless, we are not aware of genetically modified rice growing in Thailand. The national rice masterplan even outlines a policy which intends to ensure Thailand's reputation as a non-GMO rice exporter.

We'll do an update if we find out otherwise.

How about organic produce in Thailand?

According to the FiBL, Thai organic production has progressed steadily since 1998 with an yearly average growth of almost 40 percent.  Still, less than 1% of agricultural land in Thailand is managed organically. 

Soil degradation due to conventional farming is a big hurdle to overcome: good fertile soil can take up to 3 years to build up and during the first two transition years yields can implode and as livelihood depends on agriculture, some farmers simply cannot carry this financial burden. Luckily, grassroots and academic support is rapidly growing. We know of collaborative incentives by the government and local temples to provide organic compost and fertiliser.

Meanwhile, there is a (small) movement of young Thai from Bangkok and Chiang Mai who move to the countryside and start a small organic farm.



Which heavy metals do you analyse?


Before we proceed, I'd like to mention Low heavy metals Verified, an encouraging, non-commercial initiative that has laid a self-certifying framework for food producers (due to the absence of any regulation by the FDA and the USDA). In line with the standards they have set, we reach the highest level, A+++, for all 4 heavy metals.   

How about Arsenic contamination?

That said, let's focus on Arsenic (As), a natural component in the earth's crust, which is present everywhere around us. We all breathe, drink and eat arsenic in small amounts, safely.

Arsenic presents in two forms, either ORGANIC or INORGANIC and it's the latter that is a known carcinogen (with cancerous effects). Unfortunately, the situation in the US is that Arsenic in groundwater sometimes reaches critical levels. Whereas US legislation fo Arsenic levels in drinking water is enforced, for food standards there are only guidelines available from the EU and the WHO.

In 2013 the US FDA concluded, after analysing 1300 rice and rice-based food samples on total and inorganic arsenic, that the amounts of detectable inorganic arsenic were low enough to not cause any adverse health effects.  

Nevertheless, Arsenic values are one of Rebirth Rice's main criteria to select rice growers and farmer cooperatives and we reassess our findings every two years.

We screen on TOTAL Arsenic (organic + inorganic) and if values exceed 0.25 mg/kg, INORGANIC Arsenic will be quantified. This reference point is based on:

  • Statistically Northern Thailand shows an organic-to-inorganic Arsenic ratio of 3:1. This implies that, for a value of 0.30mg/kg of TOTAL Arsenic, INORGANIC Arsenic levels can be expected to be around 0.10mg/kg.

  • Early 2016, the Eu set the maximum levels of INORGANIC Arsenic to 0.25mg/kg for husked brown and other pigmented rice varieties.

  • Also in 2016, the US FDA proposed a Maximum Contaminant Level (MCL) of 100ppb (0.10mg/kg) for INORGANIC arsenic in infant rice cereal. This is a tripled down value, compared to adults, as young children consume approximately three times more food on a bodyweight basis. Rebirth Rice has no intention to make processed rice products, certainly not infant rice cereal, but we have decided to set this value as a standard for our husked rice.

Rebirth Rice Co., Ltd.
113/14 Moo 10
Suthep Muaeng
Chiang Mai 50200
Rebirth Rice LLC
1425 Broadway STE 20334
Seattle WA 98122