Traditional idli, dosa batter is typically made with parboiled rice + urad dal. Even in recipes that ask for raw rice, parboiled rice is still added in small quantities. Why is that?
What happens if one makes idli, dosa batter with just raw rice?
To find out, I ran an experiment and here are the results:
The Experiment:
Make 2 batters -> 1 made with urad dal + parboiled rice, the other with urad dal + raw rice.
Observe the differences in the resultant batter, idli and dosa made from these 2 types.
Step 1: Soak
The previous night, I soaked two 1/2 cups of urad dal separately. I also soaked 1.5 cups of raw rice in 1 container and 1.5 cups parboiled rice in 1 container.
Basically I used a 1:3 ratio of urad dal: rice.
Please Note: Parboiled rice is colloquially referred as ‘boiled’ rice, even the uncooked version. You will find the term boiled in the pictures to indicate parboiled.

Step 2: Grind the batter
Here’s how I made the batter:
- Drained the rice and dals separately
- Ground the 2 Urad dal portions separately with 1/2 cup water in a blender (exact same power settings, time)
- Ground the rice varieties separately with 1 cup water in a blender ( exact same power settings, time)
- Mixed the corresponding dal and rice batters

One difference I noticed was that the texture of the ground parboiled water was a little coarser than the raw rice batter which was smooth.
Despite grinding them for the exact same amount of time, notice in the picture below – how the raw rice batter is nice and smooth.

Now notice how the boiled rice batter texture looks…The texture felt gritty (in tamil we say that the batter is ‘kora-kora’, which means sand-like texture between the fingers)

This is obviously due to the effect of the par-boiling process, which causes the starch in the rice to retrograde and harden when compared to the soft, starch-y texture of raw rice.
Step 3: Ferment the batter
It was a warm, sunny day that day. So, I placed the batter in the patio and left it to ferment during the day.

In the evening (about 10 hours later), I bought the batter inside, full of excitement, to see the state of the batters. I opened the lids to find this:

The par boiled rice batter was well fermented, and bubbly. The raw rice batter was not showing much signs of fermentation, unfortunately.
How fermented was the parboiled rice batter? Well fermented indeed…
(Please note, the yellow tinge below is from taking the photo in the night due to poor lighting)

So, anyway, I thought “Oh well, I guess it is kind of hard to ferment raw rice…”. I left the raw rice batter out overnight and went to sleep.
To my surprise, the next day morning I woke up to find the raw rice batter fermented – Oooh-lala!!!

So, it is possible to ferment raw rice batters, it just takes more time. Remember par boiled, as the name suggests, has been par cooked. That 1 extra step gives the lactobacillus bacteria the boost it needs to access to the sugars in the rice quickly.
You may notice recipes with raw rice batter asking you to throw in some poha, puffed rice or a handful of cooked rice while grinding – exact same reason. This gives the bacteria a headstart in digesting and fermenting the grain.
Ok, moving on, next step….
Step 4: Making the idlis
Using the same size ladle, I measured out the exact same amount of batter and steamed the 2 types of batter side by side.
Here’s how they turned out:

While the above photo may not accurately reflect the difference, I used my grill to show the difference in the cross section below.
See, how the parboiled rice is wider. This is because the batter had more rise, aka more lift compared to the raw rice batter.

One more observation: The parboiled rice batter came off much more easily from the idli plate compared to the raw rice batter which was a bit sticky.

Finally taste test: I did not find a big difference in taste between the 2 idli types, unlike in the dosa (see below).
The parboiled version definitely had bigger and well aerated idlis compared to the raw rice version, which made it easier to scoop it out, dunk it in chutney, generally feel good about the resultant idli, etc.
My tip: If you are a beginner, sticking to par boiled rice will make you more confident with the idli making process.
Step 5: Making Dosas
I used the batters to make dosas. Here’s what I found:
Parboiled rice Dosa: Notice the lightness/airiness of the batter, which makes it easy to peel the dosa away from the tava once it is done.

Next up, Raw Rice batter:
The raw rice batter sticks to the tava more. This gives it a better browning, making it tastier and crispier than the parboiled rice batter.

Here are the 2 dosas side by side:

If you don’t have a well oiled or smooth tava, then using raw rice might end up sticking to the pan, become messy and creating more problems than the boiled rice batter (which lifts off easily from the tava).
However, the raw rice dosa was definitely tastier (had those wonderful crispy, jagged edges) than the parboiled rice batter dosa.
Conclusions
Here are the conclusions from my study:
- Batter
Parboiled rice batter ferments quickly and more easily compared to raw rice batters - Idli
Idli rises better, has more spring and is poofier, when made with parboiled rice compared to raw rice
Idli made with parboiled rice comes off the idli plate cleaner than raw rice batter - Dosa
Dosa made with raw rice batter sticks to tava more creating a crispier and tastier dosa when compared to dosa made with boiled rice batter.
Hope this post was useful to you all in understanding the differences in properties between raw rice and parboiled rice.
All my idli dosa aficionado’s out there, what do you think? What has been your experience with working with raw rice or boiled rice batters?
Do post your thoughts and comments below!!
Can you help me to find out best paraboiled rice in CA-USA? Main purpose for diabetic .
Can we say that IDLI & other south Indian dishes made from paraboiled rice are good for diabeties.
Hi Chetan, from my GI post:
“Parboiling automatically does not mean lower GI. It depends on the type of grain that is being parboiled and the level of parboiling. But, typically, having the parboiled version seems to be nutritionally superior and lower in GI compared to the raw form.
For eg, in 1 study, they found that the GI of a certain type of long grain white rice was 83, but the parboiled version drops the GI to 67.”
Link here:
https://www.upgrademyfood.com/which-rice-is-best-for-a-diabetic-glycemic-index-analysis-part-1/
Re: which is best parboiled rice brand in USA, I am not sure.
Swetha – I am not used to having any sticking of the idli when removing them from the pans, so I was surprised to see that you did. But I make sure to grease the pans with a solid fat (usually but not always ghee). Also letting the Idli cool to below 130°F/65°C before trying to remove them from the pan is another process step that helps them release cleanly.
I have not made idli in a while and you have now challenged me to run the experiment with raw rice. Please tell me what type of raw rice you used. I am asking to see if there might have been a significant difference in amylopectin to amylose ratio which I know makes a big difference.
Hi Doc,
Haha…I predicted 100% that I will get commented on the sticking of the idli plates, even wanted to add the disclaimer that – “hey yes, grease your idli plates or add cloth, rest your idli, etc to avoid this problem but when you don’t, notice that raw rice batter is stickier than parboiled rice” :).”
Re: raw rice, I used Laxmi brand ponni raw rice. Thanks for posting your thoughts, always appreciate it!!
Swetha
Happy to see that I can live up to your expectations😉
😁
Very nice article!! Beautifully done!
What do you think about rice seviya. Aapam. Idiyappam.. raw rice vs parboiled rice?
Hi Sindhu, thank you! I haven’t written yet about Raw vs parboiled, but I have written about idli rice Vs boiled rice here:
https://www.upgrademyfood.com/idli-rice-vs-boiled-rice/
dear Swetha,
How kind of you to do this thorough research on this proverbial raw rice vs. parboiled rice dilemma. Due to your arduous experiment , you saved me the trouble of doing it myself. I will continue to use idli rice (aka. parboield rice) for my idlis. They are still not perfected but almost there. Very very kind of you to post such useful info…….really appreciate it
Thank you so much!! Your comment made my day!! 😃
Hi Swetha,
Quite impressed with your experiments. We(few) somtimes just “want to get it done with ” and lack detailing . When i say WE i mean not all but a few. Since your ratio is 1(urad dal) : 3(parboiled) especially for dosas, wondering if the ratio can be altered to 1:4 , i.e 1(urad dal) : 3(parboiled) :1 (raw rice). Wonder what the combo will give output as.. will definately try it out. Another thing to point out is the brown crispy edges and the dosai itself requires a bit of more caramalisaton( if my word is correct) of the broken sugars from the raw materials itself, what will it take to add more of something(yet to decide) that will make it brown enough. This is from commercial aspect as well as presentation wise. Do comment . Thanks,
Venkat
Google “maillard reaction” then follow the many trails that emanate from that bit of bait. It has many pieces but is not the only way to achieve browning. You can get there with caramelization which is different and also with charring. The chemistry is somewhat different in each, and each has its place in the kitchen.