Idli Dosa FAQs | How to make perfect Idlis and Dosas

Idlis and Dosas are traditional south indian dishes. Its requires some patience and time to make them. When we make them at home, we all want them to come out great. But sometimes we don't manage to get fluffy, soft idlis or crisp dosas.

In this post I will explain the basics of the method for making idlis and dosas including the fermentation do's and don'ts. I will also explain how you can make the best idlis or dosas at home.
Basic method for making the idli-dosa batter:

For making the idlis in the traditional method, urad lentils and rice are soaked for a time period. The ratio of urad dal to rice is 1:2. This is not the thumb rule. You can try this ratio and if things do not turn well, you could use 1:1 ratio or 1:3 ratio of urad dal and rice respectively.

After the rice and urad lentils are soaked well, they are ground and mixed together and left to ferment overnight for a period of 9-10 hours. This makes up the basic batter for south indian dishes like idlis, dosas, uthappams.

We all like the idlis to be soft. In fact, much softness of the idlis depends on the quality of the rice and urad dal/black lentils and the fermentation process:


Rice:

For the idli batter, traditionally parboiled rice is used. Parboiled rice is pre-processed rice. Hence it reduces the time required to pre-soak before grinding by an average of 3-4 hours. Parboiled rice also has gelatinized starch which gives an added texture.

The softness of the idlis depend on a certain starch-Amylopectin found in it. To make softer idlis, you will need over 80% Amylopectin.

How can you find out about the percentage amylopectin content in rice? There is one rule, you can follow, though:
Generally, there are two types of starch in rice:- Amylose and Amylopectin Long grain rice has 22 % Amylose and 78 % Amylopectin, Medium to short grain rice has 18 % Amylose and 82 % Amylopectin.
So its better to use short to medium grain sized rice. If you don't have access to parboiled rice, you may use a good quality rice.Please do not use rice flour as it gives a poor texture. You can use cream of rice also known as rice rava or rice sooji. Cream of rice is coarsely ground rice. But the problem with cream of rice is that the manufacturers do not mention or disclose the type of rice grain used to make cream of rice. So the percentage of Amylopectin might not be acceptable. You may have to experiment from brand to brand.
Urad Dal or Black Lentils:

I have seen people using skinned, spilt urad dal. I myself using these. But you can use whole urad with the black skin. The only problem will be that the black fragments of the skin will be seen in the batter once the dal is ground. You also won't get white colour in the idlis.

Skinned or decorticated whole urad lentil is better to use. If you are using spilt and skinned urad dal, then add fenugreek seeds.

There is a problem with the split urad and that is - when the the pulse is split mechanically a lot of heat is generated and this process destroys much of the wild yeast. Thus you have to add fenugreek seeds to help in the fermentation process.

You can use Urad Dal flour. The only problem you have is that some of the wild yeast is destroyed by heat during the milling process. So you will need to add fenugreek seeds.

Fenugreek Seeds

Fenugreek seeds draw the same type of wild yeast as the Urad Dal. So, using fenugreek seeds just adds more yeast to the batter.


How and What causes the fermentation of the Idli - Dosa Batter

The fermentation in the idli-dosa batter is caused due to the presence of an air-borne wild yeast, which is drawn by the Urad dal and Fenugreek seeds from air. The batter has to be kept for 9-10 hours for fermentation. To know exactly what is fermentation, read this link: What is Fermentation

Some Do's and Dont's to aid in the fermentation process:
Do not over-wash urad dal or the fenugreek seeds, as it washes away the collected wild yeast.Chlorinated water and iodized table salt are not friends of this wild yeast.
The Chlorine in the water can destroy the wild yeast. Use spring water, boiled or filtered tap water to avoid Chlorine.In our homes we use common table salt which is iodized. The iodine can destroy the wild yeast. So, you can use non-iodized salt.Homes which are centrally air-conditioned with hypo-allergenic filters, reduce the supply of this wild yeast. Avoid adding retarding agents before you keep the batter overnight for fermentation. The fermentation can be retarded by ingredients like curd-yoghurt, baking yeast, baking soda or baking powder. Only after fermentation is complete , you can add curd or the baking powder or soda as required or needed.Temperature for fermentation:

The best temperature for fermentation is 86º F to 90º F. If the temperature is below 86º F, it will take longer to achieve an acceptable level of fermentation. If the temperature is higher than 90º F, the batter becomes sour. Acceptable level of fermentation is when the batter has reached 250% in volume (Two and a half times the original volume).

In cold countries or in cold season, its difficult for the batter to ferment. You can do the following methods:
Preheat the oven for a few minutes. Then close it and keep the batter inside the oven.You could also keep the oven light on. Keep the batter inside the oven. The heat and warmth of the light emitted from the oven will help in the fermentation process of the batter.If you don't have an oven, you could keep the batter in a warm place or warm corner in your kitchen. Type of bowl or utensil to ferment the batter:

You will need to use a good large bowl as the batter doubles up and rises after fermentation.
In the olden days, earthen (Terracotta) wares about 5" deep and 16" diameter were used.
We do not have such bowls or pans now. One can use stainless steel bowl, glass bowl or plastic bowl having a large diameter. A 12" diameter bowl will have more than twice the surface area of a 8" bowl to catch the wild yeast. If you don't have large diameter bowl, then divide the mixture in to two separate bowls.

Two 8" pans will be same as one 12" pan. The depth of the pan should be such that it can hold 4 times the original amount of Rice & Urad Dal.

Making Idlis and Dosas of the fermented batter:

After the batter is kept overnight for 9-10 hours and if everything goes well, the batter doubles up and now you can make the idlis or dosas. There is no need to stir the batter as air bubbles are trapped in the batter. Mixing them will release the air bubbles. Just gently mix the batter if you have to mix it. These air bubbles while cooking help in making the idlis fluffy and soft.

Some people add some curd or baking soda or baking powder to the batter before making the idlis. But this not really required. If your batter has fermented really well, you don't need to add any baking ingredients.

Now for making the idlis, you can steam the idlis in the idli moulds. You get these metal idli containers which are used to make idlis. To know about making idlis in the microwave oven, read
this post: How to make Idlis in the microwave oven

You can also use this batter for making dosas. If you like thick and soft dosas, you could use this batter as it is. To make thin dosas, you could add a little water to the batter. You can even use this batter for making uthappam. To know the difference between idli batter and dosa batter, you can read this link: Difference between Idli Batter and Dosa Batter

If there is left over batter, then you can refrigerate it. Don't keep it outside as the fermenation process continues and over fermantation makes the batter sour and may even spoil it. Use the refrigerated batter in next day. Avoid keeping it for more than 1 day.

I hope you this post really helps you and you manage to cook really soft idlis and crisp dosas at home :-)