• # Let us discuss the Capacity of Pressure Cookers here

Members,
In AE section, I raised a question regarding the Capacity of Pressure Cookers to feed rice for 50 personnel. I received two unconvincing answers. They have said that a 22-litres capacity Pressure cooker would be sufficient to cook rice for 50 personnel. I don't agree with their responses. Since I could not counter their responses there, I have raised the issue here, to get it solved.

Since we all use Pressure Cookers, Let us discuss it seriously. My study reveals that One Kilogram of rice cooked can be eaten by six (6) average people satisfactorily. To feed 50 people, we need to cook 8 KGs of rice. Can a 22-litres capacity Pressure cooker cook 8 Kilograms of rice in one go?

What is the quantity of rice that can be cooked in the following Pressure Cookers of different capacities? Please indicate the quantity of rice against the capacity.

3 litres ..................
5 litres...................
7 litres...................
10 litres...................
20 litres.................
22 litres.................
.
• Pressure and volume are inversely proportional when temperature is constant. I guess we can apply that here. The more the pressure increases faster the rice gets cooked.
So the smaller volumes cook faster. But since your quantity is higher you should pick bigger volume. Density of rice is 1452 kg/m^3. Volume of rice is 8/1452= 0.005m^3. The is five litres. So rice occupies 23% of that 22 litres cooker. And my dad says 8 kg rice can take up to 2 litres of water. So 7 liters is occupied in 22 litres. It is plenty enough to cook rice then I guess.

The stronger a light shines the darker are the shadows around it.

It is good to see your good working on volumes, density and pressure. Yet I think it is not possible to cook for 50 personnel using a 22 litres capacity pressure cooker. It would be better to have it seen practically.

If you have a pressure cooker(any brand or model)at your home, Just try to cook one Kilo of rice in it. Then come out with the result.

First, Let us try and use a 5 litres capacity cooker and find out as to how much rice can be cooked in it, and how many people can be fed..

No life without Sun

• A pressure cooker cannot be filled up fully to the brim. Only 2/3 portion of the cooker can be filled. Thus, a 5-litre capacity cooker can be filled only up to 3.25 litres. To cook one Kg rice, it would need approx 2 litres of water. So, a 5-litre capacity cooker can cook only 1 or 1.25 kg of rice. One Kg rice can be easily distributed to 6-8 adults satisfactorily.

If a 5-litre cooker can feed 6 or 8 adults, a 20/22-litre cooker can feed only 24-32 people only.

Do you agree or disagree?

No life without Sun

• If you take 1 cup = 240 ml and 1 quart = 4 cups or 960 ml or almost 1 litre; 1 cup rice + 2 or 2 1/2 cups water makes about 3 cups cooked rice so a 2-litre cooker would hold about 6–7 cups cooked rice This will be sufficient to about 4 people. Proportionately you take a 22-litre capacity cooker can give you food sufficient to 40 people roughly. It may not be sufficient for 50 people.
We have a 5L capacity pressure cooker. we cook in this and it will be sufficient for about 10 people. If you take this proportion also a 22 L pressure cooker may be sufficient to about a maximum of 40 people.
This is purely a rough calculation. But my wife says with her experience of using 5L p[ressure cooker a 22L cooker will be sufficient to about 35 to 40 persons only.

drrao
always confident

• When it comes to number of persons then the rule of proportionality does not truly applies. The reason is in a large number of sample there is statistical variation and as all the people will not take good quantities of rice it will be proportional but the trend will be converging rather then diverging or proportional.

For example if a 10 ltr cooker can make rice for 20 people then a 20 ltr will be able to feed more than 40 people may be 45 to 50. With the same logic a 30 ltr will be able to meet the demand of more than 60 people.

I will try to explain it slightly in a different way. Take a cookery text book for graduate students. We will find there recipes where the ingredients for 5 persons as well for100 persons are given. I have seen, as I have interest in cookery and my recipes are published in many places including ISC, that the ingredients for 100 persons are not 20 times as that of for 5 persons. They are considerably lower.

Hope this explains the things.

Thoughts exchanged is knowledge gained.

• Neeru,
I differ. When I say rice meal for 50 people means, it is a good amount of rice consumption by adults. On an average, a guy will be able to consume 150 grams of cooked rice in a south Indian marriage feast. Thus, One Kilogram of rice is sufficient only for 6 people.

Today, I took out a brand new 3-litre prestige pressure cooker and showed to my wife, and asked who all can eat the rice cooked in this cooker? My wife's simple response was " Just you and I" leaving little for others..

If a 3-litre cooker can provide cooked rice only for 3 adults, I am sure, a 22- litre cooker can provide rice only for 22 - 25 personnel.

No life without Sun

• If we are assuming that 50 persons rice requirement will be 50 times multiplied by one persons full diet then I am afraid we will have to go for a bigger size cooker in the range 25 to 30 ltr.

I still believe that a cooker in the range of 20 to 25 will be sufficient for this purpose. In absense of any standard chart by cooker manufacturing companies regarding your query we have to make a best possible assessment.

Whenever there is food to be taken then there are many side dishes also and due to that the rice requirement will not be the theoretical 50 x 1 persons diet.

While preparing any dish we take this in account and decide the quantity accordingly.

Thoughts exchanged is knowledge gained.

• The rice meal I am talking about is a standard meal with all the varieties of curries, dal, side dishes etc. A meal will have a minimum of 150 grams of rice alone for an adult. In the south, there are courses like rice with dal, rice with sambhar, rice with Vathakolambu, rice with rasam, rice with puliseri, rice with butter milk/curd.
No life without Sun