Technically, how different is a rice cooker from a slow cooker (aka crock pot)?
I have a rice cooker but I use my slow cooker[1] a lot more. It's especially awesome for cooking steel cut oatmeal. Start it the night before and wake up to oatmeal with all sorts of fruit in it.
I personally think a slow cooker is more useful–and they're not really more expensive. But maybe they're just the same.
- Rice cooker: Cooks until water evaporates/absorbs, then warms
- Crock pot: Cooks at a steady temperature, usually for items immersed in a liquid (for water, that's generally around boiling temperature), without evaporating the liquid. In general, more convenient to keep the liquid at a fixed temperature.
- Crock pot (Expensive ones): Can set specific temperature (instead of just boiling or low/high)
Evaporation:
- Crock pot: Tends to minimize it, for long periods of cooking items in liquid
- Rice cooker: Minimizing evaporation not a concern/engineering-constraint
Insulation (insulation of heat in total; not about ergonomics):
- Crock pot: Generally better insulation/less-heat-loss, as it is used for long periods of cooking
- Rice cooker: Insulation a much lesser concern as expected period of use is smaller
- Insulation affects energy consumption
Pot material:
- Crock pot: offers a variety of pot material
- Rice cooker: generally metal (sometimes with coating)
- Affects what leeches into the food
- Insulation characteristics can be better or worse (energy consumption)
- Cleaning costs (weight, handling, sticking)
- Heat distribution across the food (fine detail that isn't relevant to someone who asks this)
- Retention of flavours/substances on pot surface and in pot (probably fine detail as well)
- Reactions with food (fine detail)
Cost:
- About the same cost for the same size and quality (similar components: thermostat + feedback circuit + heating element + pot + insulation)
- Rice cookers are a bit simpler because it has only 1 temperature setting (something set a bit above boiling point of water) => simpler = cheaper
- Rice cookers are simpler because they do not need to minimize evaporation => simpler = cheaper
- Rice cookers are simpler because they have lower priorities on insulation => simpler = cheaper
If you cook soup/stew overnight with a rice cooker, you'll need to start with a lot of excess water, and end up with much higher electricity bills.
Rice cooker, some veggies and/or meat, water, lots of spice, wait 30min and you have a huge pot of soup piping hot ready to eat. Not just hot, but all the veggies or meat is thoroughly tender like it 'was' cooked in a crock pot. Only thing is it ended up taking some 30 min rather than a lot longer.
To me a rice cooker cooks almost like a moderate pressure cooker.
Rice cookers generally give you no control over the temperature. They cook at one temperature for awhile, until the food temperature raises above the boiling point of water (meaning the starches in rice have absorbed it all) then they click into warming mode. With a crock pot you have temperature options and it will stay at that temp until you tell it not to (or a pre-programmed cycle does).
I have a rice cooker but I use my slow cooker[1] a lot more. It's especially awesome for cooking steel cut oatmeal. Start it the night before and wake up to oatmeal with all sorts of fruit in it.
I personally think a slow cooker is more useful–and they're not really more expensive. But maybe they're just the same.