Japanese cake/pastry with self-heating packet inside plastic wrapper?!
The clear plastic wrapper has a smaller white packet affixed to the inside, and once I open the outer wrapper, this white packet immediately begins heating itself.
It doesn't get too hot, just a few degrees above body temperature, I'd say.
Does anyone know what this is, what activates it, and what its purpose might be?
The writing on the wrapper is all Japanese except for the words "Seiyo Kyujitsu" and "Hakata Torimon."
Answers: I'm in possession of Japanese mini cakes/pastries that are filled with some kind of seed/bean paste.
The clear plastic wrapper has a smaller white packet affixed to the inside, and once I open the outer wrapper, this white packet immediately begins heating itself.
It doesn't get too hot, just a few degrees above body temperature, I'd say.
Does anyone know what this is, what activates it, and what its purpose might be?
The writing on the wrapper is all Japanese except for the words "Seiyo Kyujitsu" and "Hakata Torimon."
i wouldn't doubt the fact that they are trying to achieve the illusion of slightly warm cake that just came out of the oven, which many people like.
the packet might be for that purpose.
air-activated heat packets contain powered iron, some water, salt and maybe activated carbon. the powered iron gets reduced by the oxygen into iron oxide (rust) when exposed to air. the process generates heat. to speed up the process, salt acts as a catalyst, and the activated carbon (stuff you find in yoru brita water filter) distributes the heat evenly. all non toxic ingredients.
a lot of companies sell air activated heat packets, thermacare, heatmax.
"HOW DO THEY WORK?
Hokkairo are small pouches containing iron, water, cellulose, vermiculite, activated carbon and salt. Opening the plastic wrapping exposes the slightly moist iron to the Oxygen in the air, forming Iron Oxide (FE2O3, commonly referred to as 'rust'). 'Rusting' isn't the fastest chemical reaction on the planet (one which would normally take days, or even weeks), so salt is added into the mix to act as a catalyst, and thus, considerably speeding up the reaction. Now that the reaction is giving off heat, the carbon is used to evenly distribute the heat around the packet and the vermiculite (an inert mineral with insulating properties) is used to retain the heat, thus giving off a gentle warmth. Cellulose is added as a filler, to give the pouch a bit of 'volume'. "
http://www.alientimes.org/Main/PersonalH...
now you are probably asking how the packets don't get activated before they open the package. well, many food manufacturers in the world use nitrogen (an inert gas, the air we breath in on a day to day basis normally contains 78% nitrogen) to seal up boxes of food, cookies, crackers, potato chips, etc. the inert gas helps food staying fresh. the company that made that japanese snake cake thought it was a good opportunity to use technology already on the market to slip in a heat pack, and to make sure it doesn't get activated by adding in some nitrogen gas.
consider the fact that your japanese snack cake is a marvel of modern technology.
1) machine that makes the filling and another to make the cake, both gets combined and flash baked.
2) they get packaged, the packaging contains an inert gas to keep the food fresh, and a heat packet inserted so when you open the package, the cake warms up and you are able to eat warm cake.
I believe you are talking about 博多通りもん - Hakata Torimon. http://www.meigetsudo.co.jp/products/tor...
accordinf to the frequent ask quection on the link provide the by company who made the product http://www.meigetsudo.co.jp/faq.html
明月堂のお菓子には膨張剤?添加物は使用しておりますが、保存料は一切使用 致しておりません。
弊社のお菓子の袋の中は真空パックになっておりまして、 脱酸素剤が 一つ一つに入っております
it translate to "In order to keep freashness, We use vacum packaging, and put the free-oxygen absorber in each pack along with inflating agent additive."
So once you open pressure in the bag got release and the inflating agent go to work.
You can also check out how they make it.
http://www.meigetsudo.co.jp/products/tor...