Design milk cartons which have a litmus strip that changes color depending on the freshness of the milk. A face could be printed over the strip - turning green when the milk is spoiled.
The idea that i have just read is great!!!
Why? It's simply because it easily detect spoiled meat to prevent such health damage especially on the part of your children..
I suggest you add more spoiled detector for the benefit of everybody..
thats a very good idea many of this have i drunk from the carton in the morning only to get lumps of milk between my teeth. becaue in the morning you don't look at date on the carton.
this is a really good idea, but if people don't look at the date on the carton of milk, what makes you think that they are going to look at a small piece of ltimus paper at the bottom of the carton?
Spoiled milk is a surprisingly diverse topic. There are countries (like the US me thinks) where the milk seems to be sitting with a stop watch, and precisely at midnight after the date has passed - zapp! - the milk turns chunky. Over here on the European continent, the date is more a general guideline, and often the milk stays fresh several days longer (before it turns... sour, not chunky). For that, the face would be very useful because the date isn't very reliable.
Good idea-provided you can convince the milk producers to go for it.I've found that if I choose the smaller milk cartons (1/2 Litre) the milk seems to stay fresher longer.I have feeling/theory why this might be so.Once a Litre carton of milk is opened, air(containing bacteria ) can get in.By the time the carton is half empty-the empty half will contain a lot of bacteria(compared to the half-full 1/2 litre carton) So my suggestion is buy the 1/2 Litre cartons!
midoh wrote:;-D Good idea-provided you can convince the milk producers to go for it.I've found that if I choose the smaller milk cartons (1/2 Litre) the milk seems to stay fresher longer.I have feeling/theory why this might be so.Once a Litre carton of milk is opened, air(containing bacteria ) can get in.By the time the carton is half empty-the empty half will contain a lot of bacteria(compared to the half-full 1/2 litre carton) So my suggestion is buy the 1/2 Litre cartons!
Very cool theory - you could easily test it by shrinking the carton (e.g. with a rubber band) to see if the milk stays fresh longer.
By the way, while American cartons can be closed again, in many European countries you tear the carton open and there's always a little hole left. No idea if it makes any difference, just an observation.
A green face to indicate spoilt milk-sounds fine. But how about
a message which is visible only when the milk is spoilt
like when the milk is fresh strip is blank; when its spoilt
a message "milk spoilt oh oh" apperas in red color may be.
yair3777338's original posting about using a litmus strip is probably the best idea. Sour milk is acidic. It will turn blue litmus red. There are more sensitive strips, which may give advance notice of what is going on. A pinch of baking soda added before the milk goes 'off' fully restores the pH to alkaline and prevents the souring of milk. Aarthi's idea can be incorporated by printing the message in blue litmus on a blue paper, which will appear red on the milk going sour.
Ultimately someone will add to the milk encapsulated 'Smart Soda' , which will release the alkali as needed to keep milk fresh for much longer.
Why not write the message "milk spoilt oh oh" in normal blue print ink on blue litmus strip. When milk is fresh; message is not visible but when milk spoils blue; litmus turns red revealing the apparently
hidden message.
My reluctance for printing in litmus, it being
a vegetable dye what is its compatibility to being used as a printing
medium?
In all this one point not seriously looked at is that whatever the sensing mechanism it has to be in continuous contact with the milk. The sensor should not leach anything toxic into the milk and it has to be stable in continuous contact with an essentially water based medium. SInce it goes on a commodity like milk it should be low cost..
I very much appreciate this idea. If its anything I simply cannot stand, it's gulping a mouthfull of sour milk in the mourning, even smelling it, turns my stomach. It really ruins my day
by showmethegadget on Tue Jan 28, 2003 10:16 am 
There are countries (like the US me thinks) where the milk seems to be sitting with a stop watch, and precisely at midnight after the date has passed - zapp! - the milk turns chunky. Over here on the European continent, the date is more a general guideline, and often the milk stays fresh several days longer (before it turns... sour, not chunky). For that, the face would be very useful because the date isn't very reliable.
