Top positive review
Stanley 0.5 Litre Classic Food Jar, Black
on 20 July 2014
Virtually indestructible! Or at least very hardwearing and able to withstand a lot of abuse. However, that is not how I treat my Stanley vacuum products. I currently own a 1L, 1.9L vacuum flask and now a 0.5L vacuum food jar. This is my first vacuum food jar by any manufacturer so I was particularly interested in how it performed to keep food hot or cold. In all probability I will only use it to keep hot food hot. I have already used it to keep porridge and soup hot, although not together, of course.
The trick to keeping food, or for that matter liquids, hot or cold is to preheat or pre-cool the vacuum container (flask/food jar). This can be achieved by first filling it with hot water or with ice water or ice cubes and to leave standing for a short while. The reason for this is that the vacuum container, inside and out, is made from stainless steel which needs to be heated or chilled prior to the foodstuff being inserted. If there is much of a temperature difference between the metal lining and the foodstuff, heat will flow from the hotter material to the cooler material. For example, placing hot soup in a vacuum flask or food jar at ambient temperature will reduce the temperature of the soup slightly so that it does not remain hot for as long as expected. Alternatively, placing ice cream in a vacuum jar at ambient temperature will raise the temperature of the ice cream which may begin to melt. It too, will not remain cold for as long as expected. First time users often fail to appreciate this.
If these simple rules are obeyed there is no reason why a steel vacuum flask or food jar should not keep its contents at a respectable temperature hot/cold for between 12 - 18 hours. I have made coffee at 8.00am which I have taken to work and brought home and drunk the remainder at 9.00pm the same day. Correct preparation is paramount otherwise the performance of these all-steel vacuum containers may disappoint. For shear ruggedness I give the Stanley Food Jar top marks.