For fruit and vegetable chips vacuum frying, most of them will be finished in 30~60 minutes.
The moisture will be removed quickly from
solid state to gas state in the reduced pressure. How can we make sure it will
be successful? Expect using high effective vacuum pumps to supply stable and
high vacuum degree in short time and the evaporation temperature will become
much lower, we should also ensure oil temperature could raise rapidly in short
time and keep stable in long time. Especially when we put the materials into the
frying chamber, the oil temperature will drop quickly, to make the oil temperature
raising rapidly is the most important key for the whole frying process.
Use steam as heating source, the most important
cause is we can heat the oil uniformly with heat exchanger, to make sure every
chip fried in same temperature and the final product quality is consistent, increase
the final product pass rate and production capacity; the second cause is it will
heat fast and release more heat than other heating source, like hot water and
oil, especially in the reduced pressure condition; the third cause is we can
control and adjust the frying temperature easily, reach the set temperature
quickly and accurately; the another cause is it’s safe and clean. In industrial
food production process, using fire is not a brilliant choice, there are too
much potential risk. For fire heating, there are many other disadvantages: the heating space is small and the heat
exchange effect is not good; the oil temperature is uneven; control difficultly……
then the result must be frying time prolonged, too much moisture in the oil, the
worst thing is the final product quality is bad.
Some people always explain that we don’t
want invest so much money in the machines. But, they ignore one important fact,
more advanced machines will help them save more energy cost and increase
product price. Keep overall viewpoint on one thing, you will discover which is the
best way.