Once in a while we succumb to deep frying our food. Deep frying doesn’t do much good for our health but our taste-buds crave for that crispy crunch on the outside and moistness of the food on the inside. All cultures I know have some deep fried dishes. Some families use a deep fryer whilst others use the wok or a saucepan for deep frying. Whichever type of utensil is used for deep frying, filtering the oil is a necessity. Only simple tools are required to filter the oil. The packet of filter shown above can be found at wet markets, Daiso and in the sundry section of most supermarkets.
An inevitable question – do we throw away the oil after deep frying? If not, how many times can we re-use the oil? Much to my surprise, the oil can be re-used quite a large of number of times!
The Food Lab advises on the factors that affect the freshness of oil. Listed below are the most pertinent ones :-
(a) the type of batter that covers the food. Basic rule of thumb: the more particulate matter you introduce to oil and the finer those particles, the faster your oil will break down. Example, oil used for battered fish will remain fresh longer than oil used to deep fry crumbed fish (even if you skim the oil regularly).
(b) The type of oil and the temperature at which it is heated for deep frying. Generally, refined oils like most peanut, canola, vegetable, and corn can be heated to higher temperatures than raw oils like extra-virgin olive oil or most sesame oil.
(c) the type of food being deep fried. Example, vegetables fried bare tend to dry the cleanest, imparting very little to the oil. On the other hand, fatty meats like chicken wings or bacon will render fat as they cook. This fat can then mix with your fryer oil, causing it to break down a little faster.
Photo above shows a saucepan of oil (set aside for about 30 mins after deep frying to cool down) being filtered. The dark colour of oil comes from deep frying ikan bilis.
Filtering is an important step to maintain the freshness of the oil for another 2 to 3 uses. Notice the fine particles left behind in the oil. These fine particles cannot be removed by skimming the hot oil with a mesh strainer during the process of deep frying.