I have a commercial grade built in deep fryer that I put in my outdoor kitchen. I have been using it for awhile now and I just leave the oil in the fryer and put a stainless steel cover on it. The oil looks to be in good shape not dark or anything and the food taste good. The oil doesn’t smell or anything like that. I will use the fryer once a week and change the oil every 2-3 months. Is this a safe and healthy way of storing the oil? Draining the oil after every use is not ideal as there is a lot of it. Would like anyone’s input if possible. Thanks
Assuming that your fryer is protected from the elements, the safety issues for an outdoor fryer are the same as for an indoor one. Fryer oil can be used over and over again. It absolutely does not need to be to be changed every use. Restaurants that use fryers a lot will filter the oil on a daily or near daily basis, but even oil that gets used a lot doesn't get changed daily. Changing the oil is not a matter of safety. While there is some minor long-term health risk associated with eating oil that is past its peak quality, it's not an immediate food safety issue. Since you use your fryer only about once a week, it should be fine for three months perhaps filtering it two or three times. Even the filtering is for quality purposes only, pathogens cannot survive in fryer oil.
The bottom line is that oil that still tastes good is fine to use.