What is important is that you get the oil to it's max temp before cooking anything in it. Peanut oil doesn't break down at high temperatures and is ideal for frying both fish and chips. https://www.funfoodfrolic.com/puri-recipe-how-to-make-perfect-puri-poori While butter may not be the best oil for deep frying, ghee is a very solid option. So how can you figure this out? These oils are best for sautéing When frying or roasting food you should choose an oil with a high smoke point, above 375°F. They float on the oil while frying because the hot oil makes them puff up and fill with air. How healthful an oil is for frying depends on when it breaks down and how long a person heats it for. Often “refined” is something you avoid in food but the best oil for frying is always refined. Ghee is pure butterfat, which means that the dairy proteins and sugars (lactose) have been removed. Less refined oils, like extra virgin olive oil and extra virgin coconut oil, have a shorter shelf life and a lower smoke point, and they're full of flavor. This gives ghee a higher resistance to burning than butter, and it’s heat stable at higher temperatures. For frying, you need an oil that has a high smoke point. Some of the more healthful oils include olive oil, avocado oil, and canola oil. The best oil for frying will resist oxidation and and rancidification at high levels of heat. The key is the relative degree of saturation of the fatty acids contained in the oil . Otherwise fat absorption into the food is much higher resulting in a more soggy and unhealthy result. It differs a great deal on the quality of the oil. Refined. Puris are small, round, flat pieces of bread made of unleavened wheat flour. Although all of the oils on our list do have this, do not assume all oils in that category will.