The Story of Extraction
The main difference between cold-pressed and refined oils lies in how they are made. Cold-pressed oils are extracted by mechanically crushing seeds or nuts at low temperatures, a method traditionally known as 'kachi ghani'. This process is slow and yields
less oil, but it keeps the natural flavour, colour, and nutrients of the source ingredient intact. Refined oils, on the other hand, undergo a multi-step industrial process. This often involves using chemical solvents like hexane to extract maximum oil, followed by high-heat treatments, bleaching, and deodorising. These steps create a neutral-tasting oil with a longer shelf life and lighter colour, but they also strip away many of the natural vitamins and antioxidants.
Nutrients and Flavour
Because of its gentle extraction process, cold-pressed oil is a nutritional powerhouse, retaining antioxidants, Vitamin E, and healthy fatty acids that are otherwise lost during refining. This also means it carries the distinct aroma and taste of its source—think of the sharp punch of mustard oil or the nutty notes of groundnut oil. This makes it ideal for dishes where the oil's flavour is a key component, such as in traditional Bengali or South Indian cuisine. Refined oils are neutral in taste and aroma, which allows the flavour of spices and other ingredients to dominate. They are essentially blank canvases, which can be useful in certain recipes, but they provide fewer nutritional benefits.
The Smoke Point Debate
Smoke point—the temperature at which an oil starts to burn and break down—is a crucial factor in Indian cooking. It's a common belief that cold-pressed oils have low smoke points and are unsuitable for frying. This isn't entirely true. While the refining process does increase the smoke point by removing impurities, many traditional cold-pressed oils are perfectly suitable for high-heat cooking. For instance, cold-pressed mustard oil has a high smoke point of around 250°C, making it excellent for frying. Cold-pressed groundnut and sesame oils also have smoke points high enough for most daily cooking tasks like sautéing and tempering. The smoke point of cold-pressed groundnut oil, for example, is around 160°C, while most home frying happens between 160°C and 180°C.
A Guide for the Indian Kitchen
So, which oil should you use? The answer is: it depends on the dish. Think of your oils as tools, each with a specific job. For Deep Frying (Samosas, Pakoras, Pooris): While some cold-pressed oils like mustard can handle it, refined oils with their higher smoke points and neutral flavour are often preferred for deep frying, ensuring a crispy texture without imparting a strong taste. Refined groundnut oil is a popular choice for this. For Tadka (Tempering): This is where cold-pressed oils truly shine. The quick, high-heat burst of a tadka is perfect for blooming spices in flavourful oils. Cold-pressed mustard oil is a classic in North and East India, while coconut and sesame oils are staples in the South. For Everyday Sabzis and Dals: For your daily sautéing and gravy preparations, cold-pressed oils like groundnut, sesame, or mustard are excellent choices. They add a layer of authentic, traditional flavour to the dish. For Drizzling and Dressings: For any raw application, like chutneys or salads, always choose cold-pressed oils to get the maximum flavour and nutritional benefits.
