In recent times, each one of us is becoming more conscious of our diet, closely monitoring the details of the food we consume. People are now more aware of the different components of food, thanks to the wide range of information available, particularly on the internet.
One topic that is currently being discussed is the difference between hot-pressed and cold-pressed oils. But what exactly do these terms mean?
Pressed oil refers to oil from which easily solidified substances have been removed through pressing and cooling. The main difference between refined oil and pressed oil lies in the extraction process. Cold-pressed oil is extracted naturally without compromising its nutritional value, while refined oil undergoes a filtration process involving heat and chemicals, resulting in a loss of nutritional value.
To gain a clearer understanding of cold-pressed and hot-pressed oils, let’s explore some basic information about them.
History of Pressed Oils
The history of pressed oil can be traced back to the Indus Valley Civilization. Archaeologists discovered oil-pressing machines and charred sesame seeds while excavating the ruins of Harappa, which were estimated to be around 5000 years old.
Terms such as “kolhu” and “ghani” were used in ancient times to describe the process of cold-pressing oil. “Ghani” refers to a long cylindrical instrument made of wood or stone, resembling a mortar and pestle, which was used to crush oilseeds. This simple method of oil extraction did not require heat.
Oil Extraction Processes
To better understand the differences between pressed oils and refined oils, it is essential to examine their production processes and inherent characteristics. Here are the key points:
Hot Pressed Oil
- Hot pressed oil is mechanically produced using metallic extraction machines, typically made of iron.
- The seeds are crushed at very high temperatures ranging from 200°C to 250°C.
- The mechanical parts used in the extraction process are generally made of iron, which may pose potential health risks.
- Hot pressed oil requires less manpower as expellers, screw conveyors, and other parts of the system are employed.
- The quantity of oil obtained from hot pressing is higher compared to cold-pressed oil.
- The nutritional value of hot-pressed oil is lower due to the heat involved in the extraction process.
- The aroma of hot-pressed oil is not as prominent.
- The acidic value of the oil is high, necessitating the need for further refining.
Cold Pressed Oil
- Cold pressed oil is also produced mechanically but using wooden churners or wooden ghani machines.
- The seeds are crushed using minimal or no heat, usually at temperatures ranging from 40°C to 50°C.
- Wooden parts are used in the extraction process, which is considered safer for our health.
- The quantity of oil obtained from cold pressing is lower compared to hot-pressed oil.
- Cold pressing requires more manpower as it involves the use of expellers, screw conveyors, and other manual parts.
- Cold-pressed oil retains a higher nutritional value compared to hot-pressed oil.
- The aroma of cold-pressed oil is quite prominent.
- The acidic value of the oil is low, eliminating the need for additional refining.
- Refined oil is produced using a chemical process.
- High temperatures are applied to treat the oil.
- The entire process is based on chemical treatment.
- The nutritional value of refined oils is negligible.
- Refined oils have lower viscosity and thickness compared to pressed oils.
- Preservatives and chemicals are added during the refining process.
Below table provides a summary of the key differences between cold-pressed oil and regular hot-pressed oil, covering aspects such as extraction process, nutritional value, aroma, quantity of oil, acidity, additional refining, production manpower, health considerations, cooking suitability, deep-frying suitability, shelf life, and storage requirements.
|Aspect||Cold-Pressed Oil||Regular Hot-Pressed Oil|
|Extraction Process||Mechanical with minimal heat||Mechanical with high heat|
|Extraction Equipment||Wooden churners or ghani machines||Metallic extraction machines|
|Quantity of Oil||Lower||Higher|
|Additional Refining||Not required||Often required|
|Production Manpower||More manpower required||Less manpower required|
|Health Considerations||Safer for health||Potential health risks from iron parts|
|Cooking Suitability||Medium to low heat||Medium to high heat|
|Suitable for Deep-Frying||Not recommended||Yes, after refining|
|Shelf Life||3 to 4 months||Varies depending on refining process|
|Storage||Dark places to maintain quality||No specific requirements|
Pros and Cons of Using Cold-Pressed and Hot-Pressed Oil
Hot-pressed oil generally has a strong fragrance and flavour, which is more noticeable in oil plants rich in oil content such as sesame seeds and peanuts. However, when such hot-pressed oil is cooked without proper treatment, it tends to foam and overflow. To address this issue, the oil undergoes a filtering process and is refined using centrifugal oil filters.
On the other hand, cold-pressed oil has a minimal smell and lighter colour, retaining the original flavour of the oil plants. It is particularly suitable for oils derived from grapes, olives, linseed, and other oil crops. Cold-pressed oil does not foam while cooking.
Cooking Differences Using Cold-Pressed Oil
Cold-pressed oil, due to its minimal extraction process and low heat application, is very convenient to use and offers numerous health benefits. It does not foam when heated and remains natural. It has low cholesterol and is free from harmful chemicals.
This type of oil is not oxidised and retains antioxidants, making it beneficial for preventing cancer, aiding in weight loss, maintaining oral hygiene, conditioning the skin, and more. Cold-pressed oil is rich in phosphates, cholesterol-free, and offers additional health benefits such as relief from constipation, improved brain health, and better blood sugar levels. Due to its low smoke point, cold-pressed oil is best suited for cooking at medium to low heat.
Can We Replace Regular Cooking Oil with Cold-Pressed Oil?
While replacing regular oil with cold-pressed oil may be expensive and challenging, making this small change can have a significant impact on your well-being. When using cold-pressed oils for cooking, it is important to treat them on low to medium heat only. Deep-frying with cold-pressed oils is not recommended as it can lead to the breakdown of unsaturated fats. Many people are switching to cold-pressed oil due to its great taste and flavour. Some preferred cold-pressed oils include olive oil, groundnut oil, sunflower oil, coconut oil, and walnut oil.
In conclusion, it is evident why cold-pressed oils are gaining immense popularity as a healthy substitute for refined oils. When introducing cold-pressed oil into your diet, it is advisable to do so gradually, as the body may take some time to adapt after being accustomed to refined oils for an extended period. Cold-pressed oils do not contain harmful preservatives and should be consumed within 3 to 4 months. They should be stored in dark places to maintain their quality. Each variety of cold-pressed oil serves a specific cooking purpose and offers different health benefits. Consider switching to cold-pressed oil from refined oils and experience the positive effects it can have on your body.