What is the difference between hot pressed and cold pressed sesame oil

There are significant differences between cold pressed sesame oil and hot pressed sesame oil in multiple aspects, as follows:

Craftsmanship

• Cold pressed sesame oil: also known as raw pressing method, refers to the oil pressing process in which the oil is not heated or slightly heated before pressing, and is sent to an oil press for pressing at a low temperature (usually below 40 ℃). The extracted oil has a lower temperature and acid value, and generally does not require refining. After precipitation and filtration, the finished oil can be obtained.
• Hot pressed sesame oil: Before pressing oil, the oil is first sorted and crushed, and then subjected to high-temperature heating treatment (usually above 60 ℃) to remove impurities, moisture, and other substances before pressing. After the oil is cooked in a wok, it is pressed. The cooked oil is edible and has a strong aroma and flavor.

Extraction rate and yield

• Cold pressed sesame oil: The extraction rate is relatively low, only about 20%, so the yield is also relatively low.
• Hot pressed sesame oil: The extraction rate is relatively high, reaching about 35%, so the yield is relatively high and the price is usually low.

Flavor and Taste

• Cold pressed sesame oil: On the basis of retaining the original sesame aroma, it is more fragrant and has a mellow taste. Compared to hot pressed oil, the taste is lighter and can be described as “fragrant”. Meanwhile, cold pressed sesame oil has a sesame like, earthy, sawdust like, and grassy flavor, mainly derived from hexanal, nonanal, and n-hexanol.
• Hot pressed sesame oil: It has a rich flavor and a strong aroma, and is loved by a large number of consumers. It can be said to be a ‘strong aroma type’. At the same time, hot pressed sesame oil has a roasted sesame flavor, roasted nutty fruit flavor, and burnt aroma, with flavor compounds mainly composed of Maillard reaction heterocyclic products.

nutritional value

• Cold pressed sesame oil: As oil is extracted at low temperatures, it can retain a large amount of nutrients such as vitamins and trace elements, including anti-aging vitamin E and physiologically active substances such as sterols that have skin health benefits and enhance human metabolic function. In addition, the sesamin in cold pressed sesame oil has also been preserved intact. Sesamin has unique effects on liver protection, kidney protection, prevention of “three highs”, hair growth, vision improvement, and anti-aging, which are beneficial for health care.
• Hot pressed sesame oil: After high-temperature treatment, the crude oil extracted from the oil has a darker color and higher acid value. Bioactive substances such as vitamin E and alcohol carotenoids are greatly lost during the pressing process, resulting in resource waste.

other characteristics

• Cold pressed sesame oil: It has natural characteristics and avoids the adverse effects of traditional high-temperature oil pressing processing. At the same time, cold pressed oil has a lower smoke point, is less likely to clog the pot, and has a clearer color, which is better than hot pressed oil. However, the moisture content of cold pressing is unstable and not conducive to long-term storage.
• Hot pressed sesame oil: Due to high-temperature treatment, its color, flavor, and other aspects may undergo some changes, but this is also a part of its unique flavor.