Never underestimate the Consequences of “Re-purpose used Cooking oil” (RUCO)

Oil is a major ingredient in most Indian cooking traditions. Oil is used for cooking and to add flavour to your food. However, choosing the correct cooking oil can save you from heart disease, cholesterol blockages, stoutness and processing issues. There is abundance of oil options can cause confusion about which oil may be the healthiest ones to use. All cooking oils are composed of three different types of fatty acids: monounsaturated fats, polyunsaturated fats and saturated fats. All oil is categorised based on which type of fatty acid is the most prominent in it. The oil can be used in different forms of cooking such as frying, seasoning and grilling. It is considered healthy owing to its high content of mono and polyunsaturated fats, which in turn help in lowering LDL “bad” cholesterol. Monounsaturated fatty acids like Omega-3 give olive oil its anti-inflammatory properties. Reusing cooking oil in food preparation, especially during deep-frying, is a common practice to save costs. Consumption of repurpose used cooking oil (RUCO) has been a regular practice without knowing the harmful effects of using it. Repeated heating of the oil accelerates oxidative degradation of lipids, forming hazardous reactive free radicals and reducing the natural antioxidant contents of the cooking oil which further leads to lots of health problems.

What are health risks when using re-purpose used Cooking Oils?

To reduce the expenses, the oils tend to be used repeatedly for frying. When heated repeatedly, changes in physical appearance of the oil will occur such as increased viscosity and darkening in colour which may alter the fatty acid composition of the oil. Heating causes the oil to undergo a series of chemical reactions like oxidation, hydrolysis and polymerization eventually resulting in lipid peroxidation. During this process, many oxidative products such as hydro peroxide and aldehydes are produced, which can be absorbed into the fried foods and thereafter enter the systemic circulation after ingestion. Consumption of repeatedly heated cooking oils is associated with increased risk of hypertension. The accumulation of fats chronic intake of heated cooking oils increases the risk of cancer and cardiovascular diseases. The intake of repeatedly heated palm and soybean oils significantly increased the blood pressure. 

What is Smoke Point at Which Oil Becomes Harmful?

Smoke point is the temperature at which cooking oil starts to give off harmful smoke, which begins to produce a continuous bluish smoke that becomes clearly visible, dependent upon specific and defined conditions a certain sign that the oil has turned useless and must be discarded immediately. The more refined oil, the higher its smoke point, because refining removes impurities and free fatty acids that can cause the oil to smoke.

Common Oil	Smoking Points (in °C)
Safflower Oil, Refined	266°C
Mustard Oil	254°C
Soybean Oil, Refined	238°C
Corn Oil, Refined	232°C
Coconut Oil	232°C
Groundnut Oil	232°C
Sunflower Oil, Refined	227°C
Almond Oil	216°C
Sesame Oil	215°C
Virgin Olive oil	199°C

Potential health risks of reusing Cooking oils include:

1. The oil gets to become more carcinogenic

Anything that is carcinogenic has the possibility of causing cancer. The researches have shown that aldehydes, toxic elements - that are produced when you reheat oil. Cooking food by reusing cooking oil can also increase free radicals in the body, which can cause inflammation - the root cause of most diseases including obesity, heart disease and diabetes. High inflammation in the body can also reduce immunity and make you prone to infections.

2. It increases LDL cholesterol

Food cooked in black, smoked oil which is being used and reheated throughout the day can increase level of LDL or bad cholesterol in the body. High levels of LDL cholesterol can increase risks of heart disease, stroke and chest pain. Avoid reusing cooking oil to avoid cholesterol-related problems.

3. More acidity

Reheated cooking oils may cause the burning sensation in your stomach and throat. Avoid eating roadside junk and deep-fried food if you experience more acidity than usual.

Some other health risks are as:

• Obesity
• Weight gain
• Diabetes
• Heart disease
• Alzheimer s and Parkinson s disease
• Irritable throat (due to inhalation)

According to the latest circular by FSSAI, all food business operators whose consumption of edible oil for frying is more than 50 litres per day are liable to maintain the records and dispose of used cooking oil to agencies authorised by FSSAI from time to time. This new rule will prohibit them from using the same cooking oil for more than three times. It has been found that reusing such oil is bad for human heart and body. Repeated frying and usage of edible oil changes its physio-chemical and nutrition properties and leads to the formation of TPC, which makes it unfit for human consumption. The maximum permissible limit of total polar compound (TPC) in edible oil at 25 per cent. 

According to the FSSAI these are the guidelines to avoid reusing cooking oils. 

How can we use RUCO in a correct way?

Ø  Oil once used for deep frying foods should be filtered and may be used for making curry preparations in order to make it economical. Avoid using the same oil for frying.

Ø  UCO should be disposed of when blue-grey smoke appears or tough foam gets formed or oil becomes dark and murky or the consistency of the oil changes.

Ø  These are some of the indications of the deteriorated quality of the oil.

Ø  Do not refill the fresh oil container with UCO. Store it separately.