Fat, Oils and Grease or FOG as they’re known

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Fat, Oils and Grease – or FOG as they’re known – are the core and essence of any fast food takeaway. FOG is what gives the fast cooking time, and more importantly the great taste, to the fish, burgers, chips, and nuggets that you serve and that customers keep coming back for.

But getting FOG right involves taking decisions on product, equipment and waste disposal. Does your oil/lard have the right taste? A good shelf life? Are you using the right kind of fryer? The right filter? Are you compliant with waste disposal requirements and can you prove it? Does your staff know how to manage frying and disposal? These are the kind of questions all fast-food owners have to take decisions on.


For decades, takeaways in Ireland were run on dripping – beef tallow, which can be frequently re-used, is stable at high temperature and gives a great taste. While many takeaway owners remain fans of dripping, many have moved away from it. Johnny Soave, owner of Giovanni’s explains why:

“Dripping is a great way of frying chips but the smell of frying is strong and also it ‘coats the tongue’. Customers liked that but then about 16 years ago tastes began to change. People wanted something lighter, which didn’t stay on the tongue – they saw that as healthier, and they didn’t like going into chippers where the smell of frying was strong. So I – and many others – changed from dripping to other cooking fats.”

Takeaway owners can now choose between vegetable oils – like palm, soja and rapeseed – which are stable at high temperatures, or hybrid oils which combine vegetable and beef fats. Frylite sells seven fats and oils suitable for high temperature frying, while Pure Oil lists 17 different products, including specialised oils.

Different FOGs can interact differently with different food products, and of course the right FOG for you depends on the volume of business and turnover. Talk to your suppliers about what works.

“Frying oils vary widely in terms of price, performance, taste and fry life,” says Olivia Shuttleworth, brand manager for Prep, a high-performance frying oil. “When selecting an oil, it’s important to think about your deep frying habits – how frequently you fry, the volume of frying you do and the types of foods you’re going to be cooking.”

Also of course pay attention to customer tastes and to media reports. Two years ago, the US Food and Drug Administration banned the use of partially hydrogenated oils in food, and some consumers have concerns about the environmental costs of palm oil. Today we’re frying with oils that were barely heard of twenty years ago. Tastes change rapidly. If you’ve gone to the trouble of sourcing high-quality, light oil with a good environmental footprint, make sure you let your customers know.


The technology around deep fat fryers is constantly evolving. Look out for models with in-built filtration systems as this can extend the life of the oil being used. Pumped filtration is another innovation that allows oil to be filtered in just five minutes even when it’s hot.

“Units which feature auto filtration and an integrated oil quality sensor enable operators to filter the oil at the push of a button when prompted”, explains Steve Hemsil CFSP, sales director for UK and Ireland at the foodservice solutions company, Welbilt. “Not only will this produce outstanding frying results, but it will also use up to 40% less oil and 10% less energy than previous models”.

Helen Applewhite, marketing manager at Linca, a leading UK manufacturer of catering equipment notes that in recent years, they’ve seen a definite shift to ‘green’ equipment: “Customers realise that a fryer which is energy efficient can save significantly on fuel bills”.

Ascertaining the correct time to change oil is essential: too late and the taste will be awful and may even make customers sick; too early and it’s money down the drain. There are now electric oil testers on the market which can apparently determine the right time to make the change, but seasoned takeaway owners probably don’t need these – they develop a sixth sense on when oil needs changing.

If you’re using the new, lighter FOG, that means changing more often. Says Johnny Soave: “with dripping, you could go two weeks, even three before changing; with the newer fats it’s every five or six days. If you leave it longer than that, the chips will boil, not fry, and the taste will be effected.”


In 2013 a ‘fatberg’ the size of a double decker bus was discovered in the sewers beneath London. It took sewerage workers three weeks to clear it and they only narrowly managed to prevent an environmental disaster for the cluster of food businesses in the streets above. Fatbergs are formed by tonnes of fat, cooking oil and grease being flushed down sinks where they meet cold sewer water and congeal into solid matter that mixes with other underground waste to form giant fatbergs.

In 2007 Dublin City Council (DCC) started to impose Trade Effluent Discharge Licences on a minimum of two thousand food service establishments. On RTE Television News, in 2007, one of their senior engineers – Mr. Batty White – claimed that the cost to the Local Authority, for clearing blockages caused by grease in the main drain, amounts to €500k per annum. The approach of licencing the producers of the waste – the catering industry – was one of the first of its kind undertaken by a local authority in Europe and since its introduction has prevented the sector as a whole from sailing into dangerous fatbergs.

As a takeaway using high volumes of fats and oils, you are legally obliged to have a Trade Effluent Discharge License and to manage the use of fats and oils.

The owner of a restaurant needs to apply for a licence – that has an initial cost and there may then be an annual charge, depending on which local authority controls your area. In order to get the licence the restaurant must comply with the terms and conditions which include maintaining a system for removing FOG from waste water. Your local authority will inform you of the conditions and also carry out inspections to enforce compliance.

Tasty Eating spoke to local authorities in each province – Dublin, Cork, Galway and Monaghan – and found that only Dublin had a fixed annual fee, the others take each licence on a case by case basis and decide then what the annual fee would be.

Dublin City Council will provide any information needed about getting the restaurant inspected and how to apply for and comply with a licence. They also will provide a list of installers and servicers of grease traps. In addition, they have information on firms that will remove waste oil free of charge for use in recycling. Initially, businesses are inspected four times a year but this will be reduced if an outlet has a history of compliance.

For an independent fast food restaurant, the FOG removal system is usually a grease trap of some kind. There are plenty of firms that will install and maintain a FOG removal system – the cost varies depending on the size of the outlet but typically they start at €1000. Dublin City Council’s Michael O’Dwyer estimates the cost for a Fish and Chip outlet to be around €2200. The costs for cleaning and servicing depends on the size of the business.

The right grease trap for your business is essential. “A combination of bioremediation, grease removal units, and grease traps maximises the opportunity to eliminate the problem of FOG entering the sewers,” says Keith Warren, director of the Catering Equipment Suppliers Association, CESA.

When it comes to disposal, for many takeaways, the simplest solution is to use a company like Pure Oil of Frylite which handles the disposal for you. Both Pure Oil and Frylite offer a complete all-in-one service delivering fresh oil and removing waste oil at the same time. The waste oil then goes to recycling plants.

Pure Oil was shortlisted for the Green Business Award and customer, Pichet Restaurant in Dublin, is “happy that the oil is being disposed of in a way that is environmentally friendly’

George McCarthy, sales manager of Frylite says “We have customers all over Ireland. I think everyone now knows that they have to be compliant with waste removal. Luckily, there are more takeaways doing it right than wrong, and we’re here to help those who want to do it right.”


Familiarising your staff with the ways of FOG is one of the most important training you’ll do. They need to know the temperature to cook at, how to handle the equipment, when to change the oil and how to dispose of it.

It’s vital that every member of staff is trained to ensure safety, efficiency and maximum productivity. Today, most manufacturers offer free training with the equipment. You should take them up on this.

With premium products, quality equipment, smart cooking methods and excellent staff training, a business can handle their FOGs responsibly and ensure that they get good press about their food and their waste footprint. Deep-fried food remains hugely popular but consumer interest in health and environmental issues continues to impact on the restaurant sector – making it essential for fast food outlets to demonstrate their good intentions and responsibility.


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