The writing is on the wall when it comes to waste. We need to improve our efforts from a government level, societal level and we each need to take responsibility. Over one-third of the world’s food is wasted. In hotels and restaurants, a tonne of food waste costs that business between €3,000 and €5,000. An average restaurant loses about €24,000 per year from food waste and an average hotel loses about €150,000 per year, according to the Environmental Protection Agency (EPA).

One of the most simple ways to reduce food waste in a kitchen is to reuse as much as possible. For centuries, cooks have been making stock from leftover vegetables – nothing new there – but now these cut-off vegetables are becoming a star on the plate as root to stem eating is a highlight on many top restaurants’ menus. More restaurants and chefs are looking to reduce their food waste and creating innovative ways to do so.

Overends Restaurant in Airfield Estate, Dundrum, grow their own vegetables and fruit to supply the restaurant and food waste is used for compost, which again fertilises the farm. A perfect cyclical approach to sustainability.

In Michelin starred restaurant Heron & Grey, chefs recently created a menu to use up everything they had left and stored in the freezer to ensure they had used up all food before closing the restaurant until next season.

In Galway, chef Jess Murphy and the team at Kai Restaurant were recently awarded a three-star sustainability rating from the Sustainable Restaurants Association, which lists them in the top 20 most sustainable businesses. The restaurant has a 93% food waste rating, diverting 100% of its waste from landfill.

In Dublin, John Wyer of Forest Avenue, says it comes down to how much you can realistically do while also sustaining the business.

“We have a great opportunity to use up a lot of food because we give snacks at the start of meals. For example, on the lunch menu, there are always trimmings of vegetables and you have fish belly and salted cod croquettes, with kohlrabi and smoked mayonnaise. You’re turning a negative into a positive. Customers aren’t expecting it, so there is a sense of perceived value and making the offering more generous.”

“We always work with whole animals and use the entirety of them. We take pigs’ heads; they are salted, braised and broken down and that’s turned into a snack of a pork rye at night time. Fermenting is a great way of using up whole vegetables, stems of spinach and chard can be fermented and turned into something exceptional. The stems of wild garlic can be pickled and chopped like chives and turned into a beautiful garnish.”

“Dehydrating is another very good technique; we dry the stems of herbs, trimmings of vegetables – cabbage, roasted onions – and use those as seasonings. We take the pork pie mix and season it with a powder of roasted onion or cabbage enhancing the flavour and increasing the umami flavour. We do the same with mushrooms and that powder is used on pasta dishes. We even make soap out of beef fat and that’s used in the toilets.”

But as John explained, you can only do so much realistically. “This is a small kitchen. All of a sudden you have filled the cold room and prep room with containers of stems and cabbages – it’s not sustainable. We run out of containers and then there’s almost none for mise en place!”

“You also have the conflict of having a no waste ethos and trying to sustain the business. Your chefs will have their hands full just trying to get set up for service and if you’re asking them on top of that to breakdown the stems of vegetables, in a way you are adding to the workload.”

In Cork, Justin Green in Ballyvolane House has found a unique way to further add to his business but also his sustainability ethos at the same time. “We basically operate at zero waste. We always have, I mean it is nothing new to us and I feel very strongly about it,” explained Justin.

“Our gin is the latest way in which we are being sustainable, in that the alcohol we use to make our gin is made from a bi-product from food production, whey. Whey was a real problem in the cheese industry for years. Carberry Group in Cork created a yeast that ferments the whey to produce an alcohol. This is what we use to make our gin.

“It’s very evocative of our terroir because the farmers give the milk to Carberry who make cheese from it and produce alcohol from the whey and sell it to us. It is a product that is a valuable commodity with very good environmental credentials and that is really important to us.”

“At the moment I am even trying to be closer to zero waste in the distillery by looking at how we can give our heads and tails that we don’t use, which are again a bi-product of our gin production to an anaerobic digestion company in Kildare. If we can then that would be amazing.”

In Dublin, Locks have been experimenting with pigs and reducing their food waste bill also. Chef Jeremy Cuevas started in the restaurant last year and proposed an idea to owners Paul McNamara and Connor O’Dowd that has had some surprising results.

“When I started here last year, I noticed that we have four bins in the back for food waste. It is actually quite expensive in Dublin to get rid of all that waste and I thought, ‘what can do about the waste?’,” Jeremy told me.

“I was lucky when I moved here with my girlfriend that we moved to one of her family’s farms, in north county Dublin, and we maintain it for them. The farm used to be a dairy farm and there is a pig farmer down the road from us in Trim, so I bought four pigs from him. We started taking anything that’s not meat in the restaurant and putting it aside for the pigs. We got new buckets and sterilised them, which are our ‘pig buckets’ and at the end of prepping and every night, we put everything in there for me to take home.”

“The pigs are really happy and well fed. We bought them when they were eight weeks old and they probably weighed about 20kg and now they are 120kg each! They’re great!”

“The ‘pig project’ in Locks is a great idea and one I’m sure that more restaurants could adopt if they were able to link in with farms.”

“When I had this idea of getting some pigs, I asked Paul and Connor if it was cool to start bringing home food waste to feed them. We said the deal was then that we would share the pigs, two for me and two for the restaurant. The pigs cost us €60 each. If you are monetising the food waste, we are taking three bins home a week, which is €30 a week savings and I am feeding them for free essentially.”

And what about the benefits for the restaurant? Co-owner, Paul McNamara, explained to me how much exactly their ‘pig project’ helped against their food waste bill. “It costs €9.50 a bin to empty it, so it was costing us €40-€50 a week and it’s now costing us €10. Jeremy has had the pigs for about eight months now, so that’s €30 for 32 weeks, approximately, which is just short of €1,000 saved on food waste. It’s great!”

“We’re going to hold a dinner in the restaurant at the end of June. It will be a special event with a set pig menu, every course might be a different part of the pig. They’ve been eating lots of carrots, beets and parsnip tops and apples from the orchard, so the menu will mimic what they ate too.”

“It’s been a great exercise for us. We don’t like to waste anything and try to be as sustainable as we can. It’s not really about the money though, I mean it is a relatively small saving, but for us it’s more the practicality and ethical nature of food waste that we wanted to try and improve on. The fact that someone has gone to so much trouble to grow and produce vegetables and we just put a high percentage of that straight into the food bin. It’s nice to put it to a use. We are feeding something that we are going to inevitably use and eat.”

Dee likes to describe herself as a professional eater! Taught to cook by her father and sisters at a young age, starting a life-long passion for cooking and the enjoyment of food. Soon after qualifying as a journalist, she began a career writing about food and travel.

Her passion for Irish food and the people behind it – those who grow, produce and cook – has only been amplified over the years and led her to many roles in the industry including; member of Irish Food Writers’ Guild, chair of Slow Food Dublin, organiser of Slow in the City food festival, curator of Food on Board at Body&Soul Festival, and a judge of Blas na hEireann and Food&Wine Magazine Restaurant Awards.