Stefanos Lianakis is the son of an agricultural scientist who specialises in food production.

The Greek co-owner of Mediterranean deli Sage & Relish has inherited his father’s evidence-based approach to quality.

Stefanos says the new shop and wholesalers in Western Road he owns with his partner Angeliki Zafeiropoulou stocks only products which pass high standards of chemical analysis.

“Suppliers will ask to send us a few samples and I will say let me see the chemical analysis first,” he jokes.

Stefanos still sends the chemical analysis of honey and olive oil over to his father to double check before the couple decide to stock a new line. But what are father and son looking for?

“Certain products such as olive oil deteriorate over time, so things like age, acidity, production style and type of storage matter a lot.”

In the Mediterranean they dissect olive oil like wine. Lower acidity levels and olive varieties will be on adverts so people know exactly what they’re pouring over their salads.

“People take it seriously. Because Britain is not an olive-producing country you don’t always have access to the info.”

When I visit the deli the couple opened in July, we sit at a tasting bar and Stefanos pours tasters of olive oil made with Greek Koroneiki olives and Spanish cornicabra olives. Out of 750 olive varieties these two have the lowest acidity levels.

“Lower acidity levels mean the olive oil will be higher in polyphenols, an antioxidant, which means better nutritional value. As acidity goes up the vitamin and nutritional value decreases.”

Sage & Relish imports items from tiny producers in countries including Greece, Portugal, Italy and Spain. Many producers have never exported produce before and their products are not available anywhere else in the UK.

Farmer Mrs Borou, for example, only took a license to ship her herbs from Greece’s Thesprotias region when Stefanos begged.

Angeliki says: “We want to be a delicatessen which is a real delicatessen in that we are seeking out small speciality suppliers and people who love what they do. These products are really special – even in their country of production.”

Angeliki moved to Britain to study 17 years ago. Stefanos arrived in 2009. Opening a deli in Brighton is the achievement of a long-term dream.

They sell locally produced items if they fit their aim to supply everything for the Mediterranean diet – the milk, cream and local cheese comes from Goodwood Farm.

By working directly with producers they remove the middle man, which helps keep prices down. It does mean however they have to close on Sundays and Mondays to unpack all the orders.

Stefanos brings over some honey from Melanon, a mountain in mainland Greece. It’s the first honey in Europe to be certified with a PDO – protected destination of origin – because the bees trace herbs into the mix. The fir honey is so low in natural sugars it will never crystallise. It is rich and viscose, sweet but not sugary.

The pine and thyme varieties taste hugely different. The wild thyme honey is stronger still. Angeliki says it’s Greece’s most popular taste.

“That is considered the king of honey. Our brand is from a small producer. He is a farmer. We have met him. For all of the things here we have met the people who make them. He is super happy it’s being sold in Brighton.”

Other rarities include Bee Good, a sweet honey and hazelnut spread, perfect for toast or with cheese or gamey meats, and the mastiha-based products, including water and honey.

Mastiha is a resin from mastic trees on the island of Chios. It is used to season products and is good for your digestive system, according to research published by Nottingham University.

Plans to roll out the wholesale side of the business in 2015 have been brought forward.

Chefs from CanTina Supper Club and Archipelagos are among those who already want to buy in bulk, suggesting the demand for the duo’s handpicked choices is there. “I think it’s because so many distributors all have the same products. Because we work with producers rather than distributors we have niche products.”

Sage and Relish, Western Road, Hove

Open Tuesday to Friday, 10am to 6pm and Saturday 10am to 4pm.

sageandrelish.co.uk