What is your philosophy when it comes to glassware?

Many companies have the resources to make the material glass. But we are not making glass to be interesting or beautiful; for us, everything is about functionality. We make great wine glasses; some of our competitors, I know, don’t even drink wine.

How do you settle on a shape for a wine glass aimed at a specific grape varietal? 

Let’s say we are developing a glass for a grape that is not so well know, such as saperavi. It’s native to Georgia and popular in Eastern Europe. I ask the winemakers to pour their wine into our existing glasses and see which they feel is the closest to ideal. Meanwhile, I learn from them about the different styles of that wine – should the glass I design promote acidity, minerality, or a floral component, for example. I start producing prototypes and fine tuning. There is always a lot of back and forth.

How People have expressed scepticism about the need for a specific glass for every grape…

Well, I would have agreed with them 10 or even five years ago, but there is less scepticism now. That’s because we are constantly hosting tastings around the world – with diehard connoisseurs, with the wine trade and, most importantly, with winemakers – and we have gained a huge following. I pour the same wine into four different glasses and they experience how different smells, tastes, and feels in the mouth (which is so important, but people rarely speak about) in each one. And it can wow not only newcomers to wine but also those who believe they know everything.

In a family business that has been running for over 250 years, do you avoid those frictions that can occur as responsibility is handed on to the next generation?

I don’t think it matters whether it’s the second or 20th – every generation is challenged by the times. My father was smart enough to send me far away when I was really developing my own ideas, between the ages of 35 and 45. He gave me the opportunity to run my own market, the US, and wanted to be impressed. And even in a family business, you can take the decision to hand it over to a third party, if you think that will be better for the company than passing the torch. But I passed the test and now I make the decisions, but I respect the way he developed the company, so I am happy to have him there for guidance and support. For sure, there are still moments when we clash. But we are lucky because other families have more personal reasons to clash, which mix in with the business friction; we only have clashes over business decisions.

Riedel has a reputation for handblown glass, but you seem equally proud of your machine-made glasses, such as the new Veloce range. You’re not worried that dilutes the luxury element of your brand? 

We sell 60 million glasses every year; not enough people are willing to work in a factory to produce them by hand, so we have developed our own equipment to produce these glasses – there’s no market for, say, Siemens to manufacture glass-making machinery. And the quality of our machine glass is so good, only a glassmaker could tell the difference – you cannot feel, let alone see, a seam on the glass. Veloce is the thinnest, lightest machine-made glass in history. It has the widest base a machine can produce – 10cm rather than the usual 7cm. Each one has the grape variety written on the base because consumers said they needed a reminder which glass is for which wine. Sommeliers hate them – because they can’t get away with a mistake!

I’ve seen alpha males showing off their flexibility of their favourite glass brand by squeezing it. How do yours do in the squeeze test?

Please, please, don’t do it! It says nothing about the quality. All you do is squeeze it without knowing how far it will go and, if it shatters, you almost certainly cut your hands. I know because I used to do it when I was younger. Stop squeezing glass, guys. I want to sell more glasses because people recommend Riedel to their friends, not because people are replacing glasses they’ve broken.

Apart from not deliberately breaking them, what other advice do you have about caring for wine glasses at home?

I was my glasses by hand, but there is no reason why they can’t go in the dishwasher. If you are hand washing them, cover and protect your hands with two Riedel polishing towels, then clean from the base, up the stem and then on the outside and the inside of the bowl, holding the glass on its side. You only need warm water and a little soap, especially inside the glass, because hardly any grease gets in there. After dinner, you can just fill them with water and leave them overnight, before washing the next day.

Is storage important? 

Yes, never store you glasses is a wine cellar. Humidity is your glasses’ worst enemy. The same goes for a steamy kitchen. Steam works itself into the surface of the glass and erodes it. Kitchen cabinets are either infused with odours from food or are coated in lacquer – that’s what causes your glasses to go cloudy. If you don’t have an alternative, make sure you rotate your glasses – most people get a set of six or eight, but most weeks it’s only two of you drinking, so you use the same glasses. And when you reach to the back at Christmas, your wonder why the glasses look so bad.

And how about before pouring wine into them?

Yes, I like to prepare my glasses for wine. I pour a drop into one glass and coat the inside of the glass, then pour that into the next glass and do the same, and so on before finally discarding what remains. That way, you eliminate any unwanted odours in the glass. And you should do the same for your decanter, too.

Riedel Veloce glasses are available for cabernet/merlot, syrah/shiraz, pinot noir/nebbiolo, sauvignon blanc, riesling, rosé, chardonnay, and Champagne, £62.50 a pair; riedel.com