"I'm really thrilled with the result," Ms Swift said. "It was an extremely tough competition and it's been such a great opportunity for me."
She qualified for the national title events, which included wine judging, laboratory skills, technical exams and presentations, by taking out the regional title earlier this month. She said it had already opened some doors for her and helped her grow in confidence.
"I look forward to doing this title proud in the year ahead," she said, adding she was grateful for the support Ash Ridge, the event sponsors and the organisers had given to the event - "and me personally".
Young Winemaker of the Year chairwoman Sophie Matthews said staging a national competition had been long overdue and it had been a huge success.
"New Zealand's young winemakers are getting the deserved recognition from their industry peers," she said.
Mr Dennis said when he heard he had won the Young Viticulturist of the year title he was "lost for words".
"I was absolutely delighted because you never know how you're doing in these competitions," he said, adding that while it was "pretty daunting" when he started the series of challenges he felt comfortable in his abilities as they progressed.
Mr Dennis beat three others for the title and took part in a wide range of events and exercises over three days.
While modest about his win he had "put in a lot of hard work" and it was good feather in his cap. "It makes people realise you know what you're talking about," he laughed.
As there was when Ms Swift took her title, there was a huge "home crowd" cheering when Mr Dennis got the nod.
Due to the win, he is now lined up for the New Zealand Young Horticulturist of the Year title coming up in Auckland.
But before that it was "back to the office because I've got a bit of catching up to do".
Mr Medina said the wins capped off what had been a great Romeo Bragato conference which had drawn about 500 people, including wine industry representatives from the UK, France, Australia, South Africa and the United States.
The guest speakers included Olivier Yobregat of the French Vine and Wine Institute, University of Pretoria Professor Gerhrard Pietersen, University of California Napa Valley farm adviser Dr Monica Cooper and Melanie Brown of the New Zealand Cellar online store.
"I have had some great feedback from many people and it has all gone really well," Mr Medina said.
"It's been a number of years since we have staged it here and are proud that we have put on a great event and got such a great attendance."