Delegat says costs relating to the purchase of an Australian wine company are partly to blame for its 40 percent jump in administration and finance costs.
The winemaker's profit for the six months ended December fell to $17.8 million from $19.3 million in the same six months a year earlier.
Delegat, which produces the Oyster Bay range, sold more than a million cases of wine globally in the six months, although that was 1 percent less than in the year-earlier six months.
Case sales in Britain, Ireland and Europe fell by 14 percent, but in America and Canada, where the company is concentrating its efforts, they jumped 15 percent.
The half-year revenue reached $121 million, down from $123 million the year before.
Chief financial officer Murray Annabell says the half-year increase in finance costs from $3.7 million to $4.2 million is made up of interest on borrowings. He says that since December 2012 Delegat has acquired about $80 million worth of assets financed through bank borrowings, so the interest is a reflection of a higher level of borrowing.
Mr Annabell says the firm has financed quite a lot of its acquisitions through its operating cashflows but debt levels are higher than they were at December 2012.
Delegat bought the Barossa Valley brand in Australia in June last year.
Mr Annabell says in the comparative period there were no costs associated with the Barossa acquisition, but this year there are $1.2 million of costs as a result of that.
The company is also developing vineyards in Marlborough and building a new winery in Hawke's Bay.