Although it was already a leading player in its field, the company was constantly striving for growth and innovation and was continuing to invest in research and development, he said.
Judges said Tru-Test had made sure its brand was represented and positioned correctly across different countries.
"Its broad and diverse geographic presence and strategic outlook, together with its active and ongoing merger and acquisition activities, are equally valuable assets," the judges said.
Earlier this year, Tru-Test Group bought milk storage and refrigeration firm Dairy Technology Services for $73 million.
That purchase followed on from its $1 million acquisition of Radian Technologies in December last year, as it looked to offer more integrated support for dairy farmers.
Tru-Test also took out the award for Best Business Operating Internationally in the over-$50 million category.
Greg Muir, managing director of Tru-Test, said the win showed New Zealand could be a better place for manufacturing than China.
The company has brought most of its manufacturing back home from China.
"When we decided to continue to manufacture in New Zealand we knew it meant competing on the international manufacturing stage," Muir said.
"The only way to do this was with an absolute commitment to adopting new ideas, maximising efficiency and minimising waste."
Christchurch company ARANZ Geo - which develops 3D geological modelling solutions for the mining, hydrogeology and geothermal industries narrowly missed out on the top award and received a special commendation from judges.
ARANZ Geo took home the award for the Best Business Operating Internationally in the under-$10 million category.
Software company Gentrack won in the $10 million to $50 million category.
Brett Hewlett, the head of Comvita, was named the country's top international business leader.
John Brakenridge, chief executive of The New Zealand Merino Company, won the award for Outstanding Contribution to International Business.
2013 New Zealand International Business Awards Winners
JUDGES' SUPREME AWARD FOR INTERNATIONAL BUSINESS
Tru-Test Group
SPECIAL COMMENDATION
ARANZ Geo Ltd
ANZ Best Business Operating Internationally Under $10million:
ARANZ Geo Ltd
ANZ Best Business Operating Internationally $10m-$50million:
Gentrack
ANZ Best Business Operating Internationally Over $50million:
Tru-Test Group
Callaghan Innovation International Success through the Application of Innovation:
Buckley Systems Ltd
James & Wells Best Commercialisation of IP in International Business:
Auckland UniServices Ltd
AUT Business School Most Innovative Business Model in International Business:
Joint winner: JUCY and The New Zealand Merino Company
Best Use of Design in International Business:
3i Innovation Ltd
KPMG Outstanding International Business Leader:
Brett Hewlett, CEO, Comvita
KPMG Leader: Outstanding Contribution to International Business:
John Brakenridge, CEO, The New Zealand Merino Company Limited
