Before a meeting on the development of the commercial fishing industry, Mr Putin visited Nord-West F.C., a leading producer of fish products.
Vladimir Zimnitsky, the director general of the company, described fish processing in detail to the prime minister.
"We produce 400 kinds of frozen and refrigerated fish products," Mr Zimnitsky said.
The plant's director added that the company had spent two million euros on upgrading production. Thirty percent of this amount came from the company's own funds and the rest was financed by Sberbank.
The prime minister was also shown a packaged refrigerated cod that will keep for up to 14 days.
"I'm taking it with me," the prime minister joked.
Nord-West F.C. primarily supplies the domestic market, but it also exports to countries round the world, including Canada, France, Germany, Moldova, Norway, Ukraine, the UK and the US.
In 2006-2009, the company received state aid in the form of subsidised interest rates on loans. The company employs around 250 personnel.