Following this week's news that Kirin Holdings and Suntory are in merger talks, just-drinks has compiled five essential facts on the Japanese beer market.

1. Four companies - Kirin, Asahi, Sapporo and Suntory dominate the Japanese beer market. This week, Kirin Holdings confirmed it is in merger talks with Suntory Holdings, which would see the two companies controlling around half of the Japanese beer market.

2. Beer volumes in Japan continued to decline at a rate of more than 2% year-on-year in 2008, according to Euromonitor. Despite numerous new products in the economy beer segment (happoshu and new-genre products), consumers, especially younger consumers, continued to shift to RTDs and other alcohol drinks such as wine.

3. Due to the Japanese taxation system, the varieties of brewed malt beverages in Japan are categorised into two groupings: beer and happoshu. The distinction is made based on the amount of malt used relative to grain. Around 40% cheaper than beer, happoshu avoids high taxation due to its low malt content. Asahi's Honnama is a type of happoshu, and is made of barley extract and deep-sea water.

4. Beer in Japan has been around since Dutch traders introduced it during the Edo period. A Norwegian-American businessman established the first brewery in Japan, in Yokohama, in the 1870s, according to japanvisitor.com. This was eventually sold to a Japanese company that became the giant brewer Kirin.

5. The Dai Nippon Company split in two after the war in 1949, and Asahi Breweries and Nippon Breweries were formed. Nippon Breweries was eventually absorbed into Sapporo Breweries in 1964 following increased demand for Sapporo Beer.