Shares of SodaStream International Ltd. (SODA) are waterlogged in Wednesday morning trading after underperforming in the third quarter as compared to analyst expectations with some concerns surfacing about slowing growth for the home beverage carbonation system maker.

For the quarter ended September 30, Israel-based SodaStream reported revenue of $144.6 million, up 28.5 percent from $112.5 million in the third quarter of 2012.  Net income was $16.4 million, or 76 cents per share, compared to $16.8 million, or 80 cents per share, in the comparable quarter last year.  Adjusted income, which excludes the impact of one-time items, totaled $19.3 million, or 90 cents per share, up from $18.2 million, or 87 cents per share, in the year prior period.

Wall Street was expecting adjusted earnings of 72 cents per share on revenue of $145.2 million.

Sales in Western Europe, the top selling region for the company, grew 49 percent to $75.5 million from $52.6 million last year.  Sales expanded in the Americas by 29 percent to $49.8 million, while Asia-Pacific revenue declined by 21 percent to $8.6 million.

SodaStream manufactures and sells machines that let consumers carbonate water and flavor packs for homemade soft drinks.  Sales of soda maker starter kits increased 27 percent to 1.2 million units.  Carbon dioxide refill sales improved 34 percent to 1.5 million units and flavors sales grew by 7 percent to 514,000 units.

Gross margin was edged down 10 basis points at 54.1 percent.

Sales and marketing expenses were jumped 33 percent to $47.5 million, or 33 percent of revenue.  As a percentage of revenue, that was only a 110 basis point increase, which was part of a planned increase in advertising by the company.  General and administrative costs rose from $8.7 million to $12.7 million.

"We continued to execute against our primary objective of expanding our user base in our fastest growing markets during the third quarter," said Daniel Birnbaum, chief executive of SodaStream.

Looking ahead, SodaStream sees full-year 2013 revenue increasing 30 percent over 2012 to approximately $567.5 million.  Net income is expected to rise 23 percent to about $54.0 million.  Analysts were expecting earnings of $55.4 million on sales of $567.0 million.

Investors have reacted sharply to earnings guidance coming in below consensus estimates, mostly ignoring the better-than-expected earnings for the recent quarter.  Shares have sunk almost 10 percent in Wednesday action to $57.41 and are threatening to break below the 200 day moving average.  On the year, shares were trading ahead about 40 percent through Tuesday’s closing price of $63.75.