Exhibit 99.1

FOR IMMEDIATE RELEASE

SUNOPTA ANNOUNCES SECOND QUARTER 2011 RESULTS

Toronto, August 9, 2011 - SunOpta Inc. (“SunOpta” or “the Company”) (NASDAQ:STKL; TSX:SOY), a leading global company focused on natural, organic and specialty foods and natural health products, today announced financial results for the quarter and two quarters ended July 2, 2011. All amounts are expressed in U.S. dollars and results are reported in accordance with U.S. GAAP, except where specifically noted.

For the quarter ended July 2, 2011 the Company realized quarterly revenues of $290.8 million versus revenues of $233.9 million for the quarter ended July 3, 2010, an increase of 24.3% . This represents the largest quarterly revenues from continuing operations in the Company’s history, and reflects continued growth in the natural and organic foods sectors. Revenues increased 13.2% excluding the impact of the acquisitions completed late in 2010.

For the quarter ended July 2, 2011 the Company reported earnings per diluted common share from continuing operations of $0.07, or $4.4 million, as compared to $0.09, or $6.2 million, for the quarter ended July 3, 2010. The Company experienced continued strong performance in the International Foods Group and Opta Minerals Inc. offset by reduced earnings in the Grains and Foods Group primarily due to commodity market pressures in the sunflower segment, reduced earnings in the Ingredients Group due mainly to the loss of a major customer earlier in the year, and higher income taxes.

Earnings for the quarter ended July 2, 2011 reflect an income tax rate of 42.2% . The income tax rate is expected to normalize over the balance of the year to an annualized tax rate of approximately 36% due to the expected realization of certain tax benefits in the third and fourth quarter of 2011.

The quarterly results include other pre-tax income of approximately $3.2 million, due primarily to gains on the sale of assets in the Fruit Group during the quarter. These gains were offset by additional pre-tax costs of approximately $3.4 million included within the segmented results related to the Fruit Group disposals and other legal and rationalization matters.

For the quarter ended July 2, 2011 the Company realized EBITDA¹ of $12.9 million compared to $15.8 million for the quarter ended July 3, 2010.

For the two quarters ended July 2, 2011 the Company reported revenues of $551.7 million versus revenues of $450.6 million for the two quarters ended July 3, 2010, a year over year increase of 22.4% . Revenues increased 11.6% excluding the impact of the acquisitions completed late in 2010.

For the two quarters ended July 2, 2011 the Company realized earnings per diluted common share from continuing operations of $0.14, or $9.5 million, as compared to $0.16, or $10.4 million, for the two quarters ended July 3, 2010.

For the two quarters ended July 2, 2011 the Company realized EBITDA¹ of $28.8 million as compared to $29.8 million for the two quarters ended July 3, 2010.

At July 2, 2011, the Company’s balance sheet reflects a current working capital ratio of 1.47 to 1.00, long-term debt to equity ratio of 0.20 to 1.00 and total debt to equity ratio of 0.55 to 1.00. For the quarter ended July 2, 2011 the Company generated cash from continuing operating activities of $20.5 million as compared to $18.6 million for the quarter ended July 3, 2010. At the end of the quarter the Company had total debt outstanding of $167.8 million, a decrease of $17.8 million from the period ended April 2, 2011. At July 2, 2011 the Company had total assets of $631.4 million and a net book value of $4.65 per outstanding share. At July 2, 2011, the Company was in compliance with all its debt covenants.

Steve Bromley, President and Chief Executive Officer of SunOpta commented, “Our results for the second quarter reflect record quarterly revenues from continuing operations for the Company and continued growth in the natural and organic foods categories where we operate. Although we are working through a difficult commodity environment at this time, especially in our sunflower business, we continue to believe in our core portfolio and are focused on a number of new initiatives and opportunities that are currently in the pipeline. We remain committed to expanding our business in fast growing healthy foods categories while at the same time improving operating margins and returns on assets employed. We believe we are well positioned in the natural and organic foods sector and are confident in our future prospects.”

The Company plans to host a conference call at 10:00 A.M. Eastern Time on Wednesday, August 10th, 2011 to discuss the second quarter results and recent corporate developments. The conference call can be accessed via a link at the Company’s website at www.sunopta.com. Additionally, the call may be accessed with the toll free dial-in number 1-877-312-9198 or 631-291-4622. A replay number can also be accessed between August 10th and 17th with the toll free dial-in number 1-800-642-1687 or 706-645-9291 followed by pass code: 74437112#.

¹See discussion of non-GAAP financial measures following the consolidated financial information below.

About SunOpta Inc.

SunOpta Inc. is a leading global company focused on natural, organic and specialty foods. The Company specializes in sourcing, processing and packaging of natural and organic food products, integrated from seed through packaged products; with a focus on strategically significant vertically integrated business models. The Company’s core natural and organic food operations focus on value-added grains, fiber and fruit based product offerings, supported by a global infrastructure. The Company has two non-core holdings, a 66.4% ownership position in Opta Minerals Inc. (TSX:OPM), a producer, distributor, and recycler of environmentally friendly industrial materials, and a minority ownership position in Mascoma Corporation, an innovative biofuels company.

Forward-Looking Statements

Certain statements included in this press release may be considered “forward-looking statements” within the meaning of the United States Private Securities Litigation Reform Act of 1995 and applicable Canadian securities legislation. These forward-looking statements include, but are not limited to, our expectations about future income tax rates, our continued efforts to streamline our portfolio, our focus on growing our business and improving operating margins and returns on assets employed and our positioning in the natural and organic foods sector. The terms and phrases “continue”, “believe”, “expect”, “confident”, “enthusiastic”, “improving”, “remain focused”, “positioned”, and other similar terms and phrases are intended to identify these forward looking statements. Forward looking statements are based on information available to us on the date of this release and are based on estimates and assumptions made by the Company in light of its experience and its perception of historical trends, current conditions and expected future developments as well as other factors the Company believes are appropriate in the circumstances including, but not limited to, general economic conditions, consumer interest in health and wellness, product pricing levels, current customer demand, planned facility and operational expansions, competitive intensity, cost rationalization and product development initiatives. Whether actual timing and results will agree with expectations and predictions of the Company is subject to many risks and uncertainties including, but not limited to, global economic conditions, consumer spending patterns and changes in market trends, decreases in customer demand, potential failure of product development, working capital management and continuous improvement initiatives, availability and pricing of raw materials and supplies, and other risks described from time to time under “Risk Factors” in the Company’s Annual Report on Form 10-K and its Quarterly Reports on Form 10-Q (available at www.sec.gov). Consequently all forward-looking statements made herein are qualified by these cautionary statements and there can be no assurance that the actual results or developments anticipated by the Company will be realized.

For further information, please contact:

SunOpta Inc.

Steve Bromley, President & CEO
Tony Tavares, Vice President & COO
Susan Wiekenkamp, Information Officer
Tel: 905-455-2528, ext 103
susan.wiekenkamp@sunopta.com
Website: www.sunopta.com

SunOpta Inc.
Consolidated Statements of Operations
For the quarter ended July 2, 2011 and July 3, 2010
Unaudited
(Expressed in thousands of U.S. dollars, except per share amounts)

SunOpta Inc.
Consolidated Statements of Operations
For the two quarters ended July 2, 2011 and July 3, 2010
Unaudited
(Expressed in thousands of U.S. dollars, except per share amounts)

SunOpta Inc.
Consolidated Balance Sheets
As at July 2, 2011 and January 1, 2011
Unaudited
(Expressed in thousands of U.S. dollars, except per share amounts)

SunOpta Inc.
Consolidated Statements of Cash Flows
For the quarter ended July 2, 2011 and July 3, 2010
Unaudited
(Expressed in thousands of U.S. dollars, except per share amounts)

SunOpta Inc.
Consolidated Statements of Cash Flows
For the two quarters ended July 2, 2011 and July 3, 2010
Unaudited
(Expressed in thousands of U.S. dollars, except per share amounts)

SunOpta Foods has the following segmented reporting for the quarter ended July 2, 2011:

SunOpta Foods has the following segmented reporting for the quarter ended July 3, 2010:

SunOpta Foods has the following segmented reporting for the two quarters ended July 2, 2011:

SunOpta Foods has the following segmented reporting for the two quarters ended July 3, 2010:

¹Non-GAAP Financial Measures

In addition to reporting financial results in accordance with U.S. generally accepted accounting principles (“GAAP”), the Company provides information regarding Earnings before interest, taxes, depreciation and amortization (“EBITDA”) as additional information about its operating results, which is not a financial measure calculated and presented in accordance with GAAP. The Company believes that EBITDA assists investors in comparing performance across reporting periods on a consistent basis by excluding items that are not indicative of the Company’s core operating performance. EBITDA should not be considered in isolation or as a substitute for performance measures calculated in accordance with GAAP.

The Company defines EBITDA as “earnings from continuing operations plus provision for income taxes, interest expense, depreciation and amortization”. The following is a tabular presentation of EBITDA, including reconciliation to GAAP earnings, which the Company believes to be the most directly comparable GAAP financial measure.