R&D: Reduced-sodium, Sun-dried Tomatoes -- November 2010

Sun-dried tomatoes add a sweet and savory flavor to an assortment of foods, like breads, cheeses, marinades, appetizers, spreads, pizzas and salad toppings. In addition to flavor, they add color and are a great source of the antioxidant lycopene. During the drying process, all of the components are concentrated, as compared to fresh tomatoes, including the lycopene. Sun-dried tomatoes’ highly concentrated sugars give off a sweet, deep, intense tomato flavor. Roma tomatoes make the best sun-dried tomatoes, because of their flavor, and also because they are meaty and firm. This results in more tomato to work with after drying.

Once dried, they are packaged in vacuum packaging or first roasted. Both the sun-dried or dried and roasted tomatoes are also available in pastes. The roasted sun-dried tomatoes offered only by Culinary Farms add a unique, smoky twist to foods. The conditions ideal for sun-dried tomato production are present only along the 38th parallel, in a special part of the Aegean Region of Turkey and in Northern California. Today, nearly all sun-dried tomatoes are produced in these two areas, while limited production occurs in Italy, China, Mexico and South America. Production processes vary greatly between the different areas.

Food preservation by means of drying dates back to the earliest recorded human history. For thousands of years, salt was used as a preservative. Sulfur, whose use as a wine preservative pre-dates Roman times, was found to be an excellent food preservative in the 18th century. At that time, sulfur powder was burned, creating sulfur dioxide gas. The sulfur not only helped control spoilage, but also retained the natural color of fruits and prevented browning.

When tomatoes are dried in the sun, controlling the microbial population is necessary to prevent spoilage, before the process is complete. In the processing of dried fruits today, especially overseas, sodium metabisulfite is often added as a preservative to extend shelf-life and retain color. This sulfur-containing compound is easy for processors to use, but has its disadvantages, primarily that of an increase in sodium levels of the finished product. “Recent studies performed by Culinary Farms, a California-based sun-dried tomato processor, demonstrated significant differences in sodium levels,” states Kirk Bewley, president of Culinary Farms.

Independent laboratory testing indicated Turkish sun-dried tomatoes contain 800-2,000mg of sodium per 100g of tomatoes. California sun-dried tomatoes, on the other hand, processed using gaseous sulfur dioxide, contain only the naturally occurring sodium, somewhere in the neighborhood of 150-200mg of sodium per 100g. Sodium is reduced, while still imparting the traditional good flavor, color and nutrients.

“California produces significantly lower-sodium sun-dried tomatoes, using sulfur dioxide instead of sodium metabisulfite, for microbial control and to preserve color and flavor in the sun-dried tomatoes,” adds Bewley.

Bewley states other quality factors should be regarded, when sourcing sun-dried tomatoes, including the processor’s HACCP plans, traceability and consideration that safer products may be more expensive. Turkish sun-dried tomatoes may be less expensive, because the labor rate in Turkey is cheaper, but they may not always have sufficient safeguards in place.

Culinary Farms offers California-produced, sun-dried, fresh-dried and organic-dried tomatoes in a variety of cut styles, such as halves, julienned, double julienned, triple diced, coarse diced, small diced and granular, to meet the needs of any application. They also offer roasted tomatoes and Italian-style, sun-dried tomatoes infused with natural herb essences. pf
--Elizabeth Mannie, Contributing Editor

For more information:
Culinary Farms • Woodland, Calif.
Kirk Bewley • 888-383-2767