Pickled to Perfection

  While not all pickled products undergo fermentation, in many vegetables the natural sugar is converted to lactic acid by specific bacteria during fermentation. This process turns cabbage into sauerkraut and cucumbers into pickles.

  Some general principles apply to all types of pickled vegetable products. Factors such as post-harvest handling, quality of ingredients, and proper processing techniques greatly influence the quality of finished pickled products.

  The various species of lactic acid bacteria responsible for vegetable fermentation have their own levels of salt tolerance and temperature ranges for growth. Strains of Leuconostoc mesenteroides (of the Streptococceae family) initiate vegetable fermentations, followed by other species of lactic acid bacteria (Lactobacillus). The Leuconostoc are salt- and sugar-tolerant over a wide range of temperatures and are able to initiate vegetable fermentations more rapidly than other bacteria.

  Carbohydrates in the vegetables furnish energy for the bacteria in the form of sugars and other essential nutrients: amino acids and peptones, lipids, vitamins and minerals. The bacteria ferment sugar to lactic acid, as well as carbon dioxide, ethyl alcohol, and acetic acid. These products of fermentation rapidly lower the pH, inhibit the growth of undesirable microorganisms, and deactivate vegetable-softening enzymes.

  Two general methods of packing are used for ideal fermentation conditions: dry-salting and brine-salting. Usually, shredded or chopped cabbage is dry-salted in the production of sauerkraut. Vegetables such as cucumbers, olives and large vegetable pieces normally use brine.

  Basic brines are solutions of salt and water. They may include sugars, flavorings and other ingredients. Salinity is measured with a brine hydrometer, called a "salometer." This instrument has a scale from 0 to 100 degrees. It is calibrated in percentages of saturation with respect to sodium chloride. A saturated solution of sodium chloride, 26.5% salt, reads 100 degrees Salometer.

  In brined vegetables, undesirable aerobic microorganisms are inhibited by the production of carbon dioxide and acid. Carbon dioxide replaces air, creating anaerobic conditions favorable to ascorbic acid stabilization and oxidation inhibition.

  Brine or salt draws water from vegetables, decreasing the salt concentration in the brine itself. During the pickling process, brine strength is usually raised gradually; otherwise, acid development would be inhibited and the vegetables would become soft. All production facilities recirculate brine to reduce pollution and conserve resources.

  As the salt concentration increases, less acid is produced due to inhibition of lactic acid bacteria. The vegetable's sugar content is directly related to the amount of acid that is produced, so the higher the sugar level, the less salt that is needed. For example, because the amount of fermentable sugars in cabbages is higher than that of cucumbers, less salt is used in sauerkraut production than in pickle processing, and more acid is produced in kraut than in pickles.

  "Salt is salt when it comes to pickling," says Skip Niman, director of quality administration, Cargill Salt Division, Minneapolis. "Any of the three types of salt may be used in making brines: solar, rock or evaporated. Most people tend to use solar because it's less expensive than evaporated salt."

  The salt used in brine production should be free of flow agents and iodine to avoid producing a cloudy brine and darkened pickles. (For more specifics on the types of salt available, refer to "The Many Benefits of Salt" in the October 1994 issue of Food Product Design.)

  Pickled and fermented vegetable products may be classified into four general categories based on the process used to create them: 1) unfermented products, such as California-style black and green olives; 2) weak brine fermented products, such as dill pickles; 3) high-salt brine products, such as salt-stock pickles; and 4) dry-salted products, such as sauerkraut.

  Commercially, olives are usually treated with a dilute solution of sodium hydroxide (lye) to remove the bitterness caused by the glucoside oleuropein. The olives are held in large tanks in dilute brine until further processing. The holding tanks are outdoors, where the UV radiation from the sun prevents the growth of unwanted microorganisms.

  Processing conditions differ according to the olive variety and the processor. The brine strength starts out low and is gradually increased to about 7% to 9% salt, which is maintained for several months. Eventually, the brine is kept at 40 degrees Salometer (10% salt).

  As with all pickling industries, olive processors must arrange for environmentally sound waste brine disposal without soil or water contamination. Olive processors can now hold olives in salt-free brines by using an acidic solution of lactic acid, acetic acid, sodium benzoate, and potassium sorbate. The flavor of the olives in salt-free storage is reportedly good or better than conventional salt-brine storage. Other salts such as ammonium nitrate also have been examined for olive storage.

• Black ripe olives. California-style black ripe olives are made from either fresh or brine-stored olives. The pickling process involves several lye treatments followed by aeration to darken the skin. The color is improved by increasing the number of lye applications and shortening the length of each treatment. Finally, the olives are rinsed with water and stabilized in a weak brine for several days before canning.

• Green olives. California-style green olives are produced from ripe varieties that are picked at a pink or straw-yellow stage. They are treated with lye, which penetrates through to the pits. After washing -- with as little exposure to air as possible to avoid darkening -- the olives are processed in dilute brine and canned similarly to black ripe olives. Depending on the temperature, lactic acid fermentation may take as long as 6 to 10 months. The salt concentration in the brine is considerably higher for green olives than for black olives, although the exact concentration depends on the variety.

    Spanish-style pickled green olives are processed similarly to California-style olives, except they are picked while they are still green. The lye does not penetrate through to the pits, leaving some untreated bitter flesh which is characteristic of this type.

• Greek-style olives. Olives for Greek-style olive production are picked when they ripen naturally to purple or black. These fermented products may be treated with brine or dry-salted, but they are not treated with lye. The curing process may take 6 to 9 months. Their flavor profile is entirely different from lye-cured olives.

  Dill pickles are the most popular type of pickle, followed by bread-and-butter pickles, sweet pickles, and garlic pickles, according to Richard Hentschel, executive vice president of PPI. The popularity of dill pickles is attributed to their use on hamburgers and other sandwiches.

  "Kids get accustomed to dill-flavored pickles on hamburgers, and that follows them into adulthood," says Hentschel.

  Most manufacturers have their own pickle formulas, developed over the years and sometimes handed down through generations of families. Cucumbers of old were salted and fermented in wooden barrels or tanks. Today's pickle packers may produce a variety of fermented or unfermented products that are stored in fiberglass, plastic or rubber.

  Most cucumber pickles are made by one of three methods: processed, fresh-pack or refrigerated. These methods allow the pickles to take on distinctive flavors and textures. Various herbs, spices and flavorings may be added to the pickling liquid to create many unique types of pickles. Most pickles are pasteurized; however, refrigerated pickles are not.

• Processed. These types of pickles are also known as "cured" or "fermented." After washing, cucumbers are placed in a salt brine and are fermented in large tanks for 1 to 3 months. During this time, salt is added gradually to the tanks. The pickles are then desalted and put into jars with the appropriate seasonings. Processed pickles have a sharp flavor and are marked by a somewhat translucent, dark green appearance.

• Fresh-pack. Fresh, clean cucumbers are placed directly into jars and are covered with a pickling solution of vinegar and seasonings. After the containers are vacuum-sealed, they are quickly pasteurized and cooled. Fresh-pack pickles are never held in tanks. They are generally crisper and less acidic than processed pickles.

• Refrigerated. These pickles undergo the same steps as fresh-pack pickles, but they are not pasteurized. Sodium benzoate may be added to extend shelf life. After the cucumbers are put into jars, they are immediately stored under refrigeration, where the entire fermentation process takes place. The pickles are then shipped to stores, where they are sold in the refrigerated section.

  The salt-stock pickles are kept in large holding tanks outside in a stockyard, so the salt concentration must be high enough to prevent freezing in winter. It may vary from 8% to 12% salt, or higher. The pickles may be held this way for a year or more before they are further processed into finished pickles. Then they are refreshed in several changes of water to reduce the salt content to about 4%.

  Researchers at the U.S. Food Fermentation Laboratory in Raleigh, NC, have been working on a system to reduce or eliminate the amount of salt required for long-term bulk cucumber storage, for environmental reasons. Roger McFeeters, Ph.D., presented his recent findings at the American Chemical Society's annual meeting in Orlando last month. Exact details were unavailable at the time this issue went to press.

  The fermentation to produce dills differs from that used to make salt-stock pickles. Usually a low-salt brine of 5% salt or less is used, and the brine is normally acidified with vinegar. During the curing process, the cucumbers are transformed from white and opaque to darker green and transparent.

  Overnight dill pickles involve a slow acid fermentation at low temperatures in a weak brine for only a day or two. They taste more like fresh cucumbers. Because overnight dills have less salt and acid, their shelf life is shorter.

  Genuine dill pickles are a result of the natural fermentation of fresh cucumbers in a salt brine containing dill, vinegar and a mixture of spices. It may take from 4 to 8 weeks to ferment, cure and absorb the flavor. Genuine dills must be covered with the "genuine" brine from the original fermentation process. This brine is usually cloudy from fermentation byproducts; however, these may be removed by filtration.

  While the brine of genuine dill pickles often contains around 10% salt, the brine of Polish or Hungarian dill pickles is half that strength. Therefore, they are considered partially fermented.

  Imitation dill pickles, or "processed dills," are produced from salt-stock pickles. The cloudy brine is replaced with fresh, clear brine containing low levels of salt, vinegar and dill.

  Kosher dills have a more robust flavor than regular dill pickles due to the addition of garlic and other spices to the brine.

  Sour pickles and half-sour pickles are "soured" or covered with distilled vinegar after desalting. Length of time in the brine determines the degree of sourness.

  Sweet pickles are made from either fresh cucumbers or, more likely, salt-stock pickles. After refreshing the salt-stock, the pickles are covered in a hot solution of sugar, spice and vinegar. Mechanical piercing of the pickles facilitates syrup penetration.

  Tight packing of the cabbage and proper covering of the tanks are necessary for anaerobic lactic acid fermentation. The acid content of the finished product should be approximately 1.5% to 2.0% in order to develop the characteristic flavor and prevent microbial spoilage. Yeast contamination is responsible for pink-colored kraut.

  Southerners prefer relish and salad cubes (a type of relish with larger pieces than regular relish), as well as pickled watermelon rinds. More peppers are consumed out West, according to Jackie Burchfield, marketing manager for Vlasic, Camden, NJ.

  Refrigerated pickles are preferred more in the Northeastern region and in large urban areas. Sweet pickles are big in the Northeast, and bread-and-butter pickles are popular in the Central region. Dill pickles are the only pickle with universal appeal.

  "Consumers are looking for foods that are spicier and have a little heat to them even in the pickle area," says Hentschel. "Southwestern tastes have also influenced this industry."

  Vlasic has just launched a Cajun-flavored pickle in its new Snack MMs line. "This is a hot and spicy product that contains red pepper and other spices. It's a small, bite-sized, fresh, crunchy pickle just for snacking," says Burchfield.

  Pickled peppers are in keeping with the demand for more highly flavored hot foods. They are made the same way as cucumber pickles. The many varieties of pickled peppers include banana peppers, jalapeño peppers, cherry peppers, and pepperoncini.

  New pickle products have been created by experimenting with both the ingredients and the processes. The most recent innovation has been the introduction of sandwich sliced pickles. These are processed the same way as traditional pickles, except they are sliced lengthwise, either smooth or crinkle-cut.

  "They lie flat on the sandwich. Typically two or three of them build a sandwich, so you get a pickle in every bite," says Hentschel. "This product has helped build the pickle category in the last 18 to 24 months, in addition to boosting pickle awareness."

• Tangy lemons. Preserved lemons in the Bella Cucina line from Bellissima! Inc., Atlanta, are a blend of lemons, lemon leaves and Kalamata olives packed in salt brine. Jill Sheehan of Bellissima! says these are a Mediterranean condiment, originally from Morocco. "After you scoop out the lemon pulp, the sweet, tangy rind is used to enhance stews, roast chicken, pasta, pesto and other dishes," she says.

• Various veggies. Picklers such as Michael Cain, president and founder of OH'Brine's Pickling Inc., Spokane, WA, prefer to process vegetables other than cucumbers. Cain says his customers asked for a wider offering of pickled products such as garlic, carrots and asparagus. The company produces a line of gourmet green olives in four varieties, including garlic and jalapeño, as well as a line of rehydrated sun-dried tomatoes packed in a flavorful brine with Italian-style spices.

• Sweet stuff. Sechler's Fine Pickles in St. Joe, IN, has found a niche with its line of gourmet candied sweet pickles. Flavors include orange, lemon and raisin, as well as the newest flavor: candied apple cinnamon. The company also has tried various berry-flavored pickles and is experimenting with other unique pickle flavors, according to David Sechler, president. These candied pickles go through a double sweetening process, where sugar is added in two stages.

• Good-bye salt and vinegar. While vinegar and salt are traditional ingredients for pickle processing, some packers have eliminated them from their products due to consumer demand. Some vinegar-free, no-salt pickle products in the Pickle Eater's line from New Morning in Acton, MA, contain only cucumbers, honey, lemon juice concentrate, water, spices and turmeric. Special processing considerations involve smaller batch sizes and controlling the acidity with lemon juice, according to Gene Fialkoff, president. Although the products are not pasteurized, they are heat-sealed, resulting in a shelf life of two years.

• Orange cukes and purple carrots. Cucumbers are regarded for their flavor and texture, but their nutritional value is not significant. High-carotene cucumbers have been developed by the research team of Philipp W. Simon, Ph.D., and former graduate student John P. Navazio at the Agricultural Research Service's Vegetable Crops Research Laboratory in Madison, WI.

  There are 36 basic types of pickles, according to PPI. These examples help illustrate the many possibilities for pickling. What more could a product designer ask for? A jug of brine, a loaf of bread, and pickles beside me...

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