Pickle safety article...acidity reminder

Are Grandmother's Pickle Recipes Safe?

By Sheila Ryan, Colorado State University
Cooperative Extension, El Paso County
April 30, 1999

Coloradans often call Cooperative Extension offices to talk about pickle recipes that have been handed down from one generation to another. The question usually is, "Are these old pickle recipes safe?"

You will find two basic methods of making pickles. In the first method, the vegetables go through a curing process in a salt and water brine solution for one or more weeks. Lactic acid produced during this fermentation process helps preserve the product. The product that results are called brined or fermented pickles. Sauerkraut is made by this method. Once fermentation is complete, these foods must be refrigerated or canned for safekeeping.

It is rare that brined or fermented products are unsafe. You should not eat products, however, that appear spoiled. Toss all products with mold growth, off colors, abnormal odors, slippery surfaces or a mushy texture.

The second method of making pickles is called fresh-pack or quick-process pickles. Here, raw vegetables or fruits are covered with a boiling hot vinegar-water solution, spices and seasonings. In fresh-pack or quick-pickles, the big concern is that sufficient acid be present to prevent growth of harmful pathogens. Cider or white vinegar of 5 percent acidity (50 grain) is recommended for pickling. Bottled lemon juice also can used. Do not use homemade vinegar or vinegar of unknown acidity in pickling. Do not dilute the vinegar unless the recipe specifies this. If a less sour product is preferred, add sugar rather than decrease the vinegar.

Often old pickle recipes will call for less vinegar than water. This is a potential safety problem because enough acid must be present to prevent growth of dangerous pathogens. Recently a Consumer asked if her quick dill pickle recipe passed down from her mother was safe. It called for two cups water for every cup of vinegar.

In the past, vinegar was sold as seven percent acetic acid. Commercial vinegar is now 5 percent acetic acid. Old recipes developed for stronger vinegar might not contain sufficient acid to be used with today's 5 percent vinegar.

In this case, if the Consumer makes her mother's recipe as is, it must be stored in the refrigerator for safety. For room temperature storage, the amount of vinegar must be increased so at least as much vinegar as water (1 part vinegar to 1 part water) is used. In addition, the pickles must be processed in a boiling water canner.

Safe pickle recipes are those tested and published by USDA. They are available through land grant universities, such as Colorado State University Cooperative Extension. Also those recipes having at least one part vinegar to one part water ratio are safe.

Often I hear the question "For generations my family has made top quality pickles without using a boiling water process to can them. Why have recommendations changed?

Pasteurization in a boiling-water process destroys yeasts, molds and bacteria that may cause the product to spoil. The water bath process also inactivates enzymes that could affect the color, flavor and texture of the pickle or relish. In addition, a strong vacuum seal is formed so that pickles won't mold.

Mold growth in canned pickles indicates underprocessing and the pickles should be discarded. The mold contains harmful mycotoxins and may reduce the acid content of the pickles. If the acid content is sufficiently low, Clostridium botulinum spores, if present, could grow and produce botulism.

Why are grape leaves called for in some old fashioned recipes? Grape leaves contain tannins that inhibit enzymes which make pickles soft. They are safe to use. If, however, good quality ingredients are used and up to date methods are followed, crisping agents such as alum, pickling lime and grape leaves are unnecessary. To produce a crisp pickle, use vegetables within 24 hours of harvest. Pick cucumbers early in the morning and keep in a cool place as they deteriorate rapidly at room temperature.