Jerky

Jerky is meat that is cut into long, thin strips and dried. Jerky was a popular snack with early trappers and soldiers because it kept well, was light and easy to carry. For the same reasons it is a popular food with today’s hikers and is always on top of the list of the survival items. Jerky can be made from any lean meat such as beef, pork, poultry, fish or wild game. There is an unlimited number of flavors that may be created, for example smoky or not, hot and spicy, barbecue, Italian sweet and hot, and others. Best jerky is made from lean meat as fats become rancid in time, spoiling the flavor. Venison being very lean by nature, is great for making jerky.

Safety Concerns. Food Safety Regulations for Shelf Stability require jerky to lose moisture until its water activity (Aw) level is:

USDA guidelines state that: “A potentially hazardous food does not include a food with a water activity value of 0.85 or less.” Although jerky is perfectly safe at Aw 0.85, nevertheless molds can still develop on its surface when the air will develop higher humidity. At Aw 0.70 the molds will not grow. Traditionally, jerky was only dried.

In October 2003, in New Mexico, there was an outbreak of Salmonella that was traced to jerky production in one of the small plants. In response to this outbreak, the Food Safety and Inspection Service has initiated a series of policy changes and guidelines. Jerky is usually made from beef and the cooking guidelines for beef products should be observed. What FSIS has concluded is that it is not enough to follow the time-temperature guidelines, but to also include the humidity factor in the cooking process. To make it short: it is necessary to maintain the relative humidity of the oven at 90% or above for at least 25% of the cooking time and no less than one hour. This ruling has started a heated and ongoing debate between FSIS and small jerky manufacturers who claim that maintaining such high humidity in a smokehouse is difficult and may force them out of business. Another argument is that the humidity requirement changes the quality of jerky. Due to today’s microbiological concerns, particularly E.coli 0157:H7, Salmonella, and Listeria monocytogenes jerky must be exposed to thermal processing. A hobbyist is not bound by those rules but we believe it is beneficial to know about the latest safety requirements for making jerky products. The United States Department of Agriculture has divided jerky into specific categories:

  1. Jerky - The product is produced from a single piece of meat. The product can also be labeled as “Natural Style Jerky” provided that the product name is accompanied by the explanatory statement “made from solid pieces of meat.”
  2. Jerky Chunked and Formed - The product is produced from chunks which are molded and formed and cut into strips.
  3. Jerky Ground and Formed or Chopped and Formed. The meat is ground, molded, pressed and cut into strips.

Safety of Home Made Jerky

It must be noted that pork and wild game (bear, venison) meat is at risk of being infested with trichinae and should be either cooked or accordingly treated. Commercially made jerky is monitored by inspectors of the U.S. Department of Agriculture’s Food Safety and Inspection Service. Home made jerky, often made from venison, is often made in a hazardous way. Dried meat will keep for many years if kept at low humidity because bacteria will not grow under such conditions. That does not mean that all bacteria are dead. E.coli was found in dried but uncooked jerky that has been stored at room temperature for more than a year. Although curing salt (Cure#1) is not required in the manufacture of homemade jerky, it is recommended that it be used. Curing salt offers many advantages:

Reprinted from FSIS - Food Safety of Jerky:

Why is Temperature Important When Making Jerky?

Illnesses due to Salmonella and E.coli 0157:H7 from home made jerky raise questions about the traditional drying methods for making beef and venison jerky. The USDA current recommendation for making jerky safely is to heat meat to 160° F (72° C) before the dehydrating process. This step assures that any bacteria present will be destroyed by wet heat. Most dehydrator instructions do not include this step, and a dehydrator may not reach temperatures high enough to heat meat to 160° F. After heating to 160° F, maintaining a constant dehydrator temperature of 130 to 140° F (54 - 60° C) during the drying process is important because: the process must be enough to dry food before it spoils; and it must remove enough water that microorganisms are unable to grow.

Why is it a Food Safety Concern to Dry Meat Without First Heating it to 160° F?

The danger in dehydrating meat and poultry without cooking it to a safe temperature first is that the appliance will not heat the meat to 160° F - a temperature at which bacteria are destroyed - before it dries. After drying, bacteria become much more heat resistant. Within a dehydrator or low-temperature oven, evaporating moisture absorbs most of the heat. Thus, the meat itself does not begin to rise in temperature until most of the moisture has evaporated. Therefore, when the dried meat temperature finally begins to rise, the bacteria have become more heat resistant and are more likely to survive. If these bacteria are pathogenic, they can cause food borne illness to those consuming the jerky.

Recent work at the University of Wisconsin has demonstrated that the following temperatures are effective at killing E.coli 0157:H7 in jerky products. It is recommended that dehydrator temperature of 145º F (63º C) or higher be used.

Drying Temperature Minimum drying time
125º F (52º C) 10 hours
135º F (57º C) 8 hours
145º F (63º C) 7 hours
155º F (68º C) 4 hours

Making jerky from a single piece of meat

Making safe jerky requires cooking the meat before placing it in the dehydrator or oven. The USDA recommends that meat be heated to 160° F (72° C) before dehydrating.

  1. The leaner the meat, the better the jerky. Either fresh or frozen meat can be used. Meat should be trimmed of fat and connective tissue.
  2. Slice partially frozen meat into 1/4” strips, 6” long x 1” wide.
  3. Marinating. Home produced jerky made of sliced meat pieces is usually marinated overnight and 8 hours is plenty. About 1/2 cup (120 ml) of marinade for each pound of meat sounds right. Drain the slices and pat them dry with paper towels. Sprinkle with black pepper and other spices you like.

    Basic jerky marinade:

    1 cup soy sauce
    1/4 cup Worcestershire sauce
    1 Tbs. powdered garlic
    1 Tbs. black pepper
    1 Tbs. liquid smoke

    This amount of marinade is enough for 5-7 lb. of meat.
    Commercially made jerky will not be marinated but mixed with salt, nitrite and spices in a tumbler. Then it will be dried.

  4. Cook meat according to 160º F (72º C) as recommended by FSIS. You could bring the marinade with strips of jerky to a boil, but you may not have enough marinade. More water can be added into your marinade. Another fine solution is to make a special brine just for that purpose.
    Bring half of the brine to a boil. Insert meat pieces, bring brine to a boil and cook for 2 minutes. Remove strips and let them dry. Change brine for the second half of meat and repeat the process.
  5. Begin dehydrating immediately after cooking. Dry at 130-140° F (54-60° C) until a test strip cracks but does not break when it is bent.
    Jerky can be dried in the sun, oven, smokehouse or dehydrator.
  6. Apply smoke if smoky flavor is desired. There is a danger when smoking very thin meat strips with heavy smoke for too long. If smoked longer than 60 minutes they might develop an unpleasant bitter flavor. Keep in mind that sausage meat is encased with casings which acts as a barrier to smoke penetration. The casings contain millions of tiny holes which let the smoke in. Thin jerky cuts have no protective barrier and accept smoke rapidly. If smoking temperature is maintained between 130-140° F (54-60° C), there is no difference between smoking and drying and it might be considered one process.
  7. Let it cool and then place in a plastic bag. Remove air and seal tightly.

A typical jerky brine

Brine 21° SAL USA Metric
Water 1 gallon 3.8 liters
Salt 3/4 cup 220 g
Powdered garlic 1 Tbs 8.5 g
Powdered onion 1 Tbs 7.5 g
Sugar 1 Tbs 15 g
Liquid smoke 1/2 tsp 2.5 ml
Note: Liquid smoke is not needed when natural smoke is provided. This amount of brine is sufficient for 5 lb of meat.

Liquid smoke. The use of liquid smoke is beneficial when food dehydrators are used since the smoking process can not be performed inside of the unit. In these cases liquid smoke which comes in a variety of flavors can be added to marinade. Liquid smoke is very strong so be careful as more is not necessarily better.

Restructured Jerky

(made from ground meat)

Making ground meat jerky resembles making sausage.

  1. Grind lean meat through 1/4” (6 mm) plate.
  2. Add all ingredients to meat and mix together. Adding Cure #1 is a good idea, as it inhibits the growth of pathogenic bacteria. You want the sausage mass to feel sticky, exactly like during making sausages. You may add some water to facilitate mixing and spice distribution. Leave the sausage mass overnight in a refrigerator. Cover the meat.
  3. Stuff meat into flat strips using grinder attachments for making jerky or jerky gun. Use a plastic mat that prevents jerky from being easily removed.
  4. Preheat oven to 325° F (162° C). Boiling it might break it apart and cooking in a oven or in a smokehouse is the preferred method.
  5. Place the ground meat strips on a cookie sheet.
  6. Heat to 160° F (72° C) internal meat temperature.
  7. Begin dehydrating immediately after cooking. Dry at 130-140° F (54-60° C). Place the strips close together, but not touching. Jerky is done when a test strip cracks but does not break when it is bent. That should take about 8-10 hours.
  8. Apply smoke if smoky flavor is desired. If smoking temperature is maintained between 130-140° F (54-60° C), there is no difference between smoking and drying, and it might be considered one process.
  9. Let cool and then place in a plastic bag. Remove air and seal tightly.

Jerky made from wild game

Pre-cook wild game to 165° F (74° C). Game meats are often infected with trichinae and other parasites. If the meat will not be cooked, it should be frozen according to the USDA rules. Freezing meat takes care of trichinae but will not eliminate bacteria from the meat. The majority of recipes on the Internet do not mention the fact that jerky should be pre-cooked in order to be microbiologically safe. Some of us will refuse to accept this fact and will not cook jerky. Well, there are extra precautions that might be implemented to increase the safety of the product:

People who like to decrease the amount of salt or use salt substitutes should pre-cook jerky.

Useful Information

Procedures for making jerky outlined in this chapter are presented with safety in mind and they are based on the latest USDA requirements. Many people will continue making jerky without precooking meat, the way they have always done it. Whether you would follow them or make jerky in accordance with the USDA regulations is up to you although we strongly believe that safety is the most important step of any meat processing operation.