1Food and Feed Safety Research Unit, Agricultural Research Service, U. S. Department of Agriculture, College Station, TX 77845-4988, USA; vog. adsu@nosredna. nibor (R. C. A. ); vog. adsu@tebsin. divad (D. J. N. )Find articles by.
2Texas A&M University, College of Veterinary Medicine and Biosciences, Department of Veterinary Integrative Biosciences umat. mvc@namroNKFind articles by.
1Food and Feed Safety Research Unit, Agricultural Research Service, U. S. Department of Agriculture, College Station, TX 77845-4988, USA; vog. adsu@nosredna. nibor (R. C. A. ); vog. adsu@tebsin. divad (D. J. N. )Find articles by.
1Food and Feed Safety Research Unit, Agricultural Research Service, U. S. Department of Agriculture, College Station, TX 77845-4988, USA; vog. adsu@nosredna. nibor (R. C. A. ); vog. adsu@tebsin. divad (D. J. N. )Find articles by.
Salmonella-contaminated lymph nodes (LN), when included into edible meat products, are a potential source of Salmonella foodborne disease. In this study, Salmonella was checked in the ventral superficial cervical and mandibular LN from two sow processing plants in the Midwest of the United States. Results indicate that both LN can be contaminated with Salmonella; mandibular LN have higher prevalence (p < 0. 05) of Salmonella than cervical LN (16% vs. 0. 91%), and the majority (>90%) of Salmonella isolates are pan-susceptible or resistant to one antimicrobial, while 9. 78% of isolates were multi-drug-resistant (MDR-resistant to three or more classes of antimicrobials). Taking steps to stop foodborne diseases could include taking these LN out of pork products or only adding them to products that are going to be cooked. Integrated multi-faceted intervention methods need to be developed to reduce Salmonella in the food chain.
Salmonella enterica, which will be called Salmonella from now on, is one of the five most common foodborne pathogens in the world and a major cause of foodborne illness in people [1]. Salmonella is reported to cause over 1. 3 million infections annually in the United States (U. S. ) with approximately 1 million traced back to consumption of contaminated food [2]. Because of these health concerns, the beef, pork, and poultry industries are always looking for ways to make their products less likely to be contaminated with Salmonella. Some people think that adding cattle lymph nodes (LN) to beef ground products could make them more likely to be contaminated with Salmonella [3]. In fact, the peripheral LN of cattle are located in places on their bodies that make it possible for them to be used in beef products. The prevalence of Salmonella-positive subiliac LN in U. S. cattle are reported to be 7. 7% to 62% [4,5,6,7], whereas prevalence of Salmonella in inguinal LN of cattle in Mexico are 54–75% [6,8]. More and more worries are being raised about the fact that 8% to 2020% of Salmonella isolates in those studies were not susceptible to antibiotics [5,7].
If swine LN is found in pork products that people eat, it’s not crazy to think that these products could become contaminated with Salmonella. Salmonella-positive inguinal LN of sows at slaughter are reported to range from 4. 8% to 37% [9,10,11] in the U. S. , whereas popliteal LN in market hogs is reported to be 12. 6% [12]. A study in Mexican slaughterhouses found that Salmonella was common in the subiliac LN beginning in 2010 and continuing through 2020 [13]. There has been limited research on prevalence of Salmonella in swine LN. LN that are positive for salmonella pose a risk of contamination to pork products when they are added to sausage, chorizo, and other pork products [13,14]. The purpose of this preliminary study was to find out if Salmonella was present in the ventral superficial cervical LN and the mandibular LN of sows that were being processed.
Lymph nodes are small, bean-shaped glands that filter lymph fluid and help the immune system. These nodes are present throughout the body, including in pork. Some sausage products contain pork lymph nodes, sparking debate on whether they are truly safe and healthy to eat. Let’s closely examine the facts.
What Are Pork Lymph Nodes?
Lymph nodes are part of the lymphatic system, which supports the body’s immune function. There are hundreds spread throughout the body.
In pigs, lymph nodes can be found along the neck, shoulders, and gastrointestinal tract. They range in size from less than an inch to over 2 inches long.
Pork lymph nodes act as infection fighters filtering bacteria viruses, and other invaders from lymph fluid before it returns to the bloodstream. But does this function make them unsafe for human consumption?
Are Lymph Nodes Commonly Eaten in Pork?
Many parts of pigs consideredwaste products or byproducts often get used as ingredients in sausages and processed pork products. This includes meat from the head, tongue, heart, kidneys, and also lymph nodes.
In particular pork lymph nodes frequently get used in
- Fresh sausages like chorizo and breakfast links
- Cured/smoked sausages like kielbasa and salami
- Lunch meats like bologna or spam
However, the proportion varies widely. Some processed pork contains no lymph nodes, while others may contain up to 10% or more. It comes down to each manufacturer’s recipe.
Do Pork Lymph Nodes Pose Any Health Risks?
The biggest concern around consuming pork lymph nodes is the potential for higher bacteria levels that could cause foodborne illness. However, with proper handling and cooking, the risks appear very low.
Here are some key points on pork lymph node safety:
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Nodes can harbor salmonella at slaughter, but so can other pork parts. Thorough cooking kills any bacteria present.
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No research definitively shows lymph nodes harbor more bacteria than muscle meat. Proper sanitation during processing is most important.
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Nodes make up a very small percentage of any pork product. Even if contamination occurs, it is localized and small in dose.
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USDA regulations require lymph nodes to be as safe as any other pork meat. Manufacturers must adhere to strict cleanliness and testing policies.
So while the idea may seem unappetizing to some, from a scientific standpoint, consuming a small number of pork lymph nodes does not appear notably risky for human health.
Nutritional Profile of Pork Lymph Nodes
Aside from safety concerns, some also question whether lymph nodes offer any nutritional value. Here is how they compare to regular lean pork:
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Protein: Lymph nodes contain slightly less protein than muscle meat, but still provide all essential amino acids. Approximately 15-20g protein per 3 oz.
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Fat: Nodes contain more fat than typical lean cuts, in the range of 5-15g per 3 oz. This adds moisture and flavor.
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Micronutrients: Nodes provide B-vitamins, iron, zinc, selenium. Slightly less than regular pork, but still a meaningful amount.
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Calories: Approximately 130-170 calories per 3 oz, on par with lean pork. The majority of calories come from protein rather than fat.
Overall, while not identical to traditional pork cuts, lymph nodes still supply high-quality protein, fat, and micronutrients. They make an economical, flavor-boosting addition to processed pork items.
Other Parts of the Pig Used Alongside Lymph Nodes
Pork lymph nodes are rarely used completely alone. Sausage containing nodes also commonly includes:
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Heart, tongue, kidneys, stomach – All rich in protein, iron, B12. Also contain more fat than muscle cuts.
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Liver, lungs – Supply vitamin A, folate, copper along with a soft texture. Need proper cooking to avoid vitamin A toxicity.
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Snouts, ears, skin – Mostly collagen for binding and mouthfeel. Also contain small amounts of protein, minerals. Fry to make crispy.
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Intestines – Often used as casing rather than ingredient. Rich in collagen and smooth muscle fiber. Must be thoroughly cleaned.
Like lymph nodes, these parts provide complementary nutrition at a lower cost. Using byproducts reduces waste and supports more sustainable meat production.
Are There Benefits to Eating Lymph Nodes?
Pork lymph nodes have traditionally been viewed as waste. But some emerging research indicates potential benefits to consuming nodes:
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Prebiotic compounds – Nodes contain glycoproteins that may feed beneficial gut bacteria. More research is needed in humans.
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Anti-inflammatory factors – Animal studies show lymph nodes produce substances that may reduce inflammation when consumed.
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Micronutrients – Nodes are rich in zinc, selenium, B vitamins that support immune and metabolic health.
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Electron-dense minerals – High levels of iron, copper, chromium aid energy production and antioxidant activity.
Overall, pork lymph nodes supply a balanced nutritional package that complements other pork cuts used in sausages and processed meats. More benefits may emerge with future study.
How to Tell if a Pork Product Contains Lymph Nodes
Since pork lymph nodes are so small, it can be impossible to detect their presence by looking. Here are some tips:
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Check the ingredient list for clues like “pork glands”, “pork nodes”, or simply “pork”. Non-specific labeling makes nodes likely.
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Look for a coarser, more varied texture than whole muscle products. Small chunks rather than fine, uniform ground may indicate nodes.
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Opt for whole-muscle products like pork chops or roasts. Multi-ingredient processed items are more likely to have nodes.
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Ask the manufacturer if uncertain. Reputable companies should be transparent if nodes are included.
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Make your own sausage at home. This gives full control over ingredients used.
While not a guarantee, these tips can help determine if lymph nodes may be present in any given pork product.
Is Eating Lymph Nodes Safe for People With Allergies or Immune Issues?
For most healthy individuals, pork lymph nodes pose minimal risk and can be part of a nutritious diet. However, those with certain medical conditions may still want to exercise caution:
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People with pork allergies or sensitivities may react to nodes and should avoid completely. Nodes contain many of the same antigens as regular pork.
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Those with compromised immune systems should cook pork thoroughly and limit cured/processed items to reduce infection risks.
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Individuals with lymph node swelling or disorders may choose to avoid nodes, though no direct risks are proven. Consult a doctor for guidance.
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Pregnant women, infants, and young children have greater vulnerability to foodborne pathogens and may wish to avoid.
Talk to your healthcare provider if uncertain about consumption of pork lymph nodes for your individual health situation.
Are Beef and Chicken Lymph Nodes Also Used in Food Products?
Pork is not the only meat containing lymph nodes that get used for human food. Both beef and chicken lymph nodes sometimes find their way into processed and multi-ingredient products.
However, this is far less common than with pork:
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Beef: Lymph nodes in cattle are very small and low yield. Not economical for beef sausage. Mostly used in pet foods.
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Chicken: Some giblet products include chicken lymph nodes. Also occasionally found in canned chicken, luncheon meats.
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Lamb/Goat: Use of lymph nodes is rare, but may be found in some locally made fresh sausages.
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Fish: Fish lymph nodes, also called nuggets, sometimes get included in surimi seafood products like imitation crab.
So while pork leads the way in lymph node consumption, they are not completely exclusive to pork products. As always, check ingredients lists if uncertain or allergic.
Tips for Safely Consuming Pork Lymph Nodes
If choosing to eat pork products containing lymph nodes, you can minimize any risks by:
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Checking ingredients carefully and understanding labeling terms
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Cooking all pork thoroughly to an internal temperature of at least 145°F
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Following good food safety habits like avoiding cross-contamination
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Practicing moderation – nodes make up a small percentage of total intake
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Choosing quality products from reputable producers and retailers
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Consulting a doctor if you have allergies or special health conditions
Overall, pork lymph nodes can absolutely be part of a healthy, balanced diet when safety precautions are followed and intake is reasonable.
While the thought of eating lymph nodes may not appeal to all palates, these small pork glands pose minimal health risks when properly handled. In fact, they provide complementary nutrition to other pork cuts used in sausages and processed meats. Lymph nodes make use of often wasted parts of pigs, thereby reducing waste in meat production. So while consuming lymph nodes may not be for everyone, these small glands can be part of a safe, nutrient-dense, economical diet.
Materials and Methods
Two sow processing plants (Plant A and Plant B) in two separate states in the midwestern U. S. were chosen for sampling. Each plant was sampled on two consecutive days each month for twelve months (November 2016–October 2017). Samples were 25 ventral superficial cervical LN from days 1 and 2 of each month, which were the first Monday and Tuesday for both Plants A and B. That’s 50 samples per month for 12 months, which equals 472 samples for Plant A and 548 samples for Plant B. On the same day every month from February to October 2017, nine months, we also took samples of 150 mandibular LN from Plant A and 217 LN from Plant B (25 LN per day per month per plant x 9 months = 367). We couldn’t get all the samples (both cervical and mandibular) that were planned for the original study design because of bad weather and other sampling problems.
LN Processing, Salmonella Cultivation
LN samples were processed as previously described for meat samples [15]. To prepare the tissues, they were each weighed and recorded, then put into sterile filtered-Stomacher bags (Nasco, Fort Atkinson, WI, USA), mashed with a rubber mallet until flat, mixed with 80 mL of tryptic soy broth (Becton Dickinson, Sparks, MD, USA), and mixed for 30 seconds with a laboratory blender (BagMixer 400VW, Interscience Laboratories Inc.). , Weymouth, MA, USA) at a medium speed (seven paddle strokes per second). The mixed samples were heated at 25 °C for 2 hours and then at 42 °C for 12 hours. They were then kept at 4 °C for no more than 4–6 hours until they were used in another step in the process. For prevalence analysis, 1 mL from each enrichment culture was subjected to anti-Salmonella immunomagnetic separation (IMS). Anti-Salmonella beads (Invitrogen, Carlsbad, CA, USA) were added to 20 µL of each 1 mL aliquot, and the mixture was left to sit at room temperature until it was ready to be used. The beads were extracted from the enriched samples and washed twice in PBS-Tween 20 (Sigma, St. Louis, MO, USA). The beads were put into 3 mL of Rappaport Vassiliadis soya (RVS; Remel Products, Lenexa, KS, USA) broth and left to grow overnight at 42 °C. We found Salmonella in these samples by swabbing the RVS enrichment culture onto brilliant green agar (Becton Dickinson, Sparks, MD, USA) that had sulfadiazine (80 mg/L; Sigma, St. Louis, MO, USA). All plates were incubated at 37 °C for 18 to 20 h. Following the instructions given by the manufacturer (BD Difco, Dickinson and Company, Sparks, MD, USA), up to three possible Salmonella colonies were chosen and confirmed biochemically with lysine iron and triple sugar iron agars.
Pork: Consumer Reports finds harmful bacteria in meat
FAQ
Can you eat pork salivary glands?
Is it safe to eat meat with cysts?
What is the green lump in pork?
Are beef lymph nodes good for you?
Are lymph nodes in sheep meat dangerous?
Although unsightly and unpleasant to find in sheep meat, the cysts are harmless to people. Lymph nodes are grey or light-brown, marble-sized lumps of tissue. They can be found in the fatty areas between muscles, or beside them. Lymph nodes are a natural part of the animal and are not a defect. It’s not common to find lumps or defects in meat.
Why is pork not recommended to eat?
This is not true, some cuts like sirloin and pork rump steak, for example, are very healthy, even healthier than beef and chicken. Only the fattest cuts like bacon and crackling should be avoided.
What foods help lymph nodes?
The powerful enzymes and antioxidants in vitamin C can assist in clearing out toxins and help the lymph nodes combat infection. Citrus fruits that you can consume include lemon and oranges which support detoxification and lymph node function. 6. Turmeric Turmeric is widely known for its blood-thinning properties in the body.
Should you eat cured pork?
Certain cured pork products like bacon contain sulfates or sulfites, chemical preservatives which you should consume in small quantities or avoid altogether. Look for salt-cured or uncured options instead. Keep in mind that the way you prepare pork will impact its fat content. Instead of frying, opt for grilling, roasting, baking, or broiling.