- Hair follicles/bristle remnants
- Usually found in skin-on pork.
- Dark, stiff, and embedded in the outer fat or rind.
- Often look like black dots, short spikes, or coarse hairs.
- Can survive cooking.
- Burnt or oxidized connective tissue
- Occasionally collagen-rich tissue can darken and become surprisingly stiff after long cooking.
- Usually not “wire-like,” though.
- Fragments of bone
- Pork shoulder is often cut through bone.
- Small sharp bone splinters can end up in the meat or fat.
- These are typically pale/white or tan rather than black.
- Actual foreign material
- Rare, but not impossible.
- Processing equipment, brush bristles, or packaging materials can occasionally end up in meat.
- If the objects are uniformly shaped, metallic-looking, or obviously separate from the tissue, don’t assume they’re natural.
A couple of details would help distinguish them:
- Was the shoulder skin-on or skinless?
- How long are the spikes (a few millimeters, 1 cm, several cm)?
- Are they actually attached to the fat tissue, or can they be pulled out like individual strands?
- When you bend one, does it behave like a hair/bristle, a bone fragment, or a metal wire?
- Can you post a photo?
If they’re truly thick black wires sticking out of the fat cap, especially if they’re flexible and rooted in the tissue, bristle remnants are a strong possibility. If they’re rigid, shiny, uniformly manufactured-looking, or not attached to natural tissue structures, I’d stop serving that portion and inspect more closely. A photo would make identification much easier.