Finding a lump or defect in meat is a very rare occurrence because of the rigorous meat inspection process, but nevertheless, some get through. Lumps and defects may be found in beef, pork, farmed deer (venison) and sheep meat.
We have comprehensive requirements for carcass inspection to ensure meat sold in New Zealand – whether for local consumption or export – is wholesome and fit for human consumption. By law, inspectors must have been trained and recognised as skilled to do the job. If the inspector is suspicious about any defect found during inspection, they take appropriate action, including rejecting the entire carcass or any part of it.
Lumps and other defects in meat are often either a natural part of the animal (eg, lymph nodes), or are due to healed injuries received when the animal was younger.
Injuries can be caused by:
- deep muscle injections
- ingrown foreign objects (eg, prickles)
- small bacterial infections
- from parasites that lodge in muscles.
The body responds and may surround a foreign object with white blood cells and fluid while trying to destroy it (forming an abscess), or enclose it with hard material (eg, calcium).
Injuries from deep muscle injections are sometimes apparent in the muscles of the neck or occasionally the rump of the animal. Injecting into the rump is however not the preferred practice. Some veterinary medicines and poor injection techniques (eg, dirty needles) may cause tissue irritation, localised infection or scarring. The medicine itself will have been quickly absorbed and metabolised by the animal, although the scar remains. These are known as injection site lesions and in most cases are found during the inspection process. Lumps in the rump muscle are harder to detect when the carcass is whole, but in most cases are found by the butcher when it is cut up for sale.
Lumps in sheep meat are commonly caused by a parasite known as sheep measles (Taenia ovis). The parasite burrows into muscle and goes into a resting stage called a cyst (known as Cysticercus ovis). Cysts appear as hard, white lumps about the size of wheat grains. The sheep’s immune system coats the cyst in calcium and tries to destroy it. Although unsightly and unpleasant to find in sheep meat, the cysts are harmless to people.
Lymph nodes are sometimes mistaken as bad meat but they are a natural part of the animal and are not considered a defect. They show up as a grey/light brown, marble sized lump of tissue in the fatty areas between muscles, or beside them.
All animals grown for meat in New Zealand are inspected by qualified meat inspectors before slaughter. The carcass is again examined during processing, after hide removal, gutting, trimming etc.
The standard of examination MPI requires is amongst the highest in the world. Any affected material is removed before the carcass is classed as fit for human consumption. In the unlikely event that a lump is missed at inspection, it is usually found and removed during the butchering process.
If you are unhappy with a meat product because of its appearance, or presence of a defect, you can take whatever action is appropriate when dealing with unsatisfactory goods. Alternately, you could simply cut out the defect and proceed to cook the meat thoroughly, as normal.
You can also contact a Health Protection Officer at your local District Health Board. Health Protection Officers will work with meat processors and, if necessary, staff in MPI to trace the reasons why the defect was present.