Feeding Acorns to Pigs – Jamon iberico

Jamon iberico is a type of cured leg of pork that comes from black Iberian pigs. It is considered some of the highest quality pork because of the rules and regulations for how the pigs are raised and fed. It is a staple in Portuguese and Spanish diets. These pigs are free-range because they graze in oak groves where they feed on natural surroundings such as roots, chestnuts, herbs, grass, and acorns. Once the time of slaughter nears, their diet becomes stricter.  They’re only allowed to consume chestnuts and acorns because pigs that consume these nuts provide the best quality ham.

So, what is it about acorns that makes them such a good option for providing high quality nutrition to these pigs? Many studies have been done to look at the effects acorns have on the quality of pork. According to the National Institutes of Health, “It could be summarized that acorn intake enhances the fat content and the fatty acid profile, which acts as a carrier for the flavor and, indirectly, juiciness”.

Acorns are plentiful in the fall months, and are high in fat, and many other vitamins and minerals such as Vitamin A and manganese. In the aforementioned article, the NIH explains, “Acorns are considered the most important feed ingredient for several native pig breeds (such as Alentejana, Bisaro, or Iberian) raised under extensively traditional conditions”. Since acorns are high in healthy fat and tannins, they help prevent something called lipid peroxidation, which is when free radicals interact with lipids and cause degradation. While the tannins contained in acorns can be toxic to humans and other animals, pigs can digest them just fine.

The fatty acid profile of the pigs eating an acorn rich diet was a significant factor in these studies. These fatty acids include saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), and polyunsaturated fatty acids (PUFA). “For years meat intake has been linked with adverse health problems, due to the content of SFA, which has been associated with an increased prevalence of cardiovascular disease and various medical disorders.” As a result of this, the pork industry has investigated improving the fatty acid profile of pigs.

According to current health recommendations, “the diet should be rich in PUFA and MUFA and low in SFA due to the apparent relationship between plasma cholesterol and cardiovascular disease”. The fatty acid profiles of commercial pigs were compared with those on the stricter diets which include acorns. The results showed “an increase in MUFA content (specially C18:1), a decrease in SFA content, and no difference in the content of PUFAs when Iberian “Montanera” was compared with Cebo Iberian pigs (concentrate-based diet).”

The rearing system used for these pigs is called montanera in which “acorns are used to fatten the pigs to provide the pig’s muscle and adipose tissues with typical chemical characteristics”. This system seems to be a success for those trying to raise the healthiest quality of ham for consumers.

Sources:

Jamón ibérico – Wikipedia

The Quality and Health-Promoting Value of Meat from Pigs of the Native Breed as the Effect of Extensive Feeding with Acorns – PubMed (nih.gov)

Improving Fatty Acid Profile in Native Breed Pigs Using Dietary Strategies: A Review – PMC (nih.gov)