## 5 Fermented Products and Quality of the Fat of Broiler Meat
However, the higher proportion of GLA in the feed did not significantly affect the content of other important fatty acids(DGLA, AA) in the breast muscle meat and only slightly higher values were recorded in the thigh muscle meat compared to the control group. It is assumed that the ingested GLA from the feed is directly incorporated into the adipose tissue of the chickens and is not utilized in the formation of other fatty acids (DGLA, AA). A statistically insignificant decrease of DPA, EPA, and DHA in the fat of the breast muscles of the experimental group was observed. On the contrary, in the thigh muscles, the proportion of these acids was slightly higher (\(p>0.05\)). After feeding the FP to the experimental group, there was an increase in the MUFA and PUFA content and, on the contrary, a decrease in SFA in both the meat and body fat of the chickens. The n-6/n-3 PUFA ratio decreased only in the thigh fat; it remained unchanged in the breast muscle fat. In another experiment, the effect of a fermented product at a dose of 5% on the fat quality of broiler chicken meat was investigated [68]. The fermented product was prepared via SSF using the lower filamentous fungus _Cuninghamella echinulata_ and wheat bran was used as a substrate. The experiment also included verification of the effect of feeding the fermented product in a combination with agrimony extract. Agrimony has strong antioxidant effects and also has a beneficial effect on the gastrointestinal tract, which was hypothesized to result in higher oxidative stability of the meat and better growth parameters of the chickens. The fermented product showed a 7.11% GLA content and a higher proportion of ALA and LA compared to the commercial compound feed and a lower proportion of palmitic acid and myristic acid. The prepared fermented product was fed to the chickens from day 17 of fattening at a dose of 5% (the fattening period lasted 38 days). Feeding of the fermented product had a different effect on the fatty acid profile of breast and thigh muscle fat. The most significant was the increase in GLA in both breast and thigh muscle fat. Skimming the FP caused an increase in oleic acid, LA, and DGLA in the fat of the pectoral muscles. Conversely, there was a decrease in the content of the following n-3 PUFA, EPA, DPA, and DHA, compared to the control group. In the thigh fat, a significant decrease in oleic acid and an increase in DGLA, AA, but mainly n-3 PUFA (EPA, DPA, and DHA) compared to the control group was observed. Coinciding with the first experiment, ingestion of the fermented product in combination with budock extract administered in water produced a more pronounced effect on the fatty acid profile. In this experimental group, an overall increase in the saturated fatty acid content (myristic, palmitic) and a decrease in the unsaturated fatty acid content was observed in comparison to the experimental group without rapeseed. In order to obtain meat that may be labelled as a functional food, a higher proportion of essential fatty acids must be achieved. Therefore, it was necessary to prepare a new type of feed and also to increase the ration fed to broiler chickens. To increase the proportion of mainly GLA in the fat of the meat and also to improve the growth parameters of the chickens, a new type of FP containing mainly GLA and beta-carotene was produced. The product was prepared via SSF using the lower filamentous fungus _Umhelopsis isabellina_[56]. _Umhelopsis isabellina_ produce oils rich in PUFA, especially GLA [69]. Com meal was used as a basic substrate, which is a very good source of carbon necessary for fatty acid production. The obtained product contained 3.03 mg g\({}^{-1}\) of GLA and 3.12 ug g\({}^{-1}\) of beta-carotene. However, the proportion of GLA in the fat of the feed was low, only 3.5%. In the final product there was a higher proportion of oleic and linoleic acid, which is related to the composition of the FA of the substrate (maize) in which these two fatty acids predominate.