# Selenium Content of Goose Breast Meat Depending on the Type of Heat Processing
## 3 Results and Discussion
### Selenium Content and Retention  
Geese take up selenium with conventional feed in organic (SeMet and Se-Cys) or inorganic (sodium selenite) form. In regions of the world where this element is found to be deficient in the environment, geese can take it up from feed fortified with Se-enriched yeast, selenium chelate, nano-Se, or algae such as _Scenedesmus quadricauda_ and Chlorella. Drinking water is also a source of selenium in goose nutrition. Although the Se content in water is minimal (10-20 \(\mathrm{\SIUnitSymbolMicro g}/\mathrm{L}\)), there are regions of the world where the content of this element in water is high, including areas of the US, Venezuela and China [37; 38]. Skeletal muscle is reported to be the major Se body pool, accounting for approximately half of the total body Se. Goose meat contains selenoproteins, of which the main biologically active form of selenium is the amino acid selenocysteine (SeC), 81% of which is absorbed mainly in the small intestine [36; 39]. During heat treatment, culinary losses caused by mass transfer are influenced by both cooking conditions--such as the method, surface, temperature, and time--and the properties of the meat, including its moisture, fat and protein content, pH value, and size. Several research papers [8; 23; 33; 34; 40] have been devoted to the effect of heat treatment on the content of minerals (Ca, K, Mg, Na, Fe, Cu, Zn, Mn, P, B, Al) in goose meat, but they did not address selenium. Therefore, this study is the pioneering effort to identify the presence of selenium in goose breast meat, both with and without skin, following exposure to different culinary techniques. In our study, muscle type (with or without skin) had no significant effect on the selenium content of White Koluda goose breast muscles. However, a significant (\(p\leq 0.01\)) effect of heat processing on the value of this element in muscles was observed. Raw muscles (15.3 \(\mathrm{\SIUnitSymbolMicro g}/\mathrm{100}\) g Fresh Mass) had the lowest selenium content, compared to heat-treated ones: R\(<\) OCR, G, PF, WBC (25.8; 25.6; 24.3; 21.8 \(\mathrm{\SIUnitSymbolMicro g}/\mathrm{100}\) g FM respectively). The Se content found in raw breast muscles was higher than that determined by [PERSON] et al. [37], [PERSON] et al. [38], [PERSON] et al. [39] and [PERSON] et al. [41] (14; 0.035; 13.1; 9.25 \(\mathrm{\SIUnitSymbolMicro g}/\mathrm{100}\) g, respectively). The differences in the values obtained are due to the origin of goose meat (commercial sales, experimental studies), different breeds (White Koluda, Canada goose, Gray, Gorki breed), sex and diet. There was also a significant (\(p\leq 0.01\)) interaction between the type of muscle (with or without skin) and the heat processing used. Significantly, the highest selenium content was found in OCR-treated skinless muscle (26.7 \(\mathrm{\SIUnitSymbolMicro g}/\mathrm{100}\) g) compared to raw muscle (17.4 \(\mathrm{\SIUnitSymbolMicro g}/\mathrm{100}\) g). Grilling and pan-frying also significantly (\(p\leq 0.05\)) increased the selenium content in skinless muscles, compared to raw muscles (24.9 and 24.3 vs. 17.4 \(\mathrm{\SIUnitSymbolMicro g}/\mathrm{100}\) g). In the case of muscle with skin, all the thermal treatments applied significantly (\(p\leq 0.01\)) increased the selenium concentration, compared to raw muscle: OCR, G, PF, WBC \(>\) R.  
The higher Se content of roasted meat is due to its retention, which occurs when high temperatures act on muscle proteins. During roasting, when the temperature is between 100 and 140 \(\mathrm{\SIUnitSymbolC}/\mathrm{proteins}\)' digestibility is reduced by forming intramolecular and intermolecular covalent bonds [42]. In another study, it was shown [28] that a crust is formed during roasting of goose meat, which prevents the escape of water and thus minerals, which explains their higher concentration in cooked muscles.