Effect of thermal processes on changes in basic chemical composition of wheat grain

Celem pracy było określenie zmian składu chemicznego ziarna pszenicy odmian: ‘Finezja’, ‘Retro’ i ‘Nikol’ zachodzących pod wpływem ekstruzji i naświetlania promieniami podczerwonymi. Ziarno nawilżano do 15 i 25 % wilgotności i ekstrudowano w temp. 110/135/175/180/124 ºC oraz naświetlano promieniami podczerwonymi w 100 i 130 ºC przez 30 i 90 s. W materiale doświadczalnym oznaczono zawartość: suchej masy, popiołu surowego, tłuszczu surowego, białka ogólnego, włókna surowego, BAW, frakcji włókna (ADF, NDF, CEL, HCEL i ADL) oraz skrobi. W ziarnie pszenicy naświetlanej w temp. 130 ºC przez 90 s stwierdzono istotne zmniejszenie (p ≤ 0,05) zawartości białka ogólnego (o 7 % w ziarnie ‘Finezja’ i o 5 % w ziarnie ‘Retro’) oraz tłuszczu surowego (o 4 % w odmianie ‘Finezja’). W analizowanym materiale procesy termiczne spowodowały zmniejszenie zawartości włókna surowego, najwięcej w ekstrudowanym ziarnie ‘Finezja’, ‘Retro’ i ‘Nikol’, odpowiednio o: 38, 26 i 39 %. Zmniejszeniu uległa także zawartość skrobi w ekstrudowanym i w naświetlanym ziarnie ‘Finezja’ (odpowiednio o: 18,5 i 10 %). Zjawisko to obserwowano również w przypadku frakcji włókna pokarmowego. Największe ubytki dotyczyły: ADF (24 % – ‘Nikol’), NDF (12 % – ‘Retro’ i 9 % – ‘Nikol’), CEL (17 % – ‘Nikol’) oraz HCEL (16 % – ‘Retro’ i 10 % – ‘Nikol’). Niekorzystnym efektem zastosowanych procesów był wzrost zawartości ADL (o 7 % w naświetlanym ziarnie pszenicy ‘Finezja’ i o 11 % – w ekstrudowanym ziarnie ‘Retro’). Najlepszą modyfikację składu chemicznego ziarna w wyniku ekstruzji uzyskano w pszenicy ‘Finezja’ i ‘Nikol’, nawilżanej przed procesem do 25 % wilgotności, a w efekcie naświetlania – w odmianie ‘Nikol’.The objective of the research study was to determine the changes in the chemical composition of grains of the ‘Finezja’, ‘Retr’ and ‘Nikol’ wheat cultivars resulting from the processes of extrusion and infrared radiation. The grains were moisturized to obtain 15 and 15 % of moisture therein and extruded at a temperature of 110/135/175/180/124 ℃ as well as irradiated by infrared radiation at 100 and 130 ℃ for 30 and 90 s. In the material analyzed, the following was determined: dry matter, crude ash, ether extract (crude fat), total protein, crude fibre, NFE, fibre fractions (ADF, NDF, CEL, HCEL and ADL), and starch. In the wheat grains irradiated at a temperature of 130 ℃ for 90, a significant (p ≤ 0.05) decrease in the content of crude protein was reported (about 7 % in the ‘Finezja’ grains and 5 % in the ‘Retro’ grains) and in the content of crude fat (4 % in the ‘Finezja’ grains). In the analyzed material, the thermal processes performed caused the content of crude fibre to decrease (the highest decrease was in the extruded ‘Finezja’, ‘Retro’, and ‘Niko’ grains, respectively: 38, 26, and 39 %). Additionally, the content of starch decreased in the extruded and irradiated ‘Finezja’ grains (respectively: 18.5 % and 10 %). The same phenomenon was also found in the case of dietary fibre fraction. The highest losses referred to the following: ADF (24 % - ‘Nikol’); NDF (12 % - ‘Retro’ and 9 % - ‘Nikol’); CEL (17 % - ‘Nikol’); and HCEL (16 % -and 10 % ‘Retro’ – ‘Nikol’). An unfavourable effect of the processes applied was the increase in ADL (7 % in the irradiated ‘Finezja’ wheat grains and 11 % in the extruded ‘Retro’ grains). The best modification of the chemical composition was achieved by the process of extruding the 'Finezja’ and ‘Nikol’ wheat grains that were moisturized to 25 % prior to the process; the infrared irradiation process resulted in the best modification of the chemical composition of the ‘Nikol’ wheat grains

Nutritional value and the content of minerals in eggs produced in large-scale, courtyard and organic systems

The aim of this study was to determine the content of basic nutrients as well as selected macroand micro-elements in the albumen and yolk of eggs produced at large-scale, commercial poultry production farms (10) as well as in organic (8) and courtyard farms (12). Ten eggs were randomly collected 3 times on each farm. For chemical analyses, the eggs were hard-boiled for 15 min and then stored at a temp. of 4°C until analyzed. The albumen and yolk of hard-boiled eggs were assessed for the content of dry matter, total protein, crude fat and crude ash, and for their energy value (net Atwater equivalents) as well as the concentrations of K, Na, Ca, Mg, P, Fe, Zn, Cu, Se and Mn. No differences were observed in the content of dry matter, total protein and crude ash. However, differences were demonstrated for the crude fat content, the highest (P < 0.05) level of which was found in eggs from the organic system (higher by 60% in albumen and by 17% in yolk than in the other eggs), which was accompanied by an increased energy value of these eggs. In all the analyzed eggs, similar concentrations were noted for Mg (egg white) and P (egg albumen and yolk). The albumen of eggs from the organic system was characterized by the highest (P < 0.05) content of K, Na, Ca, Zn, Se and Mn. In turn, the albumen of eggs from large-scale commercial poultry production farms contained the highest (P < 0.05) levels of Fe, Cu and Se. Yolks of the eggs from the organic system accumulated the highest (P < 0.05) levels of K, Na, Ca, Mg and Fe. In turn, the highest (P < 0.05) concentrations of Zn, Se and Mn were determined in yolks of the eggs produced in the homestead system, and that of Cu – in yolks of the eggs from large-scale commercial production. A highly positive correlation between concentrations of minerals in the albumen and yolk of the analyzed eggs was reported for the following pairs: K-Na, Se (0.998, 0.93); Na-Na (0.949); Ca-Mg, Mn (0.994, 0.951); Mg-Ca, Mn (0.986, 0.982); P-Ca, Mn (0.997, 0.961); Fe-K, Mg, P, Zn (0.999, 0.937, 0.988, 0.999); Zn-Ca, Mn (0.999, 0.945); Se-Cu (0.971) and Mn-Ca (0.902), whereas a negative correlation for: Ca-Fe, Cu (-0.974, -0.994); Mg-Cu (-0.921); P-Fe (-0.933); Zn-Fe (-0.912); Cu-Na (-0.951); Se-K, P, Zn (-0.960, -0.910, -0.962) and Mn-Se (-0.979)