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A suitable microtome sampling technique was used to sample cheese for analysis using FTIR spectroscopy. Well-separated fat- and protein-related bands were obtained in the spectra of Cheddar and Mozzarella cheese samples using this method. The absorbance intensity of the spectra was proportional to the thickness of the sample. The intensity of absorbance and fat- and protein-related bands increased with an increase in the fat and protein content in the sample. Strong and well-separated bands at 1744, 1450, 1240, 1170, and 1115 cm-1 arising mainly from fat content were observed using this method. Bands observed at 1650 and 1540 cm-1 were attributed to the protein present in the cheese. Bands at 1615-1639, 1640-1648, 1650-1658, and 1660-1688 cm-1 corresponding to β-sheet, random coil, helix, and the turns/sheet portion of the secondary structure were observed int he range of the amide I band. Characteristics of spectra for full-fat (FFCC) and reduced-fat Cheddar cheese (RFCC) during ripening were investigated. The absorbance of bands at 1116-1240 from C-C, C-O, C-N stretch, 1461 cm-1 from C-N bend (scissoring), 1744 cm-1 from ester carbonyl groups (fat A), 2850-2930 cm-1 from C-H stretch (fat B), 1650 and 1540 cm-1 from protein amide I and II varied druing cheese aging. Bands at 1116 and1240 cm-1 arising from C-O, C-N, and C-C stretch changed slightly during cheese aging. A correlation coefficient of 0.97 for bands between 1744 and 1167 cm-1 arising from fat, and that of 0.93 at 1650 and 1540 cm-1 arising from protein, respectively, showed that one of these fat or protein groups was highly related to the other. A correlation coefficient of greater than 0.80 among the bands of fat and protein groups indicated a strong interaction in those bands. Correlation of ripening time and absorbance at bands corresponding to each function group was analyzed. A ripening index model was obtained by correlating ripening time with predominant reactive group absorbance peaks. An R2 of 0.83 and 0.59 was obtained for full-fat and reduced fat Cheddar cheese, respectively. Texture development and its correlation with FTIR spectra data for FFCC and RFCC during aging were also studied. RFCC had a higher value of hardness, gumminess, and chewiness than its full-fat counterpart. The values decreased during the early stages of ripening and then increased with time. The change in hardness, adhesiveness, and springiness was expressed as a function of the change in absorbance of the FTIR spectra using multiple regression analysis. An R2 value of 0.67, 0.54, and 0.75 was obtained for full-fat Cheddar cheese, and a value of 0.51, 0.59, and 0.54 was obtained for reduced-fat Cheddar cheese for the respective texture parameters.

The purpose of this dissertation was to realize two studies to evaluate the nutritional value of diets containing full-fat soybean processed by vacuum (FFSvac) or by steam (FFSstm) and of FFSvac and FFSstm for broilers and pigs. The study 1 evaluated the digestibility of diets, of soybeans and the metabolism of broilers fed with diets containing processed full-fat soybean. The experimental design was completely randomized with five treatments (control diet - CD, CD with isometric substitution of 40% FFSvac or FFSstm; diet with FFSvac and diet with FFSstm). The N intake was 23 and 20% less (P<0.01) to the broilers fed with diets containing FFSvac or FFSstm in relation to control group. The excretion, digestibility and absorption of N were not influenced (P>0.05) by the diets. The excretion of energy was 19 and 22% less (P<0.01) to the broilers fed with FFSvac in the diet in relation to control group and those fed with FFSstm in the diet. The diet with FFSvac enhanced (P<0.01) the digestibility and the metabolization of energy. The apparent metabolizable energy corrected for retention of N (MEn) was 12% higher (P<0.01) to the one fed of diet with FFSstm and similar to control diet. The dry matter, protein and ether extract digestibles, the apparent metabolizable energy and MEn were similar (P>0.05) for full-fat soybean processed by vacuum or by steam. The digestibility and absorption of N are not influenced by diets containing full-fat soybean processed by vacuum or by steam. The vacuum processing for full-fat soybean improves the digestibility of gross energy and the apparent metabolizable energy of diets. For the studied soybean types, the digestible nutrients, the apparent metabolizable energy and corrected to nitrogen retention are similar. The study 2 evaluated the digestibility of diets, of soybeans and the metabolism of pigs fed with diets containing processed full-fat soybean. The experimental design was completely randomized with five treatments (control diet - CD, CD with isometric substitution of 40% FFSvac or FFSstm; diet with FFSvac and diet with FFSstm) and four replications with one animal. The intake, urinary excretion of energy and digestible and metabolizable energy were not influenced (P>0.05) by the type of FFS processing. The animals fed diet containing FFSvac excreted 56% more energy (P<0.05) in their feces than animals fed the control diet. The digestion and N metabolism were not influenced (P>0.05) by the type of FFS processing. The digestibility of P, the fecal and the retained P did not differ (P>0.05) between the diets. For FFS, the digestible contents of protein and energy were 10.4 and 4.0% higher (P<0.01) with vacuum processing. The processed soybean does not affect the digestibility of diets neither the metabolism of pigs, except the digestibility of gross energy, which is reduced. The vacuum processing improves the digestible contents of protein and energy of full-fat soybean. / O objetivo desta dissertação foi realizar dois estudos para avaliar o valor nutricional de dietas contendo soja integral processada a vácuo (SIvac) ou a vapor (SIvap) e da SIvac e SIvap para frangos de corte e suínos. O estudo 1 avaliou a digestibilidade das dietas, das sojas e o metabolismo de frangos de corte alimentados com dietas contendo soja integral processada. O delineamento experimental foi inteiramente casualizado, com cinco tratamentos (dieta controle - DC; DC com substituição isométrica de 40% de SIvac ou SIvap; dieta com SIvac e dieta com SIvap). A ingestão de N foi 23 e 20% menor (P<0,01) para as aves alimentadas com dietas com SIvac ou SIvap em relação ao grupo controle. A excreção, digestibilidade e absorção do N não foram influenciadas (P>0,05) pelas dietas. A excreção de energia foi 19 e 22% menor (P<0,01) para as aves alimentadas com SIvac na dieta em relação ao grupo controle e àquele alimentado com dieta com SIvap. A dieta com SIvac melhorou (P<0,01) a digestibilidade e a metabolização da energia. A energia metabolizável aparente corrigida para retenção de N (EMn) foi 12% superior (P<0,01) à da dieta com SIvap e similar a da dieta controle. A matéria seca, proteína e extrato etéreo digestíveis, as energias metabolizável aparente e EMn foram semelhantes (P>0,05) para a soja integral processada a vácuo ou a vapor. A digestibilidade e a absorção do nitrogênio não são influenciadas por dietas contendo soja integral processada a vácuo ou a vapor. O processo a vácuo para a soja integral melhora a digestibilidade da energia bruta e a energia metabolizável aparente das dietas. Para os tipos de soja estudados, os nutrientes digestíveis, a energia metabolizável aparente e corrigida para retenção de nitrogênio são similares. O estudo 2 avaliou a digestibilidade das dietas, das sojas e o metabolismo de suínos alimentados com dietas contendo soja integral processada. O delineamento experimental foi inteiramente casualizado, com cinco tratamentos (dieta controle - DC; DC com substituição isométrica de 40% de SIvac ou SIvap; dieta com SIvac e dieta com SIvap) e quatro repetições de um animal. A ingestão, excreção urinária de energia e energias digestível e metabolizável das dietas não foram influenciadas (P>0,05) pelo processamento da soja. Os animais alimentados com dieta contendo SIvac excretaram 56% mais energia (P<0,05) nas fezes que os alimentados com a dieta controle. A digestão e o metabolismo do N não foram influenciados (P>0,05) pelo tipo de processamento da soja. A digestibilidade do P, o P fecal e absorvido não diferiram (P>0,05) entre as dietas. Para a soja integral, os teores digestíveis de proteína e energia foram 10,4 e 4,0% superiores (P<0,01) com o processamento a vácuo. A soja processada não altera a digestibilidade das dietas nem o metabolismo de suínos, exceto a digestibilidade da energia bruta, que é reduzida. O processamento a vácuo melhora os teores digestíveis de proteína e energia da soja integral para suínos.

<p><strong>Apstrakt je obrađen tehnologijama za optičko prepoznavanje teksta (OCR).</strong></p><p>Ispitan je uticaj heksanskih, etanolnih i etil-acetanih ekstrakata zrna soje i punomasnih hraniva od zrna soje, ekstrudiranog sojinog griza i hidrotermički tretiranog zrna soje, na termičku i katalitičku oksidaciju metil-linoleata primenom ESR spektroskopije i &quot;spin- traping&quot; tehnike. Utvrđeno je da ispitivani ekstrakti inhibiraju termičku i katalitičku oksidaciju metil-linoleata različitim mehanizmima antioksidativnog delovanja. Ustanovljeni antioksidativni efekti dovedeni su u vezu sa vrstama i sadržajem liposolubilnih (a-tokoferol, P-karotin, ukupni ksantofili) i neliposolubilnih antioksidanata (izoflavoni i fitinska kiselina) soje, odnosno u vezu sa termičkim tretmanima primenjenim u proizvodnji ovih hraniva. Ispitani su i uticaji primene različitih rastvarača (etil-acetat, etanol, acetonitril) na antioksidativne efekte ekstrakata neliposolubilnih antioksidanata punomasnih hraniva od zrna soje tokom termičke i katalitičke oksidacije sojinog ulja primenom ESR.</p> / <p><strong>Abstract was processed by technology for Optical character recognition (OCR).</strong></p><p>The influence of hexane, ethanol and ethyl acetate extracts of soybean grain and full-fat feeds of soybean grain, fullfat extruded soybean grits and hydrothermal treated soybean grain on the thermal and catalytic oxidation of methyl linoleate has been studied by ESR spectroscopy and spin-trapping method. It has been found that the investigated extracts inhibit the thermal and catalytic oxidation of methyl linoleate through different mechanisms of antioxidation action. The antioxidative effects found were related to the kinds and contents of soybean liposolubile (a-tocopherol, P-carotene, total xanthophyls) and nonliposolibile antioxidants (isoflavones, phytic acid), that is, they were put in relation to thermal treatments used in production of these feeds. The effects of the application of different solvents on the antioxidative actions of the extracts of nonliposolubile antioxidants of full-fat soybean feeds during thermal and catalytic oxidation of soybean oil have been studied by ESR.</p>

Traditionally, fish meal (FM) and fish oil (FO) have been used extensively in aquafeeds, mainly due to their excellent nutritional properties. However, various reasons dictate the use of sustainable alternatives and the reduction of the dependence on these commodities in fish feeds. Hence, the aim of the present thesis was to investigate the effects of the replacement of FM and FO with two vegetable oils (VO) and an oilseed meal on the growth performance, feed utilization, nutrient and fatty acids (FA) digestibility and tissue FA composition and metabolism in three commercially important European fish species. Specifically, in Experiment I crude palm oil (PO) was used to replace FO in diets for rainbow trout. In Experiments II and III FO was replaced with rapeseed oil (RO) in diets for Atlantic salmon at various dietary protein/lipid levels aiming also at further reductions of FM by using low protein (high lipid) diet formulations. In Experiments II and III the fish were reared at low and high water temperatures, respectively, in order to elucidate, also, the potential effects of temperature. Lastly, the effects of the replacement of FM with full fat soya meal (FFS) in Atlantic cod were investigated in Experiment IV. The results of the present thesis showed no negative effects on growth performance and feed utilization in rainbow trout when FO was replaced with PO. The dietary inclusion of RO improved the growth of Atlantic salmon, possibly, due to changes in the nutrient and FA digestibilities and FA catabolism while, the growth and feed utilization were unaffected by the dietary protein/lipid level. However, the growth of Atlantic cod was affected negatively by the replacement of FM with FFS. The proximate composition of the fish whole body was in most cases unaffected by dietary treatments. The changes in dietary formulations affected the dietary FA compositions and resulted in significant changes in the fish tissue FA compositions. It was clearly shown that the fish tissue total lipid FA composition reflects the FA composition of the diet, although specific FA were selectively utilized or retained in the tissues by the fish. These may have serious implications not only for fish metabolism and growth but also for the quality of the final product, especially in terms of possible reductions of n-3 HUFA.