Fractions from white and tannin sorghums were processed into extrudates, thick porridges, and breads. The effects of sorghum type and fraction on the in vitro starch availability of the products were evaluated, and the estimated glycemic indexes (EGI) of the products were obtained. Sorghum extrudates were significantly more slowly digested than corn meal extrudates for all preparation methods (whole, cracked and decorticated kernels). Furthermore, tannin extrudates were less digestible than white sorghum extrudates. The soft endosperm nature of the tannin sorghum limited friction formation inside the extruder, reducing starch gelatinization. On the other hand, condensed tannins also interfered with the starch availability for digestion. White sorghum was more 'suitable' for extrusion, giving extrudates with higher starch degradation and expansion than the tannin sorghums. However, tannin sorghums also gave acceptable products offering the benefit of lower EGI values. Sorghum porridges were more slowly digested than a corn flour porridge when using whole and decorticated flours. In addition, tannin sorghum porridges had a lower starch digestibility compared to all the samples. Tannin sorghum flours produced soft porridges with enhanced initial starch digestibility. However, condensed tannins seemed to offset the starch digestion by limiting starch availability. All sorghum porridges had significantly lower EGI values than the corn porridge. Extrudates and porridges had reduced starch digestibilities and EGI values when using whole grains compared to using the decorticated fractions. This was observed in both the white and the tannin sorghum. Therefore, whole-grain products from sorghum have health benefits attributed to whole grain foods and slower digesting starches; for instance, prevention and treatment of diseases such as diabetes, insulin resistance, obesity, cardiovascular disease, and some types of cancer. When 12% of tannin bran was added to a wheat bread formulation, a slower rate of starch digestion was observed compared to a wheat bread. The high concentration of non-starch components of the bran (i.e. dietary fiber, condensed tannins) affected starch digestion. The addition of tannin sorghum bran significantly reduced the EGI value of wheat bread, besides being a natural source of brown color, and an excellent source of antioxidants and dietary fiber.

Barley grain is one of the main sources of feed for ruminants in Canada. Although barley varieties may have similar chemical composition, they exhibit different rumen degradation characteristics and nutrient availabilities. These biological differences may be related to structural chemical make-up or structural features among the varieties. The objectives of this study were to use the in situ technique and two Mid-IR Spectroscopy techniques, Diffuse Reflectance Fourier Transform IR Spectroscopy (DRIFT) and Synchrotron-based Fourier Transform IR Microspectroscopy (SFTIRM) to determine ruminal nutrient availabilities and inherent structural features in the hull, seed and endosperm of six barley varieties (AC Metcalfe, McLeod, CDC Dolly, CDC Helgason, CDC Trey, and CDC Cowboy) and to study the relationships between structural characteristics, mean and median particle size and nutrient availability. The nylon bag technique was used to incubate coarsely dry-rolled barley samples for 0, 2, 4, 8, 12, 24 and 48 h in the rumen of three mature Holstein dry dairy cows, which were ruminally cannulated. The rumen degradation kinetics of dry matter (DM), crude protein (CP) and starch were determined using first order degradation kinetics equations. Results indicated that there were significant differences in the mean and median particle size, degradation kinetics of each individual nutrient (DM, CP, and starch) among the six barley varieties. CDC Helgason showed the lowest degradation rate and extent of all nutrients (DM, CP, and starch) among the six barley varieties with larger particle size. Compared with other five varieties, CDC Helgason may be more suitable for ruminants feeding because of the lowest degradation rate and extent. The results also revealed a strong correlation between median particle size and the rate and extent of rumen degradation.<p> The results also showed that both DRIFT and SFTIR techniques associated with uni- and two multi- variate analyses were capable to efficiently discriminate and classify the inherent molecular structural features among the different varieties of barleys. Uni-variate analyses were conducted using both the DRIFT spectroscopy (hull and whole seed sample) and SFTIR microspectroscopy (endosperm tissue). The results from hull samples showed significant differences in the peak area of aromatic lignin, cellulosic compound, and total carbohydrates (CHO), and the ratio of lignin to cellulosic compound among the six barley varieties. The results from whole seed samples showed significant difference in the peak area and height of Amide I, peak area of total CHO and structural CHO (cellulosic), and the ratio of Amide I to total CHO area, and the ratio of total CHO to structural CHO. Significant differences were also found in the SFTIR results from endosperm tissue. With two multivariate spectral analysis techniques: Agglomerative hierarchical cluster (AHCA) and Principal component analyses (PCA) applied on whole seed sample, the CDC Helgason was distinguished from AC Metcalfe, CDC Dolly, McLeod and CDC Cowboy in fingerprint (1800-800 cm-1) and CHO region (1185-800 cm-1), from AC Metcalfe, McLeod and CDC Cowboy in protein region (1715-1485 cm-1). Information from this study involving probing the seed internal structure of barley may provide a further insight as to why barley varieties exhibit different rumen degradations.

Most of the calories in cereal foods come from starch. Decreasing starch digestibility is fundamental to prevent obesity and diabetes. This study investigated interactions of condensed tannins (proanthocyanidins-PA) and other sorghum phenolic compounds with starch molecules and their effect on in vitro starch digestibility. High tannin (predominant in large molecular weight PA, 80%), black (monomeric polyphenols) and white (low in polyphenols) sorghum phenolic extracts were cooked with starches varying in amylose content. Starch pasting properties, polyphenol profile and in vitro starch digestibility were evaluated. Unlike other treatments, samples with tannin phenolic extracts had significantly (P ≤ 0.05) lower setback in the test using a Rapid Visco Analyser (RVA) compared to control. The same treatments had the least extractable phenol and PA contents after cooking with all starches. These evidences suggest interactions between starch molecules and PA. Furthermore, after mixing tannin phenolic extracts with pure amylose/amylopectin, extractable polymeric PA was in much lower concentration (62% less) in presence of amylose compared to amylopectin. This drop in concentration increased to 85% when purified tannin extract (90% polymeric PA) was used. This indicates a stronger interaction between amylose and large molecular weight PA. When high amylose starch was used in an autoclave cooking/cooling technique, the RS content of control (26.4%) was similar (P > 0.05) to samples with black phenolic extracts (27%); samples with tannin phenolic extracts increased RS to about 40%. The RS increased to 46% when purified tannin extract was used. All these evidences suggest that sorghum condensed tannins, specifically the polymeric PA, directly interacted with amylose, increasing RS content, whereas the monomeric polyphenols did not. This study opens opportunities to use tannin sorghum to develop products for diabetics and weight control, high in dietary fiber and natural dark color. In the other part of this project, polyphenols from black and tannin sorghum bran were extracted using an Accelerated Solvent Extractor (ASE) and eco-friendly solvents such as water, and mixtures ethanol/water. ASE at 120 and 150 degrees C using 50 and 70% ethanol/water was efficient in extracting as much phenols (45 mg GAE/g) and 12% more antioxidants (628 μmol TE/g) from black sorghum compared to conventional methods using aqueous acetone and acidified methanol. Therefore, ASE extracts from black sorghum could be used in beverages and in colorants containing high antioxidant content.

Barley grain is one of the main sources of feed for ruminants in Canada. Although barley varieties may have similar chemical composition, they exhibit different rumen degradation characteristics and nutrient availabilities. These biological differences may be related to structural chemical make-up or structural features among the varieties. The objectives of this study were to use the in situ technique and two Mid-IR Spectroscopy techniques, Diffuse Reflectance Fourier Transform IR Spectroscopy (DRIFT) and Synchrotron-based Fourier Transform IR Microspectroscopy (SFTIRM) to determine ruminal nutrient availabilities and inherent structural features in the hull, seed and endosperm of six barley varieties (AC Metcalfe, McLeod, CDC Dolly, CDC Helgason, CDC Trey, and CDC Cowboy) and to study the relationships between structural characteristics, mean and median particle size and nutrient availability. The nylon bag technique was used to incubate coarsely dry-rolled barley samples for 0, 2, 4, 8, 12, 24 and 48 h in the rumen of three mature Holstein dry dairy cows, which were ruminally cannulated. The rumen degradation kinetics of dry matter (DM), crude protein (CP) and starch were determined using first order degradation kinetics equations. Results indicated that there were significant differences in the mean and median particle size, degradation kinetics of each individual nutrient (DM, CP, and starch) among the six barley varieties. CDC Helgason showed the lowest degradation rate and extent of all nutrients (DM, CP, and starch) among the six barley varieties with larger particle size. Compared with other five varieties, CDC Helgason may be more suitable for ruminants feeding because of the lowest degradation rate and extent. The results also revealed a strong correlation between median particle size and the rate and extent of rumen degradation.<p> The results also showed that both DRIFT and SFTIR techniques associated with uni- and two multi- variate analyses were capable to efficiently discriminate and classify the inherent molecular structural features among the different varieties of barleys. Uni-variate analyses were conducted using both the DRIFT spectroscopy (hull and whole seed sample) and SFTIR microspectroscopy (endosperm tissue). The results from hull samples showed significant differences in the peak area of aromatic lignin, cellulosic compound, and total carbohydrates (CHO), and the ratio of lignin to cellulosic compound among the six barley varieties. The results from whole seed samples showed significant difference in the peak area and height of Amide I, peak area of total CHO and structural CHO (cellulosic), and the ratio of Amide I to total CHO area, and the ratio of total CHO to structural CHO. Significant differences were also found in the SFTIR results from endosperm tissue. With two multivariate spectral analysis techniques: Agglomerative hierarchical cluster (AHCA) and Principal component analyses (PCA) applied on whole seed sample, the CDC Helgason was distinguished from AC Metcalfe, CDC Dolly, McLeod and CDC Cowboy in fingerprint (1800-800 cm-1) and CHO region (1185-800 cm-1), from AC Metcalfe, McLeod and CDC Cowboy in protein region (1715-1485 cm-1). Information from this study involving probing the seed internal structure of barley may provide a further insight as to why barley varieties exhibit different rumen degradations.

This study utilized two diets (25 and 35% crude protein) fed at 10 different rates to produce differences in shrimp specific growth rate which were regressed against daily digestible protein (DP) and digestible energy (DE) intake to estimate daily DP and DE requirements for sub-adult L. vannamei. Apparent DP and DE requirement for maximum growth decreased throughout the 7-week trial as shrimp size increased. Mean apparent daily DP requirement for 7.69 to 13.08-g L. vannamei fed the 25% protein diet was 6.31 g DP kg-1 BW d-1 while the 35% protein diet produced a mean apparent daily DP requirement of 8.00 g DP kg-1 BW d-1 for 8.11- to 13.79-g L. vannamei. Maintenance requirements were estimated by regressing DP feed allowances back to zero weight-gain and were 1.03 g DP kg-1 BW d-1 for shrimp fed the 25% protein diet and 1.87 g DP kg-1 BW d-1 for shrimp fed the 35% protein diet. Mean apparent daily DE requirement for shrimp fed the 25% protein diet was 402.62 kJ DE kg-1 BW d-1 while the 35% protein diet produced an apparent daily DE requirement of 334.72 kJ DE kg-1 BW d-1. Mean apparent daily DE maintenance requirements for shrimp fed the 25% protein diet was 66.23 kJ DE kg-1 BW d-1 while the requirement was 78.82 kJ DE kg-1 BW d-1 for shrimp fed the 35% protein diet. Daily DP and DE requirements were also determined by regressing whole-body protein or energy change against daily DP and DE intake and were similar to those values obtained by regressing change in body weight against daily DP and DE intake. Another component of this project involved evaluating 32 different feedstuffs for dry matter, protein and energy digestibility coefficients. Fish meal apparent crude protein digestibility coefficients as a group were higher than all other ingredient classifications except purified ingredients. Protein in 48% soybean meal and 90% isolated soybean protein were significantly more digestible than protein found in fish, animal and marine meals tested. This data will improve the quality and reduce the cost of commercial shrimp feeds.

Fractions from white and tannin sorghums were processed into extrudates, thick porridges, and breads. The effects of sorghum type and fraction on the in vitro starch availability of the products were evaluated, and the estimated glycemic indexes (EGI) of the products were obtained. Sorghum extrudates were significantly more slowly digested than corn meal extrudates for all preparation methods (whole, cracked and decorticated kernels). Furthermore, tannin extrudates were less digestible than white sorghum extrudates. The soft endosperm nature of the tannin sorghum limited friction formation inside the extruder, reducing starch gelatinization. On the other hand, condensed tannins also interfered with the starch availability for digestion. White sorghum was more 'suitable' for extrusion, giving extrudates with higher starch degradation and expansion than the tannin sorghums. However, tannin sorghums also gave acceptable products offering the benefit of lower EGI values. Sorghum porridges were more slowly digested than a corn flour porridge when using whole and decorticated flours. In addition, tannin sorghum porridges had a lower starch digestibility compared to all the samples. Tannin sorghum flours produced soft porridges with enhanced initial starch digestibility. However, condensed tannins seemed to offset the starch digestion by limiting starch availability. All sorghum porridges had significantly lower EGI values than the corn porridge. Extrudates and porridges had reduced starch digestibilities and EGI values when using whole grains compared to using the decorticated fractions. This was observed in both the white and the tannin sorghum. Therefore, whole-grain products from sorghum have health benefits attributed to whole grain foods and slower digesting starches; for instance, prevention and treatment of diseases such as diabetes, insulin resistance, obesity, cardiovascular disease, and some types of cancer. When 12% of tannin bran was added to a wheat bread formulation, a slower rate of starch digestion was observed compared to a wheat bread. The high concentration of non-starch components of the bran (i.e. dietary fiber, condensed tannins) affected starch digestion. The addition of tannin sorghum bran significantly reduced the EGI value of wheat bread, besides being a natural source of brown color, and an excellent source of antioxidants and dietary fiber.

Orientador: Telma Teresinha Berchielli / Coorientador: Roberta Carrilho Canesin / Banca: Antonio Fernando Bergamaschine / Banca: Marcos Veiga dos Santos / Banca: Ricardo Andrade Reis / Banca: Mauro Dal Secco de Oliveira / Resumo: Foram realizados três experimentos, sendo o primeiro na avaliação de indicadores em estudos com novilhas leiteiras para a determinação da produção fecal, fluxo de digesta e digestibilidade. O segundo experimento foi conduzido visando avaliar os efeitos de dietas com diferentes fontes protéicas (farelo de soja, farelo de algodão, farelo de amendoim e farelo de girassol) no metabolismo, e o terceiro no desempenho produtivo e medidas corporais de novilhas mestiças Holandês/Zebu, alimentadas com 60% de cana-de-açúcar e 40% de concentrado na dieta. No primeiro e segundo experimentos foram utilizadas oito novilhas mestiças Holandês/Zebu, distribuídas em duplo quadrado latino 4x4. No terceiro, foram utilizadas 24 novilhas mestiças Holandês/Zebu distribuídas no delineamento experimental utilizado, o qual foi em blocos casualizados, constituído por seis repetições e quatro tratamentos. Os indicadores Cr-EDTA, YbCl3 e o FDNi não estimaram produção fecal de forma eficiente (P<0,05), obtendo resultado de 1,64, 1,71 e 2,71 kg/dia, respectivamente. O valor estimado de fluxo de matéria seca pela associação Cr-EDTA/YbCl3, utilizada na forma de duplo indicador, foi o mais confiável, devido a melhor recuperação dos indicadores externos (Cr-EDTA e YbCl3), que obtiveram médias de 89% e 85%, respectivamente, em comparação ao interno (FDNi), que obteve média 67%. Os coeficientes de digestibilidade ruminal e pós ruminal dos nutrientes avaliados, estimados pela associação Cr-EDTA/YbCl3, também foram considerados os melhores valores, em consequência do valor de fluxo de matéria seca estimado por esta associação. Os valores de digestibilidade aparente total, ruminal e pósruminal observados não apresentaram diferenças estatísticas para as fontes proteicas avaliadas (P>0,05). A taxa de passagem... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Experiments were carried, the first evaluating indicators in studies with dairy heifers for the determination of fecal output, digestibility and digest flow. The second experiment was conducted to evaluate the effects of diets with different protein sources (soybean meal, cottonseed meal, peanut meal and sunflower meal) in metabolism, and the third on growth performance and body measurements of heifers' crossbred Holstein / Zebu fed 60% of sugar cane and 40% concentrate diet. In the first and second experiments were used eight heifers' crossbred Holstein / Zebu, distributed in two 4x4 Latin square. In the third, we used 24 crossbred heifers' Holstein / Zebu distributed in the experimental design, which was a randomized blocks design, consisting of six replicates and four treatments. The indicators Cr-EDTA and YbCl3 iNDF not estimate fecal output efficiently (P<0.05), obtaining a result of 1.64, 1.71 and 2.71 kg / day, respectively. The estimated flow of dry matter by the association Cr-EDTA/YbCl3, used in the form of double indicator, was the more confident due to better recovery of external markers (Cr-EDTA and YbCl3), who obtained 89% and 85% values of average, respectively, compared to the internal indicator (iNDF), who obtained an average of 67%. The coefficients of ruminal and post ruminal digestibility of nutrients, Cr-EDTA/YbCl3 estimated by the association, were also considered the best values in consequence of the flow of dry matter estimated by the association. The total apparent digestibility, ruminal and post ruminal observed no significant differences for the protein sources tested (P>0.05). The passage rate and retention time were not significant differences between protein sources (P>0.05) and mean values of 1.94 kg / day, 3.43% h and 30.47 hours, respectively. The excretion of purine... (Complete abstract click electronic access below) / Doutor

Master of Science / Department of Grain Science and Industry / Yong Cheng Shi / Resistant starch (RS) is notable for having several health benefits in humans, including glucose control and intestinal well-being. Pullulanase is able to debranch amylopectin and result in higher RS content. Different levels of pullulanase have been used to debranch waxy maize starch in the literature, but the changes of structure during debranching are well documented. In this study, waxy maize starch was cooked and debranched by pullulanase with 80, 160 and 240 New Pullulanase Unit Novo (NPUN)/g starch pullulanase. One NPUN was defined as the amount of enzyme, which, under standard conditions, hydrolyzes pullulan, liberating reducing carbohydrate with reducing power equivalent to 1 µmole glucose per minute. The structure of waxy maize starch during debranching was investigated and the digestibility of the debranched products was measured. When pullulanase was increased from 80 to 240 NPUN/g, more amylopectin was debranched in the same debranching time, and the degree of crystallinity and the RS content increased. After the debranched starches were crystallized at 25°C for 24 hours, the RS contents were greater than 63%. When heated and recrystallized under highly regulated conditions, the linear material formed crystallites of a range of geometries, including spherulites of a highly organized structure. Debranched waxy maize starches were used to produce crystalline structure under four conditions: spherulites formed by adding ethanol and crystallized at 4°C (ES4); spherulites formed in water (WS4) at 4°C; particles formed at 50°C (WS50); and spherulites formed at 50°C then further precipitated at 4°C (WS50-4). Spherulites formed at 50°C (WS50) had a higher proportion of smaller molecules than existed in the parent starch (Rh<15nm). ES4 and WS4 were B-type crystalline structure; whereasWS50 and WS50-4 were A-type crystalline structure. ES4 had a larger proportion of molecules with a low degree of polymerization and the RS content was also the lowest of the four samples. With cooling from 50°C to 4°C (WS50-4), the RS content was increased from 60% to 73%. ES4 and WS50-4 contained particles with spherical symmetry and WS4 had partial radial symmetry with some distortions, whereas WS50 displayed oblate particles with a parallel crystal structure.

The objective of this study was to evaluate digestibility of cubed hay as a feedstuff for ruminants. Angus (n=6), Hereford (n=3), and Charolais (n=3; total n=12; 226 ± 21.8kg) steers, stratified by breed, were randomly assigned to 3 treatment groups: 1) hay; 2) chopped; 3) cubed. There was no difference (P > 0.05) of DMI or digestibility of DM, OM, NDF, ADF, hemicellulose, and energy among treatments. Steers consuming hay digested more CP than those consuming chopped. Steers consuming cubed digested less CP than those consuming hay or chopped. More fat was digested by steers consuming hay or chopped than by those consuming cubed. Steers consuming cubed retained more nitrogen than those consuming chopped. Those consuming hay were intermediate. Nitrogen metabolized was greater for steers consuming hay than for steers consuming chopped. Those consuming cubed were intermediate. Steers consuming hay and cubed had greater metabolizable protein than those consuming chopped.

The objective of this study was to evaluate the lighter fraction of DDGS as a possible feedstuff for cattle. To accomplish this, a digestion trial was performed to determine nutrient digestibility and crude protein retention by steers consuming the lighter fraction of DDGS. Steers received L, a diet containing the lighter fraction of DDGS, D, a diet containing whole DDGS, or C, a control diet. Steers receiving L consumed less DM than steers receiving D and C. CP retention and digestibilities of DM, OM, ash, NDF, ADF, HC, and energy did not differ among steers in different treatment groups. Fat digestibility was greatest for steers consuming L and D. Steers consuming L digested more CP than steers receiving C, with steers consuming D being in between. These data suggest that the lighter fraction of DDGS can be effectively fed to cattle without adversely affecting digestibility.