The total phenolic content (TPC) of common vegetables grown in Ontario was determined by the Folin-Ciocalteu method, and it was found that the broccoli inflorescence had an exceptionally high TPC on average value, followed by cabbage, onion, potato and carrot. The TPC values of darkpurple potatoes and carrots were higher than the common potatoes and carrots. Positive correlations between the TPC and TAA were observed with varied degrees in all vegetables. Choice of cultivar and production practices can be used to increase TPC and TAA in a wide range of vegetables. Insecticide application did not influence the TPC and TAA of broccoli leaves and flowers. Higher N rate decreased the TPC and TAA of cabbage cultivar ‘Huron’ and of carrot. Fungicide and biofungicide applications did not influence TAA in carrots. Fertilizer applications did not influence the TAA of onions, but there was a decrease in TPC. The rate of MAP (mono ammonium phosphate 52% P2O5) affected the TAA of onions, but the influence was inconsistent between two antioxidant assays. High temperature with possibly high rainfall capacity occurred in the year increased the TPC and TAA of most studied vegetable crops. / Ontario Ministry of Agriculture, Food and Rural Affairs/University of Guelph Sustainable Production Systems Program

Master of Science / Food Science Institute / Kadri Koppel / Pomegranate fruits have grown in popularity due to their known beneficial health properties. The objectives of this study were to: 1) determine if flavor differences existed among and within fruits, 2) understand appropriate numbers of replications needed for products that are naturally variable, and 3) compare individual and consensus scores for descriptive sensory analysis over 10 replications of the same product to determine whether differences are found between the methods. Three different sections of the pomegranate fruit were individually evaluated (top, middle and bottom) to determine if flavor differences existed among the fruit sections. Furthermore, the number of repetitions needed in order to obtain small differences in a descriptive panel was calculated. Results showed that pomegranate fruits have natural variation of flavor in the different sections, as well as differences among fruits of the same cultivar. The number of repetitions increased as the differences that wanted to be detected became smaller, and they decreased, as these differences increased. After each sections of fruit were individually evaluated, the panel discussed results and set consensus scores for each attribute. Analysis on mean individual scores and consensus data, along with Principal Component Analysis (PCA) showed that both, individual and consensus methods, provided the same reliable and reproducible information. However, this was evaluated using highly trained panelists. Besides pomegranate juice (PJ), green tea (GT) is one of the most consumed beverages in the world, and has the highest polyphenol content of all teas. Six PJ and GT blends were prepared at different ratios: 90-10, 80-20, 70-30, 60-40, 50-50, 40-60 vol/vol. Lipton GT and Wonderful pomegranates were used to prepare the samples. The objectives of this study were to: 1) determine sensory differences in the samples, 2) consumer acceptance before and after antioxidant information of the samples was provided, and 3) determine their total phenolic content (TPC). Results showed that samples with lower PJ were higher in attributes intensities for Green, and Tea like flavor, while attributes like Berry, Cranberry, Cherry and Sweetness were lower. Consumers liked samples higher in PJ, and sample 40-60 was the least liked. However, overall liking of all samples increased when antioxidant information was given. TPC results showed that pure PJ had the highest content, and as it was mixed with GT, TPC was the sum of the individual percentages of each component. Addition of claims in beverage labels might be a good strategy for consumers to purchase these type of products high in antioxidant content.

Phytochemicals found in grains complement those found in fruits and vegetables. These phytochemicals, though minor compounds, contribute to the antioxidant properties which are related to the health benefits associated with the consumption of whole grain. In this thesis project, nine barley genotypes of diverse origin namely CI2230 from Nepal, CI1248 from Israel, 3 Peruvian genotypes; Peru 3, Peru 16 and Peru 35, Hokuto Hadaka from Japan, EX116; a cross between Moroccan and Canadian genotype, EX83; a cross between two Canadian genotypes and EX127; a cross between Canadian and German genotypes were studied. The genotypes were categorized based on appearance into purple, black and yellow grains. Phenolic acids and flavonoids were identified and quantified in these diverse genotypes using HPLC-ESI-MS analysis. The main classes of dietary flavonoids studied in the barleys were anthocyanins and flavan-3-ols. Phenolic acids were identified and quantified (p-coumaric, ferulic, sinapic, caffeic, vanillic). Three ferulic acid dehydrodimers (8-0-4’ DFA, 8-5’ benzofuran form and 5-5’ DFA) were also identified. The most abundant dimeric flavan-3-ols were procyanidins B3 and prodelphinidin B3. The monomeric unit, (+)-catechin, was the most abundant while catechin glucoside (m/z 451) was also identified. Among the Peruvian genotypes, Peru 16 and Peru 35 exhibited relatively high levels of total PA content. Total phenolic content and antioxidant activities of methanolic, acetone and alkali hydrolyzed extracts of the nine barley genotypes was determined by the Folin- Ciocalteau assay, DPPH radical scavenging assay and oxygen radical absorbance capacity (ORAC assay).The acetone extract exhibited the highest antioxidant capacity using all the methods of analysis. Furthermore, dark colored grains were found to exhibit higher contents of phenolic compounds. The phenolic acids, PAs and anthocyanins identified and quantified had significant contribution to the overall antioxidant capacity of the barley whole grain. Four hull-less genotypes namely CI2230, EX127, CI1248 and Peru 35 were further partially sprouted to establish the effects of sprouting on phenolic acid composition. Partial sprouting was observed to significantly increase the soluble conjugated phenolic acids. The barley genotypes studied were found to contain different quantities of phytochemicals and had high proanthocyanidin content thereby rendering them as alternative sources of antioxidants. Barley sprouts present a possible novel food ingredient with improved properties such as phenolic acid composition and other benefits such as easier incorporation into food products under development.

Phytochemicals found in grains complement those found in fruits and vegetables. These phytochemicals, though minor compounds, contribute to the antioxidant properties which are related to the health benefits associated with the consumption of whole grain. In this thesis project, nine barley genotypes of diverse origin namely CI2230 from Nepal, CI1248 from Israel, 3 Peruvian genotypes; Peru 3, Peru 16 and Peru 35, Hokuto Hadaka from Japan, EX116; a cross between Moroccan and Canadian genotype, EX83; a cross between two Canadian genotypes and EX127; a cross between Canadian and German genotypes were studied. The genotypes were categorized based on appearance into purple, black and yellow grains. Phenolic acids and flavonoids were identified and quantified in these diverse genotypes using HPLC-ESI-MS analysis. The main classes of dietary flavonoids studied in the barleys were anthocyanins and flavan-3-ols. Phenolic acids were identified and quantified (p-coumaric, ferulic, sinapic, caffeic, vanillic). Three ferulic acid dehydrodimers (8-0-4’ DFA, 8-5’ benzofuran form and 5-5’ DFA) were also identified. The most abundant dimeric flavan-3-ols were procyanidins B3 and prodelphinidin B3. The monomeric unit, (+)-catechin, was the most abundant while catechin glucoside (m/z 451) was also identified. Among the Peruvian genotypes, Peru 16 and Peru 35 exhibited relatively high levels of total PA content. Total phenolic content and antioxidant activities of methanolic, acetone and alkali hydrolyzed extracts of the nine barley genotypes was determined by the Folin- Ciocalteau assay, DPPH radical scavenging assay and oxygen radical absorbance capacity (ORAC assay).The acetone extract exhibited the highest antioxidant capacity using all the methods of analysis. Furthermore, dark colored grains were found to exhibit higher contents of phenolic compounds. The phenolic acids, PAs and anthocyanins identified and quantified had significant contribution to the overall antioxidant capacity of the barley whole grain. Four hull-less genotypes namely CI2230, EX127, CI1248 and Peru 35 were further partially sprouted to establish the effects of sprouting on phenolic acid composition. Partial sprouting was observed to significantly increase the soluble conjugated phenolic acids. The barley genotypes studied were found to contain different quantities of phytochemicals and had high proanthocyanidin content thereby rendering them as alternative sources of antioxidants. Barley sprouts present a possible novel food ingredient with improved properties such as phenolic acid composition and other benefits such as easier incorporation into food products under development.

This study covers the extraction of antioxidants from wheat germ / which is the byproduct of the flour-milling industry and a rich source of antioxidants / with Ultrasound Assisted (UAE) and Supercritical Carbon Dioxide (SC-CO2) extractions. Extraction conditions were ultrasonication time (1&ndash / 11 min), temperature (20&ndash / 60&deg / C) and ethanol level (5&ndash / 95%) for UAE, and pressure (148&ndash / 602 bar), temperature (40&ndash / 60&deg / C) and time (10&ndash / 60 min) for SC-CO2 extraction. The extraction conditions were optimized based on yield (%), total phenolic contents (TPC, mg GAE/g extract) and antioxidant activities (AA, mg scavenged DPPH&amp / #729 / /g extract) of the extracts, using Central Composite Rotatable Design. Total tocopherol contents (TTC) of the extracts were determined, as well. UAE (at 60&deg / C) with low ethanol level (~5-30%) and short times (1-3 min) provided protein rich extracts with high yield, medium TPC and AA. On the other hand, with high ethanol level (~90%) and long times (6-11 min), waxy structured extracts with low yield but high TPC and AA were obtained. SC-CO2 extraction at 442 bar, 40&ordm / C and 48 min. enabled almost 100% recovery of wheat germ oil (9% yield) but TPC and AA of the extracts were low. On the contrary, the extracts obtained at lower pressures (~150bar) and shorter times (~10 min) at 50-60&ordm / C had high TPC and AA since the oil yield was low. However, TPC and AA of these extracts were only half of those extracted by UAE. Maximum tocopherol (7.142 mg tocopherol/g extract) extraction was achieved at 240 bar, 56&ordm / C for 20 min. Both of the methods extracted high amounts of tocopherols from roasted wheat germ (SC-CO2 extraction / 0.31 mg tocopherol/g germ, UAE / 0.33 mg tocopherol/g germ) but TTC of the extracts obtained by SC-CO2 extraction was superior compared to 1.170 mg tocopherol/g extract obtained by UAE at 9 min, 58&ordm / C and 95% ethanol level. All these extracts with different characteristics have potential uses in cosmetic and food industry depending on the targeted specific application.

Consommateurs, chercheurs et industriels cherchent de plus en plus à associer à la valeur nutritionnelle des aliments, un effet bénéfique pour la santé. Les aliments caractérisés par des pouvoirs antioxydants élevés semblent correspondre à cette demande. En effet, plusieurs travaux mentionnent les bénéfices santé de ces aliments. Pour répondre à cette demande les industriels mettent en avant ce critère. La fonctionnalité alimentaire, aux bénéfices prometteurs pour la santé publique, reste un concept néanmoins complexe dans la pratique. Ce travail met l’accent sur le fait que les propriétés fonctionnelles d’un aliment ne sont pas directement liées à la composition en ingrédients. L’évaluation du pouvoir antioxydant d'un aliment est dans la plupart des cas réalisée à partir des valeurs des différents ingrédients avant formulation et mise en œuvre des procédés. Pourtant, plusieurs phénomènes sont susceptibles de modifier le pouvoir antioxydant lors de la durée de vie d'un produit alimentaire. D’un point de vue industriel, il est nécessaire de développer une méthode de prédiction de cette activité. Les objectifs de ce travail étaient d’adapter une méthode reproductible et facile à réaliser de quantification du pouvoir antioxydant sur des aliments complexes et de comparer cet index d'un ensemble de produits contenant une large gamme de matières premières. Enfin, a été discuté l’intérêt que représente, dans le domaine des propriétés anti oxydantes, la quantification de l’index créé. Au moment où les industriels vont être amenés à proposer des allégations liées à l’effet bénéfique de l’aliment choisi parmi un échantillon de plus en plus ample / Consumers, researchers and industrialists try more and more to associate with the nutritional value of food, a beneficial effect for the health. Food characterized by high antioxidant powers seems to correspond to this demand. From an industrial point of view, it is necessary to develop methods of predicting this antioxidant capacity. The objectives of this work were to adapt a method reproducible and easy to realize of quantification of the antioxidant power on complex food and to compare this index of a set of products containing a wide range of raw materials. Until now, it has been considered that the use of raw materials characterized by a high antioxidant capacity also leads to a preparation with a high antioxidant activity. We evaluated many of the factors affecting the antioxidant activity of convenience foods (phenol content, effects of formulation, culinary reheating, and preservation) and to provide data on convenience foods consumed by the French population. The total antioxidant capacity of the ethanolic extracts was evaluated by the method of the equivalent Trolox (TEAC) using the radical cation ABTS•+. The concentration of the total phenolic compounds of the same extracts was determined by the Folin-Ciocalteu method. The results show that the food matrix is an important factor for the modulation of activities of antioxidants. A standardised testing protocol for evaluating antioxidative effects is necessary. Then, we discussed the interest of an index, as the industrialists are going to be brought to claim to the beneficial effect of the food chosen among a more and more ample sample

Economically advantageous alternatives to fully explore the antioxidant content of tropical fruit residues from juice processor industries have been currently studied in the State of Alagoas, Brazil. Thus, flour methanolic extracts of acerola (AC), passion fruit (PF) and pineapple (PA) residues were screened for their antioxidant capacity. For this, their total phenolic content, antioxidant capacity toward DPPH and toward the superoxide anion radical, together with analysis of their protective effect against membrane lipid peroxidation, caused by peroxyl radical, were determined in the flour methanolic extracts. In the last case, the phospholipid bilayer biomimetic model with the inclusion of a fluorescent probe was used. The statistical analysis employed the epi info version 6.04d (2001) program and Microsoft excel, using the test t, multivaried analysis and qui-square, considering p < 0.05 as significant. The results of total phenolic content of flour methanolic extracts of AC, PF and PA were 94.6 ± 7.4, 41.2 ± 4.2 and 9.1 ± 1.3 mg of gallic acid equivalents/ g of dry extract, respectively. AC showed the best total phenolic content and antioxidant capacity toward DPPH . PF showed the best antioxidant capacity to superoxide anion radical. Similar indexes of lipid peroxidation protection were observed with both AC and PF residues. Altogether, these data suggest that flour methanolic extracts of AC and PF residues may be useful as antioxidant supplements or food additives, notably the acerola (AC) extracts. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Alternativas economicamente vantajosas com exploração completa do conteúdo antioxidante de resíduos de frutas tropicais de fábricas de sucos foram estudadas no estado de Alagoas, Brasil. Assim, extratos metanólicos de farinhas de resíduos de acerola (FRAC), maracujá (FRMA) e abacaxi (FRAB) foram avaliados quanto a sua capacidade antioxidante. Para isso, foram analisados o conteúdo total de fenóis, a capacidade antioxidante frente aos radicais DPPH e ânion radical superóxido e o efeito de proteção à peroxidação da membrana lipídica, causada pelo radical peroxila, dos extratos metanólicos das farinhas. No ultimo caso, um modelo de membrana bilamelar fosfolipídica com uma sonda fluorescente foi usado. Para a análise estatística, foi utilizado o programa epi info versão 6.04d (2001) e o Microsoft Excel, usando teste t, análise multivariada e qui-quadrado, considerando um p < 0,05 como significativo. Os resultados para o conteúdo total de fenóis dos extratos metanólicos das farinhas de resíduos de acerola (FRAC), maracujá (FRMA) e abacaxi (FRAB) foram 94,6 ± 7,4, 41,2 ± 4,2 e 9,1 ± 1,3 mg de equivalentes de ácido gálico/ g de extrato seco, respectivamente. FRAC mostrou o melhor conteúdo de fenóis e capacidade antioxidante frente ao radical DPPH . FRMA mostrou a melhor capacidade antioxidante frente ao ânion radical superóxido. Resposta similar foi observada entre FRAC e FRMA quanto à proteção frente a peroxidação da membrana lipídica. De modo geral, estes dados sugerem que extratos metanólicos de farinhas de FRAC e FRMA podem ser úteis como suplementos antioxidantes ou aditivos alimentares, em especial, o extrato de acerola.