Prospección y caracterización preliminar in situ de cinco especies de sapotaceas en Nicaragua

Este trabajo consistió en una prospección (1994) y caracterización in situ (1995-1998) de cinco especies de la familia Sapotaceas en Nicaragua. Con fichas de inventario y fichas etnobotánicas se recopiló la información, obteniéndose 246 registros de Manilkara zapota L. (níspero), 287 de Chrysophyllum cainito L. (caimito), 508 de Pouteria sapota Jacquin (zapote rojo), 49 de Pouteria viridis Pittier (zapote verde) y 46 muestras de Pouteria campechialia H.B.K (zapote mico). Se determinaron estadísticos básicos, análisis Cluster y Componentes Principales. Estas especies tienen uso medicinal y se encuentran generalmente en huertos familiares y muy poco como plantaciones comerciales, los frutos se comercializan en mercados locales, excepto P. campechiana. P. sapota, P. viridis y M. zapota son las más apetecidas como fruta fresca, estos presentaron frutos con promedios de 323 y 95 gramos, algunos con peso superior a los 1000 gramos, sabor dulce, buen aroma, jugosidad y fácil desprendimiento de pulpa. Se muestrearon frutos de M. zapota de más de 500 gramos, el promedio fue 134 gramos, de forma redonda, alargada y ovalada, y sabor muy dulce. C. cainita presentó peso promedio de más de 100 gramos; los frutos son muy dulces, cáscara verde, blanca y morada. En Rivas e isla de Ometepe, Leon, Chinandega, Masaya y Granada se encontro la mayor diversidad fenotipica y frutos de mejor calidad (zapote y nispero). Este estudio demuestra que existe gran diversidad genetica en el pais que tiene gran potencial.

Comportamiento productivo de vacas lecheras alimentadas con Moringa oleifera fresco o ensilado: efecto sobre producción, composición y características organolépticas de leche y queso

Moringa oleiferafresca o ensilada, se comparó con una dieta control basada en Pennisetum purpureum cv CT-115+ concentrado comercial como dieta única para vacas lecheras. Se evaluó el efecto de las dietas experimentales sobre el consumo y la digestibilidad, la producción y composición de la leche, y las características organolépticas de leche y queso. Seis vacas lecheras fueron utilizadas en un experimento cuadrado latino 3x3, con dos repeticiones. Las dietas de Moringa fueron isocalóricas respecto a la dieta control. El consumo de materia seca (MS) de los tratamientos de Moringa fue significativamente mayor (P<0.05) que el control. Moringafresca tuvo el mayor consumo (P<0.001) de materia orgánica (MO), proteína bruta (PB), fibra detergente neutra (FDN), fibra detergente ácido (FDA) en comparación con la dieta de control. Los mayores coeficientes de digestibilidad (P<0.05) se manifestaron en el tratamiento control respecto a los tratamientos de Moringa(fresca o ensilada), con la excepción de la digestibilidad de la PB. La producción de leche del tratamiento de Moringa ensilado fue ligeramente inferior (9%) respecto a los otros dos tratamientos. La composición de la leche fue similar entre todos los tratamientos. Sin embargo, la leche del tratamiento de Moringa fresca presentó un sabor y aroma a hierba, significativamente diferente (P<0.001) de los otros dos tratamientos, a pesar de que era normal en color y apariencia. No se observaron diferencias organolépticas entre la leche del tratamiento control y el tratamiento de ensilaje de Moringa. Igual comportamiento se encontró en el queso elaborado a partir de la leche de los tres tratamientos. El análisis financiero favorece a los tratamientos de Moringa. La conclusión es que el ensilaje de Moringase puede utilizar para alimentar vacas lecheras en grandes cantidades para producir cantidades similares y misma producción de leche, características organolépticas. calidad de la leche que las dietas convencionales.

Herstellung und Zusammensetzung von asiatischen Fischsaucen

Abstract Fish sauce belongs to the most important condiments in Southeast Asian cuisine. It is a clear, amber to reddish liquid with an intensive smell. Fish sauce is used instead of salt for nearly each meal. Asian fish sauce is made from anchovies and other small fish. For the traditional process whole fresh fish are mixed with salt in the ratio 1:1 to 6:1 in wooden, clay or concrete tanks at tropical temperatures for 6 to 18 months. The liquefaction of the fish tissue is due to the action of endogenous enzymes in fish and exogenous enzymes from bacteria. During the fermentation amino acids, peptides and a lot of other substances are built, which are responsible for the characteristic aroma and flavour of these sauces. You can buy pure fish sauce, diluted fish sauce and fish sauce made from other types of animals like mussels, prawns and squids. In single Asian countries there are different national standards for the quality of fish sauces. In order to get a general idea of these products we have bought 16 fish and two oyster sauces from the retail trade in Hamburg and analyzed them with physical, chemical, sensory and microbiological methods. Kurzfassung Fischsauce gehört zu den wichtigsten Würzsaucen in der südostasiatischen Küche. Es ist eine klare, bernsteinfarbene bis rötlichbraune, sehr intensiv riechende Flüssigkeit. Sie wird anstelle von Salz verwendet und daher fast zu jedem Essen gereicht. Zur Herstellung von Fischsaucen werden hauptsächlich Anchovis und ähnliche kleine Fische verwendet. Bei der traditionellen Herstellung werden die ganzen Fische mit Meersalz in einem Holzfass, Tongefäß oder Betontank im Verhältnis 1:1 bis 6:1 gemischt. Während der anschließenden 6 – 18 Monate dauernden Lagerung bei tropischen Temperaturen bauen sich die Gewebeproteine durch fischeigene Enzyme und Mikroorganismen ab. Bei diesem mehrmonatigen Fermentationsprozess entstehen die für den Geschmack wichtigen Aminosäuren, Peptide und Aromastoffe. Es gibt neben reiner Fischsauce, auch verdünnte Fischsauce und Fischsaucen aus anderen Tieren wie Muscheln, Garnelen und Tintenfische. In den einzelnen asiatischen Ländern gibt es unterschiedliche nationale Qualitätsstandards. Um diese Produktgruppe näher kennen zu lernen, haben wir 16 Fisch- und 2 Austernsaucen aus dem Einzelhandel (Hamburg) mit physikalischen, chemischen, sensorischen und mikrobiologischen Verfahren untersucht.

Effects of Zataria multiflora Boiss essential oil and nisin on the growth of Staphylococcus aureus in light salted silver carp fillet (Hypophthalmichthys molitrix)

There is an increasing demand in developing newer and safer methods in preserving food products.Among which herbal additives seem to attract evermore attention recently.the major advantage of herbal additives is due to their favorable aroma besides their antimicrobial effects and less expensive than chemical additives. Zataria multiflora Boiss is a native Iranian herb which is used vastly as a food preserver essential oils and also medical usage. Metabolites of harmless bacteria, such as Nisin are also known to be safe preservatives that have antimicrobial activity. However to establish the usefulness of natural antimicrobial preservatives, they must be evaluated alone and in combination with other preservation factors to determine whether there are synergistic effects in rigid media . In this study were evaluated the effects of different concentrations of Zataria multiflora (EO 0, 0.005, 0.015, 0.045, 0.135, 0.405 ,0.810 %) and Nisin(0, 0.15, 0.25, 0.75 μg/ml) and Storage time (up to 21 days) on growth of Staphylococcus aureus ATCC 6538 in a food model system(light salted fish of silver carp, Hypophthalmichthys molitrix). The results on growth of S. aureus were evaluated using SPSS 15.0 statistical software (SPSS 15.0 for windows, SPSS Inc.) and analyzed the logarithm of total count of the bacteria by Tukey Test. Results were considered statistically significant when P≤0.05. The growth of Staphylococcus aureus was affected significantly(P<0.05) by EO and Nisin and also combinations of EO and Nisin. Samples treated with 0.135, 0.405 and 0.810% of thyme essential oil showed a significant decrease on the growth of the bacteria compared with an treated samples(P<0.05). No significant difference was seen on the growth of S.aureus in samples treated with lower concentrations of Z.multiflora(below 0.045%) and untreated group(P>0.05). The most inhibitory effects were seen in samples treated with 0.405% and 0.810% of thyme essential oil until 9 and 12 days after storage,respectively. Also there was significant inhibtory effect(P<0.05) in different concentration of nisin on the organism compared with an treated samples. The synergism effects of the Eo and nisin on the growth rate of the bacteria was significant (P<0.05) compared with untreated samples and samples treated with the Eo or nisin, only. Synergismic effects was observed at concentration of 0.405 and 0.810% of Z. multiflora essential oil with 0.25 μg/ml Nisin, respectively until 15 days after storage. As expected it is preferred to apply the least possible amounts of additives in food preserving that not only are effective and safe but are economically justifiable.

Farming a new economically viable fish species: Kisinja (Barbus altianalis)

Kisinja (Barbus altianalis)is an indigenous omnivorous fish, of high economic value in Uganda. It was widely distributed in most lakes and rivers in the country but its stocks were depleted due to overfishing and degradation of its natural habitat. 1t can grow up to a maximum length of 120m and a weight of 15kg in the wild and grows faster, attains larger size than commonly farmed fishes in Uganda, including the Nile tilapia, the African catfish, and mirror carp. Kisinja is a highly valuable table fish with good taste and aroma especially when smoked. Increased production of Kisinja is therefore necessary to meet economic and nutritional benefits of the communities and conservation of the spedes.

Equipe técnica de abacaxi comemora 30 anos de atividades e realizações.

A Embrapa Mandioca e Fruticultura Tropical instituiu há poucos anos atrás, os ?Dias dos Produtos? pesquisados pelo Centro. A data escolhida para a comemoração do ?Dia do Abacaxi? foi 04 de novembro. Isso porque foi nessa data que o navegador genovês, Cristóvão Colombo, em uma de suas históricas viagens, aportou na ilha de Guadalupe, e lá encontrou o abacaxi sendo cultivado pelos nativos. Impressionado pela beleza e forma da planta, pelo aroma e sabor do fruto, coletou alguns exemplares e os levou para a Europa, onde esse fruto teve grande aceitação. Em 2007, a comemoração do ?Dia do Abacaxi? foi adiada e ocorreu no dia 10/12/2007 à tarde, e também teve uma programação diferente, da qual constou, além da confraternização informal de praxe, uma sessão técnica composta de um painel. Nesse painel foram apresentadas quatro palestras referentes a alguns dos impactos e avanços obtidos pela Equipe Técnica de Abacaxi /ETA, da Unidade, ao longo de sua existência. Os temas das palestras versaram sobre o VI Simpósio Internacional de Abacaxi (pela primeira vez realizado no continente sulamericano e, mais especificamente, no Brasil); fitossanidade (fusariose) e produção integrada (com destaque para o Tocantins); melhoramento genético (híbridos resistentes e herança da resistência); usos alternativos do abacaxi (como ornamental, flor de corte, de vaso e de jardim); e aspectos econômicos e de mercado (peso médio do fruto brasileiro e posição do Brasil no mercado internacional). As palestras foram apresentadas, respectivamente, pelos pesquisadores Domingo Haroldo Reinhardt (coordenador do simpósio), Aristóteles Pires de Matos, José Renato Santos Cabral, Janay dos Santos-Serejo, Fernanda Vidigal Duarte Souza e Clóvis Oliveira de Almeida.

Fundamental studies of sourdoughs fermented with Weissella cibaria and Lactobacillus plantarum: influence on baking characteristics, sensory profiles and in vitro starch digestibility of gluten-free breads

The application of sourdough can improve texture, structure, nutritional value, staling rate and shelf life of wheat and gluten-free breads. These quality improvements are associated with the formation of organic acids, exopolysaccharides (EPS), aroma or antifungal compounds. Initially, the suitability of two lactic acid bacteria strains to serve as sourdough starters for buckwheat, oat, quinoa, sorghum and flours was investigated. Wheat flour was chosen as a reference. The obligate heterofermentative lactic acid bacterium (LAB) Weissella cibaria MG1 (Wc) formed the EPS dextran (a α-1,6-glucan) from sucrose in situ with a molecular size of 106 to 107 kDa. EPS formation in all breads was analysed using size exclusion chromatography and highest amounts were formed in buckwheat (4 g/ kg) and quinoa sourdough (3 g/ kg). The facultative heterofermentative Lactobacillus plantarum FST1.7 (Lp) was identified as strong acidifier and was chosen due to its ubiquitous presence in gluten-free as well as wheat sourdoughs (Vogelmann et al. 2009). Both Wc and Lp, showed highest total titratable acids in buckwheat (16.8 ml; 26.0 ml), teff (16.2 ml; 24.5 ml) and quinoa sourdoughs (26.4 ml; 35.3 ml) correlating with higher amounts of fermentable sugars and higher buffering capacities. Sourdough incorporation reduced the crumb hardness after five days of storage in buckwheat (Wc -111%), teff (Wc -39%) and wheat (Wc -206%; Lp -118%) sourdough breads. The rate of staling (N/ day) was reduced in buckwheat (Ctrl 8 N; Wc 3 N; Lp 6 N), teff (Ctrl 13 N; Wc 9 N; Lp 10 N) and wheat (Ctrl 5 N; Wc 1 N; Lp 2 N) sourdough breads. Bread dough softening upon Wc and Lp sourdough incorporation accounted for increased crumb porosity in buckwheat (+10.4%; +4.7), teff (+8.1%; +8.3%) and wheat sourdough breads (+8.7%; +6.4%). Weissella cibaria MG1 sourdough improved the aroma quality of wheat bread but had no impact on aroma of gluten-free breads. Microbial shelf life however, was not prolonged in any of the breads regardless of the starter culture used. Due to the high prevalence of insulin-dependent diabetes mellitus particular amongst coeliac patients, glycaemic control is of great (Berti et al. 2004). The in vitro starch digestibility of gluten-free breads with and without sourdough addition was analysed to predict the GI (pGI). Sourdough can decrease starch hydrolysis in vitro, due to formation of resistant starch and organic acids. Predicted GI of gluten-free control breads were significantly lower than for the reference white wheat bread (GI=100). Starch granule size was investigated with scanning electron microscopy and was significantly smaller in quinoa flour (<2 μm). This resulted in higher enzymatic susceptibility and hence higher pGI for quinoa bread (95). Lowest hydrolysis indexes for sorghum and teff control breads (72 and 74, respectively) correlate with higher gelatinisation peak temperatures (69°C and 71°C, respectively). Levels of resistant starch were not increased by addition of Weissella cibaria MG1 (weak acidifier) or Lactobacillus plantarum FST1.7 (strong acidifier). The pGI was significantly decreased for both wheat sourdough breads (Wc 85; Lp 76). Lactic acid can promote starch interactions with gluten hence decreasing starch susceptibility (Östman et al. 2002). For most gluten-free breads, the pGI was increased upon sourdough addition. Only sorghum and teff Lp sourdough breads (69 and 68, respectively) had significantly decreased pGI. Results suggest that the increase of starch hydrolysis in gluten-free breads was related to mechanism other than presence of organic acids and formation of resistant starch.

Fermento natural de leche: efecto de su empleo sobre la calidad de quesos de leche de oveja

La fabricación de queso es esencialmente un proceso de deshidratación de la leche cuyo resultado final depende del tiempo de coagulación, tipo de fermento y período de maduración. La combinación de estos factores da lugar a una gran variedad de quesos, los que resultan de las diferentes técnicas empleadas en relación a los aspectos mencionados. El fermento es un cultivo de microorganismos cuyo crecimiento en la leche produce ácido láctico a partir de lactosa, acidificando el medio. Además durante la maduración del queso las enzimas bacterianas del inóculo utilizado intervendrán degradando los diferentes componentes de la leche liberando precursores de sustancias responsables de la textura, sabor y aroma del queso. Los fermentos utilizados pueden ser naturales preparados artesanalmente o comerciales seleccionados elaborados industrialmente. Se denominan naturales a aquellos elaborados a partir de la leche ordeñada y cobran especial interés cuando los volúmenes a procesar son pequeños. Su principal ventaja es que permiten aprovechar la ecología zonal bacteriana en la producción de un queso con características particulares, que puede reconocerse por su origen y que presenta características únicas eirrepetibles. El objetivo de este trabajo es evaluar la aptitud quesera de un fermento natural elaborado a partir de la leche de oveja cruza Frisona x Texel proveniente del tambo ovino de la Faculta de Agronomía de la Universidad de Buenos Aires (FAUBA). Para ello se analizaron sólidos totales y características organolépticas de quesos elaborados con fermento natural y se las contrastó con las de quesos elaborados con fermentos seleccionados comerciales. Los resultados del análisis de sólidos totales en quesos no mostraron diferencias significativas entre tratamientos, sin embargo la evaluación sensorial indicó, entre los atributos más destacables, que los quesos elaborados con fermento de leche tuvieron mayor intensidad de olor a oveja, aroma a manteca y leche cocida, sabor más picante y textura más untuosa que los elaborados con fermento comercial. En conclusión estos resultados sugieren que los atributos descriptos dan cuenta de un producto de características sensoriales distintivas. Esto indica la influencia diferencial que tuvo el fermento natural utilizado sobre las características sensoriales de los quesos a través de las enzimas aportadas por las bacterias durante el proceso de maduración.

Volatile flavour components of baked potato flesh. A comparison of eleven potato cultivars

Tubers of eleven cultivars of potato were baked and the flavour compounds from the flesh were isolated by headspace adsorption onto Tenax and analysed by gas chromatography-mass spectrometry (GC-MS). Lipid degradation and the Maillard reaction were the main sources of flavour compounds, accounting for 22-69% and 28-77%, respectively, of the total yields. Various sulfur compounds, methoxypyrazines and terpenes were also identified at lower levels. Relative aroma impact values (RAVs) were calculated by dividing compound yields by the odour threshold value. Compounds contributing most to aroma (RAV > 10000 in at least one cultivar) were 2-isobutyl-3-methoxypyrazine, 2-isopropyl-3-methoxypyrazine, beta -damascenone, dimethyl trisulfide, decanal and 3-methylbutanal. The observed differences in yields and RAVs for compounds among cultivars would be expected to result in differences in perceived flavour.

Volatile compounds in Bacillus-fermented soybeans

Thua nao, a traditional, proteolytic, fermented soybean condiment of northern Thailand, was prepared from cooked whole soybeans by natural flora fermentation. The microbial flora during the fermentation was dominated by Bacillus species. The formation of volatile compounds during the fermentation was studied. In addition, the volatile compounds of two samples of commercial dried thua nao and two samples of commercial Japanese natto were analysed. Fermentation led to a large increase in the concentration of total volatile compounds, from 35 mug kg(-1) wet weight in cooked soybeans to 3500 mug kg(-1) wet weight in 72h fermented material. The major volatile compounds in fermented beans were 3-hydroxybutanone (acetoin), 2-methlybutanoic acid, pyrazines, dimethyl disulphide and 2-pentylfuran. Sun drying of 72 h fermented material resulted in the loss of 65% of total volatiles, including important aroma compounds. The commercial dried thua nao samples had low concentrations of total volatile compounds (380 mug kg(-1) wet weight). It is suggested that improved drying/preservation methods are needed to retain aroma compounds in the traditional products. The natto samples were devoid of aldehydes, aliphatic acids and esters, and sulphur compounds, whereas the thua nao samples contained a diversity of these compounds. Previous investigators have reported these compounds in natto and it is not possible to suggest the existence of systematic differences between the volatile compounds in traditional thua nao prepared with an undefined, mixed microbial flora and those in natto fermented with Bacillus subtilis. (C) 2001 Society of Chemical Industry.

Consumers sensory evaluation of melon sweetness and quality

CONSUMERS SENSORY EVALUATION OF MELON SWEETNESS AND QUALITY Agulheiro Santos, A.C, Rato, A.E., Laranjo, M. and Gonçalves, C. Departamento de Fitotecnia, Escola de Ciências e Tecnologia, Instituto de Ciências Agrárias e Ambientais Mediterrânicas (ICAAM), Instituto de Investigação e Formação Avançada (IIFA), Universidade de Évora, Polo da Mitra, Ap.94, 7002-554 Évora, Portugal. ABSTRACT The sensory quality of fruits is made of a range of attributes like sweetness, acidity, aroma, firmness, color. Taste perception and perception threshold of these attributes are variable according to the psychological and cultural development of individuals. To better understand the quality evaluation of melon by consumers, consumers were invited to taste melon samples, in supermarkets in Évora (South region), Lisbon (Central region) and Vila Nova de Gaia (North region). The present work explored the importance given by consumers to sweetness in order to classify the overall quality of melon. Furthermore, the relationship of the chemical evaluation of Total Soluble Solids (TSS) with sweetness of melon was studied. Fruits from the variety Melão branco picked randomly from those that were exposed for sale in supermarkets were used for analysis. Fruits were chinned along the equatorial zone and only the central part of the fruit, opposite to the part that leaned on the soil, was used to obtain homogeneous samples. Consumers were invited to taste four small pieces of each fruit, previously referenced with a code number, and answer a questionnaire with two questions related to sweetness and overall quality. Each question had five possible levels, identified from “Nothing sweet”, to “Extremely sweet”, in one case, and from “Poor” to “Excellent” in the other. Simultaneously, the values of TSS (measured in ºBrix) for each melon used in the study were evaluated by refractometry. This sensory analysis allowed us to point out the following findings: first of all, there is good agreement between the results obtained to classify “Sweetness” and “Overall Quality” (Cohen’s Kappa=53.1%, p<0.001), which means, for example, that fruits with excellent quality are in general extremely sweet. Moreover, fruits with less than 9.6 °Brix are considered of poor quality and nothing sweet, whereas fruits with values between 10 °Brix and 12 °Brix are considered good in terms of overall quality. It seems that the thresholds for the stimulus/intensity of sweetness lied between 10 °Brix to 14 °Brix for this melon variety. Acknowledgments This work was support by national funds through Fundação para a Ciência e a Tecnologia (FCT) under the Strategic Project Pest-OE/AGR/UI0115/2014 and co-funded by FEDER funds through the COMPETE Program.

Volatile terpenoids and C13 norisoprenoids in wines: development of rapid methods of analysis and evaluation of the sesquiterpenoids biological potential

Vitis vinifera L., the most widely cultivated fruit crop in the world, was the starting point for the development of this PhD thesis. This subject was exploited following on two actual trends: i) the development of rapid, simple, and high sensitive methodologies with minimal sample handling; and ii) the valuation of natural products as a source of compounds with potential health benefits. The target group of compounds under study were the volatile terpenoids (mono and sesquiterpenoids) and C13 norisoprenoids, since they may present biological impact, either from the sensorial point of view, as regards to the wine aroma, or by the beneficial properties for the human health. Two novel methodologies for quantification of C13 norisoprenoids in wines were developed. The first methodology, a rapid method, was based on the headspace solid-phase microextraction combined with gas chromatography-quadrupole mass spectrometry operating at selected ion monitoring mode (HS-SPME/GC-qMS-SIM), using GC conditions that allowed obtaining a C13 norisoprenoid volatile signature. It does not require any pre-treatment of the sample, and the C13 norisoprenoid composition of the wine was evaluated based on the chromatographic profile and specific m/z fragments, without complete chromatographic separation of its components. The second methodology, used as reference method, was based on the HS-SPME/GC-qMS-SIM, allowing the GC conditions for an adequate chromatographic resolution of wine components. For quantification purposes, external calibration curves were constructed with β-ionone, with regression coefficient (r2) of 0.9968 (RSD 12.51 %) and 0.9940 (RSD of 1.08 %) for the rapid method and for the reference method, respectively. Low detection limits (1.57 and 1.10 μg L-1) were observed. These methodologies were applied to seventeen white and red table wines. Two vitispirane isomers (158-1529 L-1) and 1,1,6-trimethyl-1,2-dihydronaphthalene (TDN) (6.42-39.45 μg L-1) were quantified. The data obtained for vitispirane isomers and TDN using the two methods were highly correlated (r2 of 0.9756 and 0.9630, respectively). A rapid methodology for the establishment of the varietal volatile profile of Vitis vinifera L. cv. 'Fernão-Pires' (FP) white wines by headspace solid-phase microextraction combined with comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (HS-SPME/GCxGC-TOFMS) was developed. Monovarietal wines from different harvests, Appellations, and producers were analysed. The study was focused on the volatiles that seem to be significant to the varietal character, such as mono and sesquiterpenic compounds, and C13 norisoprenoids. Two-dimensional chromatographic spaces containing the varietal compounds using the m/z fragments 93, 121, 161, 175 and 204 were established as follows: 1tR = 255-575 s, 2tR = 0,424-1,840 s, for monoterpenoids, 1tR = 555-685 s, 2tR = 0,528-0,856 s, for C13 norisoprenoids, and 1tR = 695-950 s, 2tR = 0,520-0,960 s, for sesquiterpenic compounds. For the three chemical groups under study, from a total of 170 compounds, 45 were determined in all wines, allowing defining the "varietal volatile profile" of FP wine. Among these compounds, 15 were detected for the first time in FP wines. This study proposes a HS-SPME/GCxGC-TOFMS based methodology combined with classification-reference sample to be used for rapid assessment of varietal volatile profile of wines. This approach is very useful to eliminate the majority of the non-terpenic and non-C13 norisoprenic compounds, allowing the definition of a two-dimensional chromatographic space containing these compounds, simplifying the data compared to the original data, and reducing the time of analysis. The presence of sesquiterpenic compounds in Vitis vinifera L. related products, to which are assigned several biological properties, prompted us to investigate the antioxidant, antiproliferative and hepatoprotective activities of some sesquiterpenic compounds. Firstly, the antiradical capacity of trans,trans-farnesol, cis-nerolidol, α-humulene and guaiazulene was evaluated using chemical (DPPH• and hydroxyl radicals) and biological (Caco-2 cells) models. Guaiazulene (IC50= 0.73 mM) was the sesquiterpene with higher scavenger capacity against DPPH•, while trans,trans-farnesol (IC50= 1.81 mM) and cis-nerolidol (IC50= 1.48 mM) were more active towards hydroxyl radicals. All compounds, with the exception of α-humulene, at non-cytotoxic levels (≤ 1 mM), were able to protect Caco-2 cells from oxidative stress induced by tert-butyl hydroperoxide. The activity of the compounds under study was also evaluated as antiproliferative agents. Guaiazulene and cis-nerolidol were able to more effectively arrest the cell cycle in the S-phase than trans,trans-farnesol and α-humulene, being the last almost inactive. The relative hepatoprotection effect of fifteen sesquiterpenic compounds, presenting different chemical structures and commonly found in plants and plant-derived foods and beverages, was assessed. Endogenous lipid peroxidation and induced lipid peroxidation with tert-butyl hydroperoxide were evaluated in liver homogenates from Wistar rats. With the exception of α-humulene, all the sesquiterpenic compounds under study (1 mM) were effective in reducing the malonaldehyde levels in both endogenous and induced lipid peroxidation up to 35% and 70%, respectively. The developed 3D-QSAR models, relating the hepatoprotection activity with molecular properties, showed good fit (R2LOO > 0.819) with good prediction power (Q2 > 0.950 and SDEP < 2%) for both models. A network of effects associated with structural and chemical features of sesquiterpenic compounds such as shape, branching, symmetry, and presence of electronegative fragments, can modulate the hepatoprotective activity observed for these compounds. In conclusion, this study allowed the development of rapid and in-depth methods for the assessment of varietal volatile compounds that might have a positive impact on sensorial and health attributes related to Vitis vinifera L. These approaches can be extended to the analysis of other related food matrices, including grapes and musts, among others. In addition, the results of in vitro assays open a perspective for the promising use of the sesquiterpenic compounds, with similar chemical structures such as those studied in the present work, as antioxidants, hepatoprotective and antiproliferative agents, which meets the current challenges related to diseases of modern civilization.

Sustainable viticulture in Bairrada appellation: vineyard and harvest year effects on grapes oenological potential

The sustainable viticulture of a region passes, among other aspects, for maximizing the varieties potential minimizing subsequent interventions during winemaking, which should contribute to the production of quality wines maintaining their typicity and rationalizing costs. The detailed knowledge of each Appellation specificities, namely vineyard parcel (soil type and topographical peculiarities) and harvest climatic conditions is crucial for sustainability in this sector. Thus, in line with this current trend, the starting point for the development of this PhD thesis was to evaluate the oenological potential of different varieties cultivated throughout Bairrada Appellation (Portugal). During maturation several changes in grape varieties occur, namely berries become sweeter, less acidic, and they develop flavour, aroma and colour properties. The development of these characteristics is essential to define grapes oenological potential, i.e. to estimate the possibility of their usage to produce specific wines. A three years sampling plan was designed to evaluate the effect of harvest year and parcel characteristics on V. vinifera cv. Arinto, Bical, Sauvignon Blanc, Baga, Castelão, Touriga Nacional, and Sousão grapes composition. For each variety, 3 parcels with different characteristics were selected. Several physicochemical parameters were evaluated, during maturation: berry weight, pH, titratable acidity, sugar and phenolic contents, antiradical activity, and volatile composition (free fraction). Special attention was devoted to grapes at technologic maturity, since, besides these parameters, glycosidically-linked fraction was also considered. By using the results obtained at technologic maturity, a comprehensive approach was applied to identify the significance of harvest and parcel characteristics effects on each variety composition. Considering all the parameters under study, it may be highlighted some significant differences. According to the obtained results determined during maturation, it was possible to conclude that Arinto, Bical and Sauvignon Blanc grapes from parcels with clay-sandy and clay-calcareous soils have higher phenolic content and antiradical activity. Otherwise, Sauvignon Blanc presented similar volatile composition for grapes cultivated in the 3 parcels, while Arinto and Bical exhibited higher volatile content in grapes from claysandy and clay-calcareous soils. For Baga, Castelão and Touriga Nacional red varieties, grapes with higher phenolic content, antiradical activity, and volatile content were obtained from clayey and clay-calcareous soils. Furthermore, for Touriga Nacional, parcels altitude seems also to modulate grapes composition. Beyond parcel effect, harvest year conditions also influence grapes composition: 2011 harvest was related with lower phenolic and volatile contents, as well as lower antiradical activity.For grapes collected at technologic maturity, analysis of variance-simultaneous component analysis (ASCA) was applied combining all the parameters under study, in order to assess the influence of harvest and parcel characteristics on each variety oenological potential. The results obtained using this comprehensive approach is closely related with those observed during maturation and revealed that harvest was the main factor that influenced grapes composition (53% to 68% of the total data set variance) followed by parcel characteristics, explaining ca. 15-19% of the total data set variance. The oenological potential of each variety may be different from one parcel to another, i.e., clay-sandy and clay-calcareous related-environments seem to favour Arinto and Bical white grapes composition, but for the red varieties, grapes composition was favoured by clayey and clay-calcareous soils. Besides, also higher altitude seems to favour Touriga Nacional grapes composition. Sauvignon Blanc seems to be a variety well adapted to the different parcel characteristics. In order to go forward in the valuation of these varieties, the aroma properties of 6 monovarietal wines were studied based on an aroma network-approach, linking molecular data related to volatile composition and aroma data about the key odor active molecules. This approach allowed to identify different wine aroma properties and to infer about the consumer’s sensory perception. It was found that aroma properties differ from one wine variety to another: while Arinto and Sauvignon Blanc wine exhibited higher tree fruity, sweety and flowery aromas, related essentially with ester compounds and C13 norisoprenoids, the opposite was obtained for Bical wine, corroborating the aroma sensory perceptions of the trained panel. Sauvignon Blanc also exhibited higher toasted aromas (related with thiols, mainly with 2-methyl-3-furanthiol). Touriga Nacional red wine exhibited higher tree, tropical, and berry fruits notes (sensory described as sweet fruits), toasted and flowery aromas, while these are similar for the other red wines under study. Besides Portuguese Bairrada wines, this aroma network approach is a tool that can be used to explain the aroma properties of wines worldwide. The grape and wine data generated under the present PhD thesis, in the context of Bairrada Appellation, shows the unique character of each variety, and may be used by growers and wine producers as a support for decisionmaking based on objective criteria, increasing the sustainability in this sector. For instance, it is possible to take advantage of the natural resources and produce products with different characteristics obtained from the same variety, minimizing costs during the winemaking process.

O azeite na alimentação humana

O azeite virgem é o sumo resultante da azeitona (fruto da Oliveira, Olea Europea L.) que conserva o sabor, aroma e todas as propriedades do fruto do qual tem origem, pelo que, possui características organolépticas particulares, colocando-o num lugar cimeiro entre as gorduras (Cenzano et al., 1988; March, 1994). É, além disso, a única gordura vegetal que pode ser consumida directamente, virgem e crua (Gonçalves Ferreira, 1994; March, 1994). O seu valor calórico é de 9 Kcal/g, a mesma proporção de qualquer outra gordura, animal ou vegetal (Gonçalves Ferreira, 1994; Peres, 1994).

Início do estudo do envelhecimento da aguardente de medronho

A cor nos destilados indica geralmente um prévio envelhecimento. Os consumidores associam tal facto a um produto de qualidade. Refiram-se os casos dos whiskies e dos brandies. A aguardente de medronho não foge à regra, sendo preferida nos casos em que apresenta cor. No entanto a qualidade deve ser confirmada pelo aroma e sabor, bem como pelas análises químicas. Com efeito, o processo da obtenção da cor nem sempre é o mais adequado. Com o duplo objectivo de estudar o processo mais adequado para obter uma aguardente medronheira velha de qualidade e de a tipificar de modo a identificar eventuais fraudes, a Escola Superior de Tecnologia da Universidade do Algarve (EST-UAlg) em parceria com a Direcção Regional de Agricultura do Algarve (DRAALG) candidataram-se a um projecto PAMAF-IE