59 research outputs found

    Primary amino acid composition and its use in discrimination of Greek red wines with regard to variety and cultivation region

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    The primary amino acid content of 54 Greek red wines from several regions and grape varieties was determined by reversed-phase high performance liquid chromatography (HPLC) using precolumn derivatization with OPA (o-phthalaldehyde) and fluorescence detection. For each wine sample, 21 amino acids have been determined. Wine samples from the 4 most common Greek red grape cultivars, which are part of the Greek VQPRD (Vins de Qualité Produits dans des Regions Délimitees) wines, and from 4 foreign red grape varieties, were used. Wines from cv. Kotsifali had the highest amino acid content among the samples from indigenous varieties, followed by those originating from cvs Agiorgitiko, Mandilaria and Xinomavro. In contrast to wines from cv. Grenache rouge, which contained high amounts of amino acids, those from Cabernet Sauvignon, Syrah and Merlot had lower amounts. A classification of samples on the basis of variety and region was achieved by application of the discriminant analysis of the amino acid composition data. 22 % of the wine samples, originating from grapes cultivated in 'organic vineyards', had a low arginine content.

    Evaluation d'une méthode CLHP adaptée au dosage des acides aminés du vin

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    Afin de rechercher I' origine des amines biogènes, nous avons dosé les acides aminés d'un grand nombre d'échantillons de vin. Une méthode de CLHP utilisant la détection par fluorimétrie des dérivés o-phtaldialdéhyde (OPA) a été adaptée pour séparer spécifiquement les acides aminés, précurseurs des amines biogénes. La séparation a été effectuée à l'aide de deux colonnes en série de type phase inverse C18 Lichrospher 100 RP18. Cette méthode permet l'analyse de 16 échantillons par 24 h à l'aide d'un passeur/préparateur automatique. Son évaluation montre qu'elle présente une linéarite satisfaisante et que sa répetabilité est excellente (CV=2,29 à 7,25 %). La variabilité intralaboratoire montre qu'il existe peu d'écart parmi les analyses effectuées dans les différents jours.HPLC method adapted for the determination of amino acids in wineTo investigate the origin of biogenic amines, we have determined the amino acid content of a large number of wine samples. An HPLC method with fluorescence detection of OPA derivatives was adapted to separate specifically the amino acids which are the precursors of biogenic amines. The separation was effected by means of two columns of Lichrosphere 100 RP18. This method allows the analysis of 16 samples per 24 h, by means of an autosampler, and shows a satisfactory linearity and an excellent repeatability (CV = 2.29 to 7.25 %). The intralaboratory variability was judged to be satisfactory; the deviation between the results, obtained on different days of the analysis of the same sample, was small

    Survival of Lactobacillus sakei during heating, drying and storage in the dried state when growth has occurred in the presence of sucrose or monosodium glutamate

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    Spray-dried cells of Lactobacillus sakei CTC 494 survived ca. 60% longer in the spray dried state when cells were grown in the presence of 20 g sucrose l)1 or 12.5 g monosodium glutamate l)1. No significant differences were observed in viability during storage in the freeze dried state with the addition of these compounds to the growth medium, nor in survival during a heat treatment (55ºC). Both sucrose and glutamate in the growth medium suppressed intracellular accumulation of total amino acids and changed the overall pattern of the individual amino acids. Glutamate in the growth medium enhanced intracellular glutamate by ca. 38

    Relationship Between Biogenic Amines and Free Amino Acid Contents of Winesand Musts from Alentejo (Portugal)

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    The concentration of biogenic amines and free amino acids was studied in 102 Portuguese wines and 18 musts from Alentejo demarcated (D.O.C.) regions. Most wines were commercial, except for 38 monovarietals obtained by micro vinification. Musts from the varieties used to produce the latter wines were also studied. Both biogenic amines and free amino acids were analyzed by HPLC using fluorescence detection for their o-phthalaldehyde/fluorenylmethyl chloroformate (OPA/FMOC) derivatives. The most significant amines (average 10.8 mg/L for histamine+tyramine in red, and 7.4 mg/L for white wines) were found to be present at low levels and, although no important relationship between each individual biogenic amine could be obtained, the total amine content depends significantly on the assimilable amino acid content in wine

    Effects of Microwave Heating on Sensory Characteristics of Kiwifruit Puree

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    The effect of microwave processing on the characteristics of kiwifruit puree was evaluated by applying various gentle treatments. Different combinations of microwave power/processing time were applied, with power among 200-1,000 W and time among 60-340 s, and various sensory and instrumental measurements were performed with the aim of establishing correlations and determining which instrumental parameters were the most appropriate to control the quality of kiwi puree. The water and soluble solids of the product, 83 and 14/100 g sample, respectively, did not change due to treatments. For sensory assessment, an expert panel was previously trained to describe the product. Fourteen descriptors were defined, but only the descriptors 'typical kiwifruit colour', 'tone', 'lightness', 'visual consistency' and 'typical taste' were significant to distinguish between kiwifruit puree samples. The instrumental analysis of samples consisted in measuring consistency, viscosity, colour and physicochemical characteristics of the treated and fresh puree. Applying intense treatments (600 W-340 s, 900 W-300 s and 1,000 W-200 s) through high power or long treatment periods or a combination of these factors, mainly affects the consistency (flow distance decreased from 5. 9 to 3. 4 mm/g sample), viscosity (increased from 1. 6 to 2. 5 Pa/s), colour (maximun ¿E was 6 U) and taste of the product. As a result, samples were thicker and with an atypical flavour and kiwifruit colour due to increased clarity (L* increased from 38 to 43) and slight changes in the yellow-green hue (h* decreased from 95 to 94). For the instrumental determinations of colour and visual perception of consistency, the most suitable parameters for quality control are the colour coordinates L*, a*, h*, whiteness index and flow distance measured with a Bostwick consistometer. © 2011 Springer Science+Business Media, LLC.The authors thank the Ministerio de Educacion y Ciencia for the financial support given throughout the Project AGL 2010-22176. The authors are indebted to the Generalitat Valenciana (Valencia, Spain) for the Grant awarded to the author Maria Benlloch. The translation of this paper was funded by the Universidad Politecnica de Valencia, Spain.Benlloch Tinoco, M.; Varela Tomasco, PA.; Salvador Alcaraz, A.; Martínez Navarrete, N. (2012). Effects of Microwave Heating on Sensory Characteristics of Kiwifruit Puree. Food and Bioprocess Technology. 5(8):3021-3031. https://doi.org/10.1007/s11947-011-0652-1S3021303158Albert, A., Varela, P., Salvador, A., & Fiszman, S. M. (2009). Improvement of crunchiness of battered fish nuggets. European Food Research and Technology, 228, 923–930.Alegria, P., Pinheiro, J., Gonçalves, E. M., Fernandes, I., Moldao, M., & Abreu, M. (2010). Evaluation of a pre-cut heat treatment as an alternative to chlorine in minimally processed shredded carrot. Innovative Food Science and Emerging Technologies, 11, 155–161.AOAC. (2000). Official Methods of Analysis of AOAC International. Gaithersburg: AOAC.Barboni, T., Cannac, M., & Chiaramonti, N. (2010). Effect of cold storage and ozone treatment on physicochemical parameters, soluble sugars and organic acids in Actinidia deliciosa. Food Chemistry, 121, 946–951.Beirão-da-Costa, S., Steiner, A., Correia, L., Empis, J., & Moldão-Martins, M. (2006). Effects of maturity stage and mild heat treatments on quality of minimally processed kiwifruitfruit. Journal of Food Engineering, 76, 616–625.Bodart, M., de Peñaranda, R., Deneyer, A., & Flamant, G. (2008). Photometry and colorimetry characterisation of materials in daylighting evaluation tools. Building and Environment, 43, 2046–2058.Bourne, M. C. (1982). Food texture and viscosity-concept and measurement. New York: Academic.Cano, M. P., Hernández, A., & de Ancos, B. (1997). High pressure and temperature effects on enzyme inactivation in strawberry and orange products. Journal of Food Science, 62(1), 85–88.Chiralt, A., Martínez-Navarrete, N., Camacho, M. M., & González, C. (1998). Experimentos de fisicoquímica de alimentos. Valencia: Editorial Universidad Politécnica de Valencia (Chapter 3).Chiralt, A., Martínez-Navarrete, N., González, C., Talens, P., & Moraga, G. (2007). Propiedades físicas de los alimentos. Valencia: Editorial Universidad Politécnica de Valencia (Chapter 16).Contreras, C., Martín, M. E., Martínez-Navarrete, N., & Chiralt, A. (2005). Effect of vacuum impregnation and microwave application on structural changes occurred during air drying of apple. Food Science and Technology/LWT, 38(5), 471–477.Contreras, C., Martín-Esparza, M. E., Martínez-Navarrete, N., & Chiralt, A. (2007). Influence of osmotic pre-treatment and microwave application on properties of air dried strawberry related to structural changes. European Food Research and Technology, 224, 499–504.de Ancos, B., Cano, M. P., Hernández, A., & Monreal, M. (1999). Effects of microwave heating on pigment composition and color of fruit purees. Journal of the Science of Food and Agriculture, 79, 663–670.Dubost, N. J., Shewfelt, R. L., & Eitenmiller, R. R. (2003). Consumer acceptability, sensory and instrumental analysis of peanut soy spreads. Journal of Food Quality, 26, 27–42.Escribano, S., Sánchez, F. J., & Lázaro, A. (2010). Establishment of a sensory characterization protocol for melon (Cucumis melo L.) and its correlation with physical-chemical attributes: indications for future genetics improvements. European Food Research and Technology, 231, 611–621.Fang, L., Jiang, B., & Zhang, T. (2008). Effect of combined high pressure and thermal treatment in kiwifruit peroxidase. Food Chemistry, 109, 802–807.Fisk, C. L., McDaniel, M. R., Strick, B. C., & Zhao, Y. (2006). Physicochemical, sensory, and nutritive qualities of hardy kiwifruit (Actinidia arguta ‘Ananasnaya’) as affected by harvest maturity and storage. Sensory and Nutritive Qualities of Food, 71(3), 204–210.Fúster, C., Préstamo, G., & Cano, M. P. (1994). Drip loss, peroxidase and sensory changes in kiwi fruit slices during frozen storage. Journal of the Science of Food and Agriculture, 64, 23–29.Guldas, M. (2003). Peeling and the physical and chemical properties of kiwi fruit. Journal of Food Processing Preservation, 27, 271–284.Igual, M., Contreras, C., & Martínez-Navarrete, N. (2010). Non-conventional techniques to obtain grapefruit jam. Innovative Food Science and Emerging Technologies, 11, 335–341.Igual, M., García-Martínez, E., Camacho, M. M., & Martínez-Navarrete, N. (2010). Effect of thermal treatment and storage on the stability of organic acids and the functional value of grapefruit juice. Food Chemistry, 118, 291–299.Jaeger, S. R., Rossiter, K. L., Wismer, W. V., & Harker, F. R. (2003). Consumer-driven product development in the kiwifruit industry. Food Quality and Preference, 14, 187–198.Lawless, H., & Heymann, H. (1998). Sensory evaluation of food: Principles and practices. New York: Chapman & Hall.MAPA (2010). Plataforma de conocimiento para el medio rural y pesquero. National Agricultural Statistics Database, Spain, Available at: www.mapa.es . Accessed 05 October 2010.Maskan, M. (2001). Kinetics of colour change of kiwifruits during hot air and microwave drying. Journal of Food Engineering, 48, 169–175.Mohammadi, A., Rafiee, S., Emam-Djomeh, Z., & Keyhani, A. (2008). Kinetic models for colour change in kiwifruit slices during Hoy Air drying. World Journal of Agricultural Sciences, 4(3), 376–383.Moretti, C. L., Mattos, L. M., Machado, C. M. M., & Kluge, R. A. (2007). Physiological and quality attributes associated with different centrifugation times of baby carrots. Horticultura Brasileira, 25, 557–561.Nielsen, S. S. (2010). Food analysis laboratory manual. New York: Springer.Oraguzie, N., Alspach, P., Volz, R., Whitworz, C., Ranatunga, C., Weskett, R., et al. (2009). Postharvest assessment of fruit quality parameters in apple using both instrument and an expert panel. Posthaverst Biology and Technology., 52, 279–287.Pagliarini, E., Laureati, M., & Lavelli, V. (2010). Sensory evaluation of gluten-free breads assessed by a trained panel of celiac assessors. European Food Research and Technology, 231, 37–46.Park, E. Y., & Luh, B. S. (1985). Polyphenol oxidase of kiwifruit. Journal of Food Science, 50, 678–684.Schubert, H., & Regier, M. (2010). The microwave processing of foods. London: Woodhead.Segnini, S., Dejmek, P., & Öste, R. (1999). Relationship between instrumental and sensory analysis of texture and colour of potato chips. Journal of Texture Studies, 30, 677–690.Sinija, V. R., & Mishra, H. N. (2011). Fuzzy analysis of sensory data for quality evaluation and ranking of instant green Tea powder and granules. Food Bioprocess Technology, 4, 408–416.Soufleros, E. H., Pissa, I., Petridis, D., Lygerakis, M., Mermelas, K., Boukouvalas, G., et al. (2001). Instrumental analysis of volatile and other compounds of Greek kiwi wine; sensory evaluation and optimization of its composition. Analytical, Nutritional and Clinical Methods Section, 75, 487–500.Vadivambal, R., & Jayas, D. S. (2007). Changes in quality of microwave-treated agricultural products-a review. Biosystems Engineering, 98, 1–16.Worch, T., Lê, S., & Punter, P. (2010). How reliable are the consumers? Comparison of sensory profiles from consumers and experts. Food Quality and Preference, 21, 309–318.Zanoni, B., Lavelli, V., Ambrosoli, R., Garavaglia, L., Minati, J., & Pagliarini, E. (2007). A model to predict shelf-life in air and darkness of cut, ready-to-use, fresh carrots under both isothermal and non-isothermal conditions. Journal of Food Engineering, 79, 586–591.Zolfaghari, M., Sahari, M. A., Barzegar, M., & Samadloiy, H. (2010). Physicochemical and enzymatic properties of five kiwifruit cultivars during cold storage. Food Bioprocess Technology, 3, 239–246
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