Standard Analytical Methods, Sensory Evaluation, NIRS and Electronic Tongue for Sensing Taste Attributes of Different Melon Varieties

Grafting by vegetables is a practice with many benefits, but also with some unknown influences on the chemical composition of the fruits. Our goal was to assess the effects of grafting and storage on the extracted juice of four orange-fleshed Cantaloupe type (Celestial, Donatello, Centro, Jannet) melons and two green-fleshed Galia types (Aikido, London), using sensory profile analysis and analytical instruments: An electronic tongue (E-tongue) and near-infrared spectroscopy (NIRS). Both instruments are known for rapid qualitative and quantitative food analysis. Linear discriminant analysis (LDA) was used to classify melons according to their varieties and storage conditions. Partial least square regression (PLSR) was used to predict sensory and standard analytical parameters. Celestial variety had the highest intensity for sensory attributes in Cantaloupe variety. Both green and orange-fleshed melons were discriminated and predicted in LDA with high accuracies (100%) using the E-tongue and NIRS. Galia and Cantaloupe inter-varietal classification with the E-tongue was 89.9% and 82.33%, respectively. NIRS inter-varietal classification was 100% with Celestial variety being the most discriminated as with the sensory results. Both instruments, classified different storage conditions of melons (grafted and self-rooted) with high accuracies. PLSR showed high accuracy for some standard analytical parameters, where significant differences were found comparing different varieties in ANOVA

Electronic tongue technology applied to the analysis of grapes and wines

El desarrollo de nuevos métodos de análisis para caracterizar los alimentos es de vital importancia para mejorar los actuales sistemas de control de calidad de los productos alimenticios. Dentro de este campo, el concepto de lengua electrónica (ETs o e-tongues) ha crecido rápidamente en los últimos años debido a su gran potencial. Estos dispositivos se basan en sensores electroquímicos combinados con análisis de datos multivariantes. De acuerdo con la IUPAC (Unión Internacional de Química Pura y Aplicada), una lengua electrónica es un sistema multisensor, que consiste en un número de sensores de baja selectividad y utiliza procedimientos matemáticos avanzados para el procesamiento de señales basados en el reconocimiento de patrones (PARC) y/o análisis multivariante [redes neuronales artificiales (RNA), análisis de componentes principales (PCA), etc.]. Por lo tanto, las ETs son sistemas holísticos que proporcionan información global y cualitativa acerca de la muestra en lugar de datos cuantitativos acerca de compuestos específicos. Sin embargo, si la matriz de datos obtenida por estos sistemas se analiza con herramientas de procesamiento quimiométrico adecuadas, se podría extraer información descriptiva o predictiva de parámetros específicos. Existe un término más reciente en el campo de las lenguas electrónicas, ampliamente denominado lengua bioelectrónica (bioET), que incluye el uso de uno o varios biosensores implementados en las ETs. Durante esta investigación se han aplicado ETs y bioETs para estudiar las uvas tintas y los vinos con el fin de predecir mejor el momento óptimo de la vendimia de uvas, así como los parámetros de calidad de interés en los vinos.Departamento de Química Física y Química InorgánicaDoctorado en Físic

Quantificação de açúcares com uma língua eletrónica: calibração multivariada com seleção de sensores

Mestrado com dupla diplomação com a Universidade Tecnológica Federal do ParanáEste trabalho incide na análise dos açúcares majoritários nos alimentos (glucose, frutose e sacarose) com uma língua eletrónica potenciométrica através de calibração multivariada com seleção de sensores. A análise destes compostos permite contribuir para a avaliação do impacto dos açúcares na saúde e seu efeito fisiológico, além de permitir relacionar atributos sensoriais e atuar no controlo de qualidade e autenticidade dos alimentos. Embora existam diversas metodologias analíticas usadas rotineiramente na identificação e quantificação dos açúcares nos alimentos, em geral, estes métodos apresentam diversas desvantagens, tais como lentidão das análises, consumo elevado de reagentes químicos e necessidade de pré-tratamentos destrutivos das amostras. Por isso se decidiu aplicar uma língua eletrónica potenciométrica, construída com sensores poliméricos selecionados considerando as sensibilidades aos açucares obtidas em trabalhos anteriores, na análise dos açúcares nos alimentos, visando estabelecer uma metodologia analítica e procedimentos matemáticos para quantificação destes compostos. Para este propósito foram realizadas análises em soluções padrão de misturas ternárias dos açúcares em diferentes níveis de concentração e em soluções de dissoluções de amostras de mel, que foram previamente analisadas em HPLC para se determinar as concentrações de referência dos açúcares. Foi então feita uma análise exploratória dos dados visando-se remover sensores ou observações discordantes através da realização de uma análise de componentes principais. Em seguida, foram construídos modelos de regressão linear múltipla com seleção de variáveis usando o algoritmo stepwise e foi verificado que embora fosse possível estabelecer uma boa relação entre as respostas dos sensores e as concentrações dos açúcares, os modelos não apresentavam desempenho de previsão satisfatório em dados de grupo de teste. Dessa forma, visando contornar este problema, novas abordagens foram testadas através da construção e otimização dos parâmetros de um algoritmo genético para seleção de variáveis que pudesse ser aplicado às diversas ferramentas de regressão, entre elas a regressão pelo método dos mínimos quadrados parciais. Foram obtidos bons resultados de previsão para os modelos obtidos com o método dos mínimos quadrados parciais aliado ao algoritmo genético, tanto para as soluções padrão quanto para as soluções de mel, com R²ajustado acima de 0,99 e RMSE inferior a 0,5 obtidos da relação linear entre os valores previstos e experimentais usando dados dos grupos de teste. O sistema de multi-sensores construído se mostrou uma ferramenta adequada para a análise dos iii açúcares, quando presentes em concentrações maioritárias, e alternativa a métodos instrumentais de referência, como o HPLC, por reduzir o tempo da análise e o valor monetário da análise, bem como, ter um preparo mínimo das amostras e eliminar produtos finais poluentes.This work focuses on the analysis of the major sugars in foods (glucose, fructose and sucrose) with a potentiometric electronic tongue through multivariate calibration with sensors subset selection. The analysis of these compounds contributes to the assessment of the impact of sugars on health and its physiological effect; also, allows to relate sensory attributes and act on quality control and authenticity of the food. Although there are various analytical methods routinely used in the identification and quantification of sugars in foods, in general these methods have several disadvantages such as, slowness of the analysis, high consumption of chemicals and the need for destructive pretreatments of samples. Therefore, it was decided to apply a potentiometric electronic tongue, built with polymeric sensors selected considering the sensitivities to sugar obtained in previous studies, on the analysis of sugars in foods aiming to establish an analytical methodology and mathematical procedures to quantify these compounds. For this purpose, standard solutions of ternary mixtures of sugars and solutions of honey (previously analyzed by HPLC to determine the reference concentrations of sugars) at different levels of concentration were analysed. Hence, an exploratory data analysis aiming to remove sensors or discordant observations was made by performing a principal component analysis. Then multiple linear regression models were built with variable selection by using the stepwise algorithm and it was found that although it was possible to establish a good relation between the sensors responses and the sugars concentrations, the models did not show satisfactory predictive performance in test group data. Thus, in order to overcome this problem, new approaches were tested through the construction and optimization of the parameters of a genetic algorithm for selection of variables that could be applied to various regression techniques, including the regression with the method of partial least squares. Good predictive results were obtained for the partial least squares models combined with genetic algorithm for both standard solutions and for honey solutions, with values of R²ajusted above 0.99 and RMSE less than 0.5, obtained from the linear relationship between the predicted and experimental values using data of test groups. The multisensor system built proved to be a suitable tool for the analysis of sugars, when present in majority concentrations, and an alternative to analytical instrumental methods of reference, such as HPLC, by reducing the time of analysis and its monetary value, as well as, having a minimal sample preparation and eliminate pollutants

Little Village December, 2012

https://ir.uiowa.edu/littlevillage/1122/thumbnail.jp

Crossroads of Cuisine

Crossroads of Cuisine provides a history of foods, and foodways in terms of exchanges taking place in Central Asia and in surrounding areas such as China, Korea or Iran during the last 5000 years, stressing the manner in which East and West, West and East grew together through food. It provides a discussion of geographical foundations, and an interlocking historical and cultural overview going down to the present day, with a comparative country by country survey of foods and recipes. An ethnographic photo essay embracing all parts of the book binds it all together, and helps make topics discussed vivid and approachable. The book is important for explaining key relationships that have not always been made clear in past scholarship

Food science sourcebook

2 v. : ill. ; 26 cm2nd edition.Rev. ed. of: Source book for food scientists. c1978"An AVI book."Pt. 1. Terms and descriptions -- pt. 2. Food composition,properties, and general data

Novel Analysis on Aroma Compounds of Wine, Vinegar and Derived Products

Aroma compounds are some of the main compounds responsible for the acceptance of oenological products such as wine, vinegar and derived products. These kinds of compounds are produced during the winemaking process and they can be affected by natural, geographical and human factors: raw material, alcoholic and acetic fermentation, ageing, distillation, technological processes, etc. Therefore, it is very important to study and to characterize the aromatic fraction of these oenological beverages in order to improve the quality of the final product. Therefore, this book is focused on some recent studies related to the study of the volatile composition of wine, vinegar and derived products, in many different fields of science: oenology, chemistry, food science and technology, biochemistry, microbiology, biotechnology, engineering, sensory analysis, etc., and it shows the great importance of both sensory and analytical study of oenological products aroma and how they are influenced by the different stages and conditions under which they are elaborated. In this book, you will find 12 valuable scientific contributions: 2 literature reviews and 10 original research works, which deal with the latest advances in both sensory and analytical tools in order to evaluate the effects of different techniques or winemaking stages on the oenological products’ aromas

Routledge Handbook of Chinese Medicine

The Routledge Handbook of Chinese Medicine is an extensive, interdisciplinary guide to the nature of traditional medicine and healing in the Chinese cultural region, and its plural epistemologies. Established experts and the next generation of scholars interpret the ways in which Chinese medicine has been understood and portrayed from the beginning of the empire (third century BCE) to the globalisation of Chinese products and practices in the present day, taking in subjects from ancient medical writings to therapeutic movement, to talismans for healing and traditional medicines that have inspired global solutions to contemporary epidemics. The volume is divided into seven parts: Longue Durée and Formation of Institutions and Traditions Sickness and Healing Food and Sex Spiritual and Orthodox Religious Practices The World of Sinographic Medicine Wider Diasporas Negotiating Modernity This handbook therefore introduces the broad range of ideas and techniques that comprise pre-modern medicine in China, and the historiographical and ethnographic approaches that have illuminated them. It will prove a useful resource to students and scholars of Chinese studies, and the history of medicine and anthropology. It will also be of interest to practitioners, patients and specialists wishing to refresh their knowledge with the latest developments in the field. The Open Access version of this book, available at http://www.taylorfrancis.com, has been made available under a Creative Commons Attribution-Non Commercial-No Derivatives 4.0 licens