Diego Egídio Ribeiro

Discrimination of the sensory quality of the Coffea arabica L. (cv. Yellow Bourbon) produced in different altitudes using decision trees obtained by the CHAID method.

BACKGROUND Knowledge of the sensory profile of coffee quality, associated with genetic and environmental factors, is of utmost importance for the international market, as well as for the productive sector. In this context, the goal of this study was to classify the quality of Coffea arabica L., cv. Yellow Bourbon, according to different scores obtained through sensory evaluations based on the Specialty Coffee Association of America protocol (SCAA), and by means of decision trees resulting from applying the CHAID method (chi-square automatic interaction detection). To that end, we used a database with the sensory characteristics of cv. Yellow Bourbon and the environmental characteristics of the Mantiqueira de Minas region, State of Minas Gerais, Brazil. RESULTS The method used exhibited promising results regarding accuracy and success rates in order to discriminate coffee sensory quality as a function of the production environment. The results obtained clearly show the effect of the coffee growing environment on the Yellow Bourbon variety, resulting in notable sensory differences in the beverage. CONCLUSION It was possible to discriminate cv. Yellow Bourbon coffee samples, the sensory evaluations of which resulted in scores of ≥88 points, which are associated with growing environments at altitudes of ≥1200 m.

Seedling survival of Handroanthus impetiginosus (Mart ex DC) Mattos in a semi-arid environment through modified germination speed and post-germination desiccation tolerance.

Uniform rapid seed germination generally forms a great risk for the plant population if subsequent intermittent precipitation causes desiccation and seedling death. Handroanthus impetiginosus can be found commonly in a wide range of biomes within Brazil including those that are semi-arid. Germination and early growth was studied to understand how germinated seeds survive under these stringent conditions. Accessions were sampled from four seasonally dry biomes in Brazil. Precipitation at the start of the rainy season in the Caatinga, a semi-arid biome, is less predictable and the number of successive dry days per dry interval in the first four months of the rainy season was higher than in the other studied biomes. Plants from the Caatinga produced thicker seeds and this trait concurred with slow germination and stronger osmotic inhibition of germination across the accessions, forming a stress avoidance mechanism in the Caatinga. Post-germination desiccation tolerance was high in the Caatinga accession, could be re-induced in accessions from biomes with more regular precipitation (Cerrado and transition zone), but remained poor in the Cerradão accession; thus forming a stress tolerance mechanism. Production of adventitious roots ascertained survival of all tested individuals from all four locations, even if protruded radicles did not survive desiccation, forming an additional stress tolerance mechanism. A sequence of stress avoidance and stress tolerance mechanisms in seeds and germinated seeds was associated with precipitation patterns in different biomes. These mechanisms purportedly allow rapid seedling establishment when conditions are suitable and enable survival of the young seedling when conditions are adverse.

Selecting A Probabilistic Model Applied To The Sensory Analysis Of Specialty Coffees Performed With Consumer

Sensory analysis of cafes assumes that a sensory panel is formed by trained panelists according to recommendations of the American Specialty Coffee Association. However, the choice that determines the preference of a coffee is routinely done through experimentation with consumers, in which largely presents no particular skill in terms of sensory characteristics. Upon this fact, this study aimed to conduct a study considering several probabilistic distributions belonging to the class of generalized extreme value, considering a sensory analysis applied to evaluation of four specialty coffees produced with different processes and at different altitudes in the mountain region of the Mantiqueira state of Minas Gerais. For this analysis, we considered a sensory panel trained to untrained consumers. It was found that the extreme value distribution was the best fit and the final note that the odds of a consumer to submit a maximum score was 9.0 points lower. Therefore, there is evidence to conclude that an efficient identification of specialty coffees produced in this region made by consumers requires more intensive training.

Qualidade de cafés especiais: uma avaliação sensorial feita com consumidores utilizando a técnica MFACT

A qualidade sensorial de cafes especiais, cujas caracteristicas se relacionam com o meio geografico e apreciada pelo setor produtivo e o mercado, no qual, uma relacao comercial e pautada na livre escolha, por parte do consumidor e na agregacao de valores e diferenciacao de precos em funcao da qualidade do produto. Neste cenario, focar as tendencias dos consumidores e primordial para que um cafe seja diferenciado em relacao aos demais; para isso, novas metodologias de analise devem ser exploradas para que os resultados sejam dignos de contemplaram inumeros fatores inerentes as particularidades de cada consumidor e/ou produto. Com esse proposito, o objetivo desse artigo e propor o uso da tecnica de multiplos fatores aplicada a tabelas de contingencia (MFACT), em dados categorizados obtidos em um experimento sensorial realizado com diferentes grupos de consumidores com a finalidade de identificar similaridades entre quatro cafes especiais. Concluiu-se que o uso dessa tecnica e viavel, por permitir discriminar os cafes especiais produzidos em diferentes ambientes (altitudes) e processamentos, considerando a heterogeneidade entre os consumidores envolvidos na analise sensorial.

REINDUCTION OF DESICCATION TOLERANCE IN SEEDS OF Bauhinia forficata LINK (FABACEAE).

Bauhinia forficata Link e uma especie arborea de interesse medicinal e agronomico. Devido a importância da especie objetivou-se avaliar caracteristicas da germinacao de B. forficata, bem como a capacidade desta especie em manter a tolerância a dessecacao apos a germinacao. Os resultados indicam B. forficata como uma especie com capacidade de reinducao de tolerância a dessecacao. Atraves de eletromicrografias de varredura foi possivel entender os efeitos positivos de uma secagem lenta em sementes germinadas. Conclui-se entao que B. forficata possui capacidade de re-inducao de tolerancia a dessecacao com ate 4mm de comprimento de radicula, quando tratada com solucao de PEG a -1,4MPa.Dissertacao apresentada a Universidade Federal de Lavras, como parte das exigencias do Programa de Pos-Graduacao em Agronomia, area de concentracao em Fisiologia Vegetal, para obtencao do titulo de Mestre.