Marcelo Ângelo Cirillo

Ochratoxigenic fungi associated with green coffee beans (Coffea arabica L.) in conventional and organic cultivation in Brazil.

The genera Aspergillus comprises species that produce mycotoxins such as aflatoxins, ochratoxins and patulin. These are cosmopolitan species, natural contaminants of agricultural products. In coffee grains, the most important Aspergillus species in terms of the risk of presenting mycotoxins belong to the genera Aspergillus Section Circumdati and Section Nigri. The purpose of this study was to assess the occurrence of isolated ochratoxigenic fungi of coffee grains from organic and conventional cultivation from the South of Minas Gerais, Brazil, as well as to evaluate which farming system presents higher contamination risk by ochratoxin A (OTA) produced by fungi. Thirty samples of coffee grains (Coffea arabica L.) were analysed, being 20 of them of conventional coffee grains and 10 of them organic. The microbiological analysis was done with the Direct Plating Technique in a Dichloran Rose Bengal Chloramphenicol Agar (DRBC) media. The identification was done based on the macro and micro morphological characteristics and on the toxigenic potential with the Plug Agar technique. From the 30 samples analysed, 480 filamentous fungi of the genera Aspergillus of the Circumdati and Nigri Sections were isolated. The ochratoxigenic species identified were: Aspergillus auricoumus, A. ochraceus, A. ostianus, A. niger and A. niger Aggregate. The most frequent species which produces ochratoxin A among the isolated ones was A. ochraceus, corresponding to 89.55%. There was no significant difference regarding the presence of ochratoxigenic A. ochreceus between the conventional and organic cultivation systems, which suggests that the contamination risk is similar for both cultivation systems.

Matrix structure selection in the microparticles of essential oil oregano produced by spray dryer

Abstract The goal of this work was to select the best combination of encapsulants for the microencapsulation of oregano essential oil by spray dryer with the addition of Arabic gum (AG), modified starch (MS) and maltodextrin (MA). The simplex-centroid method was used to obtain an optimal objective function with three variables. Analytical methods for carvacrol quantification, water activity, moisture content, wettability, solubility, encapsulation efficiency (ME) and oil retention (RT) were used to evaluate the best combination of encapsulants. The use of AG as a single wall material increased ME up to 93%. Carvacrol is the major phenolic compound existent in the oregano essential oil. Carvacrol exhibits a maximum concentration of 57.8% in the microparticle with the use of 62.5% AG and 37.5% MA. A greater RT (77.39%) was obtained when 74.5% AG; MS 12.7% and 12.7% MA were applied, and ME (93%) was improved with 100% of gum.

Avaliação da alimentação escolar oferecida aos alunos do ensino fundamental das escolas municipais de Lavras, MG

Objetivou-se no presente estudo avaliar a alimentacao escolar (AE) oferecida aos alunos do ensino fundamental (EF) nas unidades escolares municipais (UEM), urbanas (EU) e rurais (ER), de Lavras, MG, de forma gratuita, em funcao do repasse financeiro do Programa Nacional de Alimentacao Escolar (PNAE), quanto a composicao quimica e atendimento da meta de fornecer 15% das necessidades nutricionais dos alunos. A coleta de amostras para a analise da composicao quimica foi realizada aleatoriamente, em todas as UEM durante o ano de 2004. A analise da AE apresentou valores diarios medios de 189kcal, 7,5g de proteina, 72,9mg de Ca, 16,7mg de Mg, 2,2mg de Fe e 1,4mg de Zn. Para o atendimento da meta de fornecer 15% das necessidades nutricionais, do total de dezesseis escolas estudadas, o teor de energia e calcio encontrava-se abaixo do recomendado em quinze escolas, sendo que apenas uma do meio urbano atendeu a proporcao de energia e uma do meio rural atendeu quanto ao teor de calcio; para o magnesio so tres escolas, duas urbanas e uma rural, atingiram a meta; o oferecimento de proteina e ferro foi atingido por todas as escolas estudadas. Conclui-se que a meta de fornecer 15% das NN na alimentacao escolar nao foi totalmente atingida, pois a maioria das adequacoes ficou fora da faixa recomendada pelo PNAE.

Caracterização física e físico-química de diferentes formulações de doce de goiaba (Psidium guajava L.) da cultivar Pedro Sato

The shelf life of preserves can be extended by the use of preservatives and other combined preservation methods. The objective of the present study was to verify the effects of potassium sorbate and citric acid concentrations and the pulp:sugar ratio on the physical and physicochemical characteristics of guava preserve formulations. A complete 23 factorial design was used with 3 central points. Linear models were fitted to describe the responses as a function of the significant factors. The results showed that the potassium sorbate concentration had little effect on the responses analysed, except for the pH. The pulp/sugar ratio and the citric acid concentration are the most relevant variables to this process. The citric acid concentration and the pulp:sugar ratio must be increased to obtain firm preserves and greater yield.

Data classification with binary response through the Boosting algorithm and logistic regression

Abstract The task of classifying is natural to humans, but there are situations in which a person is not best suited to perform this function, which creates the need for automatic methods of classification. Traditional methods, such as logistic regression, are commonly used in this type of situation, but they lack robustness and accuracy. These methods do not not work very well when the data or when there is noise in the data, situations that are common in expert and intelligent systems. Due to the importance and the increasing complexity of problems of this type, there is a need for methods that provide greater accuracy and interpretability of the results. Among these methods, is Boosting, which operates sequentially by applying a classification algorithm to reweighted versions of the training data set. It was recently shown that Boosting may also be viewed as a method for functional estimation. The purpose of the present study was to compare the logistic regressions estimated by the maximum likelihood model (LRMML) and the logistic regression model estimated using the Boosting algorithm, specifically the Binomial Boosting algorithm (LRMBB), and to select the model with the better fit and discrimination capacity in the situation of presence(absence) of a given property (in this case, binary classification). To illustrate this situation, the example used was to classify the presence (absence) of coronary heart disease (CHD) as a function of various biological variables collected from patients. It is shown in the simulations results based on the strength of the indications that the LRMBB model is more appropriate than the LRMML model for the adjustment of data sets with several covariables and noisy data. The following sections report lower values of the information criteria AIC and BIC for the LRMBB model and that the Hosmer–Lemeshow test exhibits no evidence of a bad fit for the LRMBB model. The LRMBB model also presented a higher AUC, sensitivity, specificity and accuracy and lower values of false positives rates and false negatives rates, making it a model with better discrimination power compared to the LRMML model. Based on these results, the logistic model adjusted via the Binomial Boosting algorithm (LRMBB model) is better suited to describe the problem of binary response, because it provides more accurate information regarding the problem considered.

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.

Characterization of cattle slaughtered at the public abattoir in Lavras-MG

The objective was to characterize cattle slaughtered from the region of Lavras - MG. In the public abattoir 720 bovines were identified and slaughtered from September 20th through November 20th of 2004. Variables such as: genetic origin, live weight, body condition, age, and sex were studied. At arrival, animals were weighed and classified according to their genetic origin. Before slaughter, their body condition (BC) was determined on a 1 - 9 scale. Reproductive status was observed during scratch and evisceration: castrated male, MC; intact male, MI; pregnant female, FG; and Non-pregnant female, FNG. Age was determined by the count of the permanent incisive teeth (p.i.t.). Most animals slaughtered during the survey were male, with predominance of the Girolando genetic group. Overall mean slaughter weight was 438.5 ± 115.97 Kg (n=720). Females (FG and FNG) were older (>48 months old) as compared to male animals, FNG had lower body condition scores (3, 4 and 5). Male (MC and MI), had good body condition scores. Most of slaughtered cattle in Lavras were characterized as non-specialized for beef production.

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.

Uso de alguns estimadores ridge na análise estatística de experimentos em entomologia

Inumeros experimentos em ciencias agrarias apresentam variaveis que podem dar origem a problemas de multicolinearidade. Em se tratando da aplicabilidade de modelos de regressao, o problema da multicolinearidade tem como principal consequencia o inflacionamento dos erros padrao e, com isso, o valor da estatistica t-student e reduzido de tal forma que interfere nos resultados inferenciais. Varias medidas sao propostas, na literatura, para resolver o problema de multicolinearidade. Entretanto, o desempenho dessas medidas esta sujeito ao grau de multicolinearidade que as variaveis poderao apresentar, bem como ao tamanho amostral. Frente a este problema, este trabalho tem por objetivo avaliar alguns estimadores ridge, utilizando simulacao Monte Carlo, bem como, apresentar a aplicacao desses estimadores em um experimento, com dados reais, na area de entomologia. Mediante esta aplicacao, os resultados expressivos alcancados foram obtidos em funcao da eficiencia dos estimadores ridge avaliados, em relacao ao estimador de minimos quadrados. Em se tratando dos resultados computacionais, concluiu-se que estimadores ridge avaliados sao recomendaveis, em experimentos que considerem as variaveis com diferentes graus de multicolinearidade, para amostras maiores do que n=50.

Diversity and association of filamentous fungi in coffee beans under organic and conventional cultivation

Brazil is a country with great biodiversity; however, knowledge of this microbiological wealth is currently insufficient for its utilization in a sustainable manner. Agricultural expansion represents one of the largest current dangers to biodiversity and threatens to cause the extinction of a variety of species. This study therefore aimed to isolate and identify the species of fungi present in coffee beans cultivated in organic and conventional systems. Eighteen (18) samples of coffee beans from southern Minas Gerais were analyzed, and 346 fungal isolates were obtained from the analyzed coffee beans. These isolates belonged to 32 species in the following 14 genera: Aspergillus, Penicillium, Fusarium, Cladosporium, Mucor, Rhizopus, Trichoderma, Epicoccum, Phoma, Bipolaris, Glomerella, Colletotrichum, Alternaria and Gliocladium. Organic coffee bean samples exhibited the highest indices of fungal diversity. Two species identified in this study, Aspergillus flavus and Aspergillus ochraceus, are extremely important for their toxigenic characteristics. We utilized simple correspondence analysis to evaluate the interaction of the identified fungi with the toxigenic species. An association of toxigenic fungi with other fungi is important because some microorganisms can degrade mycotoxins. In the organic coffee beans, A. flavus was associated with Cladosporium cladosporioides, A. ochraceus, and Penicillium brevicompactum. In contrast, in the conventional coffee beans, A. ochraceus was only associated with C. cladosporioides. These results demonstrate that greater fungal diversity exists in organic coffee beans. Key words: Interactions, microorganisms, mycotoxins, Aspergillus.