Análises de matérias estranhas e microbiológicas de chás industrializados comercializados em Pouso Alegre MG / Analysis of extraneous materials and microbiological from industrialized teas marketed in Pouso Alegre MG

O objetivo deste estudo foi de avaliar as condições higiênico-sanitárias de quatro marcas de chás industrializados comercializados na cidade de Pouso Alegre - MG utilizando parâmetros de presença de matérias estranhas e análises microbiológicas. Foram coletadas no período de setembro a outubro de 2017, amostras de chás de camomila, erva-doce, hortelã e chá misto que contém em sua formulação essas mesmas ervas. Foram utilizados os métodos da Association of Official Analytical Chemists International (AOAC) de acordo com a RDC n°14 para capturar as sujidades leves e nas análises microbiológicas, foram utilizados métodos da International Organization for Standardization (ISO) de acordo com a RDC n° 12 para avaliar coliformes totais e termotolerantes, fungos e Salmonella spp. Nas pesquisas de matérias estranhas somente três marcas de camomila foram aprovadas, estando o restante dos chás em desacordo com a legislação vigente por estarem acima do limite de tolerância aceitável. Na avaliação de coliformes e Salmonella sp. todas as amostras foram aprovadas porém, houve um crescimento considerável de fungos filamentosos nestas amostras...

The aim of this study was to evaluate the hygienic-sanitary conditions of four brands of industrialized teas marketed in the city of Pouso Alegre - MG using parameters of presence of foreign matter and microbiological analyzes. Were collected in the period from September to October 2017, samples of chamomile teas, fennel, mint and mixed tea that contains in its formulation these same herbs. Were used the methods of the International Association of Analytical Chemists (AOAC) according to RDC n° 14 to capture light dirt and in the microbiological analyzes, were used the methods of the International Organization for Standardization (ISO) according to RDC nº 12 to evaluate total and thermotolerant coliforms, fungi and Salmonella spp. In the research of extraneous materials, only three brands of chamomile were approved, the rest of the teas being in disagreement with the current legislation because they are above the acceptable tolerance limit. In the evaluation of coliforms and Salmonella sp. all samples were approved, however, there was a considerable growth of filamentous fungi in these samples

Crescimento de fungos potencialmente produtores de micotoxinas em ervas utilizadas para chá coletadas em feiras livres do Distrito Federal / Growth of fungi potentially mycotoxin-producing used in herbal tea collected from fairs of the Distrito Federal

O objetivo deste trabalho foi avaliar a presença, isolar e identificar fungos filamentosos, produtores de micotoxinas Aspergillus sp., Penicillium sp. e Fusarium sp em amostras de ervas utilizadas em chá comercializadas em feiras livres do Distrito Federal...

Determinação da qualidade microbiológica e físico-química de chás de Cymbopogon citratus (D. C) Stapf (capim-limão) / Evaluation of the microbiological and physical-chemical qualities of lemongrass tea

Em função do grande volume de produção e comercialização do capim-limão, estima-se que uma contaminação microbiológica deste produto possa representar importante risco para a saúde pública. Esta pesquisa visou avaliar marcas de chá de capim-limão, em relação às qualidades microbiológica e físico-química, tendo como base a legislação brasileira do Ministério da Saúde. Nenhuma das amostras apresentou Salmonella sp, porém em 50% delas, houve presença de coliformes a 35ºC. Em três amostras, evidenciaram-se coliformes a 45ºC, com presença de Escherichia coli em uma destas. 81,25% das amostras apresentaram bolores e leveduras, porém sem relação direta com os teores de umidade observados. Dentre os fungos presentes, identificou-se Aspergillus niger, no entanto sem produção de aflatoxinas. Todos infusos analisados negativaram a contaminação evidenciada nos testes com o produto seco. Os resultados indicaram possíveis falhas nos procedimentos pós-colheita e de comercialização. A implementação do Sistema APPCC (HACCP) poderia substancialmente minimizar esta contaminação.

Considering the great volume of lemongrass production and commercialization, it is estimated that a potential microbiological contamination of this product could represent an important hazard to public health. This study was performed to evaluate different brands of lemongrass tea, regarding their microbiological and physical-chemical quality, based on the legislation of the Brazilian Health Ministry. No traces of Salmonella sp were found, but in 50% of samples, the presence of coliforms was detected at 35ºC. Three samples presented coliforms at 45ºC, with Escherichia coli found in one of them. 81.25% of samples presented molds and yeasts. Among the fungi present, Aspergillus niger was identified, but aflatoxins were absent. None of the infusions analyzed presented the contamination evidenced in the dry product. The results obtained may be indicative of failure in procedures of postharvest and commercialization. The implementation of a hazard analysis and critical control point system (HACCP) could reduce this contamination substantially.

Do leaf surface characteristics affect Agrobacterium infection in tea [Camellia sinensis (L.) O Kuntze]?

The host range specificity of Agrobacterium with five tea cultivars and an unrelated species (Artemisia parviflora) having extreme surface characteristics was evaluated in the present study. The degree of Agrobacterium infection in the five cultivars of tea was affected by leaf wetness, micro-morphology and surface chemistry. Wettable leaf surfaces of TV1, Upasi-9 and Kangra jat showed higher rate (75%) of Agrobacterium infection compared to Upasi-10 and ST-449, whereas non-wettable leaves of A. parviflora showed minimum (25%) infection. This indicated that the leaves with glabrous surface having lower q (larger surface area covered by water droplet), higher phenol and wax content were more suitable for Agrobacterium infection. Caffeine fraction of tea promoted Agrobacterium infection even in leaves poor in wax (Upasi-10), whereas caffeine-free wax inhibited both Agrobacterium growth and infection. Thus, study suggests the importance of leaf surface features in influencing the Agrobacterium infection in tea leaf explants. Our study also provides a basis for the screening of a clone/cultivar of a particular species most suitable for Agrobacterium infection the first step in Agrobacterium-mediated genetic transformation.

Caffeine in tea plants [Camellia sinensis (L) O. Kuntze]: in situ lowering by Bacillus licheniformis (Weigmann) Chester.

Tea plants (Camellia sinensis) contain 5-6% caffeine that is responsible for the stimulating effect of the beverage. As the tolerance to caffeine varies among individuals, low caffeine tea would be an ideal alternative. While assessing the potential of a few selected bacteria-Bacillus licheniformis, B. subtilis and B. firmus, to multiply on nutrient medium supplemented with glucose (5%) and tea leaf extract (2%), it was observed that only B. licheniformis could proliferate on this medium. Hence, B. licheniformis was used for further studies. Tea plants were sprayed with a suspension of B. licheniformis at a dilution of 5 x 10(8) CFU/ml containing 0.1% Tween 80 as surfactant. In situ lowering of caffeine from tea leaves was evident without affecting the quality of the other tea components. Further, there was no change in the morphological and physiological characteristics as well. It is suggested that spraying of B. licheniformis may be useful in yielding decaffeinated tea with good flavour and aroma.

Protease from Sporosarcina sp. RRLJ 1.

Protease was isolated from Sporosarcina RRLJ1 which was collected from acid tea (Camellia sinensis) plantations. It showed potential for production of the enzyme for commercial purposes. The study revealed that optimum pH for growth of the organism was 6.5-7 and supplement of casein (1%) in the medium was required for production of protease. Enzyme production and enzyme activity was maximum in 72 hr old broth culture. Maximum activity of the enzyme was found at pH 6.5.

Fungicidal and insect controlling properties of Proteus strain RRLJ 16, isolated from tea, Camellia sinensis (L) O Kuntze, plantations.

A strain of Proteus RRLJ 16, isolated from acid (pH 4.5-5.5) iron rich tea (Camellia sinensis) plantation soil, produced siderophores with single absorption peak at 370 nm when cultured in iron free medium. Extracted crude fraction of siderophores and live cultures showed in vitro antibiosis against five species of pathogenic fungi. When the strain was cultured in a normal bacteriological medium without iron stress, it produced an insect repellent compound. The culture filtrate sprayed (dilution of 1:100 in water) on tea plants infected with pink mites or green flies, the insect populations disappeared from the plants. Termite galleries sprayed similarly showed no termite activity after 24 hr of spraying. No reinfestation by insects was observed on treated plants for more than one year.