ABSTRACT
O tempo de conservação do camarão é muito curto, e sua estocagem é difícil. O tratamento do metabissulfito de sódio e a irradiação foi realizado com o objetivo de prolongar a vida útil do produto. O metabissulfito de sódio é um antioxidante usado para evitar o aparecimento de melanose no camarão, logo após a pesca. O principal objetivo do trabalho foi avaliar o efeito da radiação gama em camarões (Pleoticus muelleri) refrigerados com e sem adição de metabissulfito, por meio de características sensoriais (cor, odor e aspecto geral) e o aparecimento de ?black spot?. Foram investigados 4 grupos de amostras: amostra controle (0 kGy), amostra adicionada de 2% de metabissulfito de sódio, amostra irradiada a 1,5 kGy, amostra irradiada com 1,5 kGy e adicionada 1,25% de metabissulfito de sódio. Concluiu-se que a irradiação na dose estudada não altera o produto quanto a sua qualidade sensorial comparado a amostra controle. O tratamento em solução de metabissulfito de sódio a 2% apresenta melhor resultado do que as demais amostras tanto na formação de ?black spot? quanto sensorialmente.
Shrimp conservation time is very short, making its storage difficult. Aiming to extend its useful life, a treatment with sodium metabisulphite and irradiation was used. Sodium metabisulphite is an antioxidant used to prevent the occurrence of melanosis in refrigerated shrimp right after fishing. The main goal of this study is to evaluate the effect of gamma radiation on shrimp (Pleoticus muelleri), with and without the addition of sodium metabisulphite, regarding its sensorial characteristics (color, odor and general appearance) and the appearing of ?black spots?. Four samples were investigated, divided in 4 groups: control samples (0 kGy), samples with sodium metabisulphite 2%, samples irradiated at 1.5 kGy without sodium metabisulphite, and samples irradiated at 1,5 kGy with sodium metabisulphite 1.25%. It was concluded that irradiation at the studied dose does not alter the product, regarding its sensorial quality, when compared to the control sample. The treatment with sodium metabisulphite solution at 2% shows a better result than the other samples for the formation of ?black spot? as well as for the sensorial aspects.
El tiempo de conservación del camarón es muy corto, y su almacenamiento es difícil. El tratamiento con meta bisulfito de sodio y la irradiación se realizó con el objetivo de prolongar la vida útil del producto. El meta bisulfito de sodio es un antioxidante usado para evitar la aparición de melanosis en el camarón, luego después de la pesca. El principal objetivo del estudio fue evaluar el efecto de la radiación gamma en camarones (Pleoticus muelleri) refrigerados con y sin adicción de meta bisulfito, por medio de características sensoriales (color, olor y aspecto general) y la aparición de ?Black spot?. Se investigó 4 grupos de muestras: muestra control (0 kGy), muestra adicionada de 2% de meta bisulfito de sodio, muestra irradiada a 1,5 kGy y adicionada 1,25% de meta bisulfito de sodio. Se concluyó que la irradiación en la dosis estudiada no altera el producto cuanto a su calidad sensorial, comparado a la muestra control. El tratamiento en solución de meta bisulfito de sodio a 2% presenta mejor resultado que las demás muestras, tanto en la formación de ?Black spot? como sensorialmente.
ABSTRACT
This study was aimed to investigate the effects of chemical treatment as well as pasteurization on the shelf life of “kunun zaki” (a non-alcoholic beverage commonly consumed by the people of northern Nigeria), to increase the shelf life and preserve the quality of the beverage. Kunun zaki was produced by dry -cleaning, washing, steeping (sorghum for 24 hours and maize for 48 hours), malting for 72 hours at room temperature, wet milling, mixing, cooking and filtering to obtain the liquor. The product was treated with 0.1% sodiumbenzoate or sodium metabisulphite or their combinations. These were packed and pasteurized in bottles at 60oC for one hour. Another batch of samples were chemically treated but not pasteurized. Pasteurized samples which were not chemically treated served as control. Samples were stored at ambient temperature and monitored for changes in pH, titratable acidity, total solid, total sugars, acceptability and colour for four weeks. The pH and sugar decreased and the decrease was more pronounced in non pasteurized samples irrespective of chemical treatment. Titratable acidity increased in all samples with storage time. Pasteurized kunun zaki which received no chemical treatment deteriorated after one week of storage. Samples treated with 0.1% sodium benzoate or sodium metabisulphite or their combination without pasteurization deteriorated after two weeks of storage. Samples which were similarly treated and pasteurized were stable for more than three weeks. Pasteurization enhanced effectiveness of chemical preservation and acceptability of kunun zaki.
ABSTRACT
This study was aimed to investigate the effects of chemical treatment as well as pasteurization on the shelf life of “kunun zaki” (a non-alcoholic beverage commonly consumed by the people of northern Nigeria), to increase the shelf life and preserve the quality of the beverage. Kunun zaki was produced by dry -cleaning, washing, steeping (sorghum for 24 hours and maize for 48 hours), malting for 72 hours at room temperature, wet milling, mixing, cooking and filtering to obtain the liquor. The product was treated with 0.1% sodiumbenzoate or sodium metabisulphite or their combinations. These were packed and pasteurized in bottles at 60oC for one hour. Another batch of samples were chemically treated but not pasteurized. Pasteurized samples which were not chemically treated served as control. Samples were stored at ambient temperature and monitored for changes in pH, titratable acidity, total solid, total sugars, acceptability and colour for four weeks. The pH and sugar decreased and the decrease was more pronounced in non pasteurized samples irrespective of chemical treatment. Titratable acidity increased in all samples with storage time. Pasteurized kunun zaki which received no chemical treatment deteriorated after one week of storage. Samples treated with 0.1% sodium benzoate or sodium metabisulphite or their combination without pasteurization deteriorated after two weeks of storage. Samples which were similarly treated and pasteurized were stable for more than three weeks. Pasteurization enhanced effectiveness of chemical preservation and acceptability of kunun zaki.
ABSTRACT
Os fungos termorresistentes dos gêneros Byssochlamys, Neosartorya e Talaromyces representam grave problema para a indústria processadora de alimentos, especialmente de frutas e hortaliças, em virtude da ocorrência de ascosporos extremamente resistentes e/ou de micotoxinas termo estáveis. Com o propósito de fornecer subsídios quanto ao uso de quantidades mais racionais de conservantes pela indústria de alimentos e, portanto, tornar seu consumo menos danoso à população, o presente estudo determinou in vitro a concentração mínima de metabissulfito de sódio, benzoato de sódio e sorbato de potássio necessária e suficiente para inibir o crescimento micelial e a germinação de ascósporos de B. fulva, N. fischeri e T.flavus em meio de cultivo acidificado (pH 3,5). Foi demonstrado que metabissulfito de sódio em baixas concentrações é tão eficiente na inibição dos fungos mencionados quanto aos demais conservantes em altas concentrações. Por comparação com os procedimentos utilizados pelas indústrias de alimentos, é possível inferir que estas podem reformular o uso de conservantes, considerando-se o tipo de matéria-prima, a temperatura de processamento, a combinação e concentração efetivamente necessária de aditivos, bem como os efeitos tóxicos desses compostos para a saúde humana.