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Efeito de um branqueamento combinado com ultrassons nas características físico-químicas de uma espécie halófita (Salicornia ramosíssima)
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Abstract(s)
Com a necessidade de apresentar produtos saudáveis, de rápida e fácil utilização para o consumidor, têm vindo a ser desenvolvidos novos métodos de processamento de alimentos na indústria alimentar, que visam a obtenção de produtos seguros e de qualidade, aumentando o seu tempo de conservação.
Neste trabalho estudou-se o efeito de um branqueamento combinado com ultrassons na qualidade da Salicornia ramosissima, planta halófita, que se apresenta como uma excelente alternativa ao sal correntemente utilizado na alimentação.
O processamento combinado imersão em água com ultrassons foi efetuado a cinco temperaturas diferentes entre 75-98 °C, e tempos, 0,17-7,5 min, com uma potência de 125 W e frequência de 20 kHz.
Após o processamento determinou-se a atividade da enzima peroxidase, para verificar a eficácia deste tratamento emergente na sua inativação, e vários parâmetros de qualidade, como a textura, cor, teor em compostos fenólicos totais e atividade antioxidante, de modo a obter um alimento processado com alterações mínimas nas suas características.
A aplicação do branqueamento combinado com ultrassons reduziu a atividade da enzima peroxidase acima de 90 % quando aplicadas temperaturas e tempos de 85 °C, 5 min, 90 °C, 2,5 e 5 min e 98 °C, 0,5 e 1 min.
Relativamente aos parâmetros de qualidade analisados, a uma temperatura de processamento de 98 °C durante 0,5 min foi possível reduzir cerca de 90 % da atividade enzimática, obtendo uma amostra ligeiramente mais firme (4 %), mais escura, devido à diminuição de cerca de 10 % de luminosidade e mais verde, visto que, o parâmetro de cor a, aumentou, aproximadamente 60 %. Além disso, esta aplicação promoveu um aumento da atividade antioxidante (16 %) que, de certo modo, vem contrabalançar a diminuição do teor em compostos fenólicos totais (57 %).
Em suma, este tratamento permitiu reduzir a atividade enzimática em 90 %, possibilitando a diminuição do tempo de processamento e, em alguns casos, melhorar certos parâmetros de qualidade analisados, nomeadamente a textura, cor e atividade antioxidante.
In the food industry new methods of food processing have been developed, in one hand to obtain safe and quality products and increasing their shelf life, and on the other hand to present healthy food products that are easy to use. In this work the effect of a combined blanching treatment with ultrasound was studied on the quality of Salicornia ramosissima, a halophyte plant, which is an excellent alternative to the salt currently used in food. A combined water immersion processing with ultrasound was carried out at five different temperatures and times between 75-98 °C and 0.17-7.5 min, with a power of 125 W and a frequency of 20 kHz. After the processing, the peroxidase enzyme activity was determined to verify the effectiveness of this emergent treatment in its inactivation, and several quality parameters, such as texture, color, total phenolic compounds content and antioxidant activity were evaluated, in order to obtain a processed food with minimal changes in its characteristics. The application of the combined blanching with ultrasound reduced peroxidase enzyme activity above 90% when applied at temperatures and times of 85 ° C, 5 min, 90 ° C, 2.5 and 5 min and 98 ° C, 0.5 and 1 min. Regarding the analyzed quality parameters, at a processing temperature of 98 °C for 0.5 min it was possible to reduce the enzymatic activity to about 90%, obtaining a slightly firmer sample (4%), darker due to the decrease of about 10 % in lightness, and greener, since the color parameter a increased by approximately 60 %. In addition, this application promoted an increase in antioxidant activity (16 %), which, in a way, counterbalances the decrease in total phenolic compounds content (57 %). This treatment allowed reducing 90% of the enzymatic activity, at shorter processing times and, in some cases, to improve some of the quality parameters analyzed, namely texture, color and antioxidant activity.
In the food industry new methods of food processing have been developed, in one hand to obtain safe and quality products and increasing their shelf life, and on the other hand to present healthy food products that are easy to use. In this work the effect of a combined blanching treatment with ultrasound was studied on the quality of Salicornia ramosissima, a halophyte plant, which is an excellent alternative to the salt currently used in food. A combined water immersion processing with ultrasound was carried out at five different temperatures and times between 75-98 °C and 0.17-7.5 min, with a power of 125 W and a frequency of 20 kHz. After the processing, the peroxidase enzyme activity was determined to verify the effectiveness of this emergent treatment in its inactivation, and several quality parameters, such as texture, color, total phenolic compounds content and antioxidant activity were evaluated, in order to obtain a processed food with minimal changes in its characteristics. The application of the combined blanching with ultrasound reduced peroxidase enzyme activity above 90% when applied at temperatures and times of 85 ° C, 5 min, 90 ° C, 2.5 and 5 min and 98 ° C, 0.5 and 1 min. Regarding the analyzed quality parameters, at a processing temperature of 98 °C for 0.5 min it was possible to reduce the enzymatic activity to about 90%, obtaining a slightly firmer sample (4%), darker due to the decrease of about 10 % in lightness, and greener, since the color parameter a increased by approximately 60 %. In addition, this application promoted an increase in antioxidant activity (16 %), which, in a way, counterbalances the decrease in total phenolic compounds content (57 %). This treatment allowed reducing 90% of the enzymatic activity, at shorter processing times and, in some cases, to improve some of the quality parameters analyzed, namely texture, color and antioxidant activity.
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Keywords
Salicornia ramosissima Halófita Tratamentos emergentes Qualidade