Aplicação de ultrassom de potência para a produção de malte de trigo
Carregando...
Data
2019-02-22
Autores
Guimarães, Bianca
Título da Revista
ISSN da Revista
Título de Volume
Editor
Universidade Estadual Paulista (Unesp)
Resumo
O grão de trigo é considerado uma das principais fontes de energia (importância nutricional), principal insumo de vários alimentos (pães, bolos, farinhas, entre outros) e, vem sendo cada vez mais utilizado na indústria cervejeira. O malte de trigo está ganhando maior destaque no setor cervejeiro por caracterizar cervejas com gostos, aromas e cores diferentes das cervejas feitas com os outros tipos de maltes. A maltagem é a embebição dos grãos com água seguida de uma germinação e secagem controlada. O ultrassom é uma nova tecnologia que vem sendo utilizada no processo de alimentos e sua utilização pode apresentar melhorias no controle de parâmetros de produtos alimentícios ou processos, influenciando na cinética dos mesmos. Nesse contexto, foram analisadas as propriedades físicas do grão de trigo de acordo com a variação do teor de umidade (14,4 até 90,9 % b.s.) e a potência ultrassônica real transmitida pelo método calorimétrico. Além disso, foi investigada a influência da aplicação do ultrassom de potência (0, 500, 1000, 1500 W) e da temperatura (15, 20, 25 °C) no processo de hidratação do grão de trigo, assim como os efeitos dessa aplicação na germinação. Os modelos matemáticos (Peleg e exponencial) foram utilizados para descrever a cinética de maceração. Foi verificado que a maioria das propriedades físicas variou significativamente (p<0,05) com o aumento da umidade e correlacionaram por meio de um ajuste polinomial de segunda ordem com exceção da área superficial. Os valores iniciais e finais de cada propriedade física foram de 6,460,04 até 6,550,05 mm para o comprimento; de 3,290,04 até 3,500,02 mm para a largura; de 2,620,02 até 2,730,06 mm para a espessura; de 4,130,02 até 4,270,03 mm para o diâmetro médio aritmético; de 3,920,01 até 3,970,04 mm para o diâmetro médio geométrico; de 3,550,03 até 4,480,04 mm para o diâmetro equivalente a uma esfera; de 58,180,16 até 60,630,11 % para a esfericidade; de 38,610,05 até 59,571,73 g para a massa de 1000 grãos; de 45,910,34 até 48,55 0,91 mm² para a área superficial; de 815,137,80 até 678,135,93 Kg/m³ para a densidade bulk; de 1600,1133,13 até 1267,700,50 Kg/m³ para a densidade real e de 49,041,46 até 46,510,45 % para a porosidade. A potência real é sempre menor que a potência nominal do equipamento e o aumento da potência nominal resultou em menores rendimentos de conversão, mas em maiores valores absolutos. Assim, para a potência nominal de 500, 1000 e 1500 W, tem-se uma potência real transmitida de 60,454,11; 76,553,15 e 101,234,24 W, respectivamente. A taxa de hidratação aumentou com o aumento da potência do ultrassom e da temperatura e, o modelo exponencial foi o que melhor representou a cinética de hidratação com R² acima de 0,992 e NRMSE abaixo de 2,221. Já o poder germinativo e o tempo médio de germinação não sofreram influência da variação da temperatura e da potência. Assim, esse aumento da taxa de absorção de água e, consequentemente, a diminuição do tempo de maceração faz do ultrassom de potência uma possível tecnologia para melhorar o processo de produção de malte de trigo.
Wheat is considered one of the main sources of energy (nutritional importance), the main input of various foods (breads, cakes, flour, among others). It has, currently, been more used in the brewing industry. Wheat malt is becoming more prominence in the brewing sector because it characterizes beers with different tastes, aromas and colors differently from beers made with other types of malts. Malting is the imbibition of the grains with water followed by a controlled germination and drying. Ultrasound is a new technology that has been used in food process and its use may present improvements in the control of food product parameters or process, influencing their kinetics. In this context, the physical properties of the wheat grain were determined as a function of moisture content (14,4 to 90,9 % b.s.) and the real power transmitted was estimated by the calorimetric method. In addition, the influence of the application of power ultrasound (0, 500, 1000, 1500 W) and temperature (15, 20 e 25 °C) during steeping of wheat grain was investigated, as well as some effects of this application in the germination step of malt. Mathematical models (Peleg and exponential) were used to describe the steeping process. It was verified that most of physical properties varied significantly (p<0,05) with increasing moisture content and they were correlated by a second order polynomial fit with the exception of surface area. The initial and final values of each physical properties were from 6,460,04 to 6,550,05 mm for the length; from 3,290,04 to 3,500,02 mm for the width; from 2,620,02 to 2,730,06 mm for the thickness; from 4,130,02 to 4,270,03 mm for the arithmetic mean diameter; from 3,920,01 to 3,970,04 mm for the geometric mean diameter; from 3,550,03 to 4,480,04 mm for the equivalente diameter of a sphere; from 58,18 0,16 to 60,630,11 % for the sphericity; from 38,610,05 to 59,571,73 g for the mass of 1000 grains; from 45,910,34 to 48,550,91 mm² for the surface area; from 815,137,80 to 678,135,93 Kg/m³ for the bulk density; from 1600,1133,13 to 1267,700,50 Kg/m³ for the real density and from 49,041,46 to 46,510,45 % for the porosity. The equipment real power is always lower than the nominal power of the equipment and the increase of the nominal power resulted in lower conversion yields, but higher absolute values. Thus, for the nominal power of 500, 1000 and 1500 W, there is a real power transmitted from 60,454,11; 76,553,15 and 101,234,24 W, respectively. The water uptake increased with increasing power ultrasound and temperature and the exponential model was the one that best represented the kinetics of hydration hidratação with R² above 0,992 and NRMSE bellow 2,221. The germination power and the mean germination time weren’t influenced by the temperature and power variation. Thus, this water uptake increases and, consequently, maceration time decrease makes the power ultrasound a possible technology to improve the process of wheat malt production.
Wheat is considered one of the main sources of energy (nutritional importance), the main input of various foods (breads, cakes, flour, among others). It has, currently, been more used in the brewing industry. Wheat malt is becoming more prominence in the brewing sector because it characterizes beers with different tastes, aromas and colors differently from beers made with other types of malts. Malting is the imbibition of the grains with water followed by a controlled germination and drying. Ultrasound is a new technology that has been used in food process and its use may present improvements in the control of food product parameters or process, influencing their kinetics. In this context, the physical properties of the wheat grain were determined as a function of moisture content (14,4 to 90,9 % b.s.) and the real power transmitted was estimated by the calorimetric method. In addition, the influence of the application of power ultrasound (0, 500, 1000, 1500 W) and temperature (15, 20 e 25 °C) during steeping of wheat grain was investigated, as well as some effects of this application in the germination step of malt. Mathematical models (Peleg and exponential) were used to describe the steeping process. It was verified that most of physical properties varied significantly (p<0,05) with increasing moisture content and they were correlated by a second order polynomial fit with the exception of surface area. The initial and final values of each physical properties were from 6,460,04 to 6,550,05 mm for the length; from 3,290,04 to 3,500,02 mm for the width; from 2,620,02 to 2,730,06 mm for the thickness; from 4,130,02 to 4,270,03 mm for the arithmetic mean diameter; from 3,920,01 to 3,970,04 mm for the geometric mean diameter; from 3,550,03 to 4,480,04 mm for the equivalente diameter of a sphere; from 58,18 0,16 to 60,630,11 % for the sphericity; from 38,610,05 to 59,571,73 g for the mass of 1000 grains; from 45,910,34 to 48,550,91 mm² for the surface area; from 815,137,80 to 678,135,93 Kg/m³ for the bulk density; from 1600,1133,13 to 1267,700,50 Kg/m³ for the real density and from 49,041,46 to 46,510,45 % for the porosity. The equipment real power is always lower than the nominal power of the equipment and the increase of the nominal power resulted in lower conversion yields, but higher absolute values. Thus, for the nominal power of 500, 1000 and 1500 W, there is a real power transmitted from 60,454,11; 76,553,15 and 101,234,24 W, respectively. The water uptake increased with increasing power ultrasound and temperature and the exponential model was the one that best represented the kinetics of hydration hidratação with R² above 0,992 and NRMSE bellow 2,221. The germination power and the mean germination time weren’t influenced by the temperature and power variation. Thus, this water uptake increases and, consequently, maceration time decrease makes the power ultrasound a possible technology to improve the process of wheat malt production.
Descrição
Palavras-chave
Trigo, Ultrassom, Propriedades físicas, Hidratação, Germinação, Wheat, Ultrasound, Physical properties, Hydration, Germination