Planetary ball-mill as a versatile tool to controlled potato starch modification to broaden its industrial applications.

Pure potato starch has been modified by high-energy-ball-milling as a function of energy supplied, aiming to obtain products for different possibilities of industrial application. Burgios's equation has been used to calculate the energy supplied. The effect of the milling has been followed by a characterization of the starch morphology, crystallinity, solubility, swelling, retrogradation, viscosity, apparent viscosity, functional groups, and reducing sugar concentration. The high-energy-ball-milling not only changes the physical properties but also induces the mechanolysis of potato starch, breaking the glycosidic linkages of the starch molecules. A representation of the possible mechanism of starch mechanolysis is proposed. Three stages of the transformation of potato starch through high-energy ball-milling can be identified. Each of these stages generates starch with properties that can be used in different industrial applications.

Enzymatic hydrolysis of carbohydrates in by-products of processed rice / Hidrólise enzimática de carboidratos em coprodutos do arroz beneficiado

ABSTRACT: Over post-harvest steps of rice, from pre-cleaning to processing, a large amount of by-product is generated. Some of these by-products, due to their high starch and fiber content can be used in ethanol production. The objective was to evaluate the effect of enzymatic hydrolysis conditions on the production of reducing sugars, from pre-cleaning residue and type III paddy rice, as well as the effect of the pre-treatment of its fibers, targeting the use of these residues in ethanol fuel production. The proximate analysis was performed, followed by the pre-treatment of samples. Enzymatic hydrolysis was conducted in two ways: using one enzyme at a time or applying them simultaneously. The starch content was 41.18 and 53.41%; the fibers were 30.44 and 23.39%, of which 6.53 and 4.41% were lignin, for the pre-cleaning residue and paddy rice, respectively. Alkaline pre-treatment reduce lignin content by 47.94 and 18.23% for the pre-cleaning residue and type III paddy rice, respectively. Hydrolysis efficiency was 22.61 and 15.32% for the cellulase enzyme, and 82.18 and 87.07% for the amylolytic enzymes in the pre-cleaning residue and type III paddy rice, respectively. The hydrolysis with the separated enzymes presented higher reducing sugar yields. Therefore, the pre-cleaning residue and type III paddy rice can be used for ethanol production by its enzymatic hydrolysis, aiming to add value and to increase the sustainability of the rice production chain.

RESUMO: Durante o processamento do arroz são gerados grandes volumes de resíduos, desde a pré-limpeza até o beneficiamento. Alguns destes resíduos, por apresentarem elevado teor de amido e fibras, podem ser utilizados na produção de etanol. O objetivo foi avaliar a viabilidade técnica do resíduo da pré-limpeza e do arroz em casca tipo III como matéria-prima para a produção de etanol, a partir da hidrólise enzimática. Foi analisada a composição centesimal dos resíduos e, em seguida, o pré-tratamento. A hidrólise enzimática foi realizada por dois procedimentos, o primeiro com as enzimas separadas e o segundo com as enzimas atuando simultaneamente. O teor de amido foi de 41,18 e 53,41%; de fibras 30,44% e 23,39%, dentre as quais 6,53 e 4,41% foi de lignina, para o resíduo da pré-limpeza e o arroz em casca, respectivamente. Com o pré-tratamento alcalino, a lignina reduziu em 47,94 e 18,23% para o resíduo da pré-limpeza e para o arroz em casca tipo III, respectivamente. A eficiência da hidrólise foi de 22,61 e 15,32% para a enzima celulase, e 82,18 e 87,07% para as enzimas amilolíticas no resíduo da pré-limpeza e no arroz em casca tipo III, respectivamente. A hidrólise com as enzimas separadas apresentou maior rendimento em açúcar redutor. Sendo assim, o resíduo da pré-limpeza e o arroz em casca do tipo III podem ser considerados matérias-primas viáveis para produção de etanol, visando agregação de valor e o aumento da sustentabilidade na cadeia produtiva do arroz.

Enzymatic hydrolysis of carbohydrates in by-products of processed rice / Hidrólise enzimática de carboidratos em coprodutos do arroz beneficiado

Over post-harvest steps of rice, from pre-cleaning to processing, a large amount of by-product is generated. Some of these by-products, due to their high starch and fiber content can be used in ethanol production. The objective was to evaluate the effect of enzymatic hydrolysis conditions on the production of reducing sugars, from pre-cleaning residue and type III paddy rice, as well as the effect of the pre-treatment of its fibers, targeting the use of these residues in ethanol fuel production. The proximate analysis was performed, followed by the pre-treatment of samples. Enzymatic hydrolysis was conducted in two ways: using one enzyme at a time or applying them simultaneously. The starch content was 41.18 and 53.41%; the fibers were 30.44 and 23.39%, of which 6.53 and 4.41% were lignin, for the pre-cleaning residue and paddy rice, respectively. Alkaline pre-treatment reduce lignin content by 47.94 and 18.23% for the pre-cleaning residue and type III paddy rice, respectively. Hydrolysis efficiency was 22.61 and 15.32% for the cellulase enzyme, and 82.18 and 87.07% for the amylolytic enzymes in the pre-cleaning residue and type III paddy rice, respectively. The hydrolysis with the separated enzymes presented higher reducing sugar yields. Therefore, the pre-cleaning residue and type III paddy rice can be used for ethanol production by its enzymatic hydrolysis, aiming to add value and to increase the sustainability of the rice production chain.(AU)

Durante o processamento do arroz são gerados grandes volumes de resíduos, desde a pré-limpeza até o beneficiamento. Alguns destes resíduos, por apresentarem elevado teor de amido e fibras, podem ser utilizados na produção de etanol. O objetivo foi avaliar a viabilidade técnica do resíduo da pré-limpeza e do arroz em casca tipo III como matéria-prima para a produção de etanol, a partir da hidrólise enzimática. Foi analisada a composição centesimal dos resíduos e, em seguida, o pré-tratamento. A hidrólise enzimática foi realizada por dois procedimentos, o primeiro com as enzimas separadas e o segundo com as enzimas atuando simultaneamente. O teor de amido foi de 41,18 e 53,41%; de fibras 30,44% e 23,39%, dentre as quais 6,53 e 4,41% foi de lignina, para o resíduo da pré-limpeza e o arroz em casca, respectivamente. Com o pré-tratamento alcalino, a lignina reduziu em 47,94 e 18,23% para o resíduo da pré-limpeza e para o arroz em casca tipo III, respectivamente. A eficiência da hidrólise foi de 22,61 e 15,32% para a enzima celulase, e 82,18 e 87,07% para as enzimas amilolíticas no resíduo da pré-limpeza e no arroz em casca tipo III, respectivamente. A hidrólise com as enzimas separadas apresentou maior rendimento em açúcar redutor. Sendo assim, o resíduo da pré-limpeza e o arroz em casca do tipo III podem ser considerados matérias-primas viáveis para produção de etanol, visando agregação de valor e o aumento da sustentabilidade na cadeia produtiva do arroz.(AU)

Enzymatic hydrolysis of carbohydrates in by-products of processed rice / Hidrólise enzimática de carboidratos em coprodutos do arroz beneficiado

Over post-harvest steps of rice, from pre-cleaning to processing, a large amount of by-product is generated. Some of these by-products, due to their high starch and fiber content can be used in ethanol production. The objective was to evaluate the effect of enzymatic hydrolysis conditions on the production of reducing sugars, from pre-cleaning residue and type III paddy rice, as well as the effect of the pre-treatment of its fibers, targeting the use of these residues in ethanol fuel production. The proximate analysis was performed, followed by the pre-treatment of samples. Enzymatic hydrolysis was conducted in two ways: using one enzyme at a time or applying them simultaneously. The starch content was 41.18 and 53.41%; the fibers were 30.44 and 23.39%, of which 6.53 and 4.41% were lignin, for the pre-cleaning residue and paddy rice, respectively. Alkaline pre-treatment reduce lignin content by 47.94 and 18.23% for the pre-cleaning residue and type III paddy rice, respectively. Hydrolysis efficiency was 22.61 and 15.32% for the cellulase enzyme, and 82.18 and 87.07% for the amylolytic enzymes in the pre-cleaning residue and type III paddy rice, respectively. The hydrolysis with the separated enzymes presented higher reducing sugar yields. Therefore, the pre-cleaning residue and type III paddy rice can be used for ethanol production by its enzymatic hydrolysis, aiming to add value and to increase the sustainability of the rice production chain.

Durante o processamento do arroz são gerados grandes volumes de resíduos, desde a pré-limpeza até o beneficiamento. Alguns destes resíduos, por apresentarem elevado teor de amido e fibras, podem ser utilizados na produção de etanol. O objetivo foi avaliar a viabilidade técnica do resíduo da pré-limpeza e do arroz em casca tipo III como matéria-prima para a produção de etanol, a partir da hidrólise enzimática. Foi analisada a composição centesimal dos resíduos e, em seguida, o pré-tratamento. A hidrólise enzimática foi realizada por dois procedimentos, o primeiro com as enzimas separadas e o segundo com as enzimas atuando simultaneamente. O teor de amido foi de 41,18 e 53,41%; de fibras 30,44% e 23,39%, dentre as quais 6,53 e 4,41% foi de lignina, para o resíduo da pré-limpeza e o arroz em casca, respectivamente. Com o pré-tratamento alcalino, a lignina reduziu em 47,94 e 18,23% para o resíduo da pré-limpeza e para o arroz em casca tipo III, respectivamente. A eficiência da hidrólise foi de 22,61 e 15,32% para a enzima celulase, e 82,18 e 87,07% para as enzimas amilolíticas no resíduo da pré-limpeza e no arroz em casca tipo III, respectivamente. A hidrólise com as enzimas separadas apresentou maior rendimento em açúcar redutor. Sendo assim, o resíduo da pré-limpeza e o arroz em casca do tipo III podem ser considerados matérias-primas viáveis para produção de etanol, visando agregação de valor e o aumento da sustentabilidade na cadeia produtiva do arroz.

High-energy ball milling treatment of soybean for Bacillus thuringiensis culture media.

Soybean meal has been intensively used as a substrate in culture media for several microorganisms. However, the fermentable sugar containing the soybean needs to be released from the solid matrix through different processes. Against this backdrop, the present study explores the use of high-energy ball milling as a one-step treatment method for expedited production of fermentable sugars of textured soybean. The best result is observed after only 5 min of milling, obtaining 34.1 times more fermentable sugars than untreated textured soybean, and 2.5 times more than commercially used soybean meal. Notably, the textured soybean ball-milled has been used as a substrate for Bacillus thuringiensis var. kurstaki HD-73 fermentation. The cell and spore production is also compared with a standard Rowe media. The maximum cell concentration obtained in the entire fermentation process using ball-milled textured soybean media is found to be higher than the concentration obtained using the standard Rowe media. In addition, it is observed that there is a direct correlation between maximum cell production and reducing sugar concentration generated by the high-energy ball milling treatment. No fermentation inhibitors or by-products are generated during the physical treatment.

Studies on Akamu, a traditional fermented maize food / Estudios en Akamu, una comida tradicional de maiz fermentado

Microbiological and some physicochemical properties of akamu, a fermented maize food were studied. Microbial population, pH, titratable acidity, protein, sugar and starch were measured during the fermentation. The initial microflora consisted ofa heterogenous mixture of microorganisms namely Lactobacillus delbrueckii, Lactobacillus plantarum, Lactobacillus fermentum, Lactobacillus amylovorus, Pseudomonas aeruginosa, Pseudomonas alkaligenes, Bacillus cereus, Bacillus licheniformis, Bacillus subtilis, Candida utilis, Candida tropicalis, Saccharomyces cerevisiae, Aspergillus oryzae, Aspergillus niger, Penicillium citrinum, Rhizopus micros-porus and Rhizopus oligosporus. Within 24 h, lactobacilli and aerobic mesophilic bacteria accounted for a major portion of the total microflora. The lactobacilli numbers increased from 1.6 x107 cfu/g after24 h to 7.1 x108 cfu/g after 72 h. Total aerobic mesophilic bacteria increased from 2.5 x109 cfu/g after 24 h to 4.2 x108 cfu/g after 72 h. Enterobacteriaceae count decreased from 6.3 x 103 cfu/g after 24 h to 2.5x102 cfu/g after 72 h, although this level remained significantly high for a finished food product. Yeasts increased steadily and reached 6.8 x105 cfu/g after 72 h. Mould counts decreased from 6.3 x103 cfu/g after 24 h to 1.3 x102 cfu/g after 72 h. Moulds were largely responsible for amylolytic activity in pure culture. Fermentation caused a general decrease in pH from 6.6 to 3.9 after 72 h and titratable acidity increased from 0.48 to 0.79 after 72 h. Starch concentration decreased from 68 g/100 g to 37.4 g/100g. Protein and reducing sugar concentrations increased from 12.8 g/100 g to 18.5 g/100 g and from 5.3 g/100 g to 17.6 g/100 g, respectively. The types and numbers of microorganisms isolated from akamu could pose a health risk to consumers especially where this food product is used as a weaning product for infants.

Se estudiaron las propiedades microbiológicas y fisicoquímicas del akamu, un alimento fermentado a base de maíz. Se midió la población microbiológica, el pH, la acidez por titulación, azúcar y almidón durante la fermentación. La microflora inicial consistía en una mezcla heterógenea de microrganismos denominados Lactobacillus delbruecki, Lactobacillus plantarum, Lactobacillus fermentum, Lactoba-cillus amylovorus, Pseudonomas aeruginosa, Pseudomonas alkaligenes, Bacillus cereus, Bacillus licheniformis, Bacillus subtilis, Candida utilis, Candida tropicvallis, Saccharomyces cerevisiae,Aspergillus oryzae, Aspergillus niger, Penicillium citrinum, Rhizopus microsporus y Rhizopus oligosporus. Al cabo de 24 horas, las bacterias lactobacillus y mesofílicas aeróbicas formaron una parte importante de la microflora total. Las bacterias lactobacilli aumentaron a 1.6 x107 cfu/g a las 24 horas y al cabo de 72 horas a 7.1 x 10 8 cfu/g. El total de bacterias mesofílicas aeróbicas aumentaron desde 2.5 x 109 en 24 horas y a 4.2 x 10 8 a las 72 horas. El recuento de enterobacterias disminuyó de 6.3 x 103 en 24 horas a 2.5x 102 cfu/g a las 72 horas, aunque este nivel permaneció significativamente alto para un producto alimentario final. Las levaduras aumentaron en forma significativa y alcanzaron un rango de 6.8 x 105 a las 72 horas. Los recuentos de hongos disminuyeron desde 6.3 x 103 cfu/g a las 24 horas a un rango de 1.3 x 102 cfu/g a las 72 horas. Los hongos fueron responsables de la actividad amilolitica en el cultivo puro. La fermentación provocó una disminución general en el pH desde 6.6 a 3.9 a las 72 horas y la acidez por titulación aumentó a 0.48 a 0.79 a las 72 horas. La concentración de almidón disminuyó desde 68 g/100 g a 37.4 g/100 g. Las concentraciones de proteínas y azúcar reducida aumentaron desde 12.8 g/100 g a 18.5 g/100 g y desde 5.3 g/100 g a 17.6 g/100 g respectivamente. Los tipos y cantidades de microrganismos aislados del akamu suponen un riesgo sanitario para los consumidores especialmente dado que este producto es utilizado como una formula láctea para lactantes.