Use of monosodium glutamate in foods: the good, the bad, and the controversial side / Uso de glutamato monossódico em alimentos: o bom, o mau e o lado controverso

Introduction: Monosodium glutamate (MSG) is known as a flavor-enhancing compound and also the fifth basic taste (umami). About the safety of using MSG as a food additive, some studies show indications that there is no threat and others showthe opposite. There is no consensus about the advantages and disadvantages of using MSG. Objective: To systematically review studies in the international literature on the knowledge of the pros and cons of using glutamate in food. Methods: Systematic review of studies published in journals indexed in ScienceDirect and PubMed databases. Articles published until 2020 were included. The aspects involving the advantages and disadvantages were discussed, as well as the health risks related to the MSG intake from diet. Results: The revised studies showed that MSG can reduce the amount of sodium in foods without modifying flavor. Although authorities indicate that MSG is safe for human consumption, some studies highlight that health risk is real. The use of MSG is still controversial because there are some misunderstandings in the applied amounts of MSG absorption and metabolism. Conclusion: MSG is widely applied in industrial and homemade food. The need for further studies is crucial, and aspects such as metabolism and amounts of MSG effectively consumed must be better evaluated.

Surface response methodology for the optimization of lipase production under submerged fermentation by filamentous fungi

Abstract A Plackett–Burman Factorial Design of 16 experiments was conducted to assess the influence of nine factors on the production of lipases by filamentous fungi. The factors investigated were bran type (used as the main carbon source), nitrogen source, nitrogen source concentration, inducer, inducer concentration, fungal strain (Aspergillus niger or Aspergillus flavus were selected as good lipase producers via submerged fermentation), pH and agitation. The concentration of the yeast extract and soybean oil and the pH had a significant effect (p < 0.05) on lipase production and were consecutively studied through a Full Factorial Design 23, with the concentration of yeast extract and pH being significant (p < 0.05). These variables were optimized using a central composite design, obtaining maximum lipolytic activities with the use of 45 g/L of yeast extract and pH 7.15. The statistical model showed a 94.12% correlation with the experimental data.

Potencial amilolítico do grão de milho maltado no processo de sacarificação do mesmo cereal / Amylolytic potential of maize malt in the process of sacarification of the same cereal

Objetivou-se avaliar o potencial de sacarificação do malte de milho para produção de álcool deste cereal. Para tal, foi realizada germinação do grão de milho a 20 ºC por 5 dias. O potencial amilolítico do malte de milho foi otimizado por meio de um PlanejamentoFatorial Completo 22 com 3 pontos centrais, sendo as variáveis de estudo a temperatura de incubação e concentração de substrato [S]. A sacarificação foi realizada por meio de um Planejamento de Mistura com três pontos centrais, sendo as variáveis de estudo a concentração de malte e concentração de substrato, durante 6 horas. A fermentação foi conduzida com a melhor condição de sacarificação, em reator de 5 L e volume útil de 2 L. O pH foi fixado em 4,5-5. O Brix foi acertado para o valor de 14º. O mosto hidrolisado foi esterilizado e inoculado com 5,0 g.L-1 de Saccharomyces cerevisiae proveniente de fermento comercial liofilizado. O sistema foi submetido a 2 horas de aeração inicial (170 LO2.h -1) e mantido na temperatura de 30 °C. Durante o processo de fermentação, foram realizadas determinações da concentração de células (g.L-1), açúcares redutores (mg.mL-1) e álcool (g.L-1). As variáveis temperatura de incubação e concentração de substrato foram significativos (p< 0,05) na condição de estudo de 20 % de substrato e incubação a 70 °C. Os experimentos centrais com 50 % de malte apresentaram os melhores parâmetros cinéticos com taxa volumétrica de formação de produto em etanol de 2,81 getanol.L-1.h-1 que corresponde a 8,0 ºGL e conversão de substrato em células 0,127 gcélula.gglicose-1.

The aim of this research was the production of maize malt and the evaluation of its use for alcohol production. The maize grain was allowed to germinate at 20°C for five days. The amylolitic potential of malt was optimized through a Complete Factorial Planning 22 with three central points, where the study variables were the temperature of incubation and the substrate concentration [S]. The sacarification was performed through a Planning of Mixture with three central points, where the study variables were the malt concentration and [S] during six 6 hours. The fermentation was carried out using the best sacarification condition, in a five-liter reactor and a two-liter working volume. The pH was maintained at 4.5 – 5.0. The Brix was corrected to 14º. The sterile hydrolyzedproduct was inoculated with 5.0 g.L-1 Saccharomyces cerevisiae. The system was submitted to two hours of initial aeration (170 LO2.h-1) and kept at 30°C. During the fermentation process, analyses were made to determine the cell concentrations (g.L-1), reducingsugars (mg.mL-1), alcohol (g.L-1) and °Brix. The temperature of incubation and substrate concentration were significant factors (p<0.05) in the determination of the amylolytic potential under the conditions of study utilizing 20% of substrate and incubation at 70°C. The central experiments with 50% malt presented the best kinetic parameters with a volumetric rate of ethanol formation of 2.81 gethanol.L-1.h-1, which correspond to 8.0 ºGL, and a substrate conversion in cells of 0.127gcells.gglucose -1.

Profile of the alcohols produced in fermentations with malt contaminated with trichothecenes

In order to study the influence of mycotoxins on the production of alcohols, a fermentative process on a laboratorial scale was simulated. Malt was contaminated with deoxynivalenol and T-2 in different ratios (up to 500 ppb), according to a 3² factorial design, and the alcohols obtained after the fermentation were determined through gas chromatography. The results showed that trichothecenes influenced the profile of the alcohols produced by Saccharomyces cerevisiae during the fermentative process of malt, especially the profile of methyl and isoamyl alcohols