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Item Effect of extraction processing parameters using a ribbon blender on the physicochemical properties of coffee(Universidade Federal de Lavras, 2024-07-03) Barriga, Paula Andrea Mayorga; Pardo, Ruth Yolanda Ruiz; Moreno, Fabian Leonardo MorenoIn this work, the effect of the water-coffee ratio, time, and stirring speed, on the total soluble solids, extraction rate, titratable acidity, and extraction yield was evaluated for the percolation of coffee in a horizontal ribbon blender equipment. The coffee extract was obtained in a pilot unit at a constant temperature of 85°C and varying the water-coffee ratio from 4:1 to 10:1; the stirring speed between 30 and 95 RPM and the extraction time from 10 to 60 minutes. It was determined that the water-coffee ratio was the factor that had a significant influence on all the response variables, while time and stirring were significant for the extraction rate and titratable acidity. The optimal setup among the studied conditions was using a water temperature of 85°C, a water-coffee ratio of 4:1, and a stirring speed of 66 RPM for ten minutes. At these conditions, an extract of 5.85% TDS, 14.54% as yield, an extraction rate of 654.8 g/h, and a content of 5.62 mg of CGA/mL was obtained. Hence, this study presents an alternative process to obtain coffee extract in producing soluble coffee at a low industrial scale.Item Instant coffee: Products and packaging systems characteristics(Universidade Federal de Lavras, 2023-12-15) Souza, Raquel Massulo; Moreira, Christiane Quartaroli; Alves, Rosa Maria VercelinoThe moisture gain cause instant coffee quality loss. In Brazil, these products are marketed in glass jars, with seals and screw caps, metal cans with easy-open lid and LDPE (low density polyethylene) over cap and flexible plastic packaging of multilayer film: PET (polyethylene terephthalate)/Al (aluminum) foil/LDPE. The aim of this study was to evaluate three types of instant coffees (freeze-dried, spray-dried agglomerated and powder) and their packages regarding to water activity, initial moisture, thermal analysis and moisture sorption isotherm, as well as some characteristics of the packaging systems - gas composition of the headspace, oxygen and water vapor transmission rate. All instant coffees evaluated presented similar characteristics of quality standard described in international literature. Products showed quality loss appearance with 10%-12% (d.b.) moisture content. Packaging systems presented oxygen transmission rate values greater than 1.000mL (STP)m-2.day-1 and water vapor transmission rate values less than 0.017g of water.package-1.day-1 (25°C/75%RH) and 0.048g of water.package-1.day-1 (38°C/90%RH).Item Instant coffee: Products and packaging systems characteristics(Universidade Federal de Lavras, 2023-12-15) Souza, Raquel Massulo; Moreira, Christiane Quartaroli; Alves, Rosa Maria VercelinoThe moisture gain cause instant coffee quality loss. In Brazil, these products are marketed in glass jars, with seals and screw caps, metal cans with easy-open lid and LDPE (low density polyethylene) over cap and flexible plastic packaging of multilayer film: PET (polyethylene terephthalate)/Al (aluminum) foil/LDPE. The aim of this study was to evaluate three types of instant coffees (freeze-dried, spray-dried agglomerated and powder) and their packages regarding to water activity, initial moisture, thermal analysis and moisture sorption isotherm, as well as some characteristics of the packaging systems - gas composition of the headspace, oxygen and water vapor transmission rate. All instant coffees evaluated presented similar characteristics of quality standard described in international literature. Products showed quality loss appearance with 10%-12% (d.b.) moisture content. Packaging systems presented oxygen transmission rate values greater than 1.000mL (STP)m-2.day-1 and water vapor transmission rate values less than 0.017g of water.package-1.day-1 (25°C/75%RH) and 0.048g of water.package-1.day-1 (38°C/90%RHItem Evaluation of arsenic and selenium in brazilian soluble coffee by inductively coupled plasma atomic emission spectrometry with hydride generation(Instituto de Tecnologia do Paraná - Tecpar, 2001-10) Santos, Éder José dos; Oliveira, Elisabeth deA method for the evaluation of arsenic and selenium in soluble coffee by inductively coupled plasma atomic emission spectrometry with continuous hydride generation to attend the Brazilian food legislation is described. Samples were digested with nitric acid and hydrogen peroxide in a focused microwave system. Slow heating eliminated nitric acid and selenium (VI) was reduced to selenium (IV) by addition of 6 mol/L hydrochloric acid and heating at 90°C under a reflux system. The influence of sample acidity on sensitivity was investigated. Hydrochloric acid 6 mol/L was the most suitable reaction medium. Practical detection limits of 2.0μg/L for As and 1.0μg/L for Se were achieved and attended the Brazilian food legislation. The results of recoveries on spiked samples demonstrate the reliability and accuracy of the procedure.