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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352
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Item Photovoltaic plant to supply energy for an electric coffee dryer - energy costs and compensation(Associação Brasileira de Engenharia Agrícola, 2023-11) Konopatzki, Evandro A.; Oliveira, Cristiane L. de; Marangoni, Filipe; Edwiges, Thiago; Christ, DivairIn this work, we sought to minimize electricity costs in the coffee bean drying process by carrying out the theoretical sizing of the economic viability of the Photovoltaic Power plant (PVP) ongrid used to supply a Dryer Unit (DU). The methodology consisted of adequate sizing of a PVP generation plant to promote the electric energy balance. It used economic indicators such as internal rate of return, discounted payback, and net present value. Two scenarios were considered: a pessimistic with DU use on-peak period; and an optimistic with full use of the DU during the off-peak period. It was considered local electricity tariff values, and the results indicated the economic feasibility for the PVP installation also the feasibility of the dryer use in both scenarios, there are no restrictions on operating hours. It can be concluded that it is essential to understand the Brazilian electricity bill legislation because only in this way is it possible to properly develop the on-grid photovoltaic power plant projects. The technical and economic parameters are inseparable and indicated that the electricity tariff should not exceed US$ 0.22 (kWh) -1 to ensure the photovoltaic power plants installation viability to supply DUs that remain in operation during on-peak periods.Item Arabica coffee flow properties assessed using different roasts and particle sizes during storage(Instituto de Tecnologia de Alimentos – ITAL, 2022-02-18) Oliveira, Gabriel Henrique Horta de; Corrêa, Paulo Cesar; Oliveira, Ana Paula Lelis Rodrigues de; Vargas-Elías, Guillermo Asdrúbal; Calil Júnior, CarlitoFlowability of agricultural products is an important factor to be considered at post-harvest, thus impacting directly on number of operations and the design of machinery. This study aimed to evaluate and determine the K coefficient and flow properties as a function of different levels of roasting, grain size, temperature and storage. Coffee beans were roasted at medium light and moderately dark, then ground at fine, medium and coarse sizes. An additional coffee lot was not ground. Samples were stored at 10 ºC and 30 ºC and analyzed during storage (0, 30, 60, 120 and 180 days), regarding internal and external friction coefficients, angle of internal friction, effective angle of internal friction, wall friction angle (concrete, rough steel and wood) and lateral pressure coefficient (K coefficient). Angle of internal friction varied significantly due to particle size and roast degree. Moderately dark roast with fine particle size led to higher values (about 29.5 º) of wall friction angle. The wood sample was the material with the highest values of wall friction angle, followed by the concrete and steel samples, when compared at the same storage temperature, roast degree and particle size. Whole coffee was classified as free-flowing. Fine particle size leads to cohesive flow characteristic, according to the flow function. Coffee roasted at medium light, kept whole requires storage facilities with higher pressure support, accordingly to the K coefficient values.Item Green and roasted arabica coffees differentiated by ripeness, process and cup quality via electrospray ionization mass spectrometry fingerprinting(Sociedade Brasileira de Química, 2009) Amorim, Ana Carolina L.; Hovell, Ana Maria C.; Pinto, Angelo C.; Eberlin, Marcos N.; Arruda, Neusa P.; Pereira, Elenilda J.; Bizzo, Humberto R.; Catharino, Rodrigo R.; Morais Filho, Zenildo B.; Rezende, Claudia M.Direct infusion electrospray ionization mass spectrometry in both the negative ESI(-)-MS and positive ESI(+)-MS ion modes are investigated to differentiate green and roasted Arabica coffees with different stages of ripeness (green, ripe and overripe), post-harvesting process (dry, wet and semi-wet) and coffees with diferente cup qualities. In the ESI(-)-MS of green coffees, ions from deprotonated fatty acids and chlorogenic acids are the most important for ripeness discrimination. In the ESI(+)-MS, maturity is differentiated by ions from protonated caffeine, chlorogenic acids and K+ adducts of fatty acids. To differentiate between post-harvesting process in both ionization modes, ions from fatty acids, chlorogenic acids, sugars and carboxylic acids generated in the fermentation process are the most representative. Roasted Arabica coffees are also well discriminated: in the ESI(-)-MS, ions from chlorogenic acids and short-chain organic acids derived from sugars are important. In the ESI(+)-MS, discrimination are mainly performed by low m/z ions such as protonated pyridine and alkylpiridines formed via trigonelline degradation. Both ESI(+)-MS and ESI(-)-MS are able to differentiate cup quality for Arabica roasted coffees and the ions used to perform discrimination are the same ones described in ripeness and post-harvesting processes.Item Efect of lnf (cna - cnb) enzyme complex in the drying process and the coffee quality(Editora UFLA, 2020) Santos, Douglas Freitas; Franco Junior, Kleso Silva; Silva, Carlos Henrique da; Silva Neto, José Francisco da; Paiva, Leandro Carlos; Brigante, Giselle PradoThe world demand for quality coffee is growing and the market is increasingly demanding for sustainable practices, leading coffee growers to search for new coffee processing processes always aiming for maximum quality. The objective of this work was to verify the benefits of using the LNF CNA – CNB enzyme complex in the postharvest process, in order to compare the results of drying time and the final beverage quality of the product. The research was carried out at Fazenda Iracema, municipality of Machado - Minas Gerais, with mechanically harvested coffees from the cultivar Mundo Novo, with 80% maturation, and the treatments were: natural and washed coffee, with and without application of enzymatic complex and drying in suspended, concrete and mixed courtyards (initially in the yard and finished in rotary dryers), the enzyme complex dosage was 1 ml CNB + 2.5 ml CNA per liter of water, applied to 60 liters of coffee. The experimental design was in randomized blocks, in a 2 x 2 x 3 factorial scheme (2- types of “washed or natural” processing; 2- with and without enzymatic application; 3 - “suspended, concrete and drying” drying forms), with 4 repetitions per treatment, totaling 48 experimental plots. The coffees were dried to 11.5% humidity and evaluated by the SCAA. It was concluded that the use of LNF (CNA - CNB) enzymatic complex in the coffee drying process did not influence the final drying time results, nor did it influence the coffee beverage aroma attributes. The drying forms directly influence the drying time.Item Effect of induced biological fermentations on coffee sensory quality(Editora UFLA, 2019-10) Cândido, Talita Amparo Tranches; Sepini, Pedro Pereira; Abrão, Polyana de Faria Cardoso; Oliveira, Reginaldo de; Campos, Kátia Alves; Paiva, Leandro CarlosQuality coffee consumption has been gradually increasing and having an impact on coffee prices not only for domestic but also for the foreign market. Different processing (preparation) methods of coffee will directly influence the quality of the final product. Taking this into consideration, this study aimed at evaluating sensory attributes of coffee submitted to biological fermentation. The experiment was carried out in a block design with 4 x 4 +1 factorial scheme. We evaluated the sensory attributes of coffee submitted to different fermentation treatments and times (8, 16, 24, 32 hours submerged in water, water + Saccharomyces cerevisiae, water + Saccharomyces bayanus, and water + Lactococcus lactis).