Coffee Science_v.18, 2023
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Resultados da Pesquisa
Item Inhibition of respiration by light in Coffea arabica(Universidade Federal de Lavras, 2023-12-29) Oliveira, Indira Pereira de; Barbosa, João Paulo Rodrigues Alves Delfino; Saleska, Scott; Pennacchi, João Paulo; Prohaska, NeillDescribing gas exchange between plants and the atmosphere is essential to improve current estimates of fluxes and carbon stocks. Light is directly related to gas exchange; when plants are under low light intensities, there is an increase in photosynthetic quantum yield and, consequently, in respiratory rate. That means there is an apparent inhibition of respiration under high light intensity, a phenomenon known as the Kok effect. Considering the effect of light and leaf age, the aim of this study was to describe the physiological responses of daytime gas exchange related to leaves of different ages in Coffea arabica L. cv. Catuaí Vermelho, seeking to identify leaf respiration inhibition by light. The experiment was conducted at the Universidade Federal de Lavras, Minas Gerais, Brazil. Leaves were measured using an infrared gas analyzer (IRGA; LI- 6400XT, LI-COR, Lincoln, NE, USA) and the fluxes were measured to create a light response curve in “in situ”, thus obtaining photosynthetic parameters, used to estimate light and dark respiration, also the rate of inhibition of leaf respiration by light throughout the leaf age. The assimilation (A_sat) and quantum efficiency did not differ among young, mature, and old leaves, showing that photosynthetic process was not affected by leaf age; however, light and dark respiration were higher in young and mature leaves than in old leaves. Inhibition of respiration by light was similar among leaf ages, assuming the occurrence of inhibition of respiration caused by light (the Kok effect).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 Caffeine and chlorogenic acid content of Coffea canephora cultivars in different environments(Universidade Federal de Lavras, 2023-11-19) Rocha, Rodrigo Barros; Alves, Enrique Anastacio; Tadeu, Hugo Cesar; Teixeira, Alexsandro Lara; Bizzo, Humberto Ribeiro; Antoniassi, Rosemar; Pacheco, Sidney; Santiago, Manuela Cristina Pessanha de AraujoCoffee plants of the Coffea canephora species are currently grown in tropical regions throughout the world, and both greater yield efficiency and greater beverage quality are important considerations. The aim of this study is to characterize the content of caffeine and of chlorogenic acids of C. canephora cultivars in different environments. According to the maturation cycle of each clone, samples of cherry coffee were collected from ten cultivars evaluated in the environments of Porto Velho, RO, Ouro Preto do Oeste, RO and Manaus, AM. These environments with contrasting characteristics represent most of the coffee fields established in the Am and Aw climate types in Latossolos Vermelhos and Latossolos Amarelos, typical of the Western Amazon. The results were analyzed considering the factorial design to quantify the effects of genotypes, of environments, and of the genotype × environment interaction (GE) on the caffeine and chlorogenic acid contents. Regardless the significant GE effects, the caffeine and chlorogenic acid content exhibited predominantly genetic control. In comparison to the caffeine, the chlorogenic acid content was more affected by the environment effects, displaying more variations in the genotypes performance across the environments. The significant positive association between the caffeine and chlorogenic acid contents favors the selection of plants that simultaneously have greater or lower contents of both traits. The selection of clone BRS3210 resulted in a selection gain of 14.99% in caffeine content, while the cultivation of the clone BRS3193 yielded a selection gain of 10.81% in chlorogenic acid content. The selection of clone BRS2299 resulted in a reduction of 21.85% in caffeine content and of 9.15% in chlorogenic acid content.Item Roasted coffee beans characterization through optoelectronic color sensing(Universidade Federal de Lavras, 2023-12-19) Vanegas-Ayala, Sebastian-Camilo; Leal-Lara, Daniel-David; Barón-Velandia, JulioThe degree of roasting of the coffee determines the physical properties of the bean which are directly represented in the quality of the coffee, to classify the coffee bean efficiently represents a challenge that has been addressed from different technological approaches with colorimeters. This research aims to simplify the identification of the roast level of ground coffee on the Agtron scale by characterizing the degree of roast using an optoelectronic color sensor and establishing a correlation between the Red, Green, and Blue (RGB) scales. This allows for the assurance of quality levels of the beans right from the roasting process. This research comprehends the collection and preparation of samples, the definition of RGB and CIE L*a*b* values, and their interpretation in the Agtron scale using the red component of the RGB scale. The results showed an efficient and accurate estimation for the roast degree of ground coffee beans (0.1371 MSE) that uses minimum processing requirements and a function to assess the intermediate values in the Agtron scale. The characterization of the roast degree of ground coffee beans using data collected from an optoelectronic color sensor through a high-precision function with a linear structure enables the description of intermediate values not fully represented on the Agtron scale. This enhances the process of identifying the roast degree, facilitating subsequent quality assurance processes by maintaining the beans at the desired roast level.Item Physical and sensorial quality of yellow caturra coffee after a carbonic maceration process(Universidade Federal de Lavras, 2023-12-15) Hernández-Alcántara, Gloria; Alarcón-Gutiérrez, Enrique; Ronzón-Soto, Samuel; García-Pérez, José AntonioHigh prices for differentiated coffees with unique flavor profiles have spurred research into processing methods to standardize coffee production and improve quality. Fermentation is a biotechnological tool that may enhance the sensory profile of coffee and boost its overall quality. Carbonic maceration, which uses constant pressure CO2, can be used as a technique to differentiate coffees. In this study, the physical and sensorial qualities of Coffea arabica (yellow caturra variety) beans, following carbonic maceration, were assessed. The experiment was carried out during the harvest 2021/22 at La Joya farm. Data were analyzed for both the physical quality of the green coffee beans and the cup quality (sensorial) based on the fermentation process and duration using ANOVA, Friedman and U Mann-Whitney tests, with a significance level of alpha = 0.05. All analyses were conducted using SPSS software version 25. The final score was influenced by both carbonic maceration and the duration of fermentation, with scores for zero-day compositions being lower than those for 5, 10 and 15 days. A significant difference in primary defects, based on the duration of fermentation, was observed. In conclusion, carbonic maceration improved both coffee qualities at day 5 compared to day zero (natural process). However, the physical quality is negatively affected after 10 and 15 days, while the sensory quality increases respectively.Item New vegetation index for monitoring coffee rust using sentinel-2 multispectral imagery(Universidade Federal de Lavras, 2023-12-29) Castro, Gabriel Dumbá Monteiro de; Vilela, Emerson Ferreira; Faria, Ana Luísa Ribeiro de; Silva, Rogério Antônio; Ferreira, Williams Pinto MarquesCoffee Rust (Hemileia vastatrix) is considered the primary coffee disease in the world. The pathogenic fungus can find favorable environmental conditions in different countries, constantly threatening coffee producers. The previous detection of the incidence of coffee rust in a region is crucial because it provides an overview of the disease’s progress aiding in coffee plantations management. The objective of this work was the development of a vegetation index for remote monitoring of coffee rust infestation. Using satellite images from the MSI/Sentinel-2 collection, the Machine Learning classifier algorithm - Random Forest, and the cloud processing platform - Google Earth Engine, the most sensitives bands in coffee rust detection were determined, namely B4 (Red), B7 (Red Edge 3) and B8A (Red Edge 4). Thus, the Triangular Vegetation Index method was used to create a new vegetative index for remote detection of coffee rust infestation on a regional scale, named Coffee Rust Detection Index (CRDI). A linear regression model was created to estimate rust infestation based on the performance of the new index. The model presented a coefficient of determination (R²) of 62.5%, and a root mean square error (RMSE) of 0.107. In addition, a comparison analysis of the new index with eight other vegetative indices commonly used in the literature was carried out. The CRDI obtained the best performance in coffee rust detection among the others. This study shows that the new index CRDI has the robustness and general capacity to be used in monitoring coffee rust infestation on a regional scale.Item Sensory and chemical analyses of spontaneously fermented coffees(Universidade Federal de Lavras, 2023-11-08) Borém, Flávio Meira; Alves, Ana Paula de Carvalho; Santos, Cláudia Mendes dos; Haeberlin, Luana; Salvio, Luís Gustavo AmaralCoffee fermentation has emerged as an innovative post-harvest process in recent years. The effectiveness of this process is in conferring sensory notes to the coffee that would please the consumer and allow for the positive differentiation of the coffees. This is achieved by monitoring the different parameters of the procedure of coffee fermentation. In this regard, the present study aimed to conduct a natural fermentation of the coffee fruit for up to 96 hours followed by the sensory (sensory characteristics for aroma, flavor, acidity, body and overall score of the 0 to 100) and chemical analyses (bioactive compounds, volatiles, organics, and fatty acids) to evaluate the influence of fermentation on sensory quality and on chemical compounds. The coffee (Coffeea arabica L.) samples for the study were collected from Presidente Olegário – MG (Harvest 2018/19) in the cerrado of Minas Gerais. The effects of fermentation and fermentation duration on the sensory quality and chemistry of coffee were evaluated. It was observed that after 48 h of fermentation, significant sensorial differentiation occurs, including an increase of the approximately two points in the final grade. In addition, time was revealed as the most relevant factor in the chemical analyses for the categorization of samples into different groups. Accordingly, it was concluded since coffees with subjected to 48, 72, and 96 h of fermentation got higher final grades, higher levels of palmitic fatty acid and characteristic compounds of fermented coffees (1,3-dioxolane 2,4,5-trimethyl, 2-furan methanol acetate, and butanoic acid) checking out the coffees wine-like notes and sweet notes to the beverage.Item Physicochemical comparison of aqueous extracts from Peruvian coffee husks (Caturra, Catimor and Geisha) varieties(Universidade Federal de Lavras, 2023-12-19) Yance, Maciela Yoselyn Puñez; Peréz, Grover Chuquipiondo; Galdos, María Estela Ayala; Pariona-Velarde, DanielThe study aimed to determine and compare the physico-chemical characteristics of coffee husks aqueous extracts corresponding to three Peruvian varieties of Arabica coffee: Caturra, Catimor and Geisha. Each sample was dehydrated at 45 °C for 10 hours, ground, sieved and dissolved in 2.5% w/w water. Aqueous extracts were obtained and analyzed for pH, total solids (TS), whiteness index (WI), reducing sugars (RS), total phenols (TP) and reducing power (RP) for the antioxidant activity The influence of coffee varieties, particle sizes (0.097, 0.033, and 0.0139in) and extraction temperaturas (60 and 80 ºC) on the physicochemical characteristics of their corresponding extracts was determined by factorial analysis. Correlation between TP and RP was significant while RS and TP showed an inverse relationship. Cluster values indicate similarity between Geisha extracts at 60 and 80 °C and the corresponding Catimor extracts at 80 °C. Differences were observed between the Catimor extracts at 60 °C and Caturra at 60 and 80 °C. Based on these results, the extracts exhibit distinctive intrinsic characteristics. The Caturra extracts at 60 °C showed the highest antioxidant capacity, while the Catimor extracts at 60 °C or 80 °C exhibited the highest WI (water holding capacity) and pH values. Additionally, the Geisha extracts displayed the highest amount of RS (reducing sugars). These findings are of utmost significance for the development of novel products using Peruvian coffee husks, encompassing beverages, concentrated juices, and the enhancement of coffee quality offered in coffee shops. These developments can be guided by the physicochemical characteristics obtained in this study.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 Phosphorus fixation and its relationship with soils chemical properties of the coffee zone of Huila, Colombia(Universidade Federal de Lavras, 2023-11-01) Poveda, Vanessa Catalina Díaz; Sadeghian, SiavoshAdsorption is one of the critical processes in phosphorus (P) availability in plants. In the coffee crop (Coffea arabica), the highest dose of P is supplied in the vegetative phase, so its management is fundamental to guarantee the optimum growth of plants. The aim of this work was to determine the P fixation capacity and its relationship with the soil chemical properties of the Huila coffee zone, Colombian department, with the largest area planted with coffee. The adsorption isotherms were obtained by equilibrating the soil with 30mL of KH2PO4 solution dissolved in a 0.01M CaCl2.2H2O, containing concentrations of P between 50 and 4.200 mg kg-1. The P adsorption was measured for 60 soil samples collected from the five main cartographic units of the department: Campoalegre, El Recreo, La Cristalina, Saladoblanco, and San Simón. The data fitted to the linear and nonlinear Langmuir model forms. It was found that the soils of the region have a variable P fixation capacity, with values of q (adsorption at 0.2 mg L-1 in solution) between 8 and 1330 mg kg-1 and b (maximum adsorption capacity) from 117 to 3916 mg kg-1, without finding an association with the evaluated soil units. A correlation of q and b was found between Al3+, Al3+ saturation, pH, Ca2+ and Mg2+, and base saturation.