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Impact of Slow Drying in a Cold Room on Coffee Sensory, Chemical, and Physical Properties
(Associação Brasileira de Engenharia Agrícola, 2024-04-26) Jordan, Rodrigo A.; Oliveira, Fabrício C. de; Argandoña, Eliana J. S.; Motomiya, Anamari V. A.; Santos, Rodrigo C.
This study aimed to evaluate the duplicity and synergism of slow drying and storage processes at low temperatures, using a refrigerated room under suitable conditions for coffee fruit just after harvest. A cold room was prepared to receive and store coffee fruit in bulk directly from the field, perform slow drying, and maintain water content at approximately 12% during three months of storage. The room operated at temperatures between 7 and 14 ºC and relative humidity between 37 and 41%. The coffee variety used was the Conilon Yellow 62. The initial water content reduction period from 54% (wb) to 12% (wb) was two months. For comparison, coffee harvested from the same batch was dried on a covered suspended bed. Results showed that the coffee dried and stored in the cold room received a sensory score of 86.41, while that dried on a suspended bed obtained a sensory score of 84.16. Moreover, the coffee dried and stored in the cold room had a higher energy content. Colorimetric analysis showed that the dried grains stored in the cold room had a reduction in the "a" coordinate, indicating an approximation to the green color. The cold room also allowed for extended storage of the coffee grains.
Influence of hulling and storage conditions on maintaining coffee quality
(Academia Brasileira de Ciências, 2023-12-11) Abreu, Giselle F.; Rosa, Sttela D.V.F.; Coelho, Stefânia V.B.; Pereira, Cristiane C.; Malta, Marcelo R.; Fantazzini, Tatiana B.; Vilela, Amanda L.
Storage is important in the coffee post-harvest. Determining the maximum period that coffee can remain storaged is important aiming to reduce losses in quality and, consequently, allow the producer to achieve maximum profitability. The aim was to determine the suitable storage period for natural and fully washed coffees, under different conditions. Beans were dried to 11% moisture content after dry processing (natural coffee, dry cherry coffee) and wet processing (parchment coffee, fully washed). Before storage, part of the coffee was hulled and part was not. The coffee was stored under refrigerated air (10ºC and 50% relative humidity) or in an environment at 25ºC. In the periods of 0, 3, 6, and 12 months, samples were taken for sensory, electrical conductivity and tetrazolium evaluation. Refrigerated environment favors conservation of sensory and physiological quality of the natural hulled coffee beans and fully washed coffee. Hulled beans of natural and fully washed coffee stored under refrigerated conditions have the initial quality conserved for up to 12 months and in non-controlled environmental, for up to 3 months. Mechanical damage caused by hulling, associated with the lack of tissue fruit parts, contributes to reduction hulled coffee quality in storage, regardless of the processing.
Fermented natural coffee followed by pulping: Analysis of the initial sensory quality and after six months of storage
(Universidade Federal de Lavras, 2023-09-01) Salvio, Luís Gustavo Amaral; Cirillo, Marcelo Ângelo; Borém, Flávio Meira; Alves, Ana Paula de Carvalho; Palumbo, Juliana Maria Campos; Santos, Cláudia Mendes dos; Haeberlin, Luana; Schwan, Rosane Freitas; Nakajima, Makoto; Sugino, Ryosuke
In recent years, different methods of fermentation have emerged for coffee, with the intention of adding complexity to its flavor. To be able to clearly identify the information from sensory analysis, tools capable of detecting small differences are needed. One such tool is multiple factor analysis (MFA). Thus, the objective of this experiment was to evaluate the effects of fermentation time and storage on the quality of sensory attributes using MFA. The coffee (Coffea arabica L.) samples collected for the study were from the Serra da Mantiqueira region – Brazil. In the present study, two natural coffee fermentation methods were evaluated, one using natural coffee microbiota (NF) and the other using a starter culture (Y), along with different times of anaerobic fermentation (0, 24, 48, 72, and 96h), followed by the pulping of the samples without the use of water. Sensory analysis of fermented coffee samples was performed immediately after drying and after six months of storage in permeable packaging in a refrigerated environment. Thus, the experiment was conducted in an intirely randomized design with a 2 x 5 x 2 factorial scheme (2 fermentation treatments; 5 fermentation times; 2 storage times). The highest scores and the attributes described in higher quality coffees, such as sweetness, acidity, and aftertaste, were attributed to coffees fermented for 96 hours. Results indicated that inoculation of the yeast Saccharomyces cerevisiae CCMA 0543 was responsible for maintaining the sensory qualities of the coffee fermented for 96 hours after 6 months of storage.
Analysis and technical optimization of processing condition for better quality of robusta coffee production
(Universidade Federal de Lavras, 2023-06-06) Ahmad, Usman; Sa’diyah, Khalimatus; Sathivel, Subramaniam
The wet processing of robusta coffee starts with harvesting coffee cherries, followed by sorting the cherries, pulping, fermentation, washing, drying, hard skin hulling, bean sorting, and packaging. Soaking fruit before pulping is an alternative for coffee farmers to delay the pulping process if time does not allow it. The fermentation process aims to remove mucus that is firmly attached to the hard skin. The addition of L. casei microbes can accelerate the process but affect the final taste. The study aimed to optimize the duration of soaking and fermentation processes for obtaining coffee beans with a minimum number of unpeeled beans, minimum partially black bean value, maximum taste quality, and to identify volatile components that play a role in forming the best steeping aroma after the coffee beans are roasted, ground and brewed. Experiments and data analysis were carried out using the Response Surface Method design. The optimization results showed that 24 hours of soaking and 24 hours of fermentation were the optimum treatment based on the criteria for unpeeled beans response, partially black bean value, and total taste score with a desirability value of 0.721. The identified volatile compounds (43) include 9 aldehyde group compounds, 3 alcohols, 4 furans, 5 heterocyclic N, 6 ketones, 1 organic acid, 3 phenols, 10 pyrazines, and 2 thiols. The spicy and chocolaty aroma produced was also the highest among treatments, namely 8.98% and 7.74%. The treatment without soaking and fermentation had the highest percentages of caramelly and nutty areas, namely 23.14% and 21.35%, respectively.
Evaluation of the behavior of coffee stored in cooled and natural environments
(Universidade Federal de Lavras, 2023-01-11) Andrade, Ednilton Tavares de; Rezende, Renan Pereira; Borém, Flávio Meira; Rosa, Sttela Dellyzete Veiga Franco da; Rios, Paula de Almeida; Oliveira, Filipe da Silva de
The market value of coffee is strongly influenced by loss of quality, which makes storage one of the main steps in the entire production chain. The finite element method (FEM) and computational fluid dynamics (CFD) are numerical and computational techniques that facilitate the simulation of agricultural product storage systems. Computational modeling satisfactorily represents real experimentation, simplifies decision-making, and reduces costs. This study aimed to analyze mocha coffee storage for 6 months in a cooled environment with temperatures between 15 and 18 °C and in a natural environment. The water content, bulk density, specific heat, thermal conductivity, and thermal diffusivity were determined and colorimetry and sensory analysis were applied to compare initial and final samples of the product after storage. It was found that the water content and specific heat were the only properties that presented significant changes. Through sensory analysis, it was observed that the quality of the coffee was the same for both systems. A computational model was developed to simulate the heat transfer process during storage. The comparison of the simulation results with the experimental results for the temperature distribution in the grain mass showed overall mean relative errors of 2.34% for the natural environment and 5.74% for the cooled environment.
Effects of post-harvest process on volatile - sensory profile for coffee in Colombia
(Universidade Federal de Lavras, 2022-12-28) Florez Arenas, Albeiro; Hincapie, Andres Mauricio Villegas; Ocampo, Gonzalo Taborda
The coffee fermentation process has been established as a determining stage regarding its quality and aroma. The objective of this study was to evaluate the differences that exist between five fermentation processes and within each process (at different fermentation times) based on their volatile and sensory profile. The processes evaluated were dry or natural (NA), semi-dry or honey (HO), and three variations of the wet process, called: conventional aerobic (AC), aerobic with previous fermentation in cherry (AFC) and anaerobic with previous fermentation in cherry (ANFC). The NA process obtained the highest score in the sensory profile and statistically different from the other processes. The volatile profile was determined by headspace solid phase micro-extraction (HS-SPME) and gas chromatography coupled to mass spectrometry (GC-MS). 51 volatile organic compounds (VOCs) were tentatively identified. The main chemical families that allowed differentiating between groups of processes were ketones and pyrroles, and the VOCs that mainly contribute to differentiate between process or groups of processes are: ethanone, 1-(1H-pyrrol-2-yl)-, 2,5-dimethylpyrazine, 2-furanmethanol, 4-vinylguayacol, 2-methylfuran, 2- butanone, 2,3-dimethylpyrazine, acetylpyrazine, 1- (2-furanylmethyl) -1H-pyrrole and 2,2'-bifuran. Within each fermentation process (between treatments) no differences were found from the final score of the sensory analysis, but differences were found from volatile profile.
Determinação do teor de água de sementes de café empregando o método da capacitância em radiofreqüências
(Associação Brasileira de Tecnologia de Sementes, 2007-09-27) Berbet, Pedro Amorim; Molina, Marília Amorim Berbet; Carlesso, Vinicius Oliveira; Oliveira, Márcia Terezinha Ramos
O desenvolvimento de modelos matemáticos que correlacionem a permissividade elétrica relativa épsilon' e o fator de perda dielétrica épsilon" à quantidade de água presente em amostras de sementes é um passo fundamental no desenvolvimento de medidores em linha do teor de água que possam ser empregados no controle automático de processos como colheita, secagem e aeração. Esse trabalho consistiu na avaliação de três modelos dielétricos para determinação do teor de água de sementes de café, sem a influência do fluxo de massa. Foram utilizadas amostras das variedades Catuaí Amarelo, Catuaí Vermelho e Mundo Novo, com teores de água entre 11 e 23% b.u. e massa específica aparente no intervalo 326 kg m-3 < r < 455 kg m-3. Dos modelos obtidos, apenas aquele que utiliza a medição simultânea de épsilon' e épsilon", a 0,5 e 5,0 MHz, permite estimar o teor de água de sementes de café com o grau de acurácia desejado. Os erros padrão de calibração e predição foram de 1,3 e 1,2 pontos percentuais, respectivamente.
Armazenabilidade de sementes de cafeeiro colhidas em diferentes estádios de maturação e submetidas a diferentes métodos de secagem
(Associação Brasileira de Tecnologia de Sementes, 2007-05-22) Veiga, André Delly; Guimarães, Renato Mendes; Rosa, Sttela Dellyzete Veiga Franco da; Von Pinho, Édila Vilela de Resende; Silva, Luiz Hildebrando de Castro e; Veiga, Adriano Delly
O momento da colheita e os métodos de secagem podem influenciar a qualidade das sementes de cafeeiro durante o armazenamento. Este trabalho foi realizado com o objetivo de avaliar os efeitos do estádio de maturação e do método de secagem sobre a qualidade fisiológica e a armazenabilidade de sementes de cafeeiro. Os ensaios foram realizados nos Laboratórios de Análise de Sementes e de Técnicas Moleculares do Departamento de Agricultura da UFLA. Os frutos do cultivar Rubi foram colhidos, despolpados, e as sementes lavadas e deixadas sobre papel para retirada da água superficial. As sementes nos estádios verde cana e cereja foram submetidas à secagem convencional (à sombra) e à secagem em secador estacionário sob temperatura de 35ºC. Como testemunha foram analisadas sementes sem secagem. As avaliações foram feitas imediatamente após os tratamentos de secagem e após 4 e 8 meses de armazenamento. As sementes foram armazenadas a 10ºC em sacos plásticos impermeáveis. Foram realizados os testes de germinação, de protrusão radicular, de matéria seca de plântulas, de índice de velocidade de emergência, de condutividade elétrica, além de análises eletroforéticas de proteínas resistentes ao calor e da quantificação da atividade da enzima endo-ß-mananase. O delineamento foi inteiramente ao acaso em esquema fatorial dois (estádios de maturação) x três (métodos de secagem) x três (tempos de armazenamento), com quatro repetições. Sementes de cafeeiro colhidas no estádio cereja têm maior potencial de armazenamento que no estádio verde cana. Ocorre redução de germinação e vigor nas sementes de cafeeiro colhidas no estádio verde cana, quando submetidas à secagem rápida. A presença ou intensidade de bandas de proteínas resistentes ao calor está associada à secagem das sementes. Ocorre maior atividade da enzima endo-ß-mananase em sementes colhidas no estádio cereja que no estádio verde-cana. Ocorre aumento da atividade da enzima endo-ß-mananase durante o armazenamento.
Protein profile in arabica coffee seeds in electrophoresis gel: importance of freeze-drying
(Associação Brasileira de Tecnologia de Sementes - ABRATES, 2022-05-13) Fávaris, Nathália Aparecida Bragança; Rosa, Sttela Dellyzete Veiga Franco da; Figueiredo, Madeleine Alves de; Coelho, Stefânia Vilas Boas; Vilela, Ana Luiza de Oliveira; Padilha, Lilian
Coffee seeds are sensitive to desiccation and are used or stored with different moisture content values, which may affect the results of quality assessment. The aim of this study was to evaluate the changes in protein profile in electrophoresis gel in coffee seeds with different moisture content values under freeze-drying and without freeze-drying. Two lots of arabica coffee seeds were used, one of newly-harvested seeds and another of stored seeds. The seeds were dried to the moisture content values of 12, 15, 20, 25, 30, 35, and 40%. The physiological quality of the seeds was assessed through the germination test, electrical conductivity, and the profiles of the enzymes SOD, CAT, PO, GOT, MDH, and EST and of heat-resistant proteins. In general, there is an effect on expression of these enzymes in accordance with the presence of free water in the seeds. Moist seeds have little to no enzyme expression. The freeze-drying process allows preservation of coffee seed quality and does not change the functionality of the enzymes studied. The isoenzyme profiles of the antioxidant process in arabica coffee seeds are affected by the initial moisture content of the seeds. The freeze-drying process of the seeds ensures greater sensitivity in detection of the expression of these isoenzymes.
Trolox equivalent antioxidant capacity of Coffea arabica L. seeds
(Editora UFLA, 2022-08-08) Ferreira, Iara Alves; Fávaris, Nathália Aparecida Bragança; Rosa, Sttela Dellyzete Veiga Franco da; Coelho, Stefânia Vilas Boas; Ricaldoni, Marcela Andreotti; Costa, Marina Chagas
The causes of the low desiccation tolerance and low longevity of coffee seeds have not yet been fully elucidated, and a full understanding of their complex physiology is of great interest. Among several alternatives, the loss of antioxidant capacity in seeds may be related to their rapid loss in quality during storage. The objective of this study was to determine the total antioxidant capacity of coffee harvested at different ripeness stages before and after the storage of seeds with different water contents and to relate antioxidant capacity to physiological quality. Seeds in the greenish-yellow or cherry stages, recently harvested or stored for nine months at 10 °C with 40, 30, 20 and 12% water content (wet basis - wb), were submitted to physiological and biochemical quality evaluations, and the Trolox equivalent antioxidant capacity (TEAC) was determined. The germination and root protrusion of coffee seeds from greenish-yellow and cherry fruits were not affected by drying, but seeds harvested at physiological maturity had greater vigor when the moisture content was lower. The quality of coffee seeds decreased during storage, and this decrease was greater in seeds stored with higher water contents. Coffee seeds in the greenish-yellow stage had a higher antioxidant capacity than those in the cherry stage when recently harvested, but there was a substantial reduction in this capacity during storage at both maturation stages. Coffee seed deterioration is related to a reduction in antioxidant capacity, and the isoenzymatic profiles of the antioxidant process are little affected by the seed maturation stage. The deterioration of coffee seeds during storage is related to a reduction in their total antioxidant capacity, regardless of their maturation stage, being more pronounced in the greenish-yellow stage

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