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URI permanente desta comunidadehttps://thoth.dti.ufv.br/handle/123456789/3352

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Resultados da Pesquisa

Agora exibindo 1 - 10 de 203
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    Fermentação controlada em biorreatores artesanais para a produção de cafés especiais
    (Editora UFLA, 2024-04-26) Reyes, Etztli Itzel Morales; González, Martín Alejandro Bolaños; Balcazar, Julian Ovidio Cucuñame; Velasco, Jesús Salazar
    A model of an artisanal bioreactor was tested for fermentations in specialty coffee production, monitoring parameters such as Brix, temperature, pH, electrical conductivity, and total dissolved solids. The results demonstrated that the bioreactor effectively controlled these parameters, ensuring consistent processes and reproducibility, as well as uniformity in the final product. Both washed coffees, one with lactic acid bacteria (LAB) inoculation and one without, were produced and evaluated using the Cup of Excellence (COE) format. The coffee without inoculation scored 84 points, while the coffee with LAB scored 85.9 points. This highlights a significant positive correlation between LAB treatment and the sensory quality of the coffee produced.
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    Consumer acceptability and fragrance quality differentiate on of Mogiana coffee types using the Check-All-That-Apply (CATA) method
    (Academia Brasileira de Ciências, 2023-06-16) Benedito, Luiza Z.; Lima, Clara Mariana G.; Pires, Fabiana C.; Amaral, Ana Elisa; Verruck, Silvani; Pereira, Rosemary G. F. A.
    Coffee, one of the most produced and consumed beverage in the world, has a range of variability in its quality. The aim of this work was to evaluate the consumer capacity to perceive the coffee quality through their fragrance and to verify the influence of previous information about quality on this perception using hedonic scale and Check All That Apply (CATA) sensory tests. The sensory tests were performed in two stages, one without and the other with quality related information of Mogiana coffee samples (Rio, Hard and Soft), and a traditional coffee sample. CATA attributes frequency of occurrence shows that samples discrimination could be done with specific attributes. For Soft coffee the attributes with more occurrence were sweet, caramel, brown sugar, and smooth. The Hard coffee sample was described by the attributes peanut, buttery, and chocolate. While for Rio coffee, the descriptive attributes most often mentioned were strong and burnt. The traditional sample stood out among consumers for its characteristics of old, medicine, sour, burnt, unpleasant and spicy. Therefore, the use of coffee powder fragrance can be alternative to differentiate the quality of the product and its function can be enhanced by passing on information on quality attributes to consumers.
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    Variability of volatile compound profiles during two coffee fermentation times in northern Peru using SPME-GC/MS
    (Instituto de Tecnologia de Alimentos – ITAL, 2023-05-15) Perez, Jhordy; Calderon, Martha Steffany; Bustamante, Danilo Edson; Caetano, Aline Camila; Mendoza, Jani Elisabet; Fernandez-Güimac, Samia Littly Jahavely
    The time of the fermentation process of coffee from northern Peru is variable (9 to 48 hours) since coffee farmers do not use standardized processes, causing a variety of coffee qualities. This study aimed to identify volatile compounds in both short (9 hours) and long (32 hours) coffee fermentation processes from coffee farms in northern Peru using Solid-Phase Microextraction-Gas Chromatography/Mass Spectrometry (SPME-GC/MS) to associate the coffee quality and diversity of volatile compounds. Sensory analyses showed that the short fermentation process (SFP) scored 77.8 ± 0.39 and had chocolate, wood, cardboard, dry, fatty and rough notes, while the long fermentation process (LFP) showed higher punctuations 85.5 ± 3.16 and citrus, fruity, floral, caramel and chocolate sensory attributes. A total of 90 compounds were found in the SFP, whereas 141 compounds were identified in the LFP. Significant differences in the relative abundance of 14 chemical compounds were reported in the SFP and LFP (p < 0.05). From these results, the presence of benzaldehyde, methional, hexanal, 2-heptanone, pentadecane, 1-butanol-3-methyl-acetate, and benzene-acetic acid ethyl ester seems to impact the quality of coffee. The analysis of similarities showed that coffee samples (5 h and 9 h) during the SFP were very variable, whereas coffee samples from LFP showed some tendency to group, which may be related to the difference in altitude and temperature in coffee farms making comparison between them difficult. In addition, this study highlights the complex relationship between coffee fermentation and flavour and the influence of several factors and variables that may affect the composition of flavour and aroma precursors in green coffee beans obtained from wet fermentation.
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    Inoculation of Saccharomyces cerevisiae with sugar cane juice as a starter culture in coffee (Coffea arabica) fermentation
    (Departamento de Engenharia Agrícola - UFCG, 2024-01) Ladino-Garzon, Wilmer L.; Barrios-Rodríguez, Yeison F.; Amorocho-Cruz, Claudia M.
    This study aims to evaluate the effect of sugarcane juice and the addition of commercial yeast Saccharomyces cerevisiae var. bayanus (≥ 1 × 1010 cfu/g) during the fermentation of coffee to the beverage’s sensory characteristics and the coffee bean’s chemical composition. A completely randomized experimental design with two replicates is carried out for four treatments, distributed as follows: i) water addition (0.78 kg), ii) sugar cane juice addition (0.78 kg), iii) sugar cane juice addition (0.78 kg) combined with yeast Oenoferm® Freddo (0.12 g) and iv) sugar cane juice addition (0.78 kg) combined with yeast Oenoferm® Color (0.12 g). After fermentation and drying, the samples were subjected to medium roasting and analyzed using infrared spectroscopy and sensory analysis according to the methodology of the Specialty Coffee Association. The implementation of organic additives directly affected the attributes and sensory notes, allowing coffee to be classified as a specialty coffee with a score above 80 points. Adding sugar cane juice or a combination of sugar cane juice and Saccharomyces cerevisiae showed promising results in improving coffee beverage quality. Additionally, chemometric analysis of the infrared spectrum showed that the chemical characteristics of roasted coffee were affected, which correlated with the sensory results. The addition of cane juice only (T2) and the Oenoferm® Freddo yeast strain (T3) presented the best sensory quality.
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    Aroma profiles and cupping characteristics of coffee beans processed by semi carbonic maceration process
    (Universidade Federal de Lavras, 2023-07-18) Jitjaroen, Wanphen; Kongngoen, Rungtiwa; Panjai, Lachinee
    The goal is to improve the flavors of Arabica coffee by combining semi-carbonic maceration (SCM) process, with enzymatic process at various lengths and temperature. Five different variations of SCM processes were investigated: pulped natural process (control); at 15 oC for 10 days (SCM-15); at 20 oC for 10 days (SCM-20); with 0.01 g.L-1 pectinases A (polygalacturonase, pectin esterase and pectin lyase) at 20 oC for 5 days (SCM-PA); and with 0.03 g.L-1 pectinases B (polygalacturonase, pectin esterase, pectin lyase and ß-glucanase) at 20 oC for 5 days (SCM-PB). The chemical composition of intact mucilage and green bean coffee were analyzed. The environments created by using SCM fermentation process at 20 oC combined with pectinase A and pectinase B produced green bean coffee with higher content of acidity and reducing sugar. The volatile compounds of roasted coffee were examined by Gas Chromatography-Mass Spectrometry (GC-MS). Fifty-one volatile compounds belonging to 12 chemical classes were identified. The different total peak area, indicates that most volatile compounds, increases during SCM, and SCM process combined with enzymatic method. The Specialty Coffee Association of America; SCAA sensory analysis was performed by trained specialty coffee judges. The final product of coffee beans, which has been treated with SCM process at 15 and 20 oC have obtained the highest score in fragrance, flavor, aftertaste, body, balance and overall impression. While the enzyme treatment has attained the highest scores in acidity. This study demonstrates that the proposed process may be useful for the improvement of the cup quality.
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    Differences in chemical characteristics due to different roasting of robusta coffee beans
    (Universidade Federal de Lavras, 2023-08-23) Ramadhani, Aji Fajar; Nisa, Fithri Choirun; Yunianta
    Roasting is a process that contributes to the formation of compounds and flavors in coffee beans. Temperature and length of time are the main factors in the roasting process. Generally, the range of temperatures and roasting times varies significantly for different varieties of coffee beans. This study aims to determine the effect of roasting on changes in the chemical characteristics of robusta coffee beans (Coffea canephora) from Sidomulyo Village. This study used different brewing methods to brew roasted robusta coffee beans with the best chemical characteristics used a factorial randomized block design with two factors: roasting temperature, which consisted of three levels (185, 190, and 195 ⁰C), and roasting time, which consisted of three levels (10, 13, and 16 minutes). The roasted coffee beans were analyzed for water content, ash content, caffeine content, total phenol, and pH. The results of this study obtained a water content value of 3.523 ± 0.129% to 1.939 ± 0.025%, ash content of 8.119 ± 0.115% to 4.315 ± 0.260%, a caffeine content of 2.494 ± 0.015% to 2.176 ± 0.021%; total phenol of 6.251 ± 0.101% to 4.334 ± 0.117%; and a pH value of 6.675±0.126 to 4.075±0.171. At this stage, the best treatment (Zeleny method) is produced by robusta coffee beans roasted at 185⁰C for 10 minutes. Robusta coffee beans with the best treatment have a moisture content of 3.523 ± 0.129%; ash content of 4.315 ± 0.260%, the caffeine content of 2.494±0.015%; total phenol of 6.251±0.101%; and a pH value of 4.075±0.171.
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    Case study of modeling covariance between external factors and sensory perception of coffee
    (Universidade Federal de Lavras, 2023-08-18) Resende, Mariana; Borém, Flávio Meira; Cirillo, Marcelo Ângelo
    Analysis and inference of sensory perceptions in coffee beverages are complex due to numerous random causes intrinsic to productivity, preparation, and especially consumer and/or taster subjectivity. In this context, latent variables often composed of a combination of other observed variables are discarded from conventional analyses. Following this argument, this study aimed to propose a model of structural equations applied to a database, geographical indication of coffees in Serra da Mantiqueira, with a methodological contribution characterized by inclusion of a treatment effect, contemplated by different altitudes at which coffees were produced. From the methodology used, a covariance structure was estimated, and used in another statistical methodology to discriminate the effects. It is concluded that the proposed model proved to be advantageous for allowing the analysis of the relationship of latent variables, production and environmental variations, which are not considered in a sensorial analysis, and showed that, in fact, they influence the sensorial perception, for the coffees produced in the Serra da Mantiqueira region. The correlation structure generated from the covariance matrix adjusted by the model resulted in estimates that could be used in other statistical methodologies more appropriate to discriminate the effects, exemplifying the use of principal components.
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    Study of variations in the roasting time of gayo arabica coffee in the drying phase
    (Universidade Federal de Lavras, 2023-06-06) Fadhil, Rahmat; Safrizal, S; Rizal, Khairul; Putra, Bambang Sukarno; Firmansyah, Juli
    Gayo Arabica coffee is a famous specialty coffee in Indonesia and abroad. Proper roasting is needed to produce high-quality coffee, including getting the desired coffee taste. This study contributes to roasting high-quality coffee, especially regarding the appropriate time variation in the drying phase. This study aims to analyze the roasting time of Gayo Arabica coffee in the drying phase based on the cupping score and sensory assessment. Coffee roasting in this study was carried out by modifying the time in the drying phase for 3:00, 4:00, and 5:00 minutes, while in the other phases (maillard and development), it was 4:00 and 3:00 minutes, respectively. The study parameters include roasting charts, roasting profiles, cupping scores by certified panelists (Q graders) and sensory assessments by panelists identified by the TOPSIS method. The TOPSIS is a decision-making method based on various alternatives that are ranked to get the best results with the highest value. The results showed that the best time treatment in the drying phase based on the cupping score was the F2 treatment as rank 1 (score 85.00), treatment F1 as rank 2 (score 83.50), and treatment F3 as rank 3 (score 81.00). Meanwhile, the sensory assessment by the panelists using the TOPSIS method showed the same thing for rank 1, namely the F2 treatment with a value of 0.88. However, it is different for rank 2, namely the F3 treatment with a value of 0.69 and ranks 3 is the F1 treatment with a value of 0.17. It can be concluded that the assessment by certified and identified panelists, who can be considered representative of consumers, show the same conclusion that coffee roasted with the best treatment in the drying phase is 4 minutes (F2).
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    Production of Coffea canephora seedlings through cuttings in a nursery and hydroponics using different containers
    (Universidade Federal de Lavras, 2023-07-19) Lima, Amador Eduardo de; Castro, Elisa de Melo; Cunha, Samuel Henrique Braga da; Guimarães, Rubens José; Chalfun, Nilton Nagib Jorge; Carvalho, Alex Mendonça de; Alves, Eduardo; Carvalho, Milene Alves Figueiredo
    The production of seedlings is a determining factor for the establishment and success of the coffee plantation. The objective of this study was to evaluate the production of Coffea canephora seedlings by cuttings in a modified hydroponic system and in a conventional nursery, using different containers. At the end of the experiment, growth (height, stem diameter, total number of pairs of leaves, leaf area, root area, dry matter weight of leaves, stem and root), physiological (chlorophyll a, b and total and stomatal conductance) and anatomical (stomatal density, functionality and opening) characteristics were analyzed. For statistical analysis, a completely randomized design (CRD) was used, with five treatments and six replications, with ten plants per plot. Seedlings produced in a modified hydroponic system using 50- and 120-cm³ tubettes show better vegetative growth and physiological characteristics compared to those produced in a nursery. Seedling management in a modified hydroponic system using 120-cm³ tubettes provides greater cutting survival percentage, number of remaining leaves and emission of shoots. In nurseries, the use of polyethylene bags provides better seedling quality and survival in relation to the use of tubettes, regardless of volume.
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    Physical and sensorial quality of arabica coffee cultivars submitted to two types of post-harvesting processing
    (Universidade Federal de Lavras, 2023-04-17) Alixandre, Ricardo Dias; Alixandre, Fabiano Tristão; Lima, Paula Aparecida Muniz de; Fornazier, Maurício José; Krohling, Cesar Abel; Amaral, José Francisco Teixeira do; Guarçoni, Rogério Carvalho; Dias, Rodrigo da Silva; Venturini, Cassio de Faria; Macette, Higor Alixandre; Zandonadi, Cecília Uliana; Viçosi, David Brunelli
    The growing demand for better quality coffees has driven changes in the coffee production chain, mainly through the adoption of new technologies and management. Thus, this work was carried out aiming to evaluate the physical and sensorial quality of Arabica coffee cultivars, submitted to natural and pulped post-harvesting processing. The experiment was carried out following a randomized block design with three replications, in a split-plot scheme, with the plots consisting of five cultivars (Catucaí 2 SL, Catucaí 24/137, Catuaí IAC 44, Arara and Acauã); and the subplots by two processes, pulped and natural cherry. The harvest was carried out manually, harvesting the cherry fruits (ripe) in a sieve. The coffees were processed by the natural and pulped cherry methods. Drying was carried out on a covered suspended terrace, until the grains reached 11% ± 1 moisture (wet basis, bu). The following evaluations were carried out: sensorial analysis of the beverage according to the SCAA methodology, analysis of grain sieves according to the Official Brazilian Coffee Classification Protocol. The results show that all evaluated cultivars have a great potential for the production of specialty coffees in that studied environment. Differences were observed between cultivars both in the sensory quality of the beverage and in the grain size. Cultivar Arara presents a general average of final beverage grade higher than the other cultivars.