Comparison of the drying behavior of fermented cocoa ( Theobroma cacao L . ) beans dried in a cocoa house , greenhouse and mechanical oven (original) (raw)
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IJERT-A Comparative Study of Effects of Drying Methods on Quality of Cocoa Beans
International Journal of Engineering Research and Technology (IJERT), 2014
https://www.ijert.org/a-comparative-study-of-effects-of-drying-methods-on-quality-of-cocoa-beans https://www.ijert.org/research/a-comparative-study-of-effects-of-drying-methods-on-quality-of-cocoa-beans-IJERTV3IS10490.pdf The study was conducted in order to determine and compare the effects of drying methods on quality of fermented cocoa beans. Drying was carried out using two different methods namely oven drying and sun drying methods. Samples were dried at five different oven temperatures of 35 o C, 40 o C, 45 o C, 50 o C and 55 o C while the other samples were sun dried until the moisture content of the samples were reduced to 6-8 %. Each sample was replicated twice. Some quality assessments were carried out for each forced-air drying temperatures and sun drying to compare the quality of sun dried samples with the oven dried ones. The quality assessments were acetic acid level, pH, colour, free fatty acid, acid value and grading. The values obtained were used to determine better method of drying cocoa beans. It was found that the samples sun dried were better than the samples oven dried. Free fatty acid (FFA) and acetic acid levels significantly increased (P < 0.05) with increase in drying temperature while the pH level decreases significantly (P < 0.05) with increase in drying temperature.
International Journal of Innovative Research and Development, 2021
This study is all about of cocoa beans moisture content behavior and prediction, during drying and experimental determination of effective moisture diffusivity and activation energy of thin-layer. Experiments were carried out on fermented cocoa beans using an oven at 40, 45, 50, 55 and 60°C. Seven semi-empirical models based on the drying kinetics were used for the modeling. This work determined the effective moisture diffusivities and activation energy of cocoa beans using respectively a variable diffusivity model based on Fick's second diffusion law and Arrhenius standard equation. The aim was to obtain the evolution of moisture content in cocoa beans considering temperature, moisture content ratio and time. The results revealed and demonstrated the reliability of some theoretical models with natural drying for temperatures below 45 °C and others with convective hot-air drying for temperatures above 50°C. All of these models seemed to be the most appropriate for describing the type of drying of cocoa beans. Values of the apparent diffusion coefficient are between 2.33275 x 10-11 m 2 /s and 2.8561 x 10-11 m 2 /s. The effective moisture diffusivity increases as a function of the drying temperature and decreases as a function of the decrease in moisture content of the product. Values of Do and Ea were estimated respectively as 1.23 10-6 m 2 /s and 43.56 kJ/mol respectively, in accordance with material and literature. It was observed that, pH values of different cocoa beans samples were between 4.82±0.26 and 5.43±0.41.
African Journal of Food, Agriculture, Nutrition and Development, 2015
Fermentation and drying are critical to the development of flavour precursors that generate into distinctive chocolate flavour notes during industrial manufacture. These processes also lead to reduction in acidity and free fatty acids of nibs, which dictates the levels of bitterness and colour development in chocolates. This study investigated changes in nib acidity, flavour precursors (sugars concentration and proteins) and free fatty acids during drying of pulp pre-conditioned and fermented cocoa beans using a 4 x 3 full factorial experimental design with pod storage (0, 3, 7 and 10 days) and drying time (0, 3 and 6 days) as the principal factors. Non-volatile (titratable) acidity, pH, sugars (reducing, non-reducing and total sugars), changes in protein content and free fatty acids of the beans were studied using standard analytical methods. Increasing pod storage consistently increased pH of the fermented nibs at the end of drying with consequential decrease in titratable acidity...
Journal of Life Sciences
This research compares the performance of a wood-fuelled oven, a greenhouse solar dryer and open sun drying techniques for drying of fermented cocoa beans, under the same weather conditions. The tests were implemented in Bafia, in the Southwest Region of Cameroon, during the month of November 2017. Performance in drying time (number of days) and quality of the resulting beans were measured (determined using sensory measurements, sight, smell and taste). Data were also collected on the progression of weight and moisture loss in the beans during the drying process, and the ambient temperatures and relative humidity levels of the environment. Also, solar radiation levels were measured for the greenhouse solar dryer and open sun drying techniques. Results showed that during dry weather conditions the wood-fuelled oven was the fastest drying method (1 day), followed by open sun drying (4 days) and the greenhouse solar dryer (5 days). The quality of beans produced through open sun drying and in the greenhouse solar dryer had a good colour, and a pleasant chocolate smell and taste. However, the beans from the wood-fuelled oven had an overly dark colour and their smell and taste were smoky due to contamination by smoke from the oven.
A Review of Cocoa Drying Technologies and the Effect on Bean Quality Parameters
International Journal of Food Science, 2020
Considering drying as a key farm-based, quality determining unit operation in the cocoa processing chain, this paper reviews recent studies in the drying methods and quality parameters of cocoa beans. Open sun, solar, oven, microwave, and freeze drying methods have been investigated at various levels in the drying of cocoa beans with objectives to improve the drying properties and final quality of cocoa beans. While an open sun dryer employs natural passive mechanisms, the solar drying methods can employ a combination of passive and active mechanisms. The oven, microwave, and freeze drying methods are fully active requiring electrical energy inputs. To improve drying rates in the open sun method, dryer materials and location of drying trays are the parameters optimized since the drying temperature depends on solar intensity. For solar dryers, materials, angles of elevation, heaters, and fans are manipulated to optimize energy absorption and drying parameters. For the oven and microw...
On the effects of forced air drying on cocoa quality
Journal of Food Engineering, 1995
Experiments were carried out to investigate the effects offorced air drying and intermittent resting on the fundamental drying mechanism of fermented cocoa beans, and the quality characteristics of the resulting ruw cocoa Two temperature, three relutive humidity and three resting regimes were investigated, at a constant airflow rate of 0.2 m s-I in a computerinstrumented drying apparatus which permitted continuous monitoring of drying air condition and sample weight. The results indicate that after nn initial warm-up and surfuce drying period of very short duration, forced air drying of cocou beuns involves u succession of falling rate periods, the number of which appears to depend on drying temperature and post-rest moisture content if the beans are subjected to intermittent resting. For continuous drying, u critical trunsitional moisture content of 70% dry basis was observed at both high (CiOOC) and low (40°C) temperature, while a further trunsition ut 30% dry basis wus onl_y noted at the lower temperuture. Quality assessment of the dried cocoa beans showed that best results were obtained from drying at low temperature or intermittent resting of the beans during high temperature drying, though the exact resting sequence needs further investigation. However, continuous drying at u high tempemture of 60°C r&s not udversely uflect cocoa quality. Similarly, removal of the mucilage coatingfiom the fermented beans prior to drying has no adverse affect.
Asian Journal of Research in Agriculture and Forestry
In order to prevent microbial spoilage and degradation responses during storage, agricultural products are typically dried to eliminate moisture from them. The removal of moisture is required for the preservation of this substance (drying). Under- or over-drying a product might result in loss through product damage. This work therefore focuses on the drying of two major crops grown by local farmers and agricultural companies; Musa paradisiaca and Theobroma cacao, obtained from a local farmer within Auchi, Edo state. The drying characteristics, including moisture content, moisture loss, and drying rates, were examined experimentally in this study at the university laboratory and Pax Herbal Clinic & Research Laboratories Ltd. This was obtained with the use of a locally fabricated cross and through circulation dryer for drying and a moisture analyzer to obtain moisture contents while taking into account temperature ranges between 40 and 80°C and time intervals from 5 to 40 minutes. The...
Cocoa Bean (Theobroma cacao L.)Drying Kinetics
Chilean journal of agricultural research, 2010
Cocoa (Theobroma cacao L.) is widely produced in West Africa and South America and is a great economic tree crop, with so many industrial uses. In this work, the experimental drying kinetics of foreign species was investigated, and the experiments were carried out under isothermal conditions, using heated batch drier at 55, 70 and 81 ºC. The moisture ratio data obtained from change of moisture content with the drying time was fit to two thin layer drying model with good results. A faster drying process was observed at a higher drying temperature resulting in higher drying rates which is advantageous when evaluating costs. Fick's second law of diffusion was used to predict effective diffusivity using experimental data assuming that the variation of diffusivity with temperature can be expressed by an Arrhenius type function, and the values of diffusivity obtained ranged from 6.137 x 10-10 to 2.1855 x 10-9 m 2 s-1 for the temperature used. The Arrhenius constant (D) is predicted at 8.64 x 10-4 m 2 s-1 while the activation energy was predicted at 39.94 kJ mol-1 .
Drying of Cocoa Beans by Using Different Techniques
2017
Drying methods such as Tray dryer, solar cabinet dryer, Microwave oven and OYSD were used. Studies were undertaken to determine the effect of different drying methods on moisture content, drying time and quality. Experiments were conducted to determine most effective method of drying for suggesting to farmers. The results were analyzed to arrive at the most effective drying method. Based on experimental results, it was found that the time taken for drying of cocoa beans from an initial moisture content of 49.35%(w.b) to a final moisture content of 6.36 % (w.b) varied considerably right from 0.4 hours for microwave drying to 30 hours in OYSD. The time taken for drying in solar cabinet dryer and tray dryer was 16 h, 8 h respectively. The time taken in Tray drier was less for drying and there is a saving about 22 h of drying time as compared to OYSD. There is a saving about 14 h of drying time in solar cabinet dryer as compared to OYSD besides producing a better quality cocoa bean powd...