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Farm to Consumer: Factors Affecting the Organoleptic Characteristics of Coffee. II: Postharvest Processing Factors 下载免费PDF全文
Ahsan Hameed Syed Ammar Hussain Muhammad Umair Ijaz Samee Ullah Imran Pasha Hafiz Ansar Rasul Suleria 《Comprehensive Reviews in Food Science and Food Safety》2018,17(5):1184-1237
The production and consumption of coffee are increasing despite the roadblocks to its agriculture and global trade. The unique, refreshing, and stimulating final cupping quality of coffee is the only reason for this rising production and consumption. Coffee quality is a multifaceted trait and is inevitably influenced by the way it is successively processed after harvesting. Reportedly, 60% of the quality attributes of coffee are governed by postharvest processing. The current review elaborates and establishes for the first time the relationship between different methods of postharvest processing of coffee and its varying organoleptic and sensory quality attributes. In view of the proven significance of each processing step, this review has been subdivided into three sections, secondary processing, primary processing, and postprocessing variables. Secondary processing addresses the immediate processing steps on the farm after harvest and storage before roasting. The primary processing section adheres specifically to roasting, grinding and brewing/extraction, topics which have been technically addressed more than any others in the literature and by industry. The postprocessing attribute section deals generally with interaction of the consumer with products of different visual appearance. Finally, there are still some bottlenecks which need to be addressed, not only to completely understand the relationship of varying postharvest processing methods with varying in‐cup quality attributes, but also to devise the next generation of coffee processing technologies. 相似文献
474.
Mutamed Ayyash Ayesha S. Al-Dhaheri Suheir Al Mahadin Jaleel Kizhakkayil Aisha Abushelaibi 《Journal of dairy science》2018,101(2):900-911
This study aimed to investigate in vitro anticancer activity by antiproliferative activity, antihypertensive activity by angiotensin-converting enzyme inhibition, antidiabetic activity by α-amylase and α-glucosidase inhibitions, and antioxidant activities of camel milk fermented with camel milk probiotic compared with fermented bovine milk. The camel milk probiotic strain Lactococcus lactis KX881782 (Lc.K782) and control Lactobacillus acidophilus DSM9126 (La.DSM) were used to prepare fermented camel and bovine milks separately. The proteolytic activities of water-soluble extract (WSE) in all fermented camel milk were higher than those in fermented bovine milk. The α-glucosidase inhibitions in both milk types fermented by Lc.K782 ranged from 30 to 40%. Camel milk fermented by Lc.K782 had the highest antioxidant activity by 2,2'-azino-bis(3-ethylbenzo-thiazoline-6-sulphonic acid). The highest angiotensin-converting enzyme inhibition of WSE in camel milk fermented by Lc.K782 was >80%. The proliferations of Caco-2, MCF-7, and HELA cells were more inhibited when treated with WSE of fermented camel milk extracts. 相似文献
475.
Iqra Hameed Bing Liu Lei Li Xiao Qiang Liu Xiang Ming Chen 《International Journal of Applied Ceramic Technology》2019,16(5):2040-2046
(Sr1-xCax)2TiO4 ceramics (0 ≤ x ≤ 0.15) were synthesized by a standard solid state reaction route. Tetragonal Ruddlesden-Popper (R-P) solid solutions (Sr1-xCax)2TiO4 with space group I4/mmm were obtained in the composition range of x = 0~0.15, while Sr3Ti2O7 has been observed as secondary phase in x ≤ 0.10. In the present ceramics, both the dielectric constant ɛr and temperature coefficient of resonant frequency τf decreased at first and turned to increase again with increasing x, while the quality factor Qf decreased slightly at first and turned to decrease sharply after x = 0.1. The improved microwave dielectric properties with the best combination were obtained in (Sr1-xCax)2TiO4 ceramics at x = 0.075: ɛr = 39.3, Qf = 93 550 GHz, τf = 119 ppm/°C The obvious improvement was achieved in temperature coefficient of resonant frequency (from 140 to 119 ppm/°C) with Ca2+-substitution for Sr2+ in Sr2TiO4 ceramics due to the increased B-site bond valance. 相似文献
476.
Ayesha Kausar 《Polymer-Plastics Technology and Engineering》2019,58(9):934-947
This article highlights research endeavors on various aspects of polymer/modified chitosan nanocomposite counting their fabrication, features, application, and future prospects. Chitosan is biocompatible/biodegradable polymer having exclusive physical and chemical properties in modified forms. Chitosan possess enormous structural prospects through functionalization with carbon nanotube, graphene, nanoclay, and metal nanoparticle. Modified chitosan own optimal moisture absorption, heat stability, chemical and flame resistance. Incorporation of nano-functionalized chitosan in matrices generate innovative efficacies of nanocomposite in sensors, dye removal, membrane technology, packaging, antimicrobial, and biomedical materials. Polymer/modified chitosan nanocomposite reveal superior characteristics such as strength, heat stability, electrical conductivity, photo-luminescent, antimicrobial, and biomedical features. 相似文献
477.
In this paper, pineapple stem (PS) waste, an agricultural waste available in large quantity in Malaysia, was utilized as low-cost adsorbent to remove basic dye (methylene blue, MB) from aqueous solution by adsorption. Batch mode experiments were conducted at 30 degrees C to study the effects of initial concentration of methylene blue, contact time and pH on dye adsorption. Equilibrium adsorption isotherms and kinetic were investigated. The experimental data were analyzed by the Langmuir and Freundlich models and the isotherm data fitted well to the Langmuir isotherm with monolayer adsorption capacity of 119.05mg/g. The kinetic data obtained at different concentrations were analyzed using a pseudo-first-order and pseudo-second-order equation and intraparticle diffusion equation. The experimental data fitted very well the pseudo-second-order kinetic model. The PS was found to be very effective adsorbent for MB adsorption. 相似文献
478.
The purpose of this work is to obtain optimal preparation conditions for activated carbons prepared from rattan sawdust (RSAC) for removal of disperse dye from aqueous solution. The RSAC was prepared by chemical activation with phosphoric acid using response surface methodology (RSM). RSM based on a three-variable central composite design was used to determine the effect of activation temperature (400–600 °C), activation time (1–3 h) and H3PO4:precursor (wt%) impregnation ratio (3:1–6:1) on C.I. Disperse Orange 30 (DO30) percentage removal and activated carbon yield were investigated. Based on the central composite design, quadratic model was developed to correlate the preparation variables to the two responses. The most influential factor on each experimental design responses was identified from the analysis of variance (ANOVA). The optimum conditions for preparation of RSAC, which were based on response surface and contour plots, were found as follows: temperature of 470 °C, activation time of 2 h and 14 min and chemical impregnation ratio of 4.45. 相似文献
479.
In this study, advanced oxidation process utilizing Fenton's reagent was investigated for degradation of malachite green (MG). The effects of different reaction parameters such as the initial MG concentration, initial pH, the initial hydrogen peroxide concentration, the initial ferrous concentration and the reaction temperature on the oxidative degradation of MG have been investigated. The optimal reacting conditions were experimentally found to be pH 3.40, initial hydrogen peroxide concentration=0.50mM and initial ferrous concentration=0.10mM for initial MG concentration of 20mg/L at 30 degrees C. Under optimal conditions, 99.25% degradation efficiency of dye in aqueous solution was achieved after 60 min of reaction. 相似文献
480.
The adsorption characteristics of 2,4,6-trichlorophenol (TCP) on activated carbon prepared from oil palm empty fruit bunch (EFB) were evaluated. The effects of TCP initial concentration, agitation time, solution pH and temperature on TCP adsorption were investigated. TCP adsorption uptake was found to increase with increase in initial concentration, agitation time and solution temperature whereas adsorption of TCP was more favourable at acidic pH. The adsorption equilibrium data were best represented by the Freundlich and Redlich-Peterson isotherms. The adsorption kinetics was found to follow the pseudo-second-order kinetic model. The mechanism of the adsorption process was determined from the intraparticle diffusion model. Boyd plot revealed that the adsorption of TCP on the activated carbon was mainly governed by particle diffusion. Thermodynamic parameters such as standard enthalpy (DeltaH degrees ), standard entropy (DeltaS degrees ), standard free energy (DeltaG degrees ) and activation energy were determined. The regeneration efficiency of the spent activated carbon was high, with TCP desorption of 99.6%. 相似文献