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Caffeine biosynthesis in Coffea evolved independently through tandem gene duplication and subsequent neofunctionalization of ancestral N-methyltransferases (NMTs). The bulk of our understanding of this process in Coffea is centered on two species: C. arabica and C. canephora. To gain a wider perspective of caffeine biosynthesis in Coffea, this study focused on the less popular but commercially available C. liberica var. liberica, locally known as "kapeng barako." This study aimed to determine the genomic and coding sequences of the three NMTs -- mainly, xanthosine methyltransferase (XMT), 7-methylxanthine-N-methyltransferase (MXMT), and dimethylxanthine methyltransferase (DXMT) -- through Sanger sequencing. Relative expression levels of these NMTs in the leaves, flower bud, green fruit, and red fruit stages were also determined through polymerase chain reaction amplification of synthesized cDNA and then gel electrophoresis. Results reveal that the genetic sequences of NMTs of C. liberica were similar to the C. eugenioides-derived NMTs of C. arabica. Results also indicate that there is a possibility that more than one NMT gene for each NMT cluster (XMT, MXMT, DXMT) exists. This study has also identified genomic sequences and transcripts, whose sequences were in between the XMT and MXMT gene clusters. The function of these novel sequences is yet to be determined. NMT expression levels in C. liberica were similar to those observed in C. arabica and C. canephora, wherein expression peaks at the green fruit stage and then diminishes, as the fruit ripens fully. Although the NMTs of C. liberica have a lot of similarities with C. arabica and C. canephora, discovering the function and role in caffeine biosynthesis of these novel genomic sequences and transcripts will help us further understand the evolution of caffeine biosynthesis in Coffea. [ABSTRACT FROM AUTHOR]

The Philippines is one of only a few countries where Coffea liberica is commercially produced. Two infra-species, C. liberica liberica (also locally known as 'liberica') and C. liberica var dewevrei (also known as 'excelsa') comprise 1.1% and 5.7% of the national coffee production, respectively. These rare varieties are produced widely in the provinces of Batangas and Cavite mainly because of historical affinity, a local market, and more recently the renewed interest from importers. Aside from its unique flavor profile, renewed interest comes from the potential of the larger beans and deeper root systems of the species to thrive on a warming planet. In this paper, we present work that has been performed in evaluating bean morphology, chlorogenic acid, caffeine content and genetic variability of C. liberica varieties from different areas of the country. The initial efforts to predict areas for increased production were based on a maximum entropy model. Combining these data provides insights into development areas for increased production in the Philippines. [ABSTRACT FROM AUTHOR]

Coffea liberica originally found near Monrovia in Liberia is the third commercially exploited coffee species known for its larger cherries, compared with those of Coffea arabica or Coffea canephora; it contributes less than one per cent of the marketed coffee. The latter reflects in part the beverage quality being inferior to that of Arabica and in part the agronomical performance not satisfying when compared with those of Robusta. However, this species remains still attracting for some genetical characteristic like certain pest resistance genes in breeding programs as the resistance to coffee leaf rust conferred by the SH3 locus. Currently, all Liberica taxa were grouped in one species, C. liberica W. Bull ex Hiern that included two varieties, C. liberica var. liberica, C. liberica var. dewevrei (De Wild. and T. Durand) Le Brun, and a form C. liberica f. bwambensis Bridson. The taxonomic differences between the two varieties still raise doubts that leave the question 'species or variety?' still open. For this reason, the search of possible traits or molecular markers able to discriminate and shed light on these doubts has never stopped. In this paper we focus our attention on two characteristics not yet investigated in detail: silverskin tissue and seed diterpenes. For the first time, an in-depth microscopic study of silverskin morphology was used to discriminate liberica from dewevrei coupled with the diterpenes characterization, the major components of the unsaponifiable fraction of seed lipids, already known as molecular markers and efficiently used for coffee species authentication purposes. [ABSTRACT FROM AUTHOR]

Coffee constitutes a plant product high in economic value. Extremely abundant throughout Indonesia, different varieties can be found in each region. Coffee leaves represent a by-product of coffee production which are disposed of without being subjected to further processing. One advantage of coffee leaf waste is that it can be made into coffee leaf tea, to prevent various diseases. The caffeine and tannin content can be optimized by temperature and brewing time. Research on coffee leaf tea remains limited, with little study of Liberica coffee leaf tea. This investigation was to determine the optimal brewing time and temperature of Robusta (Coffea canephora) and Liberica (Coffea liberica) coffee leaf tea. This research used the Response Surface Methodology (RSM) method with Central Composite Design (CCD). Data analysis using RSM method was conducted incorporating two factors. The first factor was the brewing temperature with a minimum value of 91 °C and a maximum value of 99 °C. The second factor was brewing time with minimum and maximum values of three and seven minutes respectively. Identifying the optimal treatment was based on two factors, caffeine and tannin content. Optimized processes were applied to conduct organoleptic tests on 110 untrained panelists using the Rate-All-That-Apply (RATA) method to highlight the majority attributes experienced by the panelists. The optimal brewing temperature and duration for robusta coffee leaf tea were 93.43 °C and 4.80 minutes which produced caffeine and tannin levels of 74.90 mg.100mL-1 and 293.01 μg.g-1 respectively. In contrast, in the case of Liberica coffee leaf tea, the optimal brewing conditions comprised a temperature of 91.65 °C and duration of 4.84 minutes which produced caffeine and tannin levels of 72.52 mg.100mL-1 and 415.87 μg.g-1. Results of sensory analysis showed that the majority produced five significant characteristics, namely: sweet flavor, fire flavor, sweet taste, bitter taste and astringent mouthfeel. [ABSTRACT FROM AUTHOR]

Coffee constitutes a plant product high in economic value. Extremely abundant throughout Indonesia, different varieties can be found in each region. Coffee leaves represent a by-product of coffee production which are disposed of without being subjected to further processing. One advantage of coffee leaf waste is that it can be made into coffee leaf tea, to prevent various diseases. The caffeine and tannin content can be optimized by temperature and brewing time. Research on coffee leaf tea remains limited, with little study of Liberica coffee leaf tea. This investigation was to determine the optimal brewing time and temperature of Robusta (Coffea canephora) and Liberica (Coffea liberica) coffee leaf tea. This research used the Response Surface Methodology (RSM) method with Central Composite Design (CCD). Data analysis using RSM method was conducted incorporating two factors. The first factor was the brewing temperature with a minimum value of 91 °C and a maximum value of 99 °C. The second factor was brewing time with minimum and maximum values of three and seven minutes respectively. Identifying the optimal treatment was based on two factors, caffeine and tannin content. Optimized processes were applied to conduct organoleptic tests on 110 untrained panelists using the Rate-All-That-Apply (RATA) method to highlight the majority attributes experienced by the panelists. The optimal brewing temperature and duration for robusta coffee leaf tea were 93.43 °C and 4.80 minutes which produced caffeine and tannin levels of 74.90 mg.100mL-1 and 293.01 µg.g-1 respectively. In contrast, in the case of Liberica coffee leaf tea, the optimal brewing conditions comprised a temperature of 91.65 °C and duration of 4.84 minutes which produced caffeine and tannin levels of 72.52 mg.100mL-1 and 415.87 µg.g-1. Results of sensory analysis showed that the majority produced five significant characteristics, namely: sweet flavor, fire flavor, sweet taste, bitter taste and astringent mouthfeel. [ABSTRACT FROM AUTHOR]

Liberica coffee is the most important coffee species grown in Malaysia. However, there is little or no research at all conducted on coffee berries and green coffee beans since the plant itself is a low income crop in Malaysia. Therefore, research on Malaysian Liberica coffee can help to increase the knowledge of coffee fanners and coffee manufacturers in the processing and handling of the coffee. Physical properties of Liberica coffee berries and beans were investigated the current study. The properties investigated include the size, mass, density, coefficient of friction, angle of repose, fracture force and colour. In comparison to Arabica and Robusta coffee, Liberica coffee has the biggest size, mass, true density and fracture force values but were lower in bulk density in both berries and beans. The Liberica berries and beans were found to be orange-ish and yellowish colour respectively. Angle of repose was low and approximately similar in berries and beans while jute fibre gave the highest friction to both Liberica berries and beans. [ABSTRACT FROM AUTHOR]

Green coffee beans are stored for a certain period and under certain conditions until they are finally utilized. The storage period may depend on customer demand while the storage conditions depend on where the coffee beans are stored. Thus, this research emphasizes the physico-chemical changes that occur in Liberica coffee beans during storage under the Malaysian climate (average temperature and relative humidity of 29.33°C and 71.75% respectively). The changes in the physico-chemical (coffee size, mass, densities, colour, proximate analysis, sucrose, chlorogenic acid content) and microbiological (yeast and mould count) properties were evaluated during eight months of storage. After the storage, the physical properties of the coffee changed as the coffee beans expanded in size, reduced in mass and density and became brighter in colour. Changes in the chemical properties were also detected where the moisture decreased and the ash content increased. In addition, the sucrose level was found to decrease with a corresponding increase in chlorogenic acid. During storage, the counts of yeast and mould were reduced. Model equations describing the changes in the properties were developed. The overall conclusion was that the coffee beans reduced in quality during storage. [ABSTRACT FROM AUTHOR]