We investigated the genetic factors controlling fruit components in coconut by performing QTL analyses for fruit component weights and ratios in a segregating progeny of a Rennell Island Tall genotype. The underlying linkage map of this population was already established in a previous study, as well as QTL analyses for fruit production, which were used to complement our results. The addition of 53 new markers (mainly SSRs) led to minor amendments in the map. A total of 52 putative QTLs were identified for the 11 traits under study. Thirty-four of them were grouped in six small clusters, which probably correspond to single pleiotropic genes. Some additional QTLs located apart from these clusters also had relatively large effects on the individual traits. The QTLs for fruit component weight, endosperm humidity and fruit production were found at different locations in the genome, suggesting that efficient marker-assisted selection for yield can be achieved by selecting QTLs for the individual components. The detected QTLs descend from a genotype belonging to the "Pacific" coconut group. Based on the known molecular and phenotypic differences between "Pacific" and "Indo-Atlantic" coconuts, we suggest that a large fraction of coconut genetic diversity is still to be investigated by studying populations derived from crosses between these groups.

Aims: To evaluate and compare some physico-chemical characteristics of powdered sugar from the inflorescences of three of the most widespread coconut cultivars in Côte d'Ivoire compared to sugar from cane sugar to diversifying coconut exploitation in Côte d'Ivoire. Experimental Design was Used: The sap was extracted from inflorescences of row 8 of PB113+, PB121+ hybrid and GOA cultivar. Three different treatments that varied time and temperature were set. The physico-chemical characterization concerned the sugar samples from each pair. Samples of white and brown sugar from sugar cane, sold commercially in Côte d'Ivoire, were used as controls.   Place and Duration of Studies: Marc Delorme Station for Coconut Research at the National Centre for Agricultural Research, Côte d'Ivoire between January 2017 and March 2018. Methodology: The sap from the freshly collected coconut tree inflorescences was directly transformed into granulated sugar by thermal spraying (Okoma et al, 2019), without preservatives. Three treatments varying the time/temperature pair were tested. Thus, the processing consisted of: T1: boil 1 liter of sap for 45 minutes at a temperature varying from 60-120°C. T2: boil 1 liter of sap for 40 minutes at a temperature varying from 60-140°C. T3: boil 1 liter of sap for 35 minutes at a temperature varying from 60-160°C. The physico-chemical characterization concerned the coconut sugar samples from each treatment and covered the dry matter content (DMS), moisture (HUM), ashes content (ASH), hydrogen potential (pH), titratable acidity content (TAT), total and reducing sugar contents, fat content and crude fibers. We considered the white and brown sugar from sugar cane sold in the sample as control samples. Results: All the physico-chemical characteristics of the crystalline coconut and sugar cane sugars analyzed generated significant differences (p<0.5) between them and the controls. Regardless of the treatment, the controls white and brown cane sugar provide statistically identical DMS, greater than 99.45 g/100 g respectively. These levels are higher than those provided by the sugar of coconut cultivars. In addition, white (0.27 to 0.29) and brown (0.42 to 0.50) cane sugar contains less water than all coconut cultivars (0.76 to 1.70). Regardless of the treatments applied, crystalline coconut sugar contains ashes contents (ASH) that range from 1.45 to 2.85 and are statistically higher than the proportions found in brown sugar cane sugar (0.11 to 0.28). White sugar cane sugar does not contain ashes. The pH of white sugar and brown sugar (6.09 and 6.44) is significantly higher than that of coconut sugar (4.82 and 6.19). The titratable acid content of coconut sugar ranged from 1.25 to 2.19 compared to 0.94 to 1.99 in cane sugar. Total sugar contents (TST) represent 81.15 to 87.54% of the dry matter in coconut cultivars. This is lower than the TSTs for white sugar (99.01 to 99.04%) and brown sugar (95.6 to 95.73%) sugar cane. Crystal sugar in coconut cultivars contains statistically fewer reducing sugars (6.75 to 7.89%) than white sugar cane sugar (8.11 to 8.12%). Its red counterpart, with 6.14%, contains smaller amounts of reducing sugars. Conclusion: Sugars are the main constituents of the dry matter of the coconut and cane sugar crystals studied. However, the different heat treatments applied to the sap of coconut inflorescences significantly affected all the physico-chemical parameters of each sugar. The physico-chemical characteristics have statistically differentiated coconut sugar from sugar cane sugar. However, for a better valorization of crystalline coconut sugar in Côte d'Ivoire, additional studies to determine its carbohydrate, mineral, vitamin and energy content should be considered.

Aims:To develop a method for transforming inflorescences sap of coconut into crystalline sugar, with a view to diversifying coconut exploitation in Côte d'Ivoire. Study Design: The sap was extracted from inflorescences of row 8 of PB113 hybrid and harvested 03 times a day (07h, 12h and 17h). Three processes for transforming sap into crystalline sugar have JEAI, 39(2): 1-9, 2019; Article no.JEAI.50035 2 been gradually tested, taking into account the quality of the sap, the temperature-treatment time combination and the physical constraints applied to the sap. Place and Duration of StudiesMethodology: Six coconuts was selected from those that showed no evidence of a history of disease or pest attack. Then, in their leaf corona, the unopened inflorescences, rank 8, were used for sap extraction [12]. On each coconut tree, the sap was collected in a plastic container previously sanitized with water heated to 100°C in a boiling bath and was collected 03 times a day (07h, 12h and 17h). The collected samples were placed in an isothermal cooler before being sent to the laboratory for processing. The transformation of sap into derived products was carried out by thermal spraying of the raw material. The experiments were performed on an electric hot plate (TRIOMPH) equipped with a temperature and time regulator. Heating the sap also required a frying pan and stainless-steel spatulas. A pH meter, a 0.01 electronic precision balance (METTLER BD 202, made in USA) and a refractometer were also used to measure physico-chemical parameters of the sap before and during its transformation. Three (3) processes were tested in this study for the transformation of inflorescences sap into coconut sugar. In each process, variable time-temperature heating combinations were used. Results: Both first one's processes tested did not produce sugar crystals. Their deficiencies were improved in the 3rd process which resulted in the clear crystallization of the sap. With this process, a first vaporization of the sap was carried out with gradually increasing temperatures up to 140°C for 30 min giving a fairly firm coconut syrup. The syrup was sprayed for a second time at 60°C for 30 minutes to obtain a massecuite, which was then destemmed, crumbled and dried at ambient temperature to provide crystalline coconut sugar. This sugar comes in the form of crystals of irregular grain size with a red coloring, similar to brown cane sugar. The results reveal that the production of 1 kg of crystalline coconut sugar requires the treatment of 6.25 L of coconut inflorescences sap. Conclusion: The extension of the method of production of crystalline coconut sugar must be encouraged and represents an important support for the development of coconut sap in Côte d'Ivoire. However, further studies must be carried out to determine the biochemical characteristics of the coconut sugar produced. Original Research Article

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In order to do a best stipulation on her consumption, it is necessary to know if a food provoke faintly, fairly or highly the glyceamia. The aim of this work was to evaluate the glycemic index of coconut water sugar from three coconuts varieties. So, with a cohort of 15 people, a capillary blood was collect after sugar ingestion and the glycaemia read directly on a glucometer. The result showed that the brown and white sugar from coconut sugar can be classified as low glycemic index food. Also, the glycemic indexes of white coconut water sugar are 2 to 3 more lower than that the brown sugar. The glycemic indexes of sugars vary according to the variety of coconut used. The sugars of the coconut palm (MYD) are more hyperglycemic than those of the hybrid (PB121 + ) which is more hyperglycemic than the sugars of the coconut palm (WAT). Thus, with a controlled consumption, the coconut water sugars could be the sugars that are best for the health of the healthy and diabetic populations because it raises slightly the postprandial glucose.