Whole grain flour is gaining an increase in demand for its nutritive and health promotion values in different food products for human consumption worldwide. Whole flour from wheat grain varieties (Gihundo, Kibatsi, Nyaruka and Reberaho), spent coffee grounds (SCG), juices of lemon fruit (L) and rosemary leaves (R), and dough fermentation were assessed for their impact on the texture profile, colour and sensory attributes of bread. Wheat grains (sampled from the stores of Rwanda Agriculture and Animal Resources Development Board, Kinigi, Rwanda) were conditioned to 15.5% moisture content and were wholly milled. The mixture of 200 g whole wheat flour, 4% spent coffee grounds, 1% juice of lemon fruit and 1% juice of rosemary leaves were fermented by using 2% instant dry yeast at 34 °C, 60% relative humidity (RH) for 60 min and at 39 °C, 85% RH for 120 min, separately. The dough was baked at 180 °C for 20 min. Data were subjected to one-way analysis of variance using SAS System. Treatment means were separated using Tukey’s test and the least significant difference was accepted at p ≤ 0.05. The control bread was made for 60 min of fermentation without incorporation of SCG and LR. The control bread was harder than the bread containing SCG and SCG+LR with the same time of fermentation. The long fermentation and the inclusion of SCG and SCG+LR in doughs, caused the supplemented bread to have lower L*, a* and b* values than control bread. Low L*, a* and b* values indicate minimum darkness, redness and yellowness of bread. Aroma, taste and appearance of SCG+LR bread from doughs fermented for 120 min were the most liked. Whole wheat bread obtained satisfied consumers’ preferences. Therefore, the application of spent coffee grounds, juices of lemon fruit and rosemary leaves in bread making represents a good opportunity at low cost.

The present investigation is to evaluate ethanol production from coffee pulp and mucilage as coffee by-products, which was used as substrate. Material and methods: Wort extracted from pulp and mucilage was fermented; molasses sugar was used to optimize in terms of concentration and increase reducing sugars for fermentation process; acid hydrolysis was performed to breakdown complex polysaccharides from pulp and mucilage into simple monomers. Dry yeasts used as Saccharomyces cerevisiae were rehydrated and supplemented by nutrients rich in nitrogen, magnesium and carbon before being pitching in the wort; appropriate materials for hermetic process of fermentation were used and regular controlled. Results and discussion: The variation of reducing sugars in a substance shows the evolution of fermentation process. During this fermentation process, it has been realized that the sugar content has decreased, by comparing with the initial level and final, before and after fermentation, is directly related to the fermentation efficiency. The end of process was realised when the density has decreased below 6%. The obtain results after fermentation, was also continued by conducting distillation; the 6.5l as amount of wort produced 2.3l of ethanol with 45% absolutely volume, equivalent to 35.5% of wort volume. Since pH of wort was optimised to 4-5 for fermentation, the results show that ethanol production can be produced and viable using coffee pulp and mucilage as by-products and reduce the contamination of them to the environment. For this case study, by optimizing alcohol concentration, the pH, and temperature have been kept constant for all samples. Conclusion: Processing of the coffee mucilage and pulp as by-products to ethanol can increase raw material resources suitable for ethanol production for various purposes in Rwanda and this confirm that ethanol production from mucilage and pulp of coffee is possible as results show the potential to use them instead of considering them as waste.

<p>The present study aimed to evaluate the effect of the wheat varieties newly introduced in Rwanda on the physicochemical characteristics of their whole wheat grains in order to know their potentials for processing. Gihundo wheat grain variety had the highest values for extraction yield (99.20 %), contents of ash (1.47 %) and total dietary fiber (15.97 %), water absorption capacity (89.00 %), dough development time (7.62 min) and brightness (84.67 %). For the same physicochemical characteristics, whole flour from Nyaruka wheat variety showed the lowest values for extraction yield (96.20%), water absorption capacity (80.00 %), dough development time (6.33 min) and brightness (80.33), while whole flour from Reberaho wheat variety exhibited the lowest values for the contents of ash (0.98 %) and total dietary fiber (12.44 %). The protein content ranged between 10.00 % and 10.85 % for whole flours from all wheat varieties. The results showed that whole flour from Gihundo wheat grain variety exhibited high values for most of the physicochemical characteristics determined in comparison to the other three varieties. It is important to select grains or flour from these wheat varieties newly introduced in Rwanda based on the individual cultivar because their derivative products could have a more desired quality.</p>