Aims: To investigate the dough rheological properties as well as physical, nutritional, antioxidant and sensory properties of biscuits supplemented   with dried microwave-blanched orange, apple and pomegranate peels at various levels (0-10%, wheat flour substitution). Methodology: Water absorption capacity and pasting properties of wheat flour blended with   fruit   peels   were   assessed   using   farinograph   and   micro   viscoamylograph. Physico-chemical properties as well as antioxidant activities were measured using standard methods. The sensory analysis was performed by trained panelists. Results: Water absorption capacity of the dough increased significantly with increasing levels of orange and apple peels while it decreased with pomegranate peels. However, peak,  hot  paste,  cold  paste  and  breakdown  viscosities  of  the  dough  significantly decreased with increasing proportions of apple and orange peels while they increased with pomegranate peels. The breaking force and weight of the biscuits supplemented with pomegranate peels were the lowest.  Supplementation of biscuits with fruit peelings enhanced the ash and fibre content of the biscuits but had no significant effect on their antioxidant activities except for biscuits containing 10% apple peels which had higher antioxidant activity compared to biscuit controls. Biscuits supplemented with 5% of fruit peels were the most appreciated in terms of surface character, crumb colour and texture. Conclusion:  This study showed that dried microwave-blanched apple peels can be incorporated into biscuits to enhance both their nutritional and antioxidant properties.

Response surface methodology was used to optimize the fermentation conditions for the total phenolics content and antioxidant activity of black tea (Camellia sinensis). Fresh tea leaves were fermented following a rotatable central composite design of eleven experiments replicated thrice. The minimum and maximum fermentation time and temperature were respectively of 1 - 3 h and 30 - 40 °C. The results demonstrated that fermentation time and temperature significantly affect the total phenolics content and antioxidant activity of black tea. The optimum fermentation conditions for the present study were at 36 °C for 35 min which the values for total phenolics content and total antioxidant activity were 38.99 g GAE/100 g dw and 19.74 mg VitC Eq/100 g dw, respectively. Antioxidant activity was strongly correlated with total phenolics content of black tea.

Palm wine is the commonest name of the beverage obtained from fermented palm sap, the exudate from tapped unopened spathe of oil palm tree (Elaeis guineensis). This refreshing wine of West and Central Africa is very sweet but within 24 hours the concentration of sucrose falls to less than 50% the initial amounts due to a rapid sugar fermentation by microorganisms. In Cameroon, Central Africa, traditional attempts to preserve palm wine imply the introduction of natural preservatives mostly barks and leaves from edible or medicinal plants. The leaves of Cymbopogon citratus, Pimenta racemosa, Vernonia amygdalina, Ocimum basilicum and the barks and the leaves of Garcinia lucida and of Adansonia digitata commonly used in palm wine preservation were analyzed for their chemical composition. The results showed that lipid, protein, ash, crude fiber, total sugars and vitamin C contents were respectively from 15.70 ± 1.13 to 23.57 ± 1.80%, from 8.38 ± 0.38 to 43.81 ± 3.69%, from 1.14 ± 0.17 to 10.06 ± 0.39%, from 11.74 ± 1.11 to 48.42 ± 0.55%, and from 1.49 ± 0.02 to 22.56 ± 0.59% and from 55.76 ± 3.15 to 175.71 ± 2.09 μg /100 g dw. The phyto-chemicals levels were respectively from 1.37 ± 0.22 to 3.61 ± 0.6 % for total alkaloids, 2.66 ± 0.12 to 4.80 ± 0.24 % for total phenolics and 0.57 ± 0.09 to 1.88 ± 0.09 mg /100 g dw for total saponins. Concerning anti-nutrients, the oxalates levels were higher than the threshold value (250 mg/100 g) reported as safety limit. Despise the proven antimicrobial benefits of alkaloids, saponins and phenolics found in those leaves and barks, caution shall be paid during their use due to their high oxalates levels.

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