Extracts fromHibiscus sabdariffaL. (roselle) have been used traditionally as a food, in herbal medicine, in hot and cold beverages, as flavouring or coloring agent in the food industry. In vitro and in vivo studies and trials provide evidence, but roselle is poorly characterised phytochemically due to the extraction processes. The optimization of the extraction of phenolic compounds and their antioxidant activities is still a hot topic. In this study, the effect of solute/solvent ratio (33, 40 and 50 mg/mL), extraction temperature (40, 50 and 60 °C) and extraction time (30, 60 and 90 min) was evaluated through the content of phenolic compounds and antioxidant activity. A response surface methodology through a Box–Behnken design was applied and model fit, regression equations, analysis of variance and 3D response curve were developed. The results showed that TPC, TFC, DPPH and FRAP were significantly influenced by temperature, extraction time and solvent/solute ratio. Thus, TPC, TFC, DPPH and FRAP varied from 5.25 to 10.58 g GAE/100 g DW; 0.28 to 0.81 g QE/100 g DW; 0.24 to 0.70 mg/mL; 2.4 to 6.55 g AAE/100 g DW respectively. The optimal experimental condition (41.81 mg/mL; 52.35 °C and 57.77 min) showed a significant positive effect compared to conventional methods. The experimental values at this extraction condition show that this optimization model is technologically, financially and energetically viable as it requires a reasonable concentration, time and temperature.

The cashew plant is an allogamous plant that produces two types of fruits: the nut and the cashew apple. The present study was conducted to perform a comparison of proximate and phytonutrient compositions of cashew (Anacardium occidentale L.) nuts and apples from different geographical areas of Burkina Faso. For this purpose, 60 samples of apples and kernels were collected from the three main cashew cultivation areas. The nutritional potential of cashew nuts and apples produced was evaluated to enhance their food processing. Protein, carbohydrates, lipids, dietary fibers, ascorbic acid, tannins, anthocyanins, chlorophyll, lycopene, and β‐carotene contents were assessed. The results revealed high contents of lipids (50.42 ± 2.3 g/100 gDW), proteins (22.32 + −1.8 g/100 gDW), and starch (12.05 ± 1.27 g/100 g DW) in almonds. Apples, on the other hand, are rich in lipids, ascorbic acid (387.45 ± 17.4 mg/100 g), soluble sugars (387.45 ± 17.4 mg/100 g,), and pigments (lycopene, anthocyanin, β‐carotene, and chlorophyll). In summary, almonds may be suitable as a source of lipids and related products. Apples can be used as natural antioxidants and produce juices. All of these data are important clues for cashew by‐product processing. These results obtained provide a scientific basis for their food and economical valorization of cashew fruits.

(1) Background: Sorghum (Sorghum bicolor (L.) Moench) is a staple food cereal for most of the rural populations in sub-Saharan Africa. In Burkina Faso, a great diversity of sorghum cultivar is cultivated, but its nutritional potential still needs to be assessed. This study aims to characterize the physicochemical and nutritional profile of grains from 15 sorghum cultivars grown in Burkina Faso in order to identify the best ones for selection and breeding programs. (2) Methods: The physicochemical, nutritional, and antioxidant-activity characterizations of the grains were performed according to standard methods. (3) Results: The study shows significant differences between cultivars according to the physicochemical traits of the grains, such as 1000-grain weight, moisture, and germination rate. For nutritional parameters, the best contents of carbohydrates (79.36%), proteins (9.21%), and fats (4.40%) were recorded with cultivars V12, V8, and V11, respectively. The heavy grains are flouriest with high contents of carbohydrates with high ABTS antiradical activity. However, these grains have low contents of proteins and flavonoids. Those with high ash contents are the richest in amylose and phenolic compounds. Principal component analysis based on physicochemical and nutritional characteristics of sorghum grains identified four groups of varieties with specific characteristics. Group 1 (G1), which includes cultivars V1, V12, V13, V14, and V15, is characterized by a high weight of 1000 grains and mealy cultivars with relatively high total carbohydrate content and ABTS^.+ antiradical activity. Group 2 (G2) includes cultivars V7, V9, and V11 and is characterized by cultivars with low 1000-grain weight, less floury but good germination rate, high protein, flavonoids, and relatively high antioxidant activity. Group 3 (G3) includes cultivars V3, V4, and V8 with relatively high ash, amylose, and polyphenol contents, while group 4 (G4), which includes cultivars V2 and V6, has high antioxidant activity and high fatty acid content. Conclusions: The study recorded a variation of physicochemical and nutritional characteristics of sorghum grain according to cultivars. The cultivars were divided into four groups. Among them, the group 1 cultivars have the best nutritional traits and could therefore be used in breeding and selection programs to improve the nutritional potential of sorghum.

The edible oil needs of African countries are met by imported or locally produced ones. Therefore, consumers are generally confronted with a choice of edible oils of poorly controlled quality. However, quality control of edible oils for local consumption is of high necessity. This study aimed to assess the quality of edible oils sold and consumed in some cities in Burkina Faso. Oil samples collected in the cities of Dédougou, Koudougou, and Nouna were used for several analyses. Oil samples from palm, refined and unrefined cottonseed, and groundnut were collected. Standard methods were used to assess the physicochemical quality parameters of the oils, including the peroxide value, water and volatile matter content, acid value, traces of soap, and mineral oil contents. The parameters varied significantly depending on the oil type, but not by the locality of origin. The peroxide indices had varied from 3.24 to 39.99 mEq O₂/kg oil. The acid indices varied from 0.22 mg KOH/g to 1.24 mg KOH/g. The water and volatile matter contents ranged from 0.04% to 0.88%. The test for traces of soap gave values ranging from 0 to 76 ppm. For the mineral oil test, four samples of cottonseed oil collected in Dedougou gave positive results. Compared to international reference standards, in particular the Codex Alimentarius standard, it may constitute a health risk for consumers. The poor storage, distribution, and marketing conditions of the oils could explain their poor quality. In order to provide consumers with quality oils, regular controls must be undertaken in the places where the oils are stored and/or marketed.

Cashew tree has two parts of food industry and nutrition interest, i.e the nut and the juicy apple. This study aimed to carry out a phytochemical characterization, determine the antioxidant properties and evaluate the influence of temperature on the phytonutrient composition of cashew fruits. The contents of ascorbic acids, phytates, and tannins, of various pigments were determined. Antioxidant activities were determined by four methods using standard methods. The apples presented the best antioxidant activities for FRAP, SOD, and LPO 98.54 ± 5.48, 834.12 ± 13.47, and 84.9 ± 4.15, respectively; while walnuts showed the best antioxidant activities for free radical scavenging which was 26.14 ± 3.21. Tannin, phytate, and anthocyanin contents decreased by more than 50% when increasing temperatures between 50 and 100°C. Ascorbic acid tends to disappear completely in fruit at temperatures of 100°C. Extractable lycopene increased by about 25% with increasing temperature. β-carotene was found to be insensitive to temperature increase. These results provide valuable information that can help in the control of cashew fruit processing in the food industry. They also provide important information on the nutraceutical potential of cashew fruit.