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In West Africa, household energy transition has so far mainly been synonymous with the conversion from woodfuel to LPG. This paper analyses the failure of 30 years of household energy transition policies in Mali by combining two major frameworks: Multi-Level Perspective (MLP) and Social Practice Theory (SPT). Based on empirical field studies undertaken in Bamako since 1985 and on literature review, two historical narratives are presented, one focusing on the dynamics of the dominant woodfuel regime and the other on changes in cooking practices. The MLP analysis showed that all elements seemed aligned for destabilization of the dominant regime, yet the woodfuel regime has resisted and is maintained. The SPT analysis showed that the stability of cooking, eating and fuel purchasing practices did not converge towards and even opposed the transition to LPG. This paper shows that the MLP and SPT frameworks offer complementary perspectives for understanding transitions in developing countries. It concludes that the definition and implementation of energy policies need to integrate an analysis of daily practices and should consider that energy transition is not synonymous with the replacement of one fuel by another, but with new opportunities to diversify ways of cooking.

The endogenous alpha-galactosidase activity of cowpea seeds was characterized and modelled assuming Michaelian behavior. The aim is to use the resulting knowledge to optimize alpha-galactoside degradation during the soaking-cooking process. In this study, the alpha-galactosidase enzyme from Wankoun cowpea was extracted and its enzymatic activity was analyzed as a function of temperature, pH and the presence of some inhibitors. Enzymatic activity was optimal around 35 °C and a pH of 5.8. Activation and inactivation energy was evaluated at 50 ± 3 and 103 ± 9 kJ.mol−1, respectively. The strongest inhibitor was galactose with an inhibition constant KI of 0.28 ± 0.03 mM. Incubation of the enzyme extract with alpha-galactosides revealed a 10-h lag phase in the early stages that could be due to low pH, the action of inhibitors including galactose and the biosynthesis of alpha-galactosides. After the lag phase, the degradation of each alpha-galactoside occurred without the appearance of any intermediary product. The degradation of alpha-galactosides was observed with a Km of 1.7 ± 0.3 mM for raffinose; 3.6 ± 0.6 mM for stachyose and 15.9 ± 0.1 mM for verbascose. A long soaking step around 35 °C is suggested to maximize the alpha-galactosides enzymatic degradation.

Ablo is a rice or maize-based steam-cooked bread-like product, very popular in Benin, Togo and Ghana. This study optimized the processing steps of rice ablo using response surface methodology. The effect of precooking (proportions of flour and water, duration), kneading (wheat level, duration), fermentation (yeast level, temperature, duration) conditions to dough (gelatinization level, fluidity, proofing) and ablo (ethanol content, pH, density, cooking expansion, firmness, alveolar structure) properties were studied. It was demonstrated that ablo texture can be controlled by the fluidity of the fermented dough. Fluid fermented dough (at least 0.5 cm/s) expands adequately during steam-cooking and results in a less dense ablo in line with commonly consumed ablo. The optimal dough fluidity comes from a low gelatinization level of the precooked dough (less than 20%) and an intense fermentation (high yeast dose and long fermentation). Surprisingly, dough proofing appears to have no effect on final ablo expansion.

International audience; Low pungency, high aromatic potential and red color, give to Piper borbonense its originality when compared to Piper nigrum. Effects of blanching, sweating and drying on these characteristics were assessed. The three operations had no impact on the concentration of piperine and essential oil but affected the composition of essential oil slightly and considerably affected the color of the pepper. The ''wet process " , including blanching, sweating and drying, had the largest impact on the composition of aroma, increasing para-cymene content by 89% and reducing safrole content by 33% in dried pepper compared to fresh. Blanching increased the drying rate thus reducing drying time. Drying had a major impact on color, which changed from red to brown. The biggest differences observed led to reductions of 2.2, 7.9 and 8.4 units in L ⁄ ,a ⁄ and b ⁄ values, when chromatic values measured in fresh pepper were compared to those of dried pepper.

Over the 65–100 °C range and at a water content of 1.6 kg kg−1 db, a comparison was conducted between plantain paste (dispersion made of flour and water) and pulp pieces after cooking to evaluate their respective degree of starch gelatinization (α) and in vitro digestibility. Below 76 °C and at 100 °C, the gelatinization behaviour of starch into pulp pieces and paste was similar, whereas at 85 °C a significant mean relative difference was observed in between. For α in the 0–1 range, pieces of plantain pulp exhibited a lower rapidly digestible starch fraction (30%) and a higher resistant starch fraction (33%) than the flour paste, suggesting some structural effects. Both Weibull and exponential models showed a good fit for α over temperature range and starch digestibility fractions over α. Although no explicit relationship was established between the intact pulp structure and grinded flour state of plantain, the evaluation of the degree of starch gelatinization and digestibility of a plantain flour paste, could be used to predict the gelatinization and digestibility behaviour of plantain starch in entire pieces of pulp.

Bananas and plantains (Musa spp.) constitute an important component of the diet in Africa. Substantial levels of provitaminAcarotenoids (pVACs) in Musa fruit have been reported, but the bioaccessibility of these pVACs remains unknown. In this study, we used an in vitro digestion model to assess the bioaccessibility (i.e. the transfer into micelles) of pVACs from boiled bananas and derived dishes using the Eastern Democratic Republic of Congo as a study context. In particular, the effect of different food ingredients added to boiled bananas on pVAC’s bioaccessibility was studied. The bioaccessibility of all-trans β-carotene ranged from 10% to 32%, depending on the food recipes, and was modified, particularly when pVACs-rich ingredients (palm oil/amaranth) were added. Efficiency of micellarization of all-trans β-carotene was similar to that of all-trans α-carotene and depended on the cultivar (Musilongo, plantain type, 16%; Vulambya, East African cooking type, 28%), while that of the 13-cis isomer was higher (21–33.5%). Taking into account bioaccessibility, the estimated vitamin A activity was significantly different across the different Musa-based dishes tested. Results are discussed in terms of recommendations to help reduce vitamin A deficiency in Musa-dependent African communities. Highlights • Bioaccessibility of carotenoids from plantain bananas has never been investigated. • Carotenoidsbioaccessibility is necessary to establish retinol activity equivalent. • Musa-dishes can contribute to the daily vitamin A requirement of target population. • The promotion/consumption of Musa-food helps to reduce vitamin A deficiency in Africa.

This paper describes the multidimensional features of the texture of cooked rice (in particular the visual aspect and mechanical attributes) determined by sensorial analysis and links these attributes with a wide range of physicochemical characteristics of raw grain (in particular certain cell wall components). Textural classes of cooked rice did not fit classical grain ranking, which is primarily based on shape. For the classification of cultivars, it would be preferable to use chemical characteristics of raw kernels such as amylose content and Tgel (for prediction of firmness), but also protein (adhesiveness and stickiness) and arabinoxylan contents (deformation), which determine the textural properties of cooked rice. Leached amylose has been measured, and the particular role of soluble amylose on the surface behaviour (stickiness and adhesiveness) of the cooked grain is discussed.

There has been recent interest in developing hot smoking kilns avoiding benzo(a)pyrene deposition on meat. An experimental kiln limiting this deposition phenomenon has been designed, built and tested. This kiln is used to dry, smoke and cook pork meat in order to obtain boucane , a traditional smoked product from La Reunion Island. Smoking is performed by using cooled pyrolysis smoke, while heating is obtained by means of radiant metal plates heated by combustion smoke. The dimensioning of the drying–cooking chamber has been performed by developing and solving a dynamic model that takes into account the heat and mass transfer phenomena on a local scale. This paper is mainly devoted to the presentation of this model and to the comparison of the first experimental results—concerning temperature variations in the chamber, and the product temperature and mass loss—to numerical simulation results. Some results obtained from dynamic simulations are discussed. The relative influences of the system dimensions, of the radiative transfers and of the drying phenomena on the performances of the system are discussed.

An assessment of various limitations in the traditional preparation of boucan e pork indicated that the process and the end-product quality could be enhanced by certain innovations. The overall aim is to improve the quality of the end product while retaining the uniqueness and specific traits of traditional boucan e and also to assess the innovation potential with respect to processing a range of pork-based products. For that reason, a novel technique involving immersion in a complex solution is proposed as an alternative to traditional processing. A predictive model was thus developed, combining a kinetic approach with surface response methodology. Mass transfers and impact on final product quality were discussed. With this innovation, the meat product can be salted, dried, cooked and smoked in a single step.

ABSTRACI’ The influence ofpasta c.ooking time on starch digestion and plasma glucose and insulin responses was studied in 12 healthy subjects. During 3 consecutive days, one of three pasta test meals (50 g starch) cooked for 1 1, 16.5, and 22 mm was served to each volunteer in a random order. Hydrogen and methane breath excretion was measured after pasta ingestion; plasma responses were compared with those of an equivalent oral glucose-tolerance test. No significant differences were found between cooking times and plasma indices, orocecal transit time, or incremental hydrogen excretion (� peak hydrogen). With one exception, pasta meals that were completely absorbed were ingested by methane producers. Postprandial � peak hydrogen was significantly lower in methane than in nonmethane producers (p < 0.02). These results point to a lack of influence ofcooking time on nutritional characteristics of pasta and suggest that starch malabsorption determined by breathhydrogen-test criteria may be underestimated in methane producers. Am J C/inNuir 1990;5l:421-7.