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Mango fruit ( Mangifera indica L.) is highly perishable and must therefore be quickly stabilized. Drying appears to be one of the most promising stabilization solutions. The traditional mango drying process can be divided into two phases: the first, which is performed at ~80 °C for 10 to 12 h, sees water activity ( a) decline from 0.98 to 0.8. During the second phase, the drying temperature is reduced to 50 °C until a reaches ~0.6. These conditions are highly favorable to enzymatic and non-enzymatic reactions (1st and 2nd step, respectively). The focus of this work was therefore to highlight the effects resulting from the coupling of a and temperature on the development of these classes of reactions during the whole process. Several precursors (reducing sugars and amino acids) and intermediary products of the Maillard reaction were analyzed to estimate non-enzymatic reaction intensity when polyphenoloxidase (PPO) was associated with enzymatic browning. We were able to show that the highest production of 5-hydroxymethyl furfural (5-HMF) as a Maillard reaction marker occurs mainly for an a of 0.6. Kinetic analysis of Maillard reaction precursors and intermediate products in model mango system helped us identify asparagine and arginine as limiting precursors, and 5-HMF as a significant a-dependent product. The impact of the a on the thermal degradation of PPO proved to be radically different. After 8 h at 40 °C, the PPO was almost totally inhibited if this treatment is conducted on a sample at a 0.65, while residual activity was estimated to be 69.4 % for a sample at a 0.98. [ABSTRACT FROM AUTHOR]

Kitoza samples collected from producers in Madagascar were analyzed for their physicochemical and microbial properties. Lactic acid bacteria and coagulase‐negative staphylococci were the two codominant populations with average counts of 6–7 log cfu/g. Good hygienic practices were sometimes lacking but samples were not contaminated with Salmonella, Clostridium perfringens, and Bacillus cereus and only once with Listeria monocytogenes. Staphylococcus aureus was found occasionally with higher counts in salted/dried products than in salted/smoked products. Moisture, protein, fat, and salt contents varied considerably and were on average 41.5, 43.5, 14.3, and 3.3 g/100 g, respectively, and water activity was 0.893 on average. Smoked kitoza showed higher moisture content compared to dried kitoza. Most of the smoked kitoza had a water activity higher than 0.9 which is not in accordance with their storage at ambient temperatures. Benzo(a)pyrene content was above 2 µg/kg in 11 out of 30 smoked samples (17 ± 16.5 µg/kg on average). [ABSTRACT FROM AUTHOR]