Lack of nutrients in cooking water, high energetic costs, high water consumption and recycling are some drawbacks of vegetable blanching. Those disadvantages could be bypassed using microwave blanching. Three blanching methods (microwave, boiling water and steaming) were compared in this study in order to determine their effects on some functional properties of broccoli. In addition, the thermal damage on broccoli colour was evaluated. The effectiveness of each blanching process was performed measuring the lost of peroxidase activity, that results more rapidly in microwaves and steam treatments (50 and 60 s respectively) than in boiling water treatment (120 s). The colour indexes did not allow to discriminate a significant difference among treatments. The increase of treatment time caused a vitamin C decrease in samples blanched by boiling water and steam; this trend was not observed in microwaved samples. The phenols content did not significantly vary depending both on type and on time of treatment.

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The stabilisation of preserves through the lowering of water activity (a w ) and the reduction of pH value are studied as alternatives to the traditional pasteurising ⁄ sterilising treatments. a w of samples of pesto has been reduced using two binary systems of humectants: KCl-fructose and KCl-saccharose. The microbiological stability of samples was assessed through the inoculation of Clostridium perfringens spores. Moreover, pH values, a w and colour parameters were measured. The results have pointed out that a w reduction and controlled temperature of storage inhibited the development of C. perfringens. In particular, run 1 (a w 0.92 and temperature 25°C) allowed a significant increase of the stability time of the samples. The reduction of a w may be a valid alternative to the traditional treatments of stabilisation in maintaining the organoleptic characteristics of the fresh product.

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The extrusion of fatty flour at temperatures less than 100C on the one hand favors less leakage of oil from plant and products, but on the other hand reduces the degree of expansion unless suitable technological coadjuvants are used.Enzymes are generally used in the preparation of bread to mellow gluten and to soften texture. At the moment, there is little information about the use of enzymes to improve the texture of extruded products.The effect of two commercially available enzymes (GRINDAMYL Amylase 1000 and GRINDAMYL Protease 41) on the texture of products obtained from wheat and almond flours extruded at low temperature (54C) was studied.GRINDAMYL Protease 41 was found to affect the rheological characteristics of dough by rapid decreasing the consistency during farinographic analyses and by improving the structure of extrudates with a high lipid content (reduced breaking strength, high% porosity and high water solubility index).