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Introduction: Alkaline treatments extract hemicellulose from the fibers, which can be reused in the manufacture of other materials, and the cellulosic portion can be applied as reinforcement in a composite. This way, all components of the fibers are utilized. Method: In this work, curaua fibers (Ananas erectifolius) were treated with potassium hydroxide (KOH) to solubilize part of the hemicellulose and lignin, and the cellulose-rich fibers were used to manufacture composites with unsaturated polyester, which were characterized to investigate the effect of the treatment on their properties. Results: The alkaline treatment removed large portions of hemicellulose and significantly degraded the crystalline cellulose and lignin, resulting in a small increase (2.4%) in overall crystallinity and with a negative impact on their thermal stability. SEM images showed defibrillation of the treated fiber and fibril separation, increasing roughness and surface contact area. Conclusions: In all, although the alkaline treatment substantially modified the fibers and no significant changes were observed in the mechanical properties of the composite, the total removal of hemicellulose was found to affect the integrity of cellulose fibers making harder their application as reinforcement. However, the higher cellulose content could be useful for other applications. [ABSTRACT FROM AUTHOR]

This article describes for the first time at the industrial level the temperature rise that occurs inside the processing tank during the lye treatment. Relationships between variables that define the lye treatment have been determined from the study of the thermal characteristics of this process. The initial temperature influences other variables of this treatment, such as its duration or the slope of the linear increase of temperature produced. The study estates that this generation of heat can be principally caused by the alkaline hydrolysis reactions that occur in the interior of the fruit and, to a lesser extent, by the dilution of sodium hydroxide solution with water present in the pulp of the olives. [ABSTRACT FROM AUTHOR]

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Two new procedures for the elaboration of alkali-treated green table olives, without fermentation, preserved by sterilization or pasteurization were studied. In each case, the aim was to obtain a product with good quality and guaranteed safety. In the sterilized product, it was demonstrated that by including a pitting step during elaboration, a product was obtained with both flavour and texture similar to those of «green ripe olives», but without the need to apply an excessive number of washes. Alkalizing agents added to the packing solution negatively affected the organoleptic olive properties. In case of the pasteurized product, a pitting step during elaboration was also demonstrated to be effective in improving olive flavour. Fruit texture was not significantly affected by this step. Both herbal extracts and monosodium glutamate added to the packing solution successfully masked the «cooked» flavour of olives associated with pasteurisation. [ABSTRACT FROM AUTHOR]