This article describes the effect of the nixtamalization process on phytic acid, calcium, iron and zinc contents in 11 varieties of whole maize and their germ and endosperm. Maize samples were cooked in water with 1.2% lime for 75 min at 96 C, soaked for 10 h and washed. Half of the whole cooked kernel was dried and the other half was dissected into germ and endosperm, which were also dried. These samples were analyzed for phytic acid, calcium, iron and zinc. The germ contained the highest concentration of phytic acid and the endosperm the lowest. Phytic acid in the whole grain, endosperm and germ decreased upon nixtamalization. The loss in whole grain varied from 4.4 to 27.9%; from 19.7 to 59.8% in the endosperm and from 8.0 to 35.3% in the germ. Significant statistical differences were found for varieties, processing and for their interaction (varieties  processing). Calcium was present in higher amounts in the germ before and after nixtamalization. This process increased the level of calcium about 18 times in the whole grain and the endosperm, and about 24 times in the germ. The differences were significant due to variety, processing and their interaction (variety  processing). The germ contained higher amounts of iron in both its raw and nixtamalized states. The whole grain and the endosperm lost iron due to the alkaline cooking process. Statistical analyses showed significant differences due to varieties and the process. As for iron, the germ contained higher amounts of zinc in both raw and nixtamalized forms, than the endosperm. There was a loss in zinc content in the endosperm processed by lime cooking, but not in the germ.Se ha analizado el efecto del proceso de nixtamalizacio´n en el contenido de a´cido fı´tico, calcio, hierro y cinc de 11 variedades de maı´z entero, del germen y del endospermo. Las muestras de maı´z se cocieron en agua con 1,2% de hidro´xido de calcio durante 75 min a 96 C, se dejaron en remojo durante 10 h y se lavaron con agua. La mitad del maı´z entero cocido se deshidrato´y en la otra mitad se separaron el germen y el endospermo, que tambie´n se deshidrataron. En todas las muestras se analizaron el a´cido fı´tico, calcio, hierro y cinc. El germen tuvo la mayor concentracio´n de a´cido fı´tico y el endospermo la menor. El a´cido fı´tico en el grano entero, endospermo y germen disminuyo´debido a la nixtamalizacio´n. La pe´rdida en el grano entero vario´entre 4,4 y 27,9%, en el endospermo de 19,7 a 59,8% y en el germen de 8,0 a 35,3%. Se encontraron diferencias estadı´sticamente significativas entre variedades, el proceso de coccio´n y tambie´n en la interaccio´n de estas variables. El germen fue la fraccio´n con mayor cantidad de calcio en el germen antes y despue´s de la nixtamalizacio´n. El proceso aumento´la concentracio´n de calcio en aproximadamente 18 veces en el grano entero y endospermo, y alrededor de 24 veces en el germen. Las diferencias fueron significativas segu´n la variedad, el proceso y en la interaccio´n proceso x variedad. En el germen el contenido fue mayor tanto ...

Increasing applications and markets for essential oils could bring new opportunities for cost-effective and sustainable management of unused forestry biomass; however, better knowledge of the production and application of such essential oils is necessary. The objective of this work is to contribute to greater knowledge of the essential oil production on a pilot scale from foliage biomass of wild shrubs and tree residues produced in some forestry enhancement operations and to study their antioxidant capacity (ORAC—oxygen radical absorbance capacity). Fresh biomass (twigs) of seven species (E. globulus, E. nitens, P. pinaster, P. sylvestris, R. officinalis, C. ladanifer, and J. communis) was manually collected in Spain in two different periods and was ground at 30 mm and distilled in a 30 L stainless steel still with saturated steam. The essential oil components were identified by GC–MS and quantified by GC–FID, and their antioxidant activity was determined with the ORAC method. Promising results on essential oil yield were obtained with E. globulus, E. nitens, R. officinalis, and J. communis. All essential oils studied exhibited antioxidant capacity by the ORAC assay, particularly that from C. ladanifer. Moreover, oxygenated sesquiterpenes contents, one of the minor components of oils, were significantly correlated with ORAC values.

Cistus ladanifer is a Mediterranean native plant from which valuable products, such as essential oil, are obtained. Manual harvesting of the plants in wild shrublands is usual during short periods of time. Their mechanised harvesting could increase the volume of harvested plants and prevent fires, further storage of the plants collected being necessary. The objective of this work is to study the influence of the storage period of mechanically harvested bales on the essential oil yield and qualitative composition. The harvesting trials were carried out with an adapted commercial harvester baler and the storage of the bales was performed indoors during 1–7 days, 15–30 days and 100–120 days. Afterwards, the bales were crushed (30 mm) and distilled in a 30 litre stainless steel still with saturated steam (0.5 bar). The essential oil components were identified by GC-MS and quantified by GC-FID. The storage of mechanically harvested Cistus ladanifer does not decrease the oil yield of steam distillation on a pilot scale. However, it leads to differences in the quantitative composition of the essential oils, decreasing the total monoterpene compounds content and increasing that of oxygenated sesquiterpenes, especially when the biomass is stored for 100–120 days, without affecting its qualitative composition.