Moisture dependence on mechanical properties of pine nuts from Pinus pinea L

[EN] Mechanical properties of pine nut shell are very important in the cracking process. Before industrial cracking shell moisture is adjusted by water soaking in order to avoid the breaking up of the nuts. In this work the moisture dependence of the mechanical properties of pine nut shells were studied in order to improve the industrial cracking process. Relationship between nut size and moisture content was studied and no significant differences were found for shell dimensions at four different moisture levels, 9.79%, 16.71%, 20.98% and 25.05% (dry basis). Compression tests were carried out on pine nuts at nine different moisture contents between 1.38% and 25.48% (db) and their main mechanical parameters were evaluated. Nut shell has a characteristic behavior under compression loading. Rupture force, rupture deformation, elasticity and rupture energy of shell were found to be moisture dependent. Values of rupture force decreased linearly from 0.24 to 0.49 kN, rupture deformation and rupture energy increased initially with moisture until stabilization at asymptotic values of about 1.8 mm and 0.22 J, respectively. Elasticity index of the shell decreased linearly with moisture from 1 to 0.4 kN/mm. (C) 2011 Elsevier Ltd. All rights reserved.Cárcel, LM.; Bon Corbín, J.; Acuna, L.; Nevares, I.; Del Álamo Sanza, M.; Crespo, R. (2012). Moisture dependence on mechanical properties of pine nuts from Pinus pinea L. Journal of Food Engineering. 110(2):294-297. doi:10.1016/j.foodeng.2011.04.018S294297110

Impact of long bottle aging on chemical composition and sensory profile or red wines micro oxygenated with oak adjuncts

Trabajo presentado en el 10th In Vino Analytica Scientia Symposium, celebrado en Salamanca (España), del 17 al 20 de julio de 2017Peer reviewe

Quercus humboldtii (Colombian Oak) Characterisation of wood phenolic composition with respect to traditional oak wood used in oenology

The use of new oak barrels and the demand for oak wood in oenology is increasing. Thus, it is necessary to search for new wood sources to supply the current demand in cooperage. The aim of this work was to study the composition of ellagitannins and low molecular weight phenolic compounds (LMWP) by HPLC-DAD of green wood Quercus humboldtii Bonpl. (Colombian), compared to the species typically used in cooperage Quercus sessiliflora Salisb. (French and Romanian) and Quercus alba L. (USA). In Colombian oak wood, the same LMWP and ellagitannins as in the traditional species were identified. The most abundant LMWP was ellagic acid, and its concentration was lower in Q. humboldtii and Q. alba than in Q. sessiliflora, so these two presented a lower content of phenolic acids. As regards phenolic aldehydes, Colombian oak wood only showed significant differences in the content of coniferyl and sinapic aldehydes in relation to French oak. Finally, the total ellagitannin content of Q. humboldtii was lower than that of European oaks and similar to that of American oak (Q. alba). None of the ellagitannins studied presented significant differences compared to Q. alba. Therefore, Q. humboldtii wood was more similar in terms of phenolic composition to Q. alba than to Q. sessiliflora

Recent advances in the study of grape and wine volatile composition: Varietal, fermentative and ageing aroma compounds

Wine aroma is very complex due to the large number of volatile compounds that it contains. Various aromatic compounds can be distinguished in wine, and they depend on several factors such as grape variety, season, terroir, grape maturity, viticultural practices, fermentation conditions, and conservation, with grape maturity and alcoholic fermentation being the most critical stages. The varietal aromas of wine are composed by the odorous compounds that come from the grape’s own metabolism. The terpenes found in most grape cultivars are alcohols and oxides of 10 carbon atoms, such as geraniol, linalool, citronellol, nerol, and rose oxide, among others. The aging period for a wine involves the development of a series of processes that determine the properties of the end product. Aromatic composition is a key aspect of wine quality. Varietal and pre-fermentative aromas are mainly influenced by grape variety and their state of maturity, viticultural practices, and edaphic and climatic conditions

Effects of the treatment with oak chips on color-related phenolics, volatile composition, and sensory profile of red wines: the case of Aglianico and Montepulciano

The effects of the treatment of two important Italian wines, Aglianico and Montepulciano, with French oak chips were analyzed. The study was focused on the changes of color-related compounds such as anthocyanins and tannins, and of volatile and sensory profiles. An overall characterization of the wines was also performed. With reference to the phenolic profile, the behaviors of the two wines were different due to their different initial phenolic composition. The oak-chip treatments favored the polymerization of anthocyanins and tannins, whose concentrations in the oak-treated Aglianico samples were lower than in the controls (anthocyanins, â\u88\u9284 %; tannins, â\u88\u9271 %), while in the oak-treated Montepulciano wine the decrease concerned only anthocyanins (â\u88\u9257 %). The concentrations of polymeric phenols increased with aging in all the samples and, after 12 months, were higher in oak-treated wines than in the controls (+43 % in Aglianico, +39 % in Montepulciano). After 12 months of aging, the volatile profile of Aglianico oak-treated wines highlighted the highest acid (+68 %), terpene (+371 %), and lactone (+60 %) concentrations, while the oak-treated Montepulciano wine showed higher acid (+15 %), alcohol (+5 %), and lactone (+50 %) concentrations than the control wine. The sensory profile of the treated wines was characterized by high scores assigned to astringency and appearance of the typical oak aromas (woody, vanilla, and spicy notes) and the attenuation of floral and fruity attributes. These changes were responsible for the increase in intensity of the tannic character in Aglianico wine and the improvement of the Montepulciano wine aroma with respect to the corresponding untreated wines