21 research outputs found
Characterization of Cider Apples on the Basis of Their Fatty Acid Profiles
In the current study, the fatty acids composition of 30 monovarietal apple juices from six cider apple
varieties belonging to two categories was analyzed. The different apple juices were obtained from
three consecutive harvests (1997, 1998, and 1999). The fatty acids concentration in apple juice
together with chemometric techniques such as principal components analysis (PCA), soft independent
modeling of class analogy (SIMCA), and linear discriminant analysis (LDA), allowed us to differentiate
apple juices on the basis of the sweet or sharp category to which the cider apple variety belongs.
Fatty acids such as the unsaturated oleic and linoleic acids, and saturated caprylic, capric, stearic,
and palmitic acids were related to the sweet cider apple category, while pentadecanoic acid is related
to the sharp class
Gas Chromatographic Analysis of Total Fatty Acids in Cider
This paper reports the composition of total fatty acids in an apple beverage, cider. Fatty acids are
present in the free or esterified form and contribute to both the flavor and foam properties of cider.
Fatty acids were separated and identified as methyl esters by GC-MS, and 12 of these were
subsequently determined by GC-FID. The major fatty acids found in cider were caproic, caprylic,
capric, and palmitic acid, the saturated acids predominating over the unsaturated ones. The proposed
method was applied to 59 ciders from three consecutive harvests (1996, 1997, and 1998), which
were made by 19 cider-makers from the region of Asturias (Spain). Linear discriminant analysis of
fatty acids in these samples allowed selection of palmitoleic, pentadecanoic, linoleic, myristic, and
linolenic acid as the most predictive variables to differentiate ciders made from apples grown in
the Asturias region (1997 harvest) and ciders made from apples grown outside this region (1996
and 1998 harvests)
Polymeric Ionic Liquids Derived from L-Valine for the Preparation of Highly Selective Silica-Supported Stationary Phases in Gas Chromatography
A series of silica-supported polymeric ionic liquid (PIL)-based stationary phases derived
from a vinylic L-valine ionic liquid monomer and divinylbenzene (DVB) as the crosslinking agent
have been prepared and studied as gas chromatographic stationary phases. These coated gas
chromatographic columns exhibited good thermal stabilities (230–300 ◦C) and high efficiencies
(1700–2700 plates/m), and were characterized using a linear solvation parameter model in order to
understand the effects of the amount of DVB on the features of the resulting composite systems.
Their retention behavior and separation efficiencies were demonstrated using the Grob test. By tuning
the crosslinking degree for the IL-derived stationary phase, the separation selectivity and resolution
of different compounds were improved. The different retention behaviors observed for many analytes
indicate that these stationary phases may be applicable as new types of GC stationary phases
A novel method for the determination of total 1,3-octanediols in apple juice via 1,3-dioxanes by solid-phase microextraction and high-speed gas chromatography
In this work, a novel, simple and fast method based on solid-phase microextraction (SPME) followed by
high-speed gas chromatography (HSGC) was developed for the analysis of total 1,3-octanediols in apple
juices by means of derivatization reaction to volatile 1,3-dioxanes. The derivatization reaction, SPME
conditions, glycosidically bound fraction and 1,3-nonanediol as a surrogate standard were studied. The
formation of 1,3-dioxanes from 1,3-diols was confirmed by GC–MS. The method was validated obtaining
a regression coefficient (r2) of 0.9996, precisions between 0.3 and 9.8%, extraction recoveries in the
range 94.7–112.2% and LOD of 2.9 g l−1. Experimental design has been employed in the optimization
of extraction factors and robustness assessment. The method was applied to the analysis of 21 Asturian
apple varieties finding a double reciprocal relationship between the concentrations of saturated and
unsaturated 1,3-octanediol