Authors:V. Hajnal, L. Szalay, Sz. Németh, G. Ficzek, G. Bujdosó, and M. Tóth
Apricot is an important fruit species in Hungary both for fresh consumption and processing. Physical parameters and change of nutrients of nine apricot cultivars were studied during the ripening period. Four Hungarian and five North-American apricot cultivars were chosen for investigation. Changes in the physical parameters were measured by three different methods (Magness-Taylor hand penetrometer, Bookfield CT3 Texture Analyser with TA 44 and TA 9 measuring head). Significant differences in flesh firmness among the cultivars were observed mainly at the beginning of ripening time. Adhesiveness, cohesiveness and chewiness of the fruits decreased continuously during ripening. The studied cultivars showed significant differences in these traits. Sugar and acid contents were also measured during ripening. The cultivars showed small differences in sugar content and bigger differences in acid content of the fruits. Our data measured and collected during this study can be useful in characterizing the apricot cultivars studied. Changes in the texture parameters responsible for transportability and the technological usability of the fruits were described across the whole ripening period. Our results may help growers as well as food technologists to determine the optimum harvest date of cultivars intended to be used for different purposes.
Authors:E. Kovács, P. Merész, Z. Kristóf, and E. Németh-Szerdahelyi
Colour, texture, pectin autolysis, membrane permeability and microstructure (SEM, TEM), β-galactosidase and polygalacturonase were studied in apricots (cv. Magyar kajszi) harvested in mature green, straw yellow, bright orange and deep orange stages. The L* increased from mature green to straw yellow then decreased from straw yellow to deep orange state. The a* values increased with ripening. The bright and deep orange apricots were significantly softer than the mature green and straw yellow ones and the membrane permeability increased with ripening. The presence of β-galactosidase enzyme was proved by immunoblotting analysis using monoclonal anti-β-galactosidase clone GAL-13 (Sigma) in all ripening stages. The enzyme activity was very low in mature green stage and increased significantly (P>95%) with increasing ripeness and during storage. The PG activity was very low in the mature green apricot. A significant (P>95%) increase was observed in the straw yellow apricot and in the riper fruits. The mature green apricot showed a regular, the straw yellow and bright orange samples showed a moderately regular tissue structure, while the tissue of the deep orange apricot collapsed (SEM). The cell wall and the middle lamella of the green apricot (TEM) were intact. Generally, there were intact cytoplasm membranes with some damaged parts. In the straw yellow apricot, the cell wall started to loosen, the middle lamella lost pectic polysaccharides. The structure of the cytoplasm was not recognisable, the tonoplast and the cytoplasm membrane were injured. The cell wall of the bright orange apricot was similar to that of the straw yellow ones. The middle lamella dissolved and hairy, fibrillar structure of cell wall was found in the deep orange samples.
Authors:Mahmood Hasan Al-Hafadhi and Gyorgy Krallics
simulation has been widely used [ 10–18 ]. In this study, the prediction of residual stresses in a dissimilar pipe weld joint made of E355K2 and P460NH_1 is studied by using 2-D finite element method. The simulation hardness of the weld joint is used to
analysis (DMA), three-point bending test, and Brinell’s hardness. The influence of poly(ester) structure on cross-linking density ( ν e ), tgδ max , tgδ max height, storage modulus ( ), hardness, flexural modulus at bending ( E mod ), deflection at
Authors:Wisdom Okechukwu Egbujuo, Placid Ikechukwu Anyanwu, and Henry Chinedu Obasi
, there is a limit to the mechanical properties of rubber that can be achieved by mere vulcanization [ 2 ]. The introduction of fillers to natural rubber improves its properties such as high stiffness, compression strength, hardness and other physical
Authors:F. Khalfallah, Z. Boumerzoug, S. Rajakumar, and E. Raouache
that friction time, friction pressure, and forging pressure have a strong effect on tensile strength, microstructures, and hardness of joints. In addition, Alves et al. [ 18 ] studied the rotary friction welding of AA 1050 aluminum alloy to AISI 304
Authors:Aidin Pahlavan, Mohammad Hassan Kamani, Amir Hossein Elhamirad, Zahra Sheikholeslami, Mohammad Armin, and Hanieh Amani
canonical analysis. Their results revealed the generation of two simple models, which could simultaneously predict the bread loaf volume and crumb hardness. Ohm and Chung (1999) evaluated flour gluten, pasting, and mixogram parameters of twelve hard winter