Bell pepper maturity determination by ultrasonic techniques

2010 ◽  
Vol 6 (1) ◽  
pp. 17-34 ◽  
Author(s):  
Timea Ignat ◽  
Amos Mizrach ◽  
Ze’ev Schmilovitch ◽  
József Felföldi

Ultrasonic wave attenuation within the flesh of intact greenhouse-grown pepper (Capsicum annum L.) fruits was measured during growth, to try to correlate this attenuation with quality-related physical properties: firmness, dry weight percentage (DW%) and total soluble solids (TSS) contents, and chemical composition. Twenty examples of each of three cultivars were picked weekly during a 7-week growth period, and weight, color, and ultrasonic wave attenuation were recorded, to nondestructively trace the changes during growth, and each intact pepper was then subjected to a relaxation test to determine firmness. Then, small samples of fruit flesh were destructively analyzed to determine DW% and TSS.During the 55th to the 65th day after flowering the fruits of all three cultivars reached their maximum weight, color started to change, and DW% and TSS started to increase rapidly; and the fruits were nondestructively examined by mechanical relaxation and ultrasonically. Principal component regression (PCR) analysis revealed significant (95%) correlation between ultrasonic attenuation, TSS and physical parameters. A TSS prediction model was developed for all three cultivars.

Geophysics ◽  
2008 ◽  
Vol 73 (2) ◽  
pp. N9-N18 ◽  
Author(s):  
Jun Matsushima ◽  
Makoto Suzuki ◽  
Yoshibumi Kato ◽  
Takao Nibe ◽  
Shuichi Rokugawa

Often, the loss mechanisms responsible for seismic attenuation are unclear and controversial. We used partially frozen brine as a solid-liquid coexistence system to investigate attenuation phenomena. Ultrasonic wave-transmission measurements on an ice-brine coexisting system were conducted to examine the influence of unfrozen brine in the pore microstructure on ultrasonic waves. We observed the variations of a 150–1000 kHz wave transmitted through a liquid system to a solid-liquid coexistence system, changing its temperature from [Formula: see text] to –[Formula: see text]. We quantitatively estimated attenuation in a frequency range of [Formula: see text] by considering different distances between the source and receiver transducers. We also estimated the total amount of frozen brine at each temperature by using the pulsed nuclear magnetic resonance (NMR) technique and related those results to attenuation results. The waveform analyses indicate that ultrasonic attenuation in an ice-brine coexisting system reaches its peak at [Formula: see text], at which the ratio of the liquid phase to the total volume in an ice-brine coexisting system is maximal. Finally, we obtained a highly positive correlation between the attenuation of ultrasonic waves and the total amount of unfrozen brine. Thus, laboratory experiments demonstrate that ultrasonic waves within this frequency range are affected significantly by the existence of unfrozen brine in the pore microstructure.


Author(s):  
A J Fletcher ◽  
A Fioravanti

A mixture of polyborosiloxane and silicon carbide abrasive has been agitated using an ultrasonic system. The passage of the ultrasonic wave through this mixture resulted in an increase in temperature due to conversion of energy from the ultrasonic wave into heat. This investigation was initially concerned with the calculation of the heat-generation term, from a knowledge of the attenuation of the acoustic wave. The second stage of the analysis involved the solution of the relevant transient heat-transfer equations for conduction and convection with internal heat generation. The solution to these equations was obtained using a numerical technique. Temperatures at various positions within the system were measured using suitable equipment. These experimental data were compared against the results of the calculation and it was found that significant discrepancies existed between the two sets of results when the analysis considered heat generation as a sole function of wave attenuation. In an attempt to improve the correlation between calculated and measured temperatures the analysis was developed to include a heat-generation term acting at the interface between the sonotrode and the transmission medium. Such heat generation would be produced by frictional heating at the interface, and this would be associated with poor coupling between the acoustic source and the medium. It was found that the correlation between calculated and measured temperatures improved greatly on adoption of the frictional heating analysis, which leads to the suggestion that heating within the medium is a function of both ultrasonic attenuation and frictional heating. For the conditions specified the latter appears to have a dominant role.


1983 ◽  
Vol 44 (C9) ◽  
pp. C9-337-C9-340 ◽  
Author(s):  
R. L. Smith ◽  
W. N. Reynolds ◽  
S. Perring

Foods ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 612
Author(s):  
Vânia Silva ◽  
Sandra Pereira ◽  
Alice Vilela ◽  
Eunice Bacelar ◽  
Francisco Guedes ◽  
...  

Sweet cherry (Prunus avium L.) is a fruit appreciated by consumers for its well-known physical and sensory characteristics and its health benefits. Being an extremely perishable fruit, it is important to know the unique attributes of the cultivars to develop cultivation or postharvest strategies that can enhance their quality. This study aimed to understand the influence of physicochemical characteristics of two sweet cherry cultivars, Burlat and Van, on the food quality perception. Several parameters (weight, dimensions, soluble solids content (SSC), pH, titratable acidity (TA), colour, and texture) were measured and correlated with sensory data. Results showed that cv. Van presented heavier and firmer fruits with high sugar content. In turn, cv. Burlat showed higher pH, lower TA, and presented redder and brightest fruits. The principal component analysis revealed an evident separation between cultivars. Van cherries stood out for their sensory parameters and were classified as more acidic, bitter, and astringent, and presented a firmer texture. Contrarily, Burlat cherries were distinguished as being more flavourful, succulent, sweeter, and more uniform in terms of visual and colour parameters. The results of the sensory analysis suggested that perceived quality does not always depend on and/or recognize the quality parameters inherent to the physicochemical characteristics of each cultivar.


2020 ◽  
Vol 75 (12) ◽  
pp. 1077-1084
Author(s):  
Bhawan Jyoti ◽  
Shakti Pratap Singh ◽  
Mohit Gupta ◽  
Sudhanshu Tripathi ◽  
Devraj Singh ◽  
...  

AbstractThe elastic, thermal and ultrasonic properties of zirconium nanowire (Zr-NW) have been investigated at room temperature. The second and third order elastic constants (SOECs and TOECs) of Zr-NW have been figured out using the Lennard–Jones Potential model. SOECs have been used to find out the Young’s modulus, bulk modulus, shear modulus, Poisson’s ratio, Pugh’s ratio, Zener anisotropic factor and ultrasonic velocities. Further these associated parameters of Zr-NW have been utilized for the evaluation of the Grüneisen parameters, thermal conductivity, thermal relaxation time, acoustic coupling constants and ultrasonic attenuation. On the basis of the above analyzed properties of Zr-NW, some characteristics features of the chosen nanowire connected with ultrasonic and thermo-physical parameters have been discussed.


Foods ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 1101
Author(s):  
Jiovan Campbell ◽  
Ali Sarkhosh ◽  
Fariborz Habibi ◽  
Pranavkumar Gajjar ◽  
Ahmed Ismail ◽  
...  

Biochemical juice attributes and color-related traits of muscadine grape genotypes have been investigated. For this study, 90 muscadine genotypes, including 21 standard cultivars, 60 breeding lines, and 9 Vitis x Muscadinia hybrids (VM), were evaluated. The biochemical properties of total soluble solids (TSS), titratable acidity, and TSS/Acid (T/A) ratio showed modest diversity among genotypes with a range of 10.3 °Brix, 2.1 mg tartaric acid/L, and 4.6, respectively. Nonetheless, the pH trait exhibited a tight range of 0.74 among the population with a minimum and maximum pH of 3.11 ± 0.12 and 3.85 ± 0.12. Color-related traits showed more deviation between individuals. Total anthocyanin content (TAC), luminosity index (L*), hue angle (h°), and chroma index (C*) displayed a range of 398 µg/g DW, 33.2, 352.1, and 24, respectively. The hierarchical clustering map classified the population into two large groups of colored and non-colored grapes based on L* and h°, suggesting the predominance of these two characters among the population. The colored berries genotypes clade was further divided into several sub-clades depending on C*, TAC, and TSS levels. The principal component analysis (PCA) separated the four-color characteristics into two groups with a negative correlation between them, L* and C* versus TAC and h°. Further, PCA suggested the positive influence of acidity in enhancing the different nutraceutical components. Despite the nature of anthocyanins as a member of phenolic compounds, a lack of significant correlation between TAC and nutraceutical-related traits was detected. The dissimilatory matrix analysis highlighted the muscadine individuals C11-2-2, E16-9-1, O21-13-1, and Noble as particular genotypes among the population due to enhanced color characteristics.


Geophysics ◽  
2014 ◽  
Vol 79 (3) ◽  
pp. V115-V130 ◽  
Author(s):  
Jun Matsushima ◽  
Makoto Suzuki ◽  
Ippei Matsugi ◽  
Yoshibumi Kato ◽  
Shuichi Rokugawa

It is important to obtain reliable attenuation results from experimental data to elucidate the physical mechanism responsible for ultrasonic wave attenuation. For attenuation estimation, a time window is often used to compute the frequencies of the direct-arrival waveforms. However, the effect of windowing distorts the spectral distribution due to a spectral leakage effect, degrading the attenuation estimates. We propose a method that enables accurate measurement of ultrasonic attenuation using sweep signals under the assumptions that velocity dispersion can be ignored and the quality factor [Formula: see text] is not dependent on frequency. We obtained the spectral amplitude of the sweep signal in the frequency-time domain using the continuous wavelet transform and estimated attenuation in the time-scale spectrum domain using the spectral-ratio method. This method is independent of the effect of windowing, whereas the windowing effect underestimates the attenuation results. In the absence of noise, the estimated attenuation results using sweep signals are in perfect agreement with the given input values, and the accuracy of the estimated attenuation results from windowed pulse waveforms depends on the extraction window length. However, our numerical experiments demonstrated that the proposed method is largely influenced by the existence of overlapping sweep events such as multiple reflections between the source and receiver transducer. Thus, applicability of the proposed method is limited to highly attenuative media, in which overlapping events are much smaller than direct sweep signals because these multiple reflected events are largely attenuated. Application of the proposed method to laboratory experimental data yielded similar underestimation of the attenuation results due to the windowing effect in the case of highly attenuative media. We also evaluated the usefulness of observing compressed pulse waveforms with shorter duration from the crosscorrelation of sweep waveforms than the case of pulse generation.


2021 ◽  
Author(s):  
Tim Brandes ◽  
Stefano Scarso ◽  
Christian Koch ◽  
Stephan Staudacher

Abstract A numerical experiment of intentionally reduced complexity is used to demonstrate a method to classify flight missions in terms of the operational severity experienced by the engines. In this proof of concept, the general term of severity is limited to the erosion of the core flow compressor blade and vane leading edges. A Monte Carlo simulation of varying operational conditions generates a required database of 10000 flight missions. Each flight is sampled at a rate of 1 Hz. Eleven measurable or synthesizable physical parameters are deemed to be relevant for the problem. They are reduced to seven universal non-dimensional groups which are averaged for each flight. The application of principal component analysis allows a further reduction to three principal components. They are used to run a support-vector machine model in order to classify the flights. A linear kernel function is chosen for the support-vector machine due to its low computation time compared to other functions. The robustness of the classification approach against measurement precision error is evaluated. In addition, a minimum number of flights required for training and a sensible number of severity classes are documented. Furthermore, the importance to train the algorithms on a sufficiently wide range of operations is presented.


2018 ◽  
Vol 33 ◽  
pp. 02075 ◽  
Author(s):  
Tatyana Matseevich

The theme of the research is important because it allows to use hybrid materials as finishing in the high-rise constructions. The aim of the study was the development of producing coloured hybrid materials based on liquid glass, a polyisocyanate, epoxy resin and 2.4-toluylenediisocyanate. The detailed study of the process of stress relaxation at different temperatures in the range of 20-100°C was provided. The study found that the obtained materials are subject to the simplified technology. The materials easy to turn different colors, and dyes (e.g. Sudan blue G) are the catalysts for the curing process of the polymeric precursors. The materials have improved mechanical relaxation properties, possess different color and presentable, can be easily combined with inorganic base (concrete, metal). The limit of compressive strength varies from 32 to 17.5 MPa at a temperature of 20 to 100°C. The values σ∞ are from 20.4 to 7.7 MPa within the temperature range from 20 to 100°C. The physical parameters of materials were evaluated basing on the data of stress relaxation: the initial stress σ0, which occurs at the end of the deformation to a predetermined value; quasi-equilibrium stress σ∞, which persists for a long time relaxation process. Obtained master curves provide prediction relaxation behavior for large durations of relaxation. The study obtained new results. So, the addition of epoxy resin in the composition of the precursor improves the properties of hybrid materials. By the method of IR spectroscopy identified chemical transformations in the course of obtaining the hybrid material. Evaluated mechanical performance of these materials is long-time. Applied modern physically-based memory functions, which perfectly describe the stress relaxation process.


Author(s):  
Adriane Cristina Pereira ◽  
Danielle Godinho de Araújo Perfeito ◽  
Gabriel Pereira de Souza ◽  
Natália Arruda ◽  
Cleiton Gredson Sabin Benett ◽  
...  

The conditions of cultivation and the management of fertilization influence the productivity and the post-harvest quality of cucumbers in an expressive way. In this sense, the aim of this study is to evaluate the physical, chemical and sensorial post-harvest quality of cucumbers for canning purposes submitted to different doses of nitrogen fertilization. The experiment was carried out in a greenhouse at the Goiano Federal Institute (IF Goiano), campus Urutaí and After harvest, the material was sent to the food technology laboratory located in the campus. The soil of the area is classified as Red Latosol according he cucumber cultivar used was the Cucumis sativus L. Kybria F1 hybrid, most suitable for the processing of canned foods. The experimental design was randomized blocks and five treatments (nitrogen doses 0, 50, 100, 150 and 200 kg ha-1), and four replications. The physical parameters fruit length and diameter, fruit fresh matter, production per plant, titratable acidity (TA), pH, soluble solids (SS), moisture, ash content, and SS/TA ratio were evaluated. A sensory analysis was performed using acceptance and ordering-preference tests, in addition to an instrumental evaluation of texture. The application of different doses of nitrogen to cucumber in a protected environment influenced the production per plant and the physical-chemical characteristics of the fruits. However, the sensory quality was not affected. The doses 100 and 150 kg ha-1 of nitrogen is recommended for the production of canned cucumber


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