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In the case of organic production the quality assessment of the fruits and vegetables is especially important. Monitoring of the maturation and ripening process, early detection of diseases, decision about harvest date and postharvest treatment need reliable, objective and – preferably – non-destructive quality testing methods. Dynamic hardness or stiffness measurement methods (resonance, impact, wave propagation) offer very useful tools in this field, but with strong limitations in applicability area and/or physical interpretation of the measured parameters. Our objective was to develop method and appropriate portable instrumentation to measure surface hardness – as quality measure – with a nondestructive method.

The computer controlled instrument has an electromagnetically excited impactor fitted with a piezoelectric acceleration sensor, a signal conditioner and A/D converter. To ensure the uniform contact behavior (contact area) between the impactor and the tested produce of wide range of shape, spherical head was applied. Conclusively, Hertz contact theory is to be applied for evaluation of the impact signal. Instead of using empirical “hardness index” – as in the case of several existing instruments – our objective was the physical interpretation of the contact phenomena. The measured acceleration signal was mathematically processed to calculate real physical parameters (force, speed, deformation), and to characterize the process similarly to the widely used texture analyzers, penetrometers. A new hardness parameter – “dynamic elastic modulus” – was introduced. According to the methodological investigations, the measurement was found to be perfectly non-destructive for a wide range of products. Conclusively, the developed method offers a useful tool for quality evaluation of organic horticultural products.

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Acta Chromatographica
Authors:
Gobinda Chandra Acharya
,
Naresh Ponnam
,
Meenu Kumari
,
Tapas Kumar Roy
,
Kodthalu Seetharamaiah Shivashankara
, and
Manas Ranjan Sahoo

Coriandrum sativum L. collected from the local market were maintained in the greenhouse at Central Horticultural Experiment Station (CHES), Bhubaneswar, India. Fresh Eryngium leaves and branches were assessed for various phytochemical compositions and

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). Effect of grafting eggplant ( Solanum melongena L.) on its selected useful characters . Bulletin UASVM Horticulture , 72 ( 2 ): 318 – 326 . Bie , Z. , Azher Nawaz , M. , Huang , Y. , Lee , J.-M. and Colla , G. ( 2017 ). Importance and use

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1998 104 277 287 E. Szarka , Szent István University, Faculty of Horticultural Science, Department of Genetics and

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Differential scanning calorimetry (DSC) is the most widely used thermal analytical technique in food research and it has a great utility in quality assurance of food. Proteins are the most studied food components by thermal analysis including studies on conformation changes of food proteins as affected by various environmental factors, thermal denaturation of tissue proteins, food enzymes and enzyme preparations for the food industry, as well as effects of various additives on their thermal properties. Freezing-induced denaturation of food proteins and the effect of cryoprotectants are also monitored by DSC. Polymer characterization based on DSC of polysaccharides, gelatinization behaviour of starches and interaction of starch with other food components can be determined, and phase transitions during baking processes can be studied by DSC. Studies on crystallization and melting behaviour of fats observed by DSC indicate changes in lipid composition or help characterizing products. Thermal oxidative decomposition of edible oils examined by DSC can be used for predicting oil stability. Using DSC in the freezing range has a great potential for measuring and modelling frozen food thermal properties, and to estimate the state of water in foods and food ingredients. Research in food microbiology utilizes DSC in better understanding thermoadaptive mechanisms or heat killing of food-borne microorganisms. Isothermic microcalorimetric techniques provide informative data regarding microbial growth and microbial metabolism.

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.A. , Syukur , M. , Melati , M. , and Guntoro , D. ( 2016 ). Selection of shade-tolerant tomato genotypes . Journal of Applied Horticulture , 18 ( 2 ): 154 – 159 . https://doi.org/10.37855/jah.2016.v18i02.27 . Sun , G. , Ding , Y. , Wang , X

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Abstract  

Due to the disaster at the Chernobyl nuclear power station /26.04. 1986, USSR/ the radioactive contamination level /e.g.,134Cs,137Cs/ of the biosphere in Hungary increased significantly. The external -dose burden from the contaminated ground surface and atmosphere, and the radioactive isotopes taken up directly through the leaves and indirectly from the soil through the root system had a low-dose effect on the plants which was in the dose-range of stimulation /biopositive effect/.

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Progress in Agricultural Engineering Sciences
Authors:
Mai Sao Dam
,
Vuong Duc Nguyen
,
Tamás Zsom
,
Lien Le Phuong Nguyen
, and
Géza Hitka

to meet consumers' demand is necessary. Most of horticultural produce are not consumed immediately after harvest. In supply chain, ethylene-sensitive and ethylene-producing commodities are usually stored together. The high ethylene concentration in

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an important trait. Our next goal is to adopt further image analysis software already involved in the characterization of horticultural crops and describe large numbers of grapevine cultivars based on the size and shape attributes of the berry

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A new process, bilateral band compression has been used to increase the sensitivity of detection of minor components of a mixture. After band-shaped sample application, fully off-line OPLC separation, and drying, the separated bands were compressed bilaterally, in parallel, perpendicular to the direction of development, by use of a strong eluent and capillary driven chromatography. To introduce the eluent on to the layer for band compression a simple manual tool equipped with parallel foam strips was constructed. A mixture of xanthine standards (caffeine 0.998 mg mL −1 , theophylline 1 μg mL −1 , and theobromine 1 μg mL −1 ) and black tea leaf extract were used to test the efficiency of detection after bilateral band compression. After band compression 20 ng theophylline and theobromine could be detected by densitometry in the xanthine standard mixture at a loading of 20 μg/10 mm whereas they were not visible in the original, uncompressed chromatogram.

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