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Dit dossier “Nieuw-Zeeland, ver en toch dichtbij” omvat de volgende artikelen: 1) De wereld van de andere kant bekeken. 2) Meer koeien dan mensen. 3) Landbouw en natuur. 4) Wild dat geen wild is.

The effect of microwave processing on the characteristics of kiwifruit puree was evaluated by applying various gentle treatments. Different combinations of microwave power/processing time were applied, with power among 200-1,000 W and time among 60-340 s, and various sensory and instrumental measurements were performed with the aim of establishing correlations and determining which instrumental parameters were the most appropriate to control the quality of kiwi puree. The water and soluble solids of the product, 83 and 14/100 g sample, respectively, did not change due to treatments. For sensory assessment, an expert panel was previously trained to describe the product. Fourteen descriptors were defined, but only the descriptors 'typical kiwifruit colour', 'tone', 'lightness', 'visual consistency' and 'typical taste' were significant to distinguish between kiwifruit puree samples. The instrumental analysis of samples consisted in measuring consistency, viscosity, colour and physicochemical characteristics of the treated and fresh puree. Applying intense treatments (600 W-340 s, 900 W-300 s and 1,000 W-200 s) through high power or long treatment periods or a combination of these factors, mainly affects the consistency (flow distance decreased from 5. 9 to 3. 4 mm/g sample), viscosity (increased from 1. 6 to 2. 5 Pa/s), colour (maximun ¿E was 6 U) and taste of the product. As a result, samples were thicker and with an atypical flavour and kiwifruit colour due to increased clarity (L* increased from 38 to 43) and slight changes in the yellow-green hue (h* decreased from 95 to 94). For the instrumental determinations of colour and visual perception of consistency, the most suitable parameters for quality control are the colour coordinates L*, a*, h*, whiteness index and flow distance measured with a Bostwick consistometer. © 2011 Springer Science+Business Media, LLC.

The effect of microwave processing on the characteristics of kiwifruit puree was evaluated by applying various gentle treatments. Different combinations of microwave power/processing time were applied, with power among 200-1,000 W and time among 60-340 s, and various sensory and instrumental measurements were performed with the aim of establishing correlations and determining which instrumental parameters were the most appropriate to control the quality of kiwi puree. The water and soluble solids of the product, 83 and 14/100 g sample, respectively, did not change due to treatments. For sensory assessment, an expert panel was previously trained to describe the product. Fourteen descriptors were defined, but only the descriptors 'typical kiwifruit colour', 'tone', 'lightness', 'visual consistency' and 'typical taste' were significant to distinguish between kiwifruit puree samples. The instrumental analysis of samples consisted in measuring consistency, viscosity, colour and physicochemical characteristics of the treated and fresh puree. Applying intense treatments (600 W-340 s, 900 W-300 s and 1,000 W-200 s) through high power or long treatment periods or a combination of these factors, mainly affects the consistency (flow distance decreased from 5. 9 to 3. 4 mm/g sample), viscosity (increased from 1. 6 to 2. 5 Pa/s), colour (maximun ¿E was 6 U) and taste of the product. As a result, samples were thicker and with an atypical flavour and kiwifruit colour due to increased clarity (L* increased from 38 to 43) and slight changes in the yellow-green hue (h* decreased from 95 to 94). For the instrumental determinations of colour and visual perception of consistency, the most suitable parameters for quality control are the colour coordinates L*, a*, h*, whiteness index and flow distance measured with a Bostwick consistometer. © 2011 Springer Science+Business Media, LLC.

[EN] Shelf life of kiwifruit is short and requires conservation techniques to increase its commercial life. In this sense, the modern techniques used to analyze the changes of the product through the treatment allow developing new products with the specific quality characteristics required. In this work, the structural and physico-chemical changes of kiwifruit through the osmotic dehydration treatment with 61.5% (w/w) sucrose solution at short times from 0 to 300 min were explained. The SAFES (systematic approach to food engineering systems) methodology applied in kiwifruit is useful to obtain the internal composition of each phase, to control the fruit changes through the process, and to determine the behaviors involved in transports. Moreover, the Gibbs free energy, the enthalpy and the entropy estimation of each phase was calculated in order to analyze the irreversibility of the process. (C) 2011 Elsevier Ltd. All rights reserved.

[EN] Dielectric spectroscopy studies have been performed on fresh and osmotically dehydrated kiwifruits (Actinidia deliciosa cv Hayward). The osmotic treatment consisted on the immersion the samples into 65% (w/w) sucrose aqueous solution at 30 °C during different treatment times from 5 to 1440 min. Some physical-chemical parameters were measured in fresh, treated and reposed (24 h at 30 °C) samples. Dielectric spectra were measured in the frequency range from 500 MHz to 20 GHz by an Agilent 85070E Open-ended Coaxial Probe connected to an Agilent E8362B Vector Network Analyzer in the fresh, treated and reposed samples. It has been demonstrated that the dielectric technique is a good method to control the osmotic treatment in kiwifruit. Industrial relevance: The results of this research article are demonstrated to be useful for controlling candying of kiwifruits in bakery industries. Thus, the industrial relevance is clear in order to optimize the osmotic dehydration times and the final quantity of sugars added by using a non destructive technique that can be implemented in process line. Dielectric spectroscopy, which can be considered an emerging technology, has the advantage of being an objective and a rapid technique. For all these reasons we are sending to this journal "Innovative Food Science and Emerging Technologies" our results. © 2011 Elsevier Ltd. All rights reserved.

[EN] Dielectric spectroscopy studies have been performed on fresh and osmotically dehydrated kiwifruits (Actinidia deliciosa cv Hayward). The osmotic treatment consisted on the immersion the samples into 65% (w/w) sucrose aqueous solution at 30 °C during different treatment times from 5 to 1440 min. Some physical-chemical parameters were measured in fresh, treated and reposed (24 h at 30 °C) samples. Dielectric spectra were measured in the frequency range from 500 MHz to 20 GHz by an Agilent 85070E Open-ended Coaxial Probe connected to an Agilent E8362B Vector Network Analyzer in the fresh, treated and reposed samples. It has been demonstrated that the dielectric technique is a good method to control the osmotic treatment in kiwifruit. Industrial relevance: The results of this research article are demonstrated to be useful for controlling candying of kiwifruits in bakery industries. Thus, the industrial relevance is clear in order to optimize the osmotic dehydration times and the final quantity of sugars added by using a non destructive technique that can be implemented in process line. Dielectric spectroscopy, which can be considered an emerging technology, has the advantage of being an objective and a rapid technique. For all these reasons we are sending to this journal "Innovative Food Science and Emerging Technologies" our results. © 2011 Elsevier Ltd. All rights reserved.

[EN] Shelf life of kiwifruit is short and requires conservation techniques to increase its commercial life. In this sense, the modern techniques used to analyze the changes of the product through the treatment allow developing new products with the specific quality characteristics required. In this work, the structural and physico-chemical changes of kiwifruit through the osmotic dehydration treatment with 61.5% (w/w) sucrose solution at short times from 0 to 300 min were explained. The SAFES (systematic approach to food engineering systems) methodology applied in kiwifruit is useful to obtain the internal composition of each phase, to control the fruit changes through the process, and to determine the behaviors involved in transports. Moreover, the Gibbs free energy, the enthalpy and the entropy estimation of each phase was calculated in order to analyze the irreversibility of the process. (C) 2011 Elsevier Ltd. All rights reserved.

[EN] Osmotic dehydration experiments of kiwifruit (Actinidiadeliciosa cv Hayward) were carried out in order to apply a nonlinear irreversible thermodynamic model. Samples were immersed into 65% (w/w) sucrose aqueous solution at 30 degrees C during 5, 10, 15, 20, 30, 45, 60, 90, 120, 180, 250, 320, 400, 720, 1440 min. Some physical-chemical parameters were measured in fresh, treated and reposed (24 h at 30 degrees C) samples. It was possible to apply the enthalpy-entropy compensation coupled to a nonlinear thermodynamic model, obtaining the apparent bulk modulus and explaining the elastic answer of the tissue throughout the osmotic process. The osmotic dehydration also produces losses in the native compounds of kiwifruit such as citric acid and Calcium and Potassium. (C) 2011 Elsevier Ltd. All rights reserved.

De teelt en opkweek van de kiwi wordt besproken. De snoei wordt met illustraties verduidelijkt. Tevens wordt een lijst van rassen gegeven

3 artikelen over de Nieuw-Zeelandse marketing & salesorganisatie Zespri: jaarrond levering van kiwi's en kiwi-promotie met interactief lesmateriaal