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  • Author or Editor: Z. Kókai x
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In our study we have proven that Bass model depicting the market spread of different products is suitable also for the study and forecast of mineral water consumption. Years in the near future can be predicted trustworthily. Nevertheless, calculation of the optimal parameters is expedient to be executed after every year of consumption data. Our data are belonging from the years of exponent consumption growth (1979–2007), that is to say, from the time before saturation of market, thus one can apply both Bass model and exponent model. We made forecasts for the current forthcoming years by the Bass model.

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In the field of product development and quality assurance flavour lexicons are widely used. These systems include the definition of all attributes and the relevant reference materials or reference samples. With the application of these lexicons more reliable results can be acquired and it can be very helpful to the assessors in sensory analysis. The main purpose of our further research was to establish a flavour language for table margarines. A well-trained margarine expert panel was already established and also an appropriate sensory method (QDA) was chosen. However, the applied sample presentation design also has a strong influence on the results. In this study the effect of two types of test protocols were compared on the performance of the expert panel. The results of the sensory panel were monitored using univariate (F-plot, MSE-plot, p*MSE-plot) and multivariate statistical methods (Tucker-1 correlation loading plot) by PanelCheck. With application of the side-by-side protocol (SBS) the panel agreement and the ability to discriminate the samples and the repeatability of the panel were considerably improved against using the sequential monadic presentation protocol (SM). The explained variance of the first occasion was 74.8% and in case of the application of SM was 55% for PC1.

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The present study investigated how sighted and blind sensory assessors evaluated the quality of various apple varieties: Regal Prince (Gala Must), Jonagold Schneica (Jonica), Watson Jonathan, Golden Reinders and Generos. A total of 80 sighted and 12 blind people participated in the study, in three groups (sighted people without blindfolds, sighted people with blindfolds, blind people). The preference of sensory attributes (size, shape, colour, texture, taste and odour) was evaluated on a six-category scale. The data were analysed using single-factor (ANOVA, LSD95%, 99%) and multi-factor (Cluster analysis, ANOVA, LSD95%, 99%) evaluation. The results showed that blind and sighted assessors made similar judgements on external attributes perceptible by touch (size, shape), but differed in their evaluation of certain quality factors (flavour, taste), resulting in opponent patterns of preference on some apple varieties (Generos, Jonagold Schneica). A further conclusion of the experiment is that there was less deviation between the judgements of sighted assessors when they saw the apples than when they were blindfolded. The background of this phenomenon might be explained by the uncertainty and disturbed perception, which lead to inconsistent judgements.

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Our study involved assessing new Hungarian multi-resistant apple cultivars (‘Artemisz’, ‘Hesztia’, ‘Rosmerta’, and ‘Cordelia’) and two commercial cultivars (‘Watson Jonathan’ and ‘Prima’). The samples were evaluated by a trained assessor panel applying computer supported profile analysis with 20 descriptive sensory parameters (using ProfiSens sensory assessment software). Beside the profiles of each cultivar we also showed the significant differences between the cultivars (LSD95%, LSD99%). The nutritional values were analysed using the MANOVA statistical method, the effects of significant factors on measured values were evaluated by using Tukey (P=0.05) post-hoc test, and we determined the homogeneous and heterogeneous groups based on that. Our study showed that PCA bi-plots containing sensory and instrumental value loadings together with the scores of apple cultivars make the complex relationships of each cultivar available for comparison. The results clearly showed that the intensity of the sour taste is inversely proportional to the carbohydrate-acid ratio determined by measurements. The flesh firmness and pectin content values obtained by instrumental measurements were found to be strongly correlated sensory parameters on crispness, texture, and ripeness. PCA plots proved to be very useful in demonstrating the parallelisms between instrumental-instrumental (TPC/FRAP) and sensory-sensory (shade/colour) parameter pairs, too. Our aggregated results show that the new Hungarian resistant apple cultivars have almost as good as or even better nutritional values than ‘Prima’ and ‘Jonathan’ (the latter dominated the Hungarian apple production for several decades). The new multi-resistant cultivars renew the range of apple cultivars available on the market, and they introduce new flavours to consumers.

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The efficacy of 1-MCP on apricots at different treatment temperatures and days after harvest during 6 weeks of storage at 1 °C was investigated. On the 1st, 3rd, or 5th day after harvest, fruit were treated with 1-MCP at 1 °C for 24 hours. In order to evaluate the effect of temperature, apricots were exposed to 1-MCP at 1, 10, and 20 °C (on the 1st day after harvest). 1-MCP application reduced the ethylene and CO2 production and delayed softening. Fruit treated on the 1st day after harvest presented the highest firmness at the end of the experiment. No significant effect of treatment temperatures on apricot quality was observed. The time period between harvest and 1-MCP application could be delayed until the 5th day after harvest. Results showed that 1-MCP extended the storage life and maintained the overall quality of apricot during storage and shelf-life.

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Abstract

Grafting is an effective tool in intensive vegetable growing systems that provides standard quality and yield. In the present study, the effect of two rootstocks (‘Capsifort F1’ and ‘Snooker F1’) on two commercial varieties (‘SV9702 F1’ and ‘Karpex F1’) grown on two media (soil and coconut fibre) was evaluated. During our 2-year study, those instrumental attributes, which have a dominant effect on the chosen chemical components of fruit quality (total soluble solids and titratable acidity) were investigated. Sensory tests were also implemented in order to identify any changes due to the applied technological combinations. Sensory profile analysis was used to identify the descriptive attributes and their perceived intensities. Panellists worked in individual booths with standard lighting, test results were recorded with the Profisens software. In general, it can be concluded that the major instrumental and sensory parameters did not deteriorate as a result of grafting and the application of coconut fibre medium. Some attributes were identified, where the grafted plants on coconut fibre medium showed higher values, namely flesh thickness and shape. Based on our results, grafting and the application of coconut medium is a feasible technological development for growers and agri-business companies.

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In the past decades many papers were published on the nutritional effect and bioactive components of edible mushrooms. The fungi are able to accumulate secondary metabolites, for example, phenolic compounds, polyketides, terpenes and steroids. In case of mushrooms the button mushrooms are preferred in the Eastern-European region. Therefore white and cream type button mushroom (Agaricus bisporus) and different A. subrufescens (syn. A. blazei) cultivars were cropped, total phenolic content and antioxidant capacity (FRAP) were measured in two years of experiments. To develop the description method of mushroom products, software-supported profile analysis was applied to characterize them. The aim of the research was to compare the sensory profiles of the samples, and to find those characteristics, they actually differ in.

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In this study five commercial product types (frozen sweet corn, fresh champignon, hazelnut chocolate bar, non-carbonated bottled water and Sedum species) were evaluated by two different sensory methods to determine how does the brand/type/variety knowledge influence the sensory perception based product judgement. One of the used methods is the blind sensory test where the samples have random 3-digits code and the remarkable signs are eliminated. The second is the test with knowledge of brand where the participants can see the brands and the package of the products. After the evaluation one-way ANOVA was conducted to identify the non-significant attributes. As the second step of the analysis least square difference method was used to determine which attributes are different at 95% or 99% significance level. During data analysis the common profile plots of the samples were created. The results of the study showed that there is only one sample (hazelnut chocolate bar) where significant difference appeared between the methods used.

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In the case of a widely used spice — Origanum vulgare subsp. hirtum — the effect of different drying methods (natural, and by using dryers at temperatures of 30°C, 40 °C, 45°C) was investigated referring to the essential oil amount and composition in the final material. The sensory characteristics of olive oils flavoured by the oregano samples were also determined. The essential oil amount and the area percentage of its main component — carvacrol — were significantly influenced by the different drying temperatures. Compared to the natural way of drying in the case of the essential oil content the drying temperature of 40°C and 45°C was preferable for the higher amounts. Referring to the carvacrol area percentage the drying temperature of 30°C resulted in the highest amounts (89.74±0.28%), that was affirmed by the sensory analysis as well; based on the taste descriptions the consumers found it the most pungent one. According to our results sensory analysis data in most of the cases corresponds to the GC-MS measurements and give a much more complex characterisation of a spice.

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