To know and to understand consumers’ preferences is essential in every kind of product development. Consumers make their decision on the basis of numerous factors. In case of mineral waters it is frequently mentioned, that sensory quality is an important attribute of the product. To investigate the real importance of this quality parameter we analysed several mineral waters, which are available on the Hungarian market, with the aim of searching for differences between the products. The applied qualitative method — software-supported profile analysis — is suitable for comparing samples in a much detailed way. Panelists were trained for the use of scales, but they were not selected according to their sensory acuity. This way we simulated the group of consumers — not in a representative, but in a similar way (e.g. average sensory acuity). The aim of the research was to compare the sensory profiles of the samples, and to find those characteristics, in which they actually differ.
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.
Authors:L. Sipos, I. Király, L. Bábel, Z. Kókai, and M. Tóth
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.
Authors:A. Györey, A. Gere, Z. Kókai, P. Molnár, and L. Sipos
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.
Authors:L. Sipos, G. Ficzek, Z. Kókai, and M. Tóth
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.
Authors:Cs. Bojtor, Z. Győri, P. Sipos, L. Radócz, and B. Tóth
The aim of the study was to investigate changes of photosynthetic efficiency, amount of photosynthetic pigments, superoxide dismutase (SOD) enzyme activity, and rate of lipid peroxidation in bean-rust interaction. The clarification of the role of the above changes involved in the defence mechanism can significantly contribute to the breeding of plant varieties with natural resistance. Consequently, the amount of chemicals used in food production can be significantly reduced. In the present study some principal physiological parameters, such as the relative chlorophyll content of the host plant, the amount of photosynthetic pigments, changes in photosynthetic efficiency, and the activity of superoxide-dismutase (SOD) in addition to rate of lipid peroxidation (LP) were measured. The experiment was conducted in a humidity tent. Significant decrease in the relative chlorophyll content and in the amount of photosynthetic pigments was measured. At both sampling times, an increase was found in superoxide-dismutase enzyme activity and in rate of lipid peroxidation due to the bean rust infection. Notably, in several cases the differences were significant. The results indicate that the above parameters have important role in the bean-rust interaction, which should be taken into consideration in resistance breeding.
Authors:P. Vilmos, L. Henn, M. Szathmári, T. Lukácsovich, L. Sipos, and M. Erdélyi
The passage of highly specialized germ cells to future generations is essential for the maintenance of species. To date, conventional genetic screens identified relatively few genes that are involved in germ cell development. We aimed to identify germ line specific genes on the X chromosome of
by the application of a new method: the dual-tagging gene-trap system (GT). A modified version of the gene-trap element was used in our experiments and the resulting insertional mutants were screened for grandchild-less phenotype with the help of the attached-X system and a sensitized genetic background developed in our laboratory. Among the 800 insertions mapped to the X chromosome 33 new mutations were identified that exhibited grandchild-less phenotype, 6 gave visible phenotype and 12 were conditional lethal. The cloning of a selected group of the 33 lines showing grandchild-less pheno-type confirmed that we have identified new candidates for genes involved in germ cell development. One of them named
) is discussed in details in this paper. Finally, we also describe a novel automatic selection system developed in our laboratory which enables the extension of the GT mutagenesis to the autosomes.
Authors:L. Danner, N. de Antoni, A. Gere, L. Sipos, S. Kovács, and K. Dürrschmid
This study investigates the relationship between gazing behaviour and choice decision in multialternative forced choice tasks, focusing on the consistency across different food product groups including apple, beer, bread, chocolate, instant soup, salad, sausage, and soft drink. Each choice task consisted of pictures of four alternatives, similar in familiarity and liking ratings, of the corresponding product group. A Tobii T60 eye-tracker was used to present the stimuli and to analyse the gazing behaviour of 59 participants during decision-making.
The results showed strong correlations between choice and gazing behaviour, in forms of more fixation counts, longer total dwell duration, and more dwell counts on the chosen alternative. No correlations for first fixation, time to first fixation, and first fixation duration were observed. These results were consistent across the eight tested product groups.
Authors:Imre Vágó, M. Sipos, L. Tolner, B. Eichler-Löbermann, and I. Czinkota
The effects of genotypes, nutrient and water supply on the dry matter production and potassium uptake dynamics of maize (Zea mays L.) were studied on chernozem soil in the Debrecen-Látókép long-term field experiment (Eastern Hungary).According to the experimental results and calculations it can be concluded that — in addition to the previously used and considered soil and plant nutrient contents — the calculation of the plant-extracted nutrient amount (depending on the applied hybrid, NPK nutrient levels and water supply) is suggested to enable the characterization of the growth and nutrient demand dynamics of maize genotypes. This parameter gives information not only about the available nutrient amount at a given sampling time, but about the supply level of plants up to the sampling time as well. For the proper characterization of the mentioned dynamics of maize plants authors suggest to take the following sampling times into consideration: the intensive vegetative growth period, the switch between the vegetative and generative growth phases (silking), and the grain filling phase.
Authors:V. Losó, A. Tóth, A. Gere, J. Heszberger, G. Székely, Z. Kókai, and L. Sipos
According to international studies the consumer preference of apple varieties is defined by the flavour and texture and the consumers’ opinion about the heavily sour character, the mushy texture and the barely chewable peel is negative. However, the preference level and nutritional values of the apple juices are determined by the variety used, the maturity level and the processing of the fruits. In our study we conducted the external and internal preference mapping of two apple juices with 100% fruit content according to the industrial practice. It propounded several questions about the method of the preference mapping which were the following: product specific training of the assessors, panel performance monitoring, number of samples, representativity, scale use and marking, reasons of the singular matrix, segmentation method, segmentation criterion, power of the paired post-hoc analysis, number of the principal components (PC’s), etc. Finding the answers of the questions above it is possible to establish a good preference mapping practice.