Browsing by Subject "descriptor"

This Master's thesis compares the commercial cooking tests of potatoes in Finland and Europe. The cooking type comprises the structural properties of potato, which are described e.g. in terms of floury and waxy or types A-D. Other measures of cooking quality, such as color, taste and odor, were excluded from the work. The main focus of the thesis was on the survey of European cooking type tests and on the comparative study of descriptors for different varieties. As the use of descriptors and terminology differ slightly from one country to another, the significance of the differences in the resulting cooking type result was also considered. In the study, seven varieties with seven different meters and a total of 12 different measuring methods were compared. The key method of the thesis was sensory evaluation by descriptive method. The descriptors were used as unambiguously as possible, such as evaluating flouriness by appearance and by palpation in the mouth. In addition to sensory evaluations, experiments with structure analysis, hyperspectral imaging, and color measurement were included in the study. The purpose of the analysis was to look at the descriptor ensembles, and to observe their dimension on the axis waxy - floury and possible other independent dimensions that would diversify the description of the cooking quality. The results were examined statistically by means of generalized linear models, correlations and principal component analysis. The thesis concluded that there are some differences between European ways of determining the cooking type, and in borderline cases, different results are possible. In general, European descriptor ensembles are strongly built to support the waxy-floury axis. In addition to the descriptor ensembles, the cooking type determination include procedures and calculation methods and cannot be separated from the whole. The results of the study support the fact that hardness/softness is an independent dimension, and hardness determined by the texture analyzer clearly distinguished the varieties. In sensory comparison, external observation and mouthfeel evaluation produced similar results, except for hardness assessment. The instrumental methods distinguished the varieties more clearly than sensory evaluation. Disintegration analyzed by color measurement and starch content is a viable combination for cooking type determination.