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Increasing demands of the present society lead to an effort to rationalize logging operations in forest management. Therefore, multi-function logging machines are increasingly used in the course of timber harvesting. Nevertheless, the economic effectiveness of these machines is affected not only by their productivity or environmentally friendly operations but also the quality of performed work. It can be evaluated by the assessment of the quality of produced assortments. Decreasing quality of produced logs can result in the reduction of marketability and wood price. Thus, the aim of this paper is to determine some defects originating at the harvester production of assortments and specification of their potential causes.

The aim of this thesis was to evaluate the changes of the microbiological quality of milk during storage. Fresh pasteurized milk was used for the laboratory experimentations. Cooling chain of the samples was broken for 8 and for 12 hours at different temperatures (22-30 °C). In these samples, total count of psychrotrophic microorganisms was assessed.
Technological indiscipline, i. e. higher storage temperature (24 °C and more), was associated with higher increase of total count of microorganisms and psychrotrophic microorganisms. Microbiological results proved that the samples stored under standard conditions were of very good quality. However, in fresh pasteurized milk the representation of total count of microorganisms and psychrotrophic microorganisms meets fully the norm requirements. It is necessary respect a sustentation of a lower temperature of fresh pasteurized milk during storage, especially in summer months.

There is a need for fast, cheap and sufficient accurate methods for prediction of barley grain quality. The determination of Brabender hardness seems to be promising. The aim of this work was to compare three different methods for evaluation of graphic output from Brabender farinograph and subsequently select the most optimal method for routine laboratory work. 108 samples (twelve cultivars from three localities and three years) were analyzed for grain hardness. Simultaneously selected parameters of grain and malt were determined. The correlations among methods for evaluation were estimated as well as among selected technological traits of barley grain and malt.
Grain hardness expressed by area under curve (counted by specific weight of paper 'A' and measured by planimetr 'B') showed tendencies to distinguish the varieties by their malting quality. The same trend was not observed for the method C (hardness expressed by maximum value of peak). Nearly perfect positive correlation (0.99***) was found between the results of method A and method B. Medium correlation was found between values obtained by method A and method C (0.58***).
Significant correlations were established between values obtained by method A and extract (-0.63***), mash method according to Hartong and Kretschmer (-0.61***), the Kolbach index (-0.70***), friability (-0.71***), β-glucans in wort (0.76***), partly unmodified grains (0.71***), and non-starch polysaccharides content (in total β-glucans and pentosans) (0.67***).
Hardness values obtained by method C were related to partly unmodified grains (0.52**), β-glucans in grain (0.61**), and non-starch polysaccharides content (in total β-glucans and pentosans) (0.56**).
The most appropriate evaluation method was selected on the base of results of Tukey test as well as the level of correlation among the hardness level and selected quality parameters.

This paper is focused on validation of new synthetic raw cow milk quality indicator which was calculated according to previously developed algorithm. The aim was to carry out a synthesis of values of individual milk quality indicators (MQIs) into one standardized relative milk quality indicator (SQSM). This is useable for farmer milk price modification according to milk quality in dependence on its change in every case. It is a possible ground for consistent milk payment according to its quality. This work is fifth step in the row of works. It is carried out in terms of next promotion of the milk foodstuff chain safety and for the improvement of the ability of the dairy production branch for the competition. SQSM was calculated according to formula as follows: DX = (IND - x)/sx, where: IND is individual value of MQI of supplier, x is month arithmetical average of MQI of relevant milk suppliers including IND and sx its standard deviation; SQSM is the sum of logically oriented (according to milk quality growth) DXs, which come from relevant MQIs of identical raw milk delivery; SQSM as sum can be also divided by the number of MQIs. It means, there are possible two kinds of expressions of SQSM, sum (a) and/or average (p). The values of MQIs were used in original (compositional and physical MQIs) or transformed (log; hygienic MQIs) form according to previous research results. Three, five and seven MQIs and single, double and threefold values of their technological weight were included into model validation as price formula. Thirteen variants (p and a) of price formula were used, too. The behaviour of p and a model variants was similar. All SQSM averages and medians were very near zero value. The normality of SQSM files was reached (P > 0.05) sometimes in obliquenes (a₃) which is more important in this case. The normality was not reached in acuteness (a₄). The SQSM model files were quite well balanced in terms of positive and negative values. All model combination differences (p) between variants were insignificant (calculated F 1.76×10^-18, where P > 0.999; critical F 1.75 for P ≤ 0.05). The difference insignificance was independent both on number of MQIs and on their technological preference as well. The results of SQSM validation showed the suitability of indicator usage for intended purpose of consistent milk price modification according to every milk quality change.

Effect of breed (German Long-wooled breed, GL, n = 6) and different crossbreeds of lambs males of breeds GL, Merino (M) and Oxford Down (OD) on meat quality was evaluated on the basis of laboratory analyses of muscle of right rack (musculus triceps brachii). Following crossbreeds of lambs were evaluated: OD 50 M 25 GL (n = 6), GL 50 OD (n = 6), OD 75 GL (n = 6) and GL 75 OD (n = 6). Breed and crossbreeds had a highly significant effect (P ≤ 0.01) on contents of intramuscular fat (IMF) and ash. The factor of breed and crossbreeds had also a highly significant effect (P ≤ 0.01) on water holding capacity and reflectance and a significant effect (P ≤ 0.05) on pH of meat in the period of 24 hours after slaughter (pH 24). On the other hand the factor of breed and different crossbreeds had not significant effect on contents of dry matter (DM), protein (P), myoglobin, hydroxyproline, collagen, elastin and connective tissue. This factor had not also significant effect on energy value in the original matter. The highest values of DM (23.60 %) and IMF (3.56 %) were found in OD 50 M 25 GL. The highest values of ash (1.05 %) were foud in GL 100 and OD 75 GL. The highest value of connective tissue (2.23 mg in 100 g of muscle) was found in OD 50 M 25 GL. On the other hand its lowest content (1.86 mg in 100 g of muscle) was found in OD 75 GL.