Studies on the synthesis of esters of natural origin fatty acids (oleic acid) and a branched synthetic isostearic acid derived from oleic acid with commercially available selected higher polyols in the presence of homogeneous metallic catalysts have been carried out. The effects of the synthesis temperature, molar ratio and the catalysts amount have also been studied. It was shown that higher fatty acid conversion and selectivity to tri- and tetraesters were obtained for organotin catalyst Fascat 2003, which was used as the esterification catalyst. Anti-wear test confirmed good tribological properties of the obtained esters.

In this paper, we present the study on the synthesis, physico‐chemical, and tribological characterisation of selected plant‐derived fatty acids esters of higher polyols. We described here more effective method synthesis of desired esters with high yields and high selectivities. In our novel and improved synthesis protocol, we applied homogeneous Sn catalysts. Physico‐chemical characterisation and lubricating properties of synthesised esters have been determined and discussed. Our results showed that the synthesised esters are characterised by excellent viscosity, good low temperature, and lubrication properties. High thermal resistance is the main benefit of synthesised esters. For fatty acid esters of trimethylolpropane dimer, onset temperatures are around 400°C and decomposition temperatures above 460°C, which makes these esters applicable in higher temperature.

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A class of very important industrial-grade biolubricants was synthesized from plant-derived fatty acids (oleic and isostearic acid) by direct esterification of trimethylolpropane according to novel effective and high selective method using Sn bis(2-ethylhexanoate) as catalyst. Model transesterification reactions were performed with oleic and isostearic acids to optimize the reaction conditions to obtain maximum content of TMP triesters. Used specific homogeneous Sn catalyst allows to obtain TMP esters with very high content of triesters, above of 94 wt% without deep vacuum purifying distillation. Both TMP esters were evaluated for their physicochemical and tribological properties using ASTM standards. Both TMP esters exhibited high viscosity indexes and excellent low temperature properties.

The paper attempts to determine the best storage conditions for green and roasted coffee beans. Coffee beans were processed in various ways—some of them were washed or left in their natural state after harvesting, then they were stored in two types of packaging with different permeability, i.e. jute bag and GrainPro polymer bag, ensuring stable conditions in three temperature chambers, i.e. − 10, 10 and 20 °C. The grains treated in this way were evaluated after 3, 6, 9, and 12 months. The selection of the analyzed parameters (in roasted coffee—cupping and 3 selected volatile organic compounds; in green coffee—average water activity, content of volatile fatty acids, 6 selected volatile organic compounds) was to monitor the ongoing processes, and thus the qualitative changes taking place in grains. The research shows that grain stored at 20 °C ages the fastest. Grains stored in − 10 °C and 10 °C chambers perform similarly well. The evaluation of the parameters shows that among the grains stored in these two chambers, the method of grain processing (Natural/Washed) had a greater impact on the results, while the type of packaging did not differentiate the grains to such a significant extent.