One of the garlic processing methods is fermentation, which produces black garlic with completely different chemical, physical, sensory, culinary, and health-enhancing properties. Our study aimed to compare the influence of various processing conditions on the quality indicators of black garlic (BG). Samples of white garlic (WG) were placed in laboratory climatic chambers. BG1 samples were packed in plastic bags and vacuumed, BG2 and BG3 samples were packed in textile mesh bags. BG1 samples were fermented in 70% humidity at 50 °C for 28 days, BG2 samples in 85% humidity at 60 °C for 99 days, and BG3 samples in 80% humidity at 80 °C for 14 days. The dependence of changes in chemical composition, color, and texture of garlic on fermentation conditions was analyzed. Proximate composition analyses and antioxidant activity of WG and BG were performed using standard methods. It was established that regardless of the fermentation conditions, BG’s chemical composition became richer than WG’s. They significantly increased vitamin C content (1.5–5.8 fold), titratable acidity (14.7–21.0 fold), protein (1.4–3.2 fold), fiber (4.6–7.0 fold), and ash (1.2–3.9 fold) content, amount of total phenolic compounds (6.6–9.6 fold) and antioxidant activity (5.3–9.9 fold). Fermented garlic turned dark in color and soft and sticky in texture. The higher fermentation temperature (80 °C) but the shorter time (14 days) had the greatest positive effect on the quality of black garlic.

The rising interest in lowering the use of fossil fuels, which influence environmental pollution and global warming, is driving a substantial increase in renewable sources. Agricultural residues are the likely potential source for bioenergy generation. Some of them are already utilized for energy. Nonetheless, their potential is underutilized due to low biomass quality and high concentrations of sulfur and chloride, which induce the corrosion of adjoining equipment. However, their ash content and ash melting point make their utilization as renewable resources essential. Therefore, there is a need to find technologies to enhance biomass utilization for bioenergy processes. With the increase in hemp cultivation to extract phytocannabinoids, the amount of unused biomass has increased. The aim of this research was to investigate the use of hemp biomass for pellets and improve pellet quality by mixing them with lignin and oak sawdust. The results showed that the lowest amount of ash was found in pellets with 80% oak sawdust and 20% hemp residue compared with pellets made from mixtures of hemp residues, lignin, and oak sawdust. The highest calorific value was achieved by mixing hemp residues (20%) with lignin (80%).

Due to environmental pollution and global warming, the use of renewable energy sources such as agricultural residues is gaining attention. Corn is the main source of food in many countries, and after harvesting it, the agricultural and industrial sectors generate significant amounts of residues. This study focused on corncob processing, its preparation, and the evaluation of its characteristics for energy needs. There was no significant difference between drying with active ventilation in the dryer and outdoor drying conditions. The adequate moisture content of corncob pellets is 12.39% at a compression ratio of 3.43 ± 0.011 and a maximum pellet density of 1012.96 ± 3.35 kg m⁻³. The variation in pellet density at a given adequate moisture content is at least 0.78%. The compression ratio of the pellets compacted on the horizontal matrix granulator is 9.75% higher than that of the pellets produced on the laboratory automatic press. The corncob’s lower calorific value was 17.35 ± 0.14 MJ kg⁻¹, and the ash content was 1.78 ± 0.24%. The produced pellets are strong enough and can be used for combustion. This research may help to better understand the properties of corncobs and their energy potential.

In the world, as in Lithuania, there is a costant search for new crops suitable for energy conversion. The coarse-energy crops and their biomass studied for this paper were assessed in a comprehensive manner, i.e., not only their calorific value and ash content but also their ash melting properties and pollutants emitted during the thermochemical conversion. The calorific value of energy crops varies from 17.92 ± 0.32 to 18.50 ± 0.66 MJ kg⁻¹ and decreases in the following order: A. dubia > M. giganteus > C. sativa. Ash content varies from 1.51 ± 0.03 to 3.36 ± 0.23% and decreases in the following order: C. sativa > A. dubia > M. giganteus. The lowest primary ash deformation (648 ± 8 °C) was recorded for C. sativa. Taking into account the specificity of our research and the changes in biomass ash content due to mineral nitrogen fertilization, it has been found that that higher levels of nitrogen fertilizers in the combustion products reduce CO and increase the total CO₂ content of the combustion product. Significant changes in fertilization were usually 170 kg ha⁻¹ for A. dubia and 90 kg ha⁻¹ for M. giganteus. In summary, A. dubia, M. giganteus and C. sativa biomass should be used for thermochemical conversion.