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Alternative to the use of fossil fuels are biofuels (e.g., bioethanol, biodiesel and biogas), which are more environmentally friendly and which can be produced from different renewable resources. In this investigation, bioethanol production from raw sugar beet cossettes (semi-solid substrate) by yeast Saccharomyces cerevisiae in a horizontal rotating tubular bioreactor (HRTB) was studied. Obtained results show that HRTB rotation mode (constant or interval) and rotation speed have considerable impact on the efficiency of bioethanol production in the HRTB. The main goal of this research was to develop a non-structural mathematical model of bioethanol production from raw sugar beet cossettes in the HRTB. The established mathematical model of bioethanol production in the HRTB describes substrate utilization and product formation (glycerol, ethanol and acetate) and presumes negative impact of high substrate concentration on the working microorganism (substrate inhibition) by using Andrews inhibition kinetics. All simulations of bioethanol production in the HRTB were performed by using Berkeley Madonna software, version 8.3.14 (Berkeley Madonna, Berkeley, CA, USA). The established non-structural bioprocess model describes relatively well the bioethanol production from raw sugar beet cossettes in the HRTB.

The underutilized biomass and different organic waste streams are nowadays in the focus of research for renewable energy production due to the effusive use of fossil fuels and greenhouse gas emission. In addition, one of the major environmental problems is also a constant increase of the number of organic waste streams. In a lot of countries, sustainable waste management, including waste prevention and reduction, has become a priority as a means to reduce pollution and greenhouse gas emission. Application of biogas technology is one of the promising methods to provide solutions for both actual energy-related and environmental problems. This review aims to present conventional and novel biogas production systems, as well as purification and upgrading technologies, nowadays applicable on a large scale, with a special focus on the CO2 and H2S removal. It also gives an overview of feedstock and the parameters important for biogas production, together with digestate utilization and application of molecular biology in order to improve the biogas production., Nedovoljno iskorištena biomasa i različiti tokovi organskog otpada su u današnje vrijeme u fokusu istraživanja proizvodnje obnovljive energije, zbog raširene upotrebe fosilnih goriva i emisije stakleničkih plinova. Osim toga, jedan od glavnih ekoloških problema je stalno povećanje broja tokova organskog otpada. U mnogim je zemljama održivo gospodarenje otpadom, uključujući prevenciju i smanjenje otpada, postalo prioritet radi smanjenja onečišćenja okoliša i emisije stakleničkih plinova. Primjena tehnologije proizvodnje bioplina jedna je od obećavajućih metoda traženja rješenja za aktualne energetske i ekološke probleme. Svrha je ovog preglednog rada bila prikazati konvencionalne i nove sustave za proizvodnju bioplina te tehnologije pročišćavanja i obogaćivanja bioplina, koje se danas primjenjuju u velikom mjerilu, s posebnim naglaskom na uklanjanje CO2 i H2S. Ovaj rad također daje pregled sirovina i parametara važnih za proizvodnju bioplina, kao i podataka o korištenju digestata i primjeni molekularne biologije za poboljšanje proizvodnje bioplina.

Agaricus bisporus, also known as the white button mushroom or champignon, is the most cultivated mushroom species worldwide. In addition to its favorable nutrient profile, it contains a number of compounds with antioxidant, antibacterial, anti-inflammatory, antitumor, and immunomodulatory activities. Waste biomass is a secondary product obtained from A. bisporus during the harvesting stage. It is underused, although it could be a cheap source of polysaccharides and antioxidants for use in food and feed production, or a source of nutraceuticals and cosmeceuticals. In this study, waste biomass was used as raw material for extraction of crude polysaccharides. The mean amount of crude polysaccharides extracted was 106 g/kg dry weight debris-free mushroom waste biomass. The crude polysaccharides recovered contained 11.57% α-glucan and 16.37% β-glucan. Total carbohydrates composed 44.18%. No significant differences were found in the Fourier transform infrared spectra, which confirmed the presence of protein, α-glucan, and β-glucan in all samples ; phenols were detected only in waste biomass and market-ready A. bisporus fruiting bodies. The total phenol content in methanol extracts of waste biomass and A. bisporus fruiting bodies was 6.16 and 11.25 mg gallic acid equivalents/g extract, respectively. Antioxidant capacities of methanol extracts from waste biomass, as determined by spectrophotometric techniques, were 22.67 μmol Trolox/g extract (ABTS radical scavenging), 51.77 μmol Fe2+/g extract (ferric- reducing antioxidant power), and 51.52% (DPPH radical scavenging). Although these values were lower than those for A. bisporus fruiting bodies, the waste biomass has great potential for use in food, feed, and other bioproducts of economic importance.

Functional foods are foods that provide positive health effects apart from the provision of essential nutrients. Along with nutraceuticals, they represent the top trends in the food industry. Fruit wines are considered functional foods. When assessing the fruit wine quality, a wide range of descriptors are taken into consideration, namely physicochemical and sensorial properties of fruit wine. Furthermore, within the context of the new food products development (e.g. functional products), functional properties of fruit wines are also taken into consideration. Functional properties are determined by the content of the biologically active components, such as polyphenols, vitamins and micro- and macrominerals. It is also important to consider the food-safety issues regarding the fruit wines consummation, that is, the presence of pesticides, mycotoxins and biogenic amines in different fruit wines. This chapter aims to give an overview of various factors used to evaluate the quality and the functional properties of fruit wines.

Fruit wines production has been growing steadily in recent years, and its market potential is strong, which correlates with the demand for and development of new functional products. Likewise, the production of fruit wines has become an integrated component of fruit processing industry, often compensating for post-harvest losses. Fruit wines represent a value-added fruit product. They contain nutritionally important components like minerals and antioxidants, as well as aromatic nuances typically from the fruits used. The paper gives a general overview of the production of fruit wines with a particular emphasis on the quality of fruit to be used for wine processing, as well as fermentation and post-fermentation processes.

Poljoprivreda, šumarstvo i prehrambena industrija izvori su velike količine lignocelulozne biomase, koja može poslužiti kao lako dostupna i jeftina obnovljiva sirovina za dobivanje različitih bioproizvoda. Jedan od takvih proizvoda je i bioetanol. Ovaj rad daje pregled bakterija koje se koriste i/ili istražuju za proizvodnju bioetanola iz lignoceluloznih sirovina. U navedenim istraživanjima proizvodnje bioetanola pomoću bakterija primijenjuju se različiti pristupi kako bi se povećala ekološka i ekonomska efikasnost procesa. Pored uobičajenih bioprocesa, koji se provode u više faza i uz pomoć monokulture, razvijaju se i visokointegrirani (konsolidirani) bioprocesi uz primjenu mikrobnih kokultura., Agriculture, forestry and food industry are sources of large quantities of lignocellulosic biomass, which can be used as an easily accessible and cheap renewable raw material for production of different bioproducts. One of these bioproducts is also bioethanol. This paper provides an overview of bacteria used and/or investigated for bioethanol production from lignocellulose-containing feedstocks. In the research of bioethanol production using bacteria, various approaches are applied in order to increase ecological and economic efficiency of bioprocess. In addition to conventional multi-stage bioprocesses that are carried out using monoculture, highly integrated (consolidated) bioprocesses and applications of microbial cocultures are also in developing stage.

Solid state cultivation of Ganoderma lucidum biomass, strain BFWS Gal 4, originally isolated from the Slovenian forest, was studied in a horizontal stirred tank reactor. Periodic mixing of N = 80 rpm, 2 min/day was used. Production of fungal polysaccharides and fungal biomass on solid substrate based on beech sawdust, olive oil, and mineral salts was studied. Optimal moisture of the solid matrix was in the range of 80% to 74%. When the moisture content dropped below 57%, the growth of the mycelium and polysaccharide production stopped, but it revived when wet air was applied in further processing. Final concentration of biomass was 0.68 mg/g of solid substrate, while proportions of extracellular and intracellular polysaccharides were 4.5 mg/g and 1.05 mg/g, respectively.

Volatile aroma compounds production by two autochthonous Saccharomyces cerevisiae strains, isolated from Istria region, and three other yeast strains (Saccharomyces bayanus and two commercial Saccharomyces cerevisiae wine yeasts) was investigated on a small scale using synthetic VP4 medium and Graševina must at 12 and 20°C. The results obtained by gas chromatography analyses were compared with the aroma production properties of the native microflora, remaining after Graševina must sulphiting. In both media and at both temperatures, the wine yeasts investigated showed different metabolic profiles regarding the tested volatile aroma compounds, which should be taken in consideration for autochthonous wine production. Although the synthetic medium proved to be appropriate for the investigation of the fermentative properties, the determination of secondary aroma production by wine yeasts has to be conducted by must fermentation or possibly by fermentation of another synthetic medium whose composition would be more similar to must.