The aim of our experiments was to demonstrate the non-thermal effect of microwave treatment on Saccharomyces cerevisiae fermentation activity. A method was developed for studying the effects of various treatments in the course of must fermentation. The raw material (must) was treated in different ways: (i) heat transfer; (ii) microwave treatment; (iii) inoculation with yeast, and (iv) their combinations. The results of the treatments were compared with respect to alcohol concentration, sugar content, and acidity. The results proved that sugar content of the treated samples rapidly decreased compared to the control sample, and fermentation time was 40% shorter in the fastest case. These results can be explained by the yeast inoculation and microwave treatment. Due to non-thermal effects, fermentation capacity increased by about 30%, while the energy consumption decreased.
BeszÉDes, S. (2014): Szennyvíziszapok biológiai lebonthatóságának növelése mikrohullámú előkezeléssel. (Improvement of biodegradability of sludge by microwave pre-treatment). PhD thesis, University of Szeged, 129 pages.
BeszÉDes, S., LÁSzlÓ, Zs., HorvÁTh, H-Zs., SzabÓ, G. & HodÚR, C. (2011): Comparison of the effects of microwave irradiation with different intensities on the biodegradability of sludge from the dairy- and meat-industry. Bioresource Technol., 102(2), 814–.
Biacs, P., SzabÓ, G., SzendrŐ, P. & VÉHa, A. (2010): Élelmiszer-technológia mérnököknek (Food-Technology for Engineers), SZTE Mérnöki Kar, Szeged, pp. 345–385.
Calado, C.R.C., Taipa, M.A., Cabral, J.M.S. & Fonseca, L.P. (2002): Optimisation of culture conditions and characterization of cutinose produced by recombinant Saccharomyces cerevisiae. Enzyme Microb. Tech., 31, 161–170.
Dreyfuss, M.S. & Chipley, J.R. (1980): Comparison of effects of sublethal microwave radiation and conventional heating on the metabolic activity of Staphylococcus aureus. Appl. Environ. Microb., 39(1), 13–.
Eperjesi, I., KÁLlay, M. & Magyar, I. (1998): Borászat (Winery). Mezőgazda Kiadó, Budapest, 547 pages.
Farkas, G., Rezessy-SzabÓ, J.M., ZÁKÁNy, F. & Hoschke, Á. (2005): Interaction of Saccharomyces and non- Saccharomyces yeast strains in an alcoholic fermentation process. Acta Alimentaria, 34, 81–90.
GÉCzi, G., Korzenszky, P., HorvÁTh, M. & MolnÁR, E. (2013): Heat treatments versus fermentation. Animal Welfare, Ethology and Housing Systems, 9(3), 448–.
Golant, M.B., Kuznetsov, A.P. & Bozhanova, T.P. (1994): The mechanism of synchronizing yeast cell cultures with EHF radiation (in Russian), Biofizika, 39, 490–495.
Grundler, W., Keilman, F. & Froehlich, H. (1977): Resonance growth rate response of yeast cells irradiated by weak microwaves. Physics Lett. A., 62, 463–466.
Grundler, W., Keilman, F., Putterlik, V. & Strube, D. (1982): Resonant-like dependence of yeast growth rate on microwave frequencies. Brit. J. Cancer, 45, 206–208.
Grundler, W., Jentzsch, U., Keilman, F. & Putterlik, V. (1988): Resonance cellular effects of low intensity microwave. - in: Frolich, H. (Ed.), Biological coherence and response to external stimuli. Springer-Verlag, Berlin, pp. 65–85.
HUNGARIAN STANDARD (1982): Borok szesztartalmának meghatározása Malligand-készülékkel (Determination of alcohol content of wines with Malligand-device). MSZ 9457:1982.
KÁLlay, M. (2010): Borászati kémia. (Oenological chemistry). Mezőgazda Kiadó, Budapest, 206 pages.
Korzenszky, P. & MolnÁR, E. (2014): Must tartósításának vizsgálata (Examination of preservation of grape must). Konzervújság, LXII.(1), 27–31.
Korzenszky, P. & MolnÁR, E. (2014): Examination of heat treatments at preservation of grape must. Potravinarstvo, 8(1), 33–.
Kothari, V., Patadia, M. & Trivedi N. (2011): Microwave sterilized media supports better microbial growth than autoclaved media. Res. Biotechnology. 2(5), 63–.
Novales, J-F., LÓPez, M-I., SÁNchez, M-T. & Morales, J. (2009): Shortwave-near infrared spectroscopy for determination of reducing sugar content during grape ripening, winemaking, and aging of white and red wines. Food Res. Int., 42, 285–291.
OIV (2009): Total acidity, revised by 377/2009, OIV-MA-AS313-01
Pickering, G.J., Heatherbell, D.A. & Barnes, M.F. (1998): Optimising glucose conversion in the production of reduced alcohol wine using glucose oxidase. Food Res. Int., 31, 685–692.
Pretorius, I.S. (2000): Tailoring wine yeast for the next millennium: Novel approaches to the ancient art of winemaking. Yeast, 16, 675–729.
Rai, S., Singh, U.P., Mishra, G.D., Singh, S.P. & Samarketu, S.P. (1994): Effect of water’s microwave power density memory on fungal spore germination. Electro Magnetobiol. 13, 247–252.
Rai, S., Singh, U.P., Mishra, G.D., Singh, S.P. & Samarketu, S.P. (1994): Additional evidence of stable EMFinduced changes in water revealed by fungal spore germination. Electro Magnetobiol. 13, 253–259.
Sablayrolles, J.M. (2009): Control of alcoholic fermentation in wine making: Current situation and prospect. Food Res. Int., 42, 418–424.
Shu-Wei, Z., Qi-Lin, H. & Si-Ming, Z. (2014): Effects of microwave irradiation dose and time on yeast ZSM-001 growth and cell membrane permeability. Food Control, 46, 360–367.
ThÉNard, L.J. (1875): Rapport sur un appareil de M. Malligand, pour titrer l’alcool des vins. Compt. rend., 80, 1114.
Trivedi, N., Patadia, M. & Kothari, V. (2011): Biological applications of microwaves. Int. J. Life Sci. Tech., 4(6), 37–.
Wayland, J.R., Brannen, J.P. & Morris, M.E. (1977): On the interdependence of thermal and electromagnetic effects in the response of Bacillus subtilis spores to microwave exposure. Radiat. Res., 71, 251–258.
Welt, B., Tong, C., Rossen, J. & Lund, D. (1994): Effect of microwave radiation on inactivation of Clostridium sporogenes (PA 3679) spores. Appl. Environ. Microb., 60, 482–488.