Technology for Production of Fluoride Enriched Beer

Journal of the UniversityG. Yonkova, of Chemical A. Surleva, Technology T. Ginova-Stoyanova and Metallurgy, 47, 1, 2012, 53-58

TECHNOLOGY FOR PRODUCTION OF FLUORIDE ENRICHED BEER

G. Yonkova, A. Surleva, T. Ginova-Stoyanova

University of Chemical Technology and Metallurgy, Received 15 September 2011 8 “Kl. Ohridski” blvd, 1756 Sofia, Bulgaria Accepted 20 January 2012 E-mail: [email protected]

ABSTRACT

The production of protective foods has gained mush research attention recently due to their ability to reduce the level of radio contamination of human organism. Usually protective foods are widely used foods or drinks specifically designed to have decontaminative properties. The present work proposes a technology for production of fluoride enriched beer with radio protective properties. Naturally fluorinated mineral water was used as a source of fluoride. A mixture of fluorinated mineral and tap water in ratio 1:1 was used and pH adjustment with citric acid was applied during the mashing-in process. Fermentation of the fluoride enriched wort normally occurred. A 17 % decrease of fluoride content during the brewing process was observed. The fluoride enriched beer produced by the proposed technology met the physicochemical and sensory standards. Keywords: fluoride, wort, beer, decorporation, radio protection.

INTRODUCTION 3) altered products obtained by replacing the exciting components with beneficial components; 4) Enhancing natural radio resistance of human or- enhanced commodities changes in the raw commodi- ganism by food has gained much researchers attention ties that altered the nutrient composition. in the functional food industry [1]. Functional food is a The term protective food or drink stands for natural or processed food or beverage that contains known a functional dietary product reducing the level of ra- biologically active compounds which when in defined dio contamination in two ways [4,5]: quantitative and qualitative amounts provides a clinically a) decorporation cleaning of the body of ra- proven and documented health benefit [2]. Different types dionuclide contaminants; of functional food have been defined [3]: b) hindering the radionuclide contaminant ad- 1) fortified products obtained by increasing sorption. Usually it is produced by fortifying a widely the content of exciting nutrients; used food by an appropriate decorporative agent. The 2) enriched products obtained by adding new radioprotective agents minimise or prevent the dam- nutrients or components not normally found in a par- age from radiation exposure caused by nuclear power ticular food; facility, food radiation or other devices that releases

53 Journal of the University of Chemical Technology and Metallurgy, 47, 1, 2012 radiation [6,7]. Protective food and drinks are effec- tive radio prophylaxis means due to the possibility for application to large groups of people for extended pe- riods of time. The annual consummation of beer in Bulgaria is around 70 litres per person and the drink is considered as the most consumed [8]. Moreover, it is known that the beer enhances the excretion function of kidneys and thus intensifies the elimination of toxins from the body. Hence, beer could be used in the radionuclide prophylaxis if an appropriate agent could be found. Fluoride is well recognised as an essential micro- nutrient which participates in tooth and bone building. Fig. 2. Number of suspended cells in the control (n) and the Humans obtain fluoride mainly from their diet. All of the experimental (l) worts. fluoride available in water reaches the blood cycle. In con- trast, between 50 - 80 % of food fluoride is absorbed by human organism [9]. Furthermore, it was proved that fluoride lowers the bodys radioactive contamination and thus acts as a radionuclide decorporation agent espe- cially for cerium and strontium [10-12]. It was estab- lished that the decorporation activity of fluoride is higher if naturally fluorinated waters are used. The content of fluoride in mineral waters is between 5 and 25 mg dm- 3. Usually water is considered as mineral when it contains various soluble substances at high concentrations and its temperature in the spring is above 20oC [13,14]. Due to the biological activity of the micronutri- ent and the drink, fluoride containing beer can be ex- Fig. 3. Apparent extract of the control (n ) and the pected to have a radio protective activity. As water is a experimental (l) worts. basic beer ingredient, it was supposed that a higher effect can be achieved if the fluoride containing mineral water was used in brewing. As we reported previously, mineral water spoiled the quality of the obtained wort and the mashing technology had to be modified [15]. The present study is aimed at developing a technology for production of fluoride enriched beer with potential radio protective properties. As water influences the quality of the produced beer, the characteristics of the products have been carefully examined in every stage of the brewing process.

EXPERIMENTAL

Fluoride containing mineral water from the Fig. 1. pH decrease during the fermentation of the control Blagoevgrad region was used. Composition of used n l wort ( ) and the experimental wort ( ) obtained using tap mineral and tap water is presented in Table 1. A mix- and mineral water in ratio 1:1

54 G. Yonkova, A. Surleva, T. Ginova-Stoyanova

Fig. 4. Fluoride concentration at different stages of the brewing process. ture of mineral and tap water in ratio 1:1 was used. Yeast strain Saccharomyces carlsbergensis was The mashing-in pH adjusted by citric acid was 5.4. used in the fermentation at temperature 9oC. Yeast propa- Wort was produced from malt with 5.3 % of gation was 15 - 20x106 cells cm-3. Beer maturation took moisture; 78.7 % of grist extract; 12.6 % proteins and place at 4oC. Apparent extract, temperature, concentra- 142 mg dm-3 α-amine nitrogen. The saccharizification tion of suspended yeast cells and active acidity of the time was 10 - 15 min, colour was 3.5 EBC and viscosity wort were controlled daily during the fermentation pro- 1.64 mPa s. cess. A single-step mash decoction method was used. Standard analytical methods for beer quality as- Sparing water was at the same composition as in the sessment were used according to the European Brew- mashing. The wort was produced by boiling with á-bitter ing Convention [16]. The fluoride concentration was acids containing hop products (90 mg dm-3). 70 % of hops determined at every stage of the brewing. A protocol were added 15 minutes, and 30 % of hops were added 45 for ion-selective potentiometric determination of fluo- minutes, after the start of the boiling process. The over- ride in mineral water, wort and beer has been devel- all procedure continued 105 minutes. oped [17]. Sample was acidified with HCl before analy-

Table 1. Chemical composition of the used water.

parameter tap water mineral water pH 6.7 8.5 calcium hardness, oH 1.0 0.1 magnesium hardness, oH 1.4 0.2 carbonate hardness, oH 2.6 13.0 residual alkali 2.2 12.9 Ca2+, mg dm-3 14.4 2.0 Mg2+, mg dm-3 3.9 1.6 F-, mg dm-3 0.3 11.5

55 Journal of the University of Chemical Technology and Metallurgy, 47, 1, 2012

Table 2. Physicochemical characteristics of the control wort and the fluoride enriched wort. parameter control worth experimental worth pH 5.25 5.58 colour, EBC 8.0 8.5 viscosity, mPa s 1.72 1.71

α -amine nitrogen, mg dm-3 157 136 final degree of fermentation, % 78.0 79.1 bitterness, BU dm-3 24.6 25.8 fluoride concentration, mg dm-3 0.11 5.0

Table 3. Characteristics of the fluoride enriched beer. parameter control beer fluoride enriched beer alcohol, % 2.84 2.96 apparent degree of fermentation, % 76.7 79.1 final degree of fermentation, % 78.0 79.1 colour, EBC 5.5 5.5 pH 4.1 4.4 bitterness, BU dm-3 16.2 17.0 fluoride concentration, mg dm-3 0.11 4.75

sis to dissolve any formed CaF . 15 ml of filtered and the wort, influencing the pH of the mash and the wort. 2 acidified sample was thoroughly mixed with 15 ml of The higher alkalinity of the mash hindered the activity mixture of 0.25 M Na Cit and 1 M NaCl. Natrium cit- of the enzymes and affected negatively starch hydroly- 3 rate was used as a masking and buffering agent and NaCl sis. The incomplete starch degradation lowered the fi- as an ionic strength adjustor. Potential of the potentio- nal degree of fermentation. Moreover, higher pH of the metric cell (fluoride selective and silver/silver chloride mash, of the sweet wort and of the sparing waters en- reference electrodes) was measured before and after stan- hance the extraction of some undesirable substances such dard addition of NaF. Method accuracy and precision as polyphenols from malt flakes, thus spoiling the qual- were 4% and 1,7 %, respectively. ity of wort and beer. We tested some technological so- lutions: (1) a mixture of tap and mineral water in ratio RESULTS AND DISCUSSION 1:1 was used and (2) pH and hardness adjustment was applied adding citric acid during mashing-in. The fluo- Mashing and wort production ride content of the mineral water was lowered after di- Our previous study had shown that higher re- lution with tap water, thus achieving the health levels sidual alkali and carbonate hardness of the mineral water recommended by authorities [18]. Additionally, a de- from the region of Blagoevgrad had a negative effect on crease of the fluoride content during the mashing pro-

56 G. Yonkova, A. Surleva, T. Ginova-Stoyanova

cess was observed. The final concentration of fluoride was 17 %. The final fluoride concentration in beer was in the cold wort was 5 mg dm-3. Table 2 presents the 4.75 mg dm-3 and completely met the requirements of physicochemical characteristics of the control wort, and European and national regulations [18]. the experimental wort obtained using mixture of tap The characteristics of produced beer are pre- and naturally fluorinated mineral water in ratio 1:1 at sented in Table 3. As can be seen from the results there pH of mash 5.4, adjusted with citric acid. As the results was not a significant differences between the fluoride show the wort obtained using the proposed technology enriched and the control beer, except for the fluoride has the same characteristics as the control wort. concentrations. The fluoride enriched beer produced using mineral water had balanced aroma and specified Fermentation and beer production flavour, bright colour and pleasant hop bitterness. The active acidity, the propagation of yeast, the fermentation rate and the cells settlement of the control CONCLUSIONS and the experimental wort were studied to evaluate the effect of mineral water on the fermentation process. A new technology for production of fluoride en- The changes in pH during fermentation of the riched beer using mineral water is proposed. Tap and experimental wort are presented in Fig. 1. Despite the mineral water in ratio 1:1 was used in the brewing. A pH adjusting of the acidity of the mash by citric acid, a slight adjustment by citric acid was applied during the mashing- difference in the initial pH of the experimental and the in process. No discrepancies in the fermentation process control samples has been observed. During the first three were observed. The final content of fluoride in the beer days of fermentation pH was decreasing sharply as a result meets the requirements of the Bulgarian regulation. The of chemical changes in the buffering system [19]. After produced beer has good taste and aroma. the fourth day the acidity was almost unchanged. The final pH of the experimental and the control samples Acknowledgements were 4.68 and 4.45, respectively. The authors wish to gratefully acknowledge the The number of the suspended yeast cells and the University of Chemical Technology and Metallurgy, Sofia, apparent extract of the experimental fluoride enriched Bulgaria, for the financial support of this research by Grant wort, and the control wort are presented in Figs. 2 and 3, 10750/2010 from the Science and Research Program. respectively. The extracts content in the control sample decreased to 2,7 % till the end of the sixth day, but in REFERENCES the experimental wort the same value was obtained after 7 days of fermentation. During the wort fermenta- 1. P. Jones, S. Jew, Functional food development: con- tion maximum cell growth was reached during the sec- cept to reality, Trend Food Sci. Techn., 2007, 387- ond day. The final yeast cells concentrations in the ex- 390. perimental and the control young beers were equal. 2. D. Martirosyan, (ed.), Functional foods and Chronic The characteristics of the experimental and the diseases, Science and Practice, Food Science Publ., control samples coincide well showing that the 2001. fermentation of fluoride enriched wort had normally 3. J. Spence, Challenges related to the composition of occurred. functional food, J. Food Comp. Anal., 19, 2006, S4- S6. Characteristics of the fluoride enriched beer 4. D. Maurya, T. Devasagayem, G. Ivair, Some novel The fluoride content was studied during the over- approaches for radioprotection and beneficial effect all brewing process. The results are presented in Fig. 4. of natural products, Ind. J. Exp. Biology, 44, 2006, A slight decrease in the fluoride content during the 93-114. mashing process was observed (down to 5 mg dm-3). 5. D. Taylor, G. Stradling, M. Henge-Napli, The scien- The next brewing procedures did not affect consider- tific background to decorporation, Radiat. Prot. ably the fluoride concentration. The overall decrease Dosim., 87, 2000,11-17.

57 Journal of the University of Chemical Technology and Metallurgy, 47, 1, 2012

6. N. Prasad, M. Srinivasan, K. Pagalenti, P. Venugopal, 12. Z. Paskalev, Decorporation effect of natural fluo- V. Menon, Protective effect of feluric acid on gamma- rine mineral waters in Bulgaria on some osteotropic radiation-induced micronuclei, dicentic aberration radionuclides, Rentgenol. Radiol., 21, 1982, 22-26. and lipid peroxidation in human lymphocytes, Mu- 13. BG Regulation 6 of 3 August 2004 on the Require- tation research, 603, 2006, 129-134. ments to bottled, natural, mineral, spring and table 7. A. Dixit, D. Bhatnagar, V. Kumar, D. Chawla, K. waters intended for human consumption, Bulgarian Fuhruddin, D. Bhatnagar, Antioxidant potential and State Gazette Nr 68 of 3 august 2004 and Bulgarian radioprotective effect of soy isoflavone against gamma State Gazette Nr 66 of 25 July 2008. irradiation induced oxidative stress, J. Functional 14. BDS 14947-80, Bulgarian natural mineral waters Foods, 2011, doi: xd.doi.org/10.1016/j.jff.2011.10.005. 15. G. Yonkova, V. Zhivkova, A. Surleva, Use of fluo- 8. www.pivovari.com ride containing mineral water in wort production, 9. L. Ivanova, Biological impact, prophylactic effect and St. Cerc. St. CICBIA, 12, 2011, 373-380. toxicity of flour, Lechitel, 2008, (in Bulgarian). 16. European Brewery Convention, www.european 10. Z. Paskalev, G. Kalajdziev, G. Kabakchieva, Using breweryconventions.org. some foods and drinks for radioprotection purposes, 17. L. Ilcheva, G. Kabakchieva, P. Bozadjiev, Z. Denchev, IInd Scientific Conference Medicine of disasters, Conventional and flow techniques for fluoride deter- 20-22 October, 1993, Sofia, Bulgaria, (in Bulgarian). mination in bioproducts, III National Conference of 11. L. Dyankov, G. Kalajdzhiev, Z. Paskalev, Dynamic Chemistry, 1998, Plovdiv, Bulgaria, (in Bulgarian). examination of callus and of 85-strontium kinetics 18. BG Regulation 23 about physiological standards in in the lower leg bones of rats with traumatic injuries nutrition, 2005. treated with fluorine mineral waters, Rentgenol. 19. I. Kapzev, Technology of beer and alcohol free bev- Radiol, 22, 1983, 55-59. erages, Zemizdat, Sofia, 1993, p. 146 (in Bulgarian).