Antimicrobial Effectiveness of Potassium Sorbate and Sodium Benzoate Against Zygosaccharomyces Bailii In

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Journal of Food Protection, Vol. 58, No. 11, Pages 1257-1259 Copyrighl©, International Association 01 Milk, Food and Environmental Sanitarians

A Research Note

Antimicrobial Effectiveness of Potassium Sorbate and Sodium Benzoate against Zygosaccharomyces bailii in

a Salsa Mayonnaise Downloaded from http://meridian.allenpress.com/jfp/article-pdf/58/11/1257/1659760/0362-028x-58_11_1257.pdf by guest on 24 September 2021

CHARLES E. WINDI* and LAWRENCE RESTAIN02

'Mullins Food Products, 2200 South 25th Avenue, Broadview, IL 60515; and 2R & F Laboratories, 7510 W. 99th Place, Bridgeview, IL 60455

(MS# 94-279: Received 8 December] 994/ Accepted 8 May] 995)

ABSTRACT 14). The activity ofthese preservatives increases as the pH of the product decreases due to the formation of undissociated The antimicrobial effectiveness of sodium benzoate and potassium sorbate (0.05, 0.10,0.20 and 0.30%, wt/wt), separately and in acid (14). The optimal pH ranges for these preservatives are equal combinations, were evaluated against the growth of 2.5 to 4.0 for sodium benzoate (2) and 6.5 or less for potassium Zygosaccharomyces bailii in an artificially inoculated salsa mayon- sorbate (2, 14). naise stored at room temperature (23 to 25°C). Potassium sorbate The purpose of this study was to determine the effects of was able to suppress the growth of Z. bailii significantly (P < 0.05) sodium benzoate and potassium sorbate at various concentra- more than sodium benzoate did, whereas no significant difference in tions against the growth of Z. baWi artificially inoculated into growth was calculated between potassium sorb ate and the combina- a salsa mayonnaise product. tion in equal amounts of the two preservatives. Equal concentrations of the two preservati ves were, however, significantly (P 0.05) more < MATERIALS AND METHODS effective than sodium benzoate in suppressing the growth of the yeast in a salsa mayonnaise. At the investigated concentrations, the preser- Preparation of salsa mayonnaise vative systems did not prevent spoilage of the product by Z. bai/ii. The formulation of salsa mayonnaise consisted of 10,528.64 g Therefore, the use of yeast-free ingredients, clean and sanitary of soybean oil, 4,07 1.89 g of water, 934.09 g of egg yolks (containing equipment, and strict adherence to good manufacturing practices 10% wt/wt, NaCl), 707.32 g of vinegar (120 grain), 489.72 g of during manufacture and packaging is required to produce a salsa brinedjalapeno peppers, 353.68 g of high fructose com syrup, 335.55 mayonnaise free of spoilage microorganisms. g of tomato paste, 163.24 g of salt, 95.22 g of mustard. flour, 68.02 g of cumin, 54.41 g xanthan gum, 27.21 g cilantro, 13.60 g of garlic powder, 9.07 g of onion powder, 9.07 g of dehydrated onions, 1.36 Key words: Zygosaccharomyces bai/ii, preservative, mayonnaise g of jalapeno powder, 0.75 g. of calcium disodium ethylene- diaminetetraacetate, and 0.27 gof citric acid. All ingredients except New products such as salsa mayonnaise, created by the egg yolks and oil were mixed and cooked to 100°C in a laboratory adding spicy salsa sauce to traditional condiments, have scale steam-jacketed kettle. After the mixture cooled, the egg yolks become popular in the United States. Salsa mayonnaise is a and soybean oil were added to form the emulsion, using a Scott Turbon mixer. The product was packaged in a 5-gal polypropylene blend of mayonnaise and Mexican-style salsa sauce, which is pail (sanitized priorlo use) and refrigerated until use. Aliquots of250 a tomato-based product containing onions, chile peppers, g of salsa mayonnaise were aseptically added to sterile stomacher vinegar, and piquant spice (4, 7). bags (400-ml capacity; Tekmar). Various levels of sodium benzoate Spoilage of mayonnaise can occur when it is mixed with and potassium sorbate (wt/wt) were added to the stomacher bags and brined products such as relish, chile sauce, olives, or pimentos blended by the stomacher (Seward Medical) for 4 min at high speed (1, 5). Mayonnaise can be spoiled by yeasts (5), molds (12), to completely dissolve the preservative in the mayonnaise. The final and lactic acid bacteria (12), with the osmotolerant yeast preservative concentrations separately and in equal amounts were 0.05, OJ, 0.2, and 0.3%. The chemical characteristics of the salsa Zygosaccharomyces haifii being the most common spoilage mayonnaise were pH 3.74, acid (as acetic acid) 0.46%, salt (as NaCI) organism (4, 8-10,12,14-16). Spoilage is characterized by 1.51%, fat 66.50%, and moisture 28.10%; the water activity was the production of gas, slight separation of product, and off or 0.949 (21.6°C). "yeasty" odor (5,7,9,12,14). Sodium benzoate and potassium sorbate are commonly Yeast strain culture and growth used alone or in combination to control the growth of yeasts, Z. bailii (isolated from mayonnaise) was obtainedJrom Si11iker molds and bacteria in mayonnaise-based products (2,10, 12, Laboratories, Chicago Heights, fL. The culture was maintained on

JOURNAl, OF FOOD PROTECTION. VOL. 58, NOVEMBER 1995 1258 WIND AND RESTAINO

Difco Laboratories (Detroit, MI) Sabouraud dextrose agar slants potasssium sorbate, Z. bailii cells continued to grow in the (SDA) and stored at 4°C. BBL (Cockeysville, MD) Sabouraud liquid salsa mayonnaise after 28 days at room temperature. Higher broth modified antibiotic medium 13 (SDB) was made according to potassium sorbate or sodium benzoate concentrations cannot the manufacturer's directions and dispensed into 100-ml dilution be used due to government regulations and because of off bottles and autoclaved. A loopful of yeast cells from the SDA was flavors due to the preservatives (2, 14). aseptically transferred to the SDB bOllles and incubated at room temperature (23to 25°C) for two days. After incubation, a loopful of cells was transferred to a subsequent bottle of SDB. From the second 115 bottle ofSDB, 0.5 ml of yeast cells was transferred to lOOml ofDifco tryptic soy broth without dextrose containing 0.3 g of Tween 80 and 160 g of salsa mayonnaise (without preservative) and incubated at room temperature (23 to 25°C) for 22 days to provide a yeast culture acclimated to the product environment.

Inoculation of the mayonnaise and enumerating procedures

The salsa mayonnaise containing the acclimated Z. bailii cells Downloaded from http://meridian.allenpress.com/jfp/article-pdf/58/11/1257/1659760/0362-028x-58_11_1257.pdf by guest on 24 September 2021 was diluted I: 1,000 using sterile deionized water and 1.0 ml was pipetted into the stomacher bags containing the salsa mayonnaise with the various preservative levels, yielding approximately 500 yeast cells per ml. The inoculated bags were stomached for 2 min at high speed. Appropriate controls with and without preservatives and yeasts were prepared. Inoculated product was held at room temperature (23 to 25°C) and sampled for a 27-day period, enumerating Colsorbic acid exists in the Data were converted to 10glOnumber of yeast cells per gram and geometric means were obtained. Standard linear regression methods undissociated form (13), compared with 66.7% of benzoic for populations of exponentially growing cells were used to deter- acid (3), which may account for the significant degree of mine the slope. The number of generations was determined by the effectiveness seen in controlling the growth of Z. bailii for following equation: (loglo final cell concentration -Ioglo initial cell potassium sorbate compared to sodium benzoate at the same concentration)/0.301. Therefore growth rates (number of genera- preservative concentration. tions per day) were plotted versus preservative concentration, and Factors governing spoilage by microorganisms are com- the Hill model (11), a variation of the Michaelis-Menten equation, plex and may involve the environment, food composition was used to determine the relationship between growth rate and including preservatives, and processing conditions (2). So- preservative concentrations. F-tests at 95% confidence levels were dium benzoate and potassium sorbate, commonly used in ised tp determine significance for the nonlinear inhibition curves (6). acidic food products such as mayonnaise, are two antimicrobial agents whose antimicrobial activity is dependent on RESULTS AND DISCUSSION inoculum level, kind of spoilage organisms, length of shelf The antimycotic effects of potassium sorbate, sodium life, product storage temperature, pH, and preservative con- benzoate, and the two in combination in a salsa mayonnaise centration (2, 14). In this investigation, the growth of Z. bailii are shown in Figure l. The two preservatives and the combi- was not inhibited by any of the preservative systems, indicat- nations differed in their effect on the growth rate (log-phase ing a potential spoilage problem if the salsa mayonnaise is cells) of Z. bailii. Potassium sorbate was significantly (P < stored at room temperature. Since Z. bailii is a very hardy 0.05) more effective than sodium benzoate, whereas no sig- yeast, the cells can survive low pH levels and high salt nificant difference (P > 0.05) was found between potassium concentrations (8,10,12,14-16), grow in the presence ofhigh sorbate and the combination in equal proportions of the two concentrations of sorbic and benzoic acids commonly used as preservatives in controlling the growth of Z. bailii. However, preservatives (8,12,15), and exhibit adaptability to higher the combination of the two preservatives was significantly concentrations of a preservative after being grown in the more effecti ve (P <0.05) than sodium benzoate in suppressing presence of moderate amounts ofthe preservative (10,16). Z. yeast growth in the salsa mayonnaise. bailii cells have been isolated from various sources, including A reduced growth rate of Z. bailii was accompanied by a a wide variety of ingredients and unclean equipment (4, 7,9, longer lag phase and a lower cell concentration that was 14). Therefore, the key to producing a shelf-stable salsa directly related to an increase in the preservative concentra- mayonnaise is the exclusion of this yeast from the finished tion (data not presented). Even at a concentration of 0.3% product. Since no heat treatment is used to produce this

JOURNAL OF FOOD PROTECTION, VOL. 58, NOVEMBER 1995 Z. BAlLI/IN A SALSA MAYONNAISE 1259 product. ingredients. equipment, and the environment must be 5. Dakin, J. C., and P. M. Day. 1958. Yeasts causing spoilage in acetic free of Z. bailii. Consequently. the use of microbe-free ingre- acid preserves. 1. Appl. Bact. 21 :94-96. 6. Draper, N. R. and H. Smith. 1966. Applied regression analysis. p. 67- dients, clean and sanitary equipment. the judicious use of 69. John Wiley & Sons, New York. preservatives, and adherence to the tenents of good manufac- 7. Draughon, F. A., M. Elaki. and E. McCarty. 1981. Microbial spoilage turing practices during processing and packaging should of Mexican style sauces. J. Food Prot. 44:282-287. produce salsa mayonnaise free of spoilage microorganisms. 8. Ingram. M. 1960. Studies on benzoate-resistant yeasts. Acta Microbiol. Sci. Hung. 21:95-105. 9. Kurtzmann. C. P.. R. Rogers. and C. W. Hesselline. 1971. Mierobio- ACKNOWLEDGMENTS logical spoilage of mayonnaise and salad dressings. Appl. Microbiol. 21 :870-874. Thanks to Kernon Gibes. NSC Technologies, for his statisticlil assis- 10. Restaino. L.. L. M. Lenovich, and S. Bills. 1982. Effect of acids and tance. and to Dr. Hans Blaschek. University oflilinois at Champaign-Urbana. sorbate combinations on the growth offourosmophilic yeasts. J. Food for his guidance during the research for this project. Prot. 45: 1138-1142. II. Segel. I. H. 1975. Enzyme kinetics: behavior and analysis of rapid REFERENCES equilibrium and steady-state systems., p. 360-361. John Wiley & Son. New York. Downloaded from http://meridian.allenpress.com/jfp/article-pdf/58/11/1257/1659760/0362-028x-58_11_1257.pdf by guest on 24 September 2021 I. Appelman. M. D .• E. P. Hess. and S. C. Rittenberg. 1949. An investi- 12. Smittle, R. B. 1977. Microbiology of mayonnaise ",nd salad dressing: gation of a mayonnaise spoilage. Food Technol. 3:20 I-203. a review. J. Food Prot. 40:415-422. 2. Chichester. D. F.. and F. W. Tanner. 1972. Antimicrobial food addi- 13. Sofos.J. N. 1983. Sorbates.,p 146.//1 A. E. Branenand P. M.Davidson tives. p. 115-137.//1 T. E. Furia (ed.). Handbook of food additives. (ed.), Antimicrobials in foods. Marcel Dekker. Inc. New York. vol. I. 2nd ed. CRC Press. Inc .. Boca Raton. FL. 14. Sofos. J. N. 1989. Sorbate food preservatives., p. 39-41,99-101. 142. 3. Chipley. J. R. 1983. Sodium benzoate and benzoic acid .• p. 13./1/ A. CRC Press. Inc .• Boca Raton. FL. E. Branen and P. M. Davidson (ed.). Antimicrobials in foods. Marcel 15. Walker. H. W. 1977. Spoilage offoods by yeast. Food Technol.3I :57- Dekker. Inc .. New York. 61. 4. Chung, S. L.. K. V. Jorgensen. and R. L. Price. 1988. Effects of /6. Warth. A. D. 1977. Mechanism ofresistance of Sacclwromyces bail;; processing temperature and addcd antimicrobial agents on keeping to benzoic. sorbic and other weak acids used as food preservatives. quality of Mexican style sauces. J. Food Sci. 53: 1163-1164. J. Appl. Bact. 43:215-230.

JOURNAL OF FOOD PROTECTION. VOL. 58, NOVEMBER 1995