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Journal of Food Protection, Vol. 49, No. 4, Pages 280-281 (April 1986) Copyright® International Association of , Food, and Environmental Sanitarians

Evaluation of Summer Sausage Manufactured Using Mixed and Leuconostoc Starter Culture1

O. J. BURROWES2, F. H. SCHMIDT*, K. L. SMITH and J. V. CHAMBERS3

Food Science and Human Nutrition Department, University of Florida, Gainesville, Florida 32611 Downloaded from http://meridian.allenpress.com/jfp/article-pdf/49/4/280/1656976/0362-028x-49_4_280.pdf by guest on 29 September 2021 (Received for publication August 9, 1985)

flavor compounds and sensory acceptance of sausage ABSTRACT manufactured with the Leuconostoc sp. with that man­ ufactured using a more traditional sausage culture such A 1:1 mixture of Leuconostoc and Lactobacillus plantarum and of L. plantarum alone were used as starter-cultures in mak­ as Lactobacillus plantarum. ing two batches of summer sausage. Sausage samples were evaluated for volatile flavor compounds and by sensory evalua­ MATERIALS AND METHODS tion. Ethanol was the primary volatile flavor compound in the Microorganism and growth conditions sausage from mixed culture while acetaldehyde predominated in The microorganisms used in this study were obtained from the single culture sausage. Sensory evaluation indicated a sig­ the American Bacteriological and Chemical (ABC) Research nificant difference (p=£0.01) between the two types of sausages Corporation, Gainesville, FL. These included L. plantarum with 66% of the panelists preferring sausage prepared with L. routinely used as a starter culture in commercial summer saus­ plantarum alone. age manufacture and Leuconostoc sp. isolated from commercial fermented sausage and being investigated for use as a starter culture. Growth and maintenance of these organisms has been Use of starter culture, as opposed to "back slopping" described previously (2). from a previous batch, in the manufacture of fermented meat has received considerable interest in recent years. Summer sausage preparation Most used as starter cultures are the homofermentative Two batches of a 'typical' summer sausage formulation were , such as species and Lac­ prepared as shown in Table 1 and a 1% inoculum either of tobacillus species, which produce lactic acid as the major L. plantarum or of a 1:1 mixture of Leuconostoc and L. plan­ carbohydrate metabolite giving the characteristic, tangy tarum was added. The sausage mixes were stuffed into fibrous taste of fermented sausage. The heterofermentative bac­ casings and hung in a green-room until the pH of the sausage teria, such as many Leuconostoc species, which produce dropped to 5.0 (appx. 16 h). other metabolites in addition to lactic acid, may be im­ portant in the flavor of fermented sausage as wild type Volatile flavor compound analysis Samples were taken for analysis at 0 h, at the time required contaminants. However, they are not used extensively as for pH drop to 5.0 (16 h) and after refrigerated storage (72 h). starter organisms. Among the volatile flavor compounds Ethanol, acetaldehyde, diacetyl and acetoin levels were mea­ generally produced by are acetal­ sured using Headspace Gas Chomatography (HSGC) by a mod­ dehyde, diacetyl, ethanol, and acetic acid (3-6). Produc­ ification of the procedure of Marsili (7). A Sigma 3B gas tion of these compounds has primarily been examined in chromatograph with HS6 headspace sampler (Perkin Elmer milk or broth cultures. Flavor compound production re­ Corp., Norwalk, CN), connected to a Hewlett Packard integ­ lated to lactic acid bacteria in fermented meats has only rator model 3390A (Hewlett Packard Co., Corvallis, OR) and been sparingly investigated (7). a glass column (1/8 in. x 6 ft) packed with Porapak S (Supelco, Inc. Bellefonte, PA) were used. Temperature prog­ In a previous investigation (2), flavor compound pro­ ramming was used in which temperature varied between 130- duction as affected by various growth conditions in broth 190°C with an initial holding time of 2 min and a ramp rate cultures of Leuconostoc sp. originating from sausage was of 5°C per min. The injection temperature and detector tempera­ evaluated. The objective of this study was to evaluate the ture were 250 and 200°C, respectively. Into headspace sample vials was placed, 1.0 g of sausage and 'Florida Agricultural Experiment Station Journal Series No. 6679 • 1.0 ml of bottler's acid. Bottler's acid, prepared by mixing 2Present address: College of Arts, Science and Technology, 237 Old anhydrous citric acid (2.508 g) and 85% phosphoric acid Hope Road, Kingston 6, Jamaica, W.I. (10.424 g) and making to 1 L with water, was used to stablize *ABC Research Corporation, Gainesville, FL 32601. pH and maximize flavor volatility (2).

JOURNAL OF FOOD PROTECTION, VOL. 49, APRIL 1986 EVALUATING CULTURES FOR SUMMER SAUSAGE 281

TABLE 1. Formulation used in sausage manufacture. TABLE 2. Comparison of ethanol and acetaldehyde levels dur­ Level used ing of summer sausage using single or mixed star­ Ingredient (g) ter cultures. 0 Lean beef (10% fat) 908.0 Flavor-related compounds Beef trim (50% fat) 908.0 Culture Incubation Ethanol Acetaldehyde Diacetyl b Salt 124.8 system" time Dextrose 90.0 Single Ground nutmeg 2.8 culture 16 N.D.d 15.3 N.D. Ground white pepper 17.0 72 N.D. 19.0 N.D. Ground coriander 6.0 Mixed All spice 1.5 culture 16 1.21 (-10.1) N.D. Sodium erythorbate 2.4 72 1.16 (- 1.3) N.D. Prague powder 11.3 "Single culture is L. plantarum while mixed culture is a 1:1

mixture of L. plantarum and Leuconostoc sp. Downloaded from http://meridian.allenpress.com/jfp/article-pdf/49/4/280/1656976/0362-028x-49_4_280.pdf by guest on 29 September 2021 The headspace vials were sealed with Teflon lids and were bHours of incubation. Times correspond to time required for equilibrated at 80°C for 30 min. Following a 30-s pressuriza- pH reduction to 5.0 (16 h) and time of sensory evaluation tion, a 5-s injection was made. Concentration of volatile flavor (72 h). components was determined by comparison of peak areas to cNet production of ethanol (ixmoles g"1) and acetaldehyde those for standard curves. Data, corrected by subtraction of data (nanomoles g"1). Determined by headspace gas chromatography from sausage blanks (at incubation time 0), are presented as (HSGC). Means from duplicate trials. ixmoles per g of sausage. dNot detectable (less than 0.1 |xg/g).

Sensory evaluation of sausage Sensory evaluation of the sausage products was done using a triangle test with 50 untrained panelists. Panelists were asked a difference between the sausage made using the mixed to detect the differences between sausage prepared with single culture L. plantarum (control) and with mixed Leuconostoc and culture and that using Lactobacillus species alone. Indi­ L. plantarum and, in addition, were asked which sausage sam­ viduals who preferred the flavor of the Lactobacillus type ple was preferred. sausage (66% of panelists) commented on its more tangy flavor while those who preferred the sausage made with RESULTS AND DISCUSSION the mixed culture (34%) suggested a more mellow spicy flavor. Ethanol and acetaldehyde levels in summer sausage Most sensory panelists in this study preferred the flavor After 16 h of incubation, the pH had decreased from of the sausage produced using the Lactobacillus species the initial value of 5.8 to 4.9 for single culture (L. plan­ only as starter culture. This is probably due to traditional tarum) and to 5.1 for mixed culture (1:1 mixture of L. expectations of consumers accustomed to more tangy plantarum and Leuconostoc). As shown in Table 2, the sausage. Those disliking the mixed culture sausage were primary volatile flavor metabolite produced by L. plan­ not appreciably offended by the flavor. It is conceivable tarum in single culture was acetaldehyde. Comparing data that there may be future acceptance of this type of flavor for 16 and 72 h, it was noted that the acetaldehyde level in specialized sausage fermentation applications. in this sausage increased slightly during storage at 4°C. The primary volatile metabolite determined in sausage REFERENCES produced with mixed L. plantarum and Leuconostoc cul­ 1. Acton, J. C. 1977. The chemistry of dry sausages. Proc. Recip. ture was ethanol. As observed in the previous study using Meat Conf. 30:49-62. broth culture (2), no diacetyl was produced in the sausage 2. Burrowes, O. J. 1985. The effect of temperature, pH and oxygen by Leuconostoc sp. Diacetyl and acetoin production gen­ on production of flavor producing compounds by Leuconostoc erally involves citrate metabolism in Leuconostoc or­ species isolated from fermented sausage, M.S. Thesis. Univ., of ganisms such as Leuconostoc cremoris. However, some Florida, Gainesville, FL. 3. El-Gendy, S. M., H. Abdel-Gabil, Y. Shahin, and F. Z. Hegazi. strains of Leuconostoc dextranicum and L. cremoris can 1983. Acetoin and diacetyl production by Lactobacillus casei subsp. use citrate without concomittant diacetyl production {4,5). pseudoplantarum. J. Food Prot. 46:537-541. Since Leuconostoc sp. used acetaldehyde for ethanol pro­ 4. Keenan, T. W. 1968. Production of acetic acid and other volatile- duction, a negative net acetaldehyde production level was compounds by Leuconostoc citrovorum and Leuconostoc de­ observed in the sausage from the mixed culture. At the xtranicum. Appl. Microbiol. 16:1881-1885. time of sensory evaluation, the acetaldehyde level de­ 5. Keenan, T. W., and D. D. Bills. 1968. Metabolism of volatile com­ pounds by lactic starter culture microorganisms: A review. J. Dairy tected in sausage from single culture was 33.2 nanomoles 1 1 Sci. 51:1561-1567. g" compared to 18.4 nanomoles g' for sausage from 6. Lawrence, R. C, T. D. Thomas, and B. E. Terzaghi. 1976. Re­ mixed culture. views of the progress in dairy science: cheese starters. J. Dairy Res. 43:141-193. 7. Marsili, R. T. 1981. Monitoring baterial metabolites in cultured but­ Sensory evaluation of summer sausage termilk by high performance liquid chromatography and headspace Of 50 panelists tested, approximately 55% recognized gas chromatography. J. Chrom. Sci. 19:451-456.

JOURNAL OF FOOD PROTECTION. VOL. 49, APRIL 1986