'.I'fct IF" OPTING and SENSORY QUALITY Dry SAUSAGE
Total Page:16
File Type:pdf, Size:1020Kb
'.I'fCT OF THE USE OF NATURAL OR of using either a natural pork casing or IF" CASINOS ON THE an artificial fibrous collagen casing on 5 f,cial OPTING AND SENSORY QUALITY the ripening and sensory quality of a dry SAUSAGE. mouldy dry fermented sausage. For this p study, a sausage of high comercial b a n c a l e s , m . a g u ile r a , j .a . interest in Spain known as «fuet» was l'Ra n - • JAIME•* — and■ J.M,-------- PEIRO. selected, whose determinant characteristics are those of a small > Pp. AL 1 Ac c ió n Animal y Ciencia de los calibre, coarse and mouldy salami. C * * Facu1tad Veterinaria. rsidad de Zaragoza. SPAIN. MATERIALS AND METHODS Sausages were prepared by a local P r o d u c t i o n manufacturer according to usual SaySgUa,ity of raw fermented practice. Each sausage, averaging 340 g f>ararr|^es is influenced by a number of in weight, contained 70% lean pork, ribenieters which govern sausage 25% pork back fat, 2.3% salt, lactose attent"^ amon9 them especial (1.7 g), glucose (680 mg), black pepper reia^.,0n has been paid to temperature, (680 mg), white pepper (680 mg), ^leKVe humidity and air velocity nutmeg (250 mg), sodium glutamate n^r anc) Rodel, 1978; Baumgartner (340 mg), sodium ascorbate (170 mg), ’hflUen 98° ; hendoza et a1-F 1983). The posphates (680 mg), nitrate and nitrite ^ l )tvCe on ripening and sausage (85 mg), colouring (E-124, E -127) and Sq ^ of a variety of ingredients has starter culture (Pediococcus spp.). H ^ v<I en more extensively studied. Mixture was stuffed into either pork or ^opertr" cles,:)' te our knowledge of the fibrous collagen casings of 34-38 mm 's rathleS 0f diverse sausage casings diameter. Sausages were held 24 h at % c teorf 9o°d (Effenberger, 1985), the 28°C (90% RH) and then transferred to CaSir,gof tde use of different kinds of a drying room, which was a well H n 0r^ Sausage quality is not well aerated chamber subject to natural W L Rödel and Klettner (1980) climatic conditions, and ripened for 30 S^aqe snnall differences on dry days. During this period temperature S ^ a i r ’pen'n9 by effect of using ranged from 11°C to 14°C and relative ° r a rtiticial casing, while humidity varied from 75% to 80%. J'fferen ^984) described large Samples were taken at different N gesCes in quality among cooked ripening times: 1,5, 10, 15, 20, 25 and related to the use of diverse 30 days. A sufficient amount of Thoatena1s- sausage was ground after removing the ^aUsQge^u9ti, both reports deal with casing to a particle diameter smaller h9s been acl<in9 a mould cover, which than 1 mm, using a commercial meat grinder. The resultant mixture was fc,Ceat>leei!?,tetlly shown t0 exert a Gr 'ty (r, nr'u^nce on dry sausage used for all analyses. r^iaet ^a90ni and Cantoni, 1984; M o istu re d e term in atio n . About 3 ThUsa ’ 1986; Lücke, 1986). g of sample were exactly weighed ’ we have studied the effect and held at 102 + 2°C for 19 hours; 8 2 5 after cooling the sample was weighed cross sections. Samples for rn,ci ^ again. Water content was expressed as copical observation were taken at the percentage of the difference end of sausage ripening. Five prn ^ between initial and final weight sections were cut from small PieceL' related to initial value. sausage with a microtome and sta Fat content was determined with hematoxiline-eosine. A L,flr using a Soxhlet method (ISO/R 1443). (Dialux 20 EB) microscope was Nonprotein nitrogen determi observing the stained sections p nation. Ten g of sample were photographs were taken using 3 ^ homogenised for 1 min in 35 ml (model FX-35A) camera. efe distilled water using an Ultra-Turrax Sensory analysis Sausages y ^ homogeniser. Seven ml 10% TCA were evaluated for 19 quality're* 0f added to the homogenate and, after sensory parameters at the en ^ maintaining the mixture 2 h at 4°C, it ripening by a panel of ^ $ was centrifuged for 20 min at lOOOxg. semi-trained members. A 9-point b $ The supernatant was filtered, was used, 9 denoted highest valu^ | evaporated and protein content each parameter evaluated determined by a Kjeldalh method denoted lowest value. Analyse5 5; (ISO/R 937). performed in three separate seS5jP of Free fatty acids (FFA) deter in each of them a different mination. Fat extraction was carried sensory parameters was eva Uent^ out with chloroform-methanol solvent First whole sausages were Pre ^1 (2:1 vol/vol). Then 25 ml were removed to panelists for valoration of eXl ^ and mixed with 25 ml 96% ethanol. The perception. Thereafter panelist5 ^ mixture was titrated with NaOH 0.1 N. luated 3 mm sausage slices f°r j|/ The acidity was calculated as oleic external perception and finally 51 $ acid (Pearson, 1976). slices, after removing the casing' ^ Microbiological analysis Three presented to each panel memP casing portions of 1 cm2 surface were mouth perception evaluation. taken from different areas of each whole sausage. Samples were RESULTS AND DISCUSSION ^ suspended in sterile physiological «Fuet» sausages were rlPene’ ^ solution and suitable dilutions were natural conditions (11-14°C; ' made before plating. Total superficial R.H.) for 30 days after a short P ^ mould and yeast counts were deter fermentation at 28°C for ^ ^ mined on Sabouraud Chloramphenicol (90% R.H.). Along the ^ # agar incubated at 20°C for 7 days. fermentation and ripening Per’ ^ After microculture on Sabouraud agar, following physical and cnj5t/ isolated moulds were identified by parameters were measured: ^ ^ microscopical observation techniques content, pH, free fatty acids 3(] according to Ramirez (1982). Yeasts protein nitrogen. Onjtioil were stained by Gram and Giemsa Figure 1 shows moisture e methods and observed microscopically. along sausage ripening for P° Light microscopy of sausage materials used. It appears 8 2 6 Figure 2 Changes of pH during ripening process. ( ■ natural casing, □ artificia l casing). S s . - °agS ■ Evolution of Free Fatty Figure 4 - Changes of nonprotein ^¡0/10QeXf)ressecl as percent of oleic nitrogen fraction during sausage * natij ^ of fa t- alon9 ripening. ripening. (■ natural casing, □ artificial aî casing, □ artificia l casing). casing). L a^r9oe Cases moisture content water vapour as described by r^^ent an inr,P°rtant decrease, in Effenberger (1985). ,^ilar wit;h previous reports for Changes in pH along ripening for Bauausa9es (Rodel and Klettner, both types of sausage are shown in ^ l9 8 ^ m9artner et al., 1980; Lois et Figure 2. In agreement with most prior ’Hg Us ’ ^°n dependent on the type of research reports ( Baumgartner et al., % ' ln accordance with their 1980; Rodel and Klettner, 1980; ehtical permeabilities to Barranco et al„ 1985; Lois et al., 1987) 8 2 7 pH decreases dramatically within the previously reported by Palumbo first few days of fermentation while it Smith (1977), León and Míllán (,9 nfl is not modified or increases gradually and Lois et al. (1987), although throughout ripening. As evidenced by studies have been as yet rePortefgtJ the curves obtained, sausage stuffed in the effect of casing upon free natural casing reaches significantly acid content. ^ higher pH values from 5th day on, as Nonprotein nitrogen evoi^ ^ was already demonstrated to a lesser throughout ripening, generally scceP is as a measure of proteolytic reach extent by Rodel and Klettner (1980). 0« According to Grazia et al. (1985) depicted in Figure 4. As it cante(- this pH rise ought to be referred most observed no variation in this ParafTlpe likely to a decrease in lactic acid appears to be evident, at the same1 ^ content rather than to ammonia that no differences between cas ^ formation, and it is to be related to used are noticeable. This somed mould mycelia colonization of sausage surprising result is in disagree^. mass and casing. with those described by DiericK e . As shown in Figure 3 free fatty (1974), Bello et al. (1974), Leóne acid content increases considerably (1978) and Lois et al. (1987), a,th% along ripening in a more or less lineal increases reported by them are - )e small or even negl'9 fashion with no noticeable differences very U5* between both types of casing used. Relationship of this fact with tPe^ i General behaviour agrees with that in our sausage mixture ta' Table !.- Superficial mould and yeast counts and respective percentage over W microorganism number along ripening of sausages stuffed into either natuf a rtificia l casing. Natural casing A rtificial casing Moulds (Peniciinum) Yeasts Moulds (Pénicillium) Yeasty 7» Days No/cm2 % No/cm2 % No/cm2 % No/cm2 SO*“ 1 4.16x 102 47.05 1.64x102 18.54 2.37X102 0.65 1.80x104 494 5 2.22x1 Ü3 20.83 8.90x104 80.20 4.16x10s 50.29 4.10X105 574' 10 1.49x106 71.34 6.00x10s 20.09 1.05x106 42.59 1.40x10S 3Ü.S4 15 2.06x106 83.07 4.20x10s 16.95 1.72x106 59.67 1.16X106 1 $ 20 2.49x106 94.28 1.50x10s 5.72 2.28x106 73.43 8.20x10S 25 1.92X1Q6 92.16 1.30x10s 6.40 1.13x106 65.38 6.00X105 8 2 8 >0, Coccus starter culture is never- the end of ripening their number is ess not known, slightly higher in natural casing, f ^'croorganism identification and constituting a much larger percentage c°unt beer)v1n9 °n sausages along ripening has of total microorganisms present than PeeiJ"arr1ed out only in both casings in artificia l casing.