Phuket Msrine Biological Center Special Publication 25(1): 221-224 (2001) 221

Smoke curing of trapezium meat (: )

C. Felicia Shanthini & |amila Patterson

Shanthini, C.F. & J. Patterson. 2001. Smoke curing of Pleuroploca trapezium meat (Gastropoda: Fasciolariidae). - Phuket Marine Biological Center Special Publication 25 (l): 227 -224.

Best quality of the smoked meat of Pleuroploca trapezium was obtained after 5 min of blanching in 5 % brine and 45 min of smoking. The microbial load decreased substantially with the increase of smoking time. Biochemical and organoleptic analysis were also carried out and their nutritive value and consumer preference were included.

C. Felicia Shanthini I lamila Patterson. Suganthi Deaadason Marine Research Institute,44, Bench Road, Tuticorin 628 00L, India.

E-mail : s dmr [email protected] snl.net.in

INTRODUCTION preservation of fish and also to impart the The horse , Pleuroploca trapezium is smoky flavour since time immemorial. available in all seasons along the southeast Smoking is often combined with a period of coast of India with a peak from January to ]une sun drying and/or preliminary brining. and a lean season from October to December, Smoking combines cooking and drying of the due to less fishing activities during the meat due to the high temperature produced monsoon season. They are collected by trawl by smoking. This dries the meat, destroys the net, lobster net and skin diving. The total enzymes and kills bacteria. Apart from this the landings of P. trapezium along southeast coast smoke contains a large number of compounds of India during the year 1991-92 was 441 tons some of which, e.g., phenols will kill bacteria. and increase dto 627 tons during the year 1,992- The long storage life of some smoked meat 93 (Patterson Edward 1992, 1993, 1994) products is more due to drying and cooking The foot and the adductor muscle are than to the preservative value of the chemical consumed by a small section of the fishermen compounds deposited on the meat from the community. The meat is not popular like other smoke. In the present study, the rn^eat of P. seafoods because of food preferences and lack trapezium was smoked and the quality of the of knowledge of its delicacy and nutritive final product was assessed. value. Howeve4 after 1991,, it gained market value and is now being exported to Southeast MATERIALS AND METHODS Asian countries. At present, the meat value is Fresh P. trapezium meat was procured from the Rs. 60 / kg. The meat is tough and takes a long fishermen and brought to the laboratory. One time to soften by conventional cooking. Thus gram of raw meat was taken before cleaning it is generally sun dried and eaten after frying. for microbial analysis to enumerate the total Smoking offers an alternate method for heterotrophic bacteria and Solmonella sp. The utilization of the meat. It obtains a longer shelf meat was cleaned to remove the mucous and life and characteristic flavour. Smoking has dirt in the foot muscle, and cut into thin been considered as a technique for rounded slices of about 1 mm thickness. 20 o 222 Tropical Marine Mollusc Programme (TMMP)

of the raw meat was dried in oven at 55 to 60 the tissue. The salt content was determined by 'C for moisture and biochemical analysis. The taking one gram of sample and homogenizing remaining meat was divided into 3 equal parts in distilled water to thoroughly extract the salt. and blanched in 5, 10, and 15 % boiling brine It was centrifuged and 5 ml of the supernatant for 5 minutes. The blanched meat was drained was titrated with silver nitrate. The volume and spread on trays and dried for 20 minutes of silver nitrate used was proportional to the to facilitate smoke penetration. salt content. A conventional vertical type smoking kiln The carbohydrate . content was estimated by was used for smoking the meat and burning the phenol sulfuric acid method (Dubois et al. sawdust generated smoke. The meat blanched 1956) protein by Biuret method (Raymont ef at different concentrations of brine was a\.7964) and lipid content by using chloroform smoked. During smoking samples were methanol (Folch et a\.1956). drawn every 15 minutes to observe the effect The organoleptic characteristics like colouq, of smoking time on the quality of the meat. flavour and overall acceptability of the For enumeration of bacteria, one gram of the smoked meat were evaluated on a 5 point sample was macerated with distitled water hedonic scale. The limit of acceptability was and serial dilutions of the samples were made fixed at 3. in distilled water. Pour plate method using Zobell's marine agar medium and Xylose RESULTS AND DISCUSSION Lysine Deoxycholate agar medium enumera- Table 1 shows the effect of salt concentration ted the total heterotrophic bacteria and on the quality of smoked meat. The salt Salmonella respectively. Plates for estimates content was found to increase with increased of THB and Salmonells were incubated at 37 concentration of brine and oC smoking time. The for 48 and 24 hrs respectively. Bacterial salt taste was normal in the meat blanched in colony counts were made and expressed as 5 % brine. The taste was too salty in meat Colony Forming Unit (CFU)per gram. blanched in 10 and 15 % brine. Based on the The moisture content was calculated by the organoleptic analysis, the meat blanched in difference between the wet and dry weight of 5 % brine and smoked for 30 minutes had a

Table 1. Effect of salt concentration on quality of smoked meat of Pleuroploca trapezium.

concentration of smoking time salt content remarks brine (%) (minutes) e/"\ 15 3.4 partial smoke absorption. 30 4.0 fully smoked & salt taste normal. 5"/" 45 4.L smoky odour marks the taste. 60 4.2 smoky odour marks the taste.

15 4.5

30 5.5 r0% predominantly saltish. 45 6.3 60 6.5

15 5.0

30 6.2 $% highly saltish 45 8.2 50 8.3 Phuket Marine Biological Center Special Publication 25(1): 221-224 (2001) zzJ

golden brown colouq, good flavour and taste. The proximate composition of smoked meat After 45 and 60 min of smoking, the meat taste is presented in Table 4. The carbohydrate and was very smoky. protein content of smoked meat were found Table 2 shows the effect of smoking time on to decrease with increased smoking time. the quality of smoked meat. The moisture Dudek & Elkins 1997 quotedMcCain & Shipp content of the meat smoked for 15 minutes was (1933), who found that liquid may be lost as 11.4% and it gradually decreased to 5.3 "/o after drip along with soluble minerals and non- smoking for 60 minutes. Smoking of meat protein nitrogen during hot smoking. In removes water. The water activity (Aw) of a general, the application of heat to food, as in foodstuff is the water available to support the the case of smoking, causes a reduction on the growth of microorganisms. Moisture levels of quality of constituent proteins (Dlllon et aI. meat also play an important role in the 1994). According to Hovner (1,997) the spoilage. Lowering of moisture retards deposited smoke components have reacted spoilage (Stansby 1963). As water is essential with the proteins of flesh resulting in the for the activity of all living organisms its reduced biological availability of protein. In removal will slowdown or stop microbial or contrast, the lipid content was found to autolytic activity, thus smoking is used as a increase slightly with the smoking time. This method of preservation. is because cooking may concentrate the lipid Table 3 shows the microbial analysis of fraction due to loss of moisture. smoked meat. The number of colonies of total Tabte 3. Microbial analysis of the smoked Table 2. Effect of smoking time on moisture meat of Pleuroploca trapezium blanched in content and the quality of smoked meat of 5 % brine. A : Smoking time, B = Total Pleuroploca trapezium blanched in 5% brine. Heterotrophic Bacteria, C = S almonella. A smoking time, B : moisture content. = AB C AB (min) (CFU x 10s) (cFU) quality of the product (min) (7') 15 5.7 nil 015 raw meat 30 4.5 nil

11.4""@ 45 4.8 nil 15 sticky to touch. 60 0.7 nil 11 1 uni{ormly smoked, golden 30 brown colour, good flavour Table 4. Proximate biochemical compo- dark brown colour, 45 8.4 smoked of Pleuroploca unattractive. sition of meat trapezium blanched in 5 % brine. unattractive, very 60 5.3 dark brown colour. smoking lipid carbohydrate protein time content content content (min) (%) (%) (%) heterotrophic bacteria in the samples 15 3.4 t7.6 29.34 decreased with smoking time. There was a 4.8 12.7 14.18 direct relationship between the smoking time, 30 moisture content and microbial counts of the 45 4.8 11.1 L3.76 samples, thus confirming the fact that smoking 60 4.0 4.1 12.r4 reduces the water activity and hence the microbial count. Also the chemical Table 5. Show the organoleptic characters of constituents of smoke itself provide the smoked meat. The meat blanched in 5 % bactericidal action and antioxidant properties brine and smoked for 30 min scored the (Hovner 7997). Salmonelln sp. was not detected highest marks in terms of colour, flavour, and in any of the smoked meat analyzed. overall acceptability. The meat pieces smoked 224 Tropical Marine MoIIusc Programme (TMMP)

Table 5. Organoleptic characters of smoked Folch,J., M.Lees & G.H.S.Stanly, 7956. A meat of Pleuroploca trapezium blanched in 5% simple method for the isolation and brine. Colour, Ilav our, and overall acceptability purification of total lipids from are evaluated on a scale from 0 to 5. tissues. - Journal of Biological Chemistry, smokins overall colour - 226:497-509. tlme u.avour acceptabthty Hovner,W.F. A. 1997. Preservation of fish by 15433 curing (drying, salting and smoking). In Fish 30455 Processing Technology. G.M.Hall (Ed.) CH 45333 Blackie Academic & Professional, pp 33-73. 60 122 Patterson Edward,J.K & K.Ayyakk annu, 7992. Economic importance of the gastropod for 15 and 30 min were acceptable, but after Fasciolariq trapezium, an important seafood 60 min the meat was poor in terms of colour resource occurring along the southeast coast and flavour. It was unacceptable. of India. - Phuket Marine Biological Centre Special Publication, 10: 77-19. Patterson Edward,J.K., A.Murugan & REFERENCES K.Ayyakkannu, 7994. Landing data and Dillion,R., T.R.Patel & A.M.Martin, 1,994. meat trade with Chicoreus rqmosus and Microbiological control of fish smoking Pleuroploca trapezium in the Gulf of Mannar operations. In fisheries Processing: and Palk Bay, Southeast coast of India. - Biotechnological applications. A.M.Martin Phuket Marine Biological Centre Special (Ed.) Chapman and Hill Londory pp 57-76. Publicatiory 13:37-42. Dudek,J.A. & E.R.Elkins Jr., 7997. Effects of Raymont J.E.C., A.Austin & E.Linzford,7964. cooking on the fatty acid profiles of selected Biochemical studies on marine zooplankton. sea foods. Health effects of polyunsaturated i. Biochemical composition of I'leomysis fatty acids in sea foods, p.431-450. integer. - Journal of Cons.Perm.Exlor. mer. 28: Dubois,M., K.A.Gillea J.K.Hamiltory Befors & 354-363. F.Smith, 1956. Colorimetric method for Stansby,M.E . 7963. Curine of fishery products. determination of sugars and related In Industrial Fishery Technology. M.E. substances. - Analytical Chemistry. 28:350- Stansby and ].A. Dassow (Eds.) Rainhold 356. Publishing Corporatiory pp 475.