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ThesisItem Open Access Tenderisation of buffalo meat by calcium chloride marination(Department of Livestock Products Technology, College of Veterinary and Animal Sciences, Mannuthy, 2006) Kavitha, Rajagopal; KAU; George, T OommenThe present study on the tenderisation of buffalo meat by calcium chloride marination was designed to assess the effect of marination on tenderness and other organoleptic qualities of meat and to compare the effects with those of natural ageing. Samples of longissimus dorsi muscle between 9th and 12th thoracic vertebrae from 14 healthy crossbred Murrah buffaloes of 4 – 8 years old were collected. They were assorted for three treatments, viz., samples neither aged nor calcium chloride marinated; and stored at room temperature for 6 h postmortem (NAM), samples aged only (A), samples which are marinated (AM). Samples of A and AM were stored at 2-4o C. The aerobically packaged samples for the treatment AM after 24 h of storage were marinated by injection with 200 mM calcium chloride solution (5% w/w) at multiple sites. The pH, WHC, cooking loss, color, MFI, WBSF and sensory quality attributes such as juiciness, ease of fragmentation, amount of connective tissue, overall tenderness, flavour intensity and colour of the steaks were assessed. The samples for the treatment NAM were subjected to the study at 1 h and 6 h and the steaks from A and AM at 1 h, 6 h and on days 1, 2, 4, 6 and 8. The pH of the steaks was not affected by CaCl2 marination. It followed the normal postmortem pattern, with a pH of 6.7 ± 0.01 at 1 h in all treatments. The ultimate pH of 5.6 reached on day 1 was significantly lower (P < 0.05) than on all days, which gradually increased until day 8 in treatments A and AM. The samples followed a normal rigor with sufficient amount of m-calpain and the increase in pH was due to the accumulation of products of proteolysis. The WHC at 1 h was 0.37 ± 0.021 which declined to a significantly lower (P < 0.05) value of 0.31± 0.021 at the ultimate pH on day 1. This remained almost static till day 8 in both treatments A and AM. On day 1 the pH and calcium induced shrinkage caused loss of water. Later changes in the cytoskeleton improved WHC by removing rigor induced shrinkage of myofibrils. WHC was not significantly affected by calcium chloride marination. The percentage of cooking loss increased significantly (P < 0.05) on da 1 and thereafter it remained static till day 8. Calcium chloride was not found to affect the percentage of cooking loss. The comparatively higher loss observed in the study could be attributed to the lack of external fat covering and marbling in the buffalo LD steaks. Ageing is found to improve the colour of fresh meat from day 1 onwards. But calcium chloride marination did not have any additional effect on the colour of aged meat. The decline in postmortem pH to 5.6 on day 1 contributed to higher L, a, b values which increased the light scattering properties. On subsequent days, L, a, b values remained without significant changes. This could be due to the antioxidant action of amino acids and dipeptides formed during postmortem proteolysis, which preserve the methmyoglobin reducing activity. In treatments A and AM the MFI followed a gradual significant decrease (P < 0.01) from 768.0 ± 40.52 to 541.78 ± 34.63 on day 1 and day 8, respectively in aged steaks. While in marinated it declined to 465.28 ± 29.79 on day 8. Significantly lower (P < 0.01) value of 630 ± 42.88 on day 2 in marinated samples was comparable to that in the aged samples on day 4, indicating the early achievement of tenderness in marinated samples. MFI varied little with ultimate pH. MFI is deemed as a very useful indicator of meat tenderness particularly when sample size is smaller for the determination of shear force or sensory evaluation. Significantly highest (P < 0.01) WBSF value of 11.37 ± 0.61 obtained on day 1 could be attributed to rigor induced shortening. The values declined significantly in treatments A and AM. The values obtained for the marinated steaks were significantly lower (P < 0.01) than the aged samples on all days postmortem. It reduced from 10.48 ± 0.48 at 1 h postmortem to 4.88 ± 0.45 in a course of 8 days. This indicated a 53.44% reduction in values from 1 h to day 8, while in aged sample only a 35.59% reduction was noticed in a course of 8 days. The sensory panel evaluation of organoleptic qualities showed that calcium chloride marinated steaks significantly improved (P < 0.01) in the scores for the different attributes studied on each day of ageing. No flavor problems or alterations in cooked color were noticed at 200mM CaCl2. Correlation studies in between MFI and WBSF revealed a significant positive correlation (P < 0.01) with r = 0.85 in A and 0.84 in AM on all days from 1 to 8. This indicates that MFI could be used as an indicator of tenderness of fresh meat rather than cooked. WBSF and MFI were strongly correlated with the overall tenderness measured by taste panel evaluation. The overall tenderness was more negatively correlated with SF (r = 0.70) rather than MFI (r = 0.65). The tenderness and other organoleptic qualities of buffalo longissimus steaks could be improved significantly by post-rigor marination with 200mM CaCl2 (5 % w/w) on day 1 and subsequent ageing at 2 – 4o C for 4 – 8 days. The tenderness improved by 53.44 per cent in marinated steaks as against 35.59 per cent in those aged without marination. The improvement in tenderness could be attributed to the activation of μ- and m-calpain by calcium ions and the autolysis of calpastain at 2 - 4o C of ageing.ThesisItem Open Access Effects of preslaughter stress and irradiation on physicochemical qualities of meat(Department of Livestock Products Technology, College of Veterinary and Animal Sciences, Mannuthy, 2006) Vivek, A K; KAU; Kuttinarayanan, P (Guide)The effect of stress on the blood parameters and physicochemical qualities of meat as well as effect of irradiation on the qualities of fresh meat from stressed cattle were investigated in the present study. A total of 27 culled adult cattle from different farms were grouped into three, having nine animals in each group. Group I animals were considered as control while group II animals were transported for 2 h and slaughtered immediately after transport. Group III animals were transported for 6 to 7 h and given rest for 18 h before slaughter. Blood samples were collected prior to transport in all the animals, immediately after transport in group II and III and after 18 hours rest, before slaughter, in group III animals. Meat samples were collected from all the animals in which half of the samples were subjected to irradiation at 2.0kGy with gamma irradiation, as Cobalt 60 as source. The samples were stored at 40C for further studies. Animals in all the groups were having homogenous blood values prior to transport in cortisol, CK, BUN, creatinine and PCV. After transport, group II had a significant increase in cortisol (P<0.01), CK (P<0.01) and BUN (P<0.05), while group III had a significant increase in cortisol (P<0.01), CK(P<0.01), BUN (P<0.05) and creatinine (P<0.05) except PCV, in which the increase in cortisol and CK were significantly (P<0.01) greater than that in group II. By giving rest, even though there was significant (P<0.01) reduction in cortisol and CK values, the after rest values of cortisol (P<0.01), CK (P<0.01) and BUN (P<0.05) were significantly higher than that of the before transport values. In the case of pH and WHC, the trend was almost similar, with a higher value at zero hour and the decline was drastic in zero to 6 h, followed by 6 to 12 and 12 to 24 h and the control and irradiated samples did not show any significant difference in the decline. Cooking loss of the control and irradiated samples did not have a significant difference at zero hour storage, while the 24h storage brought a significant (P<0.01) increase in cooking loss in all the samples and irradiated samples had a significantly (P<0.05) higher cooking loss at 24h. Shear force values were significantly (P<0.01) less for irradiated samples while storage significantly (P<0.01) increased the values of all the samples. The Hunterlab colour values, L, a, b, C and hue angle, were significantly (P<0.01) higher in irradiated samples at zero hour storage. At 24h storage, the values were significantly (P<0.01) higher than that at zero hour, and only the hue angle values were significantly (P<0.05) higher in irradiated samples. Even though there existed a slight difference between control and irradiated samples in various organoleptic qualities like colour, flavour, juiciness and tenderness, there was no significant difference in overall acceptability between control and irradiated samples. In the present study, the differential response due to irradiation for the stress given to the animals, found to be statistically non significant leading to the result that irradiation conditions did not have an impact on the meat obtained from stressed animal.ThesisItem Open Access Quality and shelf life of low fat restructured turkey meat loaf(Department of Livestock Products Technology, College of Veterinary and Animal Sciences, Mannuthy, 2007) Naseera, A P; KAU; George, T OommenThe health conscious consumers prefer low fat meat products and therefore, the present study was designed to develop a suitable formulary for low fat restructured turkey meat loaf and to assess its physico-chemical and cooking characteristics, sensory qualities, proximate and mineral composition, nutritional value, shelf life and cost of production. Four different formulations, viz., low fat control loaf without fat or fat replacer (LFC), added fat control loaf with 10 per cent sunflower oil added on meat weight basis (AFC), low fat loaf with 0.2 per cent carrageenan (CG) and low fat loaf with 4 per cent nonfat dry milk (NFDM) using skinless lean white and dark turkey meat (2:1), curing ingredients, spices and condiments were prepared. The baked loaves were sliced, packaged aerobically and under vacuum in high density polyethylene and polyamide-polyethylene pouches, respectively. The shelf life of the loaves at 0-4oC for 40 days and -20oC for 60 days were evaluated based on 2-thiobarbituric acid reactive substances value (TBARS), sensory qualities, moisture, protein and fat contents. The pH of the loaves with fat replacers was more (P< 0.05) than the uncooked loaf mix in the range of 5.8-6 and could be considered low acid food. NFDM had the highest (P< 0.05) percentages of 93.29 cooking yield, 65.82 moisture retention (MRP) and 108.7 fat retention (FRP). Carrageenan improved (P< 0.05) the cooking yield and MRP but not FRP. The fat replacers significantly reduced the shear force of the loaves. The percentage of moisture, protein, fat and ash in the mixture of skinless turkey white and dark meat were 75.08, 20.79, 2.11 and 0.95, respectively. The white meat is an excellent source of protein and minerals with the least amount of fat. As the percentage of fat in CG and NFDM were 1.53 and 1.57, respectively they can be labeled as ‘low fat’ as per regulations (<3). Moisture loss on baking was significantly lower for CG and NFDM. but it did not affect other components. The per cent contribution of protein in CG and NFDM to the RDA were 26.21 and 26.83, respectively. Addition of nonfat dry milk significantly increased the percentage of carbohydrate, ash, K, Ca and P and their contribution to RDA. The percentage RDA of calories from fat was 0.63 and 0.64 for CG and NFDM, respectively and below the recommended 30 per cent. The TBARS values of the low fat loaves were lesser than the acceptable range of 1mg malonaldehyde/kg loaf for oxidative rancidity, irrespective of packaging and period of storage. Carrageenan and nonfat dry milk had no significant influence on reducing lipid oxidation. The fat replacers increased the sliceability, flavour, juiciness and overall acceptability of the low fat loaves on day zero but it did not affect the texture, saltiness and mouth coating. NFDM was rated higher for colour, flavor and overall acceptability than CG. The packaging, addition of fat replacers and period of storage at 0-4oC and -20oC for 40 and 60 days, respectively did not affect the appearance, colour, texture and mouth coating. Even though the flavour, juiciness and overall acceptability of the packaged loaves with fat replacers reduced (P< 0.05) on storage, these were moderately acceptable up to 40 and 60 days at 0-4oC and -20oC, respectively. Carrageenan and vacuum packaging enabled in retaining flavour and juiciness on storage. Irrespective of the period of storage and packaging a significant reduction in the moisture and corresponding increase in protein and fat of all loaves was noticed on d 60 of storage at -20oC. The cost of production per kg of CG and NFDM were Rs.167/= and Rs.164/=, respectively. The recipes for a low fat (<2 per cent) restructured turkey loaf with 0.2 per cent carrageenan and 4 per cent nonfat dry milk were developed economically with good overall acceptability, cooking yield, nutritional value and shelf life up to 40 and 60 days at 0-4oC and -20oC, respectively under aerobic and vacuum packaging systems.ThesisItem Open Access Preservation of meat cutlet employing gamma radiation under different packaging systems(Department of Livestock Products Technology, College of Veterinary and Animal Sciences, Mannuthy, 2007) Salke, Dinkar Babanrao; KAU; Kuttinarayanan, P (Guide)Ready-to-fry beef cutlets were prepared in the Department of Livestock Products Technology, College of Veterinary and Animal Science, Mannuthy. They were packaged under aerobic condition in HDPE packets and under vacuum in PA-PE packets. Half number of samples was subjected to irradiation employing gamma irradiation at 2.5 kGy. Samples were stored under room temperature (25-30oC) and in chiller (3-4oC). Samples were analysed for proximate composition on the day of preparation and for pH, TBARS, TV, microbiological and organoleptic qualities on day 0, 5, 10, 15, 20, 30, 45, 60 and 70 of chiller storage. Shelf life of beef cutlet was assessed on the basis of physical signs of spoilage. The nonirradiated samples kept at room temperature were spoiled within 21 h, whereas irradiated sample had the keeping quality of 34-42 h (IRAP and IRVP). In chiller condition the NRAP sample spoiled within 12-15 days, whereas irradiated sample had a shelf life of 50-55 days. The shelf life was 19-22 and 66-71 days in NRVP and IRVP samples, respectively. The proximate composition, Ca and P content were not affected due to irradiation. The pH of the sample was not affected due to irradiation in different treatments, storage and packaging. TBARS and tyrosine value were unaffected by packaging and irradiation, whereas on storage the values were increased. Aerobic plate count, psychrotrophic plate count, yeast and mould count were significantly reduced due to irradiation, while packaging had not shown any significant effect. About 76 per cent reduction in aerobic plate count, 74 per cent reduction in psychrotrophic count and 70 per cent reduction in yeast and mould count was noticed. As storage period enhanced the counts were increased. Since the products are stored under chiller condition the survived bacteria might have been multiplied and count has gone up. The organoleptic qualities were assessed with help of 9 point Hedonic scale. The colour and flavour of the product were unaltered due to irradiation or packaging on the day of preparation. The juiciness and tenderness score had increased due to irradiation with the highest values of tenderness in IRVP samples. The overall acceptability was not affected due to irradiation or packaging on the day of preparation. A gradual decrease in overall acceptability and other score were observed due to storage with IRVP sample scoring the highest. The irradiation preservation of beef cutlet was beneficial for enhancing the keeping quality of beef cutlet under chiller conditions without affecting the qualities. Microbial count like aerobic plate count, psychrotrophic count, yeast and mould count were significantly (P<0.05) reduced due to irradiation at 2.5 kGy, the lowest limit prescribed by PFA. Vacuum packaging of the product combined with irradiation has shown about 25 per cent increase in keeping quality compare to ordinary packaging and 4 times increase compared to nonirradiated samples. Irradiation of the product combined with chiller storage requires less electrical energy for preservation of the product. Considering the extended shelf life, wholesomeness of the product, reduced microbial load and energy saving aspects vacuum packaging followed by irradiation can be advocated as a suitable method for preservation of meat and meat products.ThesisItem Open Access Effect of hurdle technology, chitosan and gamma radiation on quality parameters of chicken fry(Department of Livestock Products Technology, College of Veterinary and Animal Sciences, Mannuthy, 2008) Shijin, A; KAU; Kuttinarayanan, PThe study on the effect of low dose gamma radiation and chitosan coating on shelf-life and quality changes of ready-to-eat chicken fry under vacuum packaging was conducted in the Department of Livestock Products Technology, Mannuthy. Half of the prepared chicken fry was coated with 0.5 per cent chitosan in one per cent glacial acetic acid. The other half was coated with equal quantity one per cent glacial acetic acid. The whole samples were packed under vacuum in PA-PE pouches. Half of the packets from each treatments were irradiated at 2.5 kGy employing Gamma Chamber 5000. Sufficient numbers of packets from each treatment were stored under room temperature (25-30°C) and in chiller (1-4°C). Samples were analysed for proximate composition on the day of preparation and for TBARS, TV, microbiological and organoleptic qualities on day 0, 5, 10, 15, 20, 30, 40, 50, 60 and 70 of chiller storage, while those at room temperature on day 0, 5, 10 and 15 or until spoilage, whichever was earlier. Shelf life of chicken fry was assessed based on the physical signs of spoilage. The spoiled samples were not subjected to any further analysis. The non-irradiated control samples had a shelf life of 5.33±0.23 days at room temperature and 28.16±0.33 days in chiller. The shelf life was extended to 7.33, 8 and 10 days for CH-NIR, IR and CH-IR samples respectively at room temperature. In chiller storage, the samples were consumable up to 67 days (IR) and 73 days (CH-IR). The proximate composition of the product analysed on the day of preparation was not significantly affected due to irradiation or chitosan coating. The TV showed a decreasing trend due to irradiation whereas the TBARS values were increased and it was controlled by chitosan coating. Storage had a significant effect in increasing both these physicochemical qualities. Aerobic plate count, psychrotrophic plate count and yeast and mould count were significantly reduced due to irradiation, chitosan coating and their combination. Whereas the extend of reduction due to chitosan coating alone was not up to the combined effect of chitosan coating and irradiation. As storage period enhanced the counts increased. The increase was rapid in room temperature stored samples and it was slow and steady in chiller samples. As the storage period enhanced, in the chiller stored products, the survived bacteria might have multiplied and count has gone up beyond the initial count as evidenced by the higher count in terminal end of the storage period. The organoleptic qualities were assessed with help of nine point Hedonic scale. The colour, juiciness, tenderness and overall acceptability of the product were improved by irradiation, chitosan coating and their combination. But flavour showed a decrease in score. A gradual decrease in organoleptic qualities was observed due to storage. Even after 60 and 70 days of chiller storage, the samples had an overall acceptability score of above 7 indicating the samples are preferred by the consumers. The cost of chicken fry was Rs. 109.83 per kg and addition of chitosan at a level of 0.5 per cent increased the cost of the same by Rs. 4.38 per kilogram. The irradiation preservation of ready-to-eat chicken fry was beneficial for enhancing the keeping quality of the product under chiller conditions without affecting the qualities. Some of the bad effects of irradiation like increase in fat rancidity can be controlled by the beneficial coating with natural antioxidants like chitosan. Microbial count like aerobic plate count, psychrotrophic count, yeast and mould count were significantly (P<0.05) reduced due to irradiation at 2.5 kGy, the lowest limit prescribed by PFA. The hurdle technology combined with irradiation and chitosan coating has significantly increased the keeping quality of the product. Considering the extended shelf life, wholesomeness of the product, reduced microbial load and energy saving aspects, chitosan coating followed by irradiation can be advocated as a suitable method for preservation of ready-to-eat value added meat products.ThesisItem Open Access Determination of residues of carbofuran and its metabolites in tissues of buffaloes and ducks(Department of Livestock Products Technology, College of Veterinary and Animal Sciences, Mannuthy, 2006) Poulson Joseph; KAU; George T, OommenA research work on the determination of residues of carbofuran and its metabolites in tissues of buffaloes (Bubalus bubalis) and ducks (Anas platyrhynchos) was under taken. The objectives were to develop and standardise a suitable simple method of extraction of residues of carbofuran and its metabolite from meat, liver, kidney and fat of buffaloes and ducks for reversed phase HPLC analysis and to apply this method for further screening of animal tissues for monitoring these residues Fifteen samples of each tissue of buffaloes and ducks were randomly collected from different lots of slaughtered animals in Kerala. Different solvents, viz., acetonitrile (ACN), acetone, methanol, hexane and 2-propanol were used for the extraction of carbofuran residues and its metabolite from tissues. The extracted samples were cleaned up by liquid-liquid partitioning for HPLC analysis using Schimadzu LC-10 AVP series with UV/VIS detector at 211 nm in a mobile phase of acetonitrile (35): water (65). Certified standard references of carbofuran and its metabolites, viz., 3-hydroxy carbofuran, 3-keto carbofuran, 3-hydroxy 7-phenol carbofuran, 3-keto 7-phenol carbofuran and carbofuran phenol were analysed in HPLC to identify the chromatogram peaks of respective compounds. Excellent linearity was observed for carbofuran and 3-hydroxy carbofuran at 1, 10 and 100 ppm. Based on the highest percentage of recovery, ACN was chosen as the best solvent for extraction of residues from meat, liver and kidney and hexane for fat. This solvent system was applied for the extraction of residues in a further HPLC residue monitoring programme in the tissues of buffaloes and ducks. In buffalo meat, liver, kidney and fat the residues of carbofuran and its metabolites could not be detected and hence denoted as below detection limit (BDL). Residues could not be detected in all duck tissue samples, except in one sample, wherein 3-hydroxy carbofuran was detected at 2 ppm and 0.9 ppm in meat and kidney, respectively which is above the MRL. An appropriate method is developed for the screening of animal tissues to detect the presence of residues of carbofuran and its metabolites. This would enable in monitoring and surveillance of residues of carbofuran in animal tissues, hazard analysis and determining the critical control points.ThesisItem Open Access Effect of low dose gamma radiation on the quality of intermediary moisture pet food(Department of Livestock Products Technology, College of Veterinary and Animal Sciences, Mannuthy, 2006) Rana Raj, V R; KAU; Kuttinarayanan, PThe effect of low dose gamma irradiation on the quality of intermediary moisture pet food was assessed in the present study. Dog biscuits were prepared using meat cum bone meal, plain flour (Maida), blood, rendered fat, eggs, wheat bran and black gram flour. The mix was baked at different time temperature combinations to attain three different moisture levels of 10, 15 and 25 per cent. The samples were separately packed in High Density Polyethylene (HDPE) packets at a rate of 200g each and then subjected to gamma irradiation using Gamma Chamber 5000 at various doses of zero, 2.0 kGy, 3.0 kGy, 4.0 kGy, 6.0 kGy and 8.0 kGy. After irradiation the samples were kept in ambient temperature for further analysis like proximate composition, development of rancidity, microbiological quality and palatability/ acceptability attributes on the day of preparation and then on 7, 15, 30, 45, 60, 75, 90, 120, 150 and 180 days of storage or till spoilage which ever was earlier. The proximate compositions of the dog biscuits of all moisture levels were not significantly affected by various doses of irradiation and days of storage. The TBARS values were shown a significant (P<0.05) increase with the increase in the doses of irradiation. The days of storage were also affected the TBARS values significantly (P<0.05). The samples irradiated at 6.0 and 8.0 kGy of all moisture level dog biscuits were spoiled between 120 to 150 days where as the samples irradiated at 4.0 kGy showed a higher shelf life in the absence of any developed rancidity changes. The aerobic plate count was shown a significant reduction as the dose of irradiation increased, also a significant (P<0.05) increase was noticed with the days of storage. In 10 per cent moisture level dog biscuits, the samples irradiated at 6.0 and 8.0 kGy revealed 100 per cent reduction of aerobic organisms, where as the same result was obtained for the samples irradiated at 8.0 kGy in case of 15 per cent moisture level dog biscuits. Coliforms and staphylococcal organisms were present only in 25 per cent moisture level dog biscuits and they were completely destroyed at an irradiation dose of 4.0 kGy and above. All the samples under study were found free from E. coli, Salmonella, Clostridium and faecal streptococcal organisms. The yeast and mould count also showed the same trend as aerobic organisms. The samples of 10 and 15 per cent moisture level dog biscuits were found free from yeast and mould when irradiated at 4.0 kGy and above, while the same result was obtained for 25 per cent moisture level samples on irradiation at 6.0 and 8.0 kGy. The palatability/ acceptability studies were conducted using the dog biscuits of 5, 10, 15 and 25 per cent moisture levels irradiated at 4.0 kGy. The dogs preferred intermediary moisture dog biscuits of 15 and 25 per cent moisture levels when compared with dry dog biscuits having 5 and 10 per cent moisture. It was observed that gamma irradiation of dog biscuits significantly reduced the microbial load with out affecting their proximate compositions. But higher doses of irradiation induced the production of oxidative rancidity. The palatability studies revealed that intermediary moisture level food was more preferred by the dogs than dry food. This study also found that the dog biscuits containing 10 per cent moisture and irradiated at 4.0 kGy had got the highest shelf life of more than 180 days.ThesisItem Open Access Effect of marination and polyphosphate on quality improvement of spent layer meat(Department of Livestock Products Technology (Meat Technology Unit), College of Veterinary and Animal Sciences, Mannuthy, 1997) Anilkumar, M; KAU; Abraham, JSix spent chicken were slaughtered and cut into suitable size, cut up parts were divided into 8 equal parts, two parts were kept as control and the remaining 6 parts were divided into 2 groups and were dipped in 3 per cent STPP solution for 30 minutes and drained, three marinades were prepared containing either curd, lemon juice or tomato pulp. Samples of each group were marinated and kept at 40 C overnight. Parameters such as pH, water holding capacity, weight after marination, weight after overnight chilling, cooking yield and sensory scores were studied after pressure cooking followed by frying and microwave cooking. In this study, it was observed that marination had a significant effect on pH, water holding capacity, cooking yield and organoleptic qualities. The spent chicken meat treated with tomato pulp marinade had the highest score for pH, water holding capacity, cooking yield and organoleptic qualities.ThesisItem Open Access Effect of pork skin collagen as a fat replacer in low fat frankfurter(Department of Livestock Products Technology, College of Veterinary and Animal Sciences, Mannuthy, 2009) Selvakumar, P; KAU; George T OommenThe health conscious meat consumers prefer low fat meat products and therefore, the present study was designed with a view to developing a suitable formulary for low fat frankfurter (LFF) with pork skin collagen (PSC) gel as a fat replacer. Quality was assessed by measuring pH, emulsion stability, cook yield, cook loss, dimensional shrinkage, water holding capacity (WHC), Warner-Bratzler Shear Force Value (WBSFV) , colour by Hunter L*, a*, b* values, proximate composition, nutritive value and organoleptic qualities on the day of production. The shelf life of frankfurters in aerobic (AP) and vacuum packaging (VP) systems at -20oC for 75 days were evaluated based on purge loss, 2-thiobarbituric acid reactive substances value (TBARS), organoleptic qualities, and moisture, protein and fat contents. Six trials of the experiment were conducted and the cost of production was also calculated. Seven different formulations viz., one full fat control 30% with out PSC (30/0) and six treatments 10% low fat with out PSC (10/0), 5% low fat with out PSC (5/0), 10% fat with 5% PSC (10/5), 10% fat with 10% PSC (10/10), 5% fat with 5% PSC (5/5), 5% fat with 10% PSC (5/10) using beef and pork trimmings 1:1, pork skin collagen gel, lard, curing ingredients, spices and condiments were prepared. The steam cooked frankfurters were packaged under AP and VP systems in high density polyethylene and polyamide/polyethylene pouches, respectively and stored at -20oC for 75 days for shelf life studies The pH of the cooked LFF with PSC was significantly more (P< 0.05) than those with out PSC, their uncooked batter and in the range of 6.46-6.55 and could be considered a low acid food. Formulation 10/10 had the highest (P< 0.05) emulsion stability of 87.40, cook yield of 96.28, water holding capacity (WHC) of 95.57 and lowest (P< 0.05) dimensional shrinkage of 1.83 per cent. The WHC of 95.57 of formulation 10/10 was significantly higher (P< 0.05) than in other treatments. The WBSFV of 10/10 was 1.12 kgf, which was significantly lower (P< 0.05) than other treatments indicating its increased tenderness. The PSC significantly reduced the shear force of LFF. The 10/10 formulation had higher L* and b* values of 62.99 and 17.51 and a lower a* value of 5.70. Formulation 10/5 was ranked second among treatments in all these traits. The moisture, protein, fat, carbohydrate and ash contents in 10/5 and 10/10 were 72.32, 13.01, 9.57, 4.17, 0.93 and 71.30, 13.09, 9.82, 4.81 and 0.98, respectively. The per cent contribution of protein to the RDA from 10/10 and 10/5 were 21.82 and 21.68, respectively. The per cent RDA of calories from fat was 4.02 and 3.92, respectively and below the recommended 30 per cent. The purge of 10/10 and 10/5 formulations were significantly lower (P< 0.05) irrespective of the packaging systems and period of storage. The TBARS of low fat formulations with varying levels of PSC were within the acceptable range of 1mg malonaldehyde/kg of frankfurter for oxidative rancidity, irrespective of the packaging systems and storage period. There was no significant increase in the oxidative rancidity of PSC added formulations noticed during the initial 30 days of storage. The appearance, colour, flavour, texture, juiciness, saltiness, mouth coating and overall acceptability of 10/10 were very desirable and comparable with that of full fat control. Formulation 10/10 under VP had a more beneficial effect in retaining flavour, texture, and juiciness followed by formulation 10/5. The period of storage affected the moisture and protein content of 10/5 and 10/10 formulations on d 60 and on d 45 onwards, respectively and packaging systems affected the protein content on d 75 of storage at -20oC. The cost of production calculated per kg of 10/5 and 10/10 were Rs.84/= and Rs.86/= respectively. The formularies for LFF 10/10 and 10/5 were developed with very acceptable organoleptic attributes, cook yield and shelf life up to 75 days at -20oC, respectively under AP and VP systems economically. The contribution of calories from fat to the Recommended Daily Allowance (RDA) was below the recommended 30% in all frankfurter formulations making the product acceptable to health conscious consumers. The cost of production was calculated on laboratory scale and further investigations with large quantity are required for commercial production at industrial level.