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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 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.ThesisItem Open Access Effectt of curry leaves (murraya sp.) and peppermint (mentha sp.) plate on shelf life irradiated chicken tikka(Department of Livestock Products Technology, College of Veterinary and Animal Sciences, Mannuthy, 2009) Ahire Girish, Sureshrao; KAU; Kuttinarayanan, PTo study the beneficial effects of irradiation, application of curry leaves (Murraya sp.) and peppermint (Mentha sp.) paste in the marinade of chicken tikka, the present study was conducted at Department of Livestock Products Technology, College of Veterinary and Animal Sciences, Mannuthy. Chicken tikka was prepared incorporating zero per cent, 1.0% CL, 1.0% PL or both and it was fried separately. After cooling, tikka was packed in HDPE (50µ) packets. Half of the packets in each treatment group were subjected to irradiation at 2.5 kGy using Gamma Chamber 5000 and stored at chiller temperature (1–40C). The irradiated and non-irradiated chicken tikka of various treatment groups under chiller storage were analysed for different quality parameters viz., physical, physicochemical, microbiological analysis and organoleptic evaluation on the day of preparation and on days 5, 10, 15, 20, 25, 30, 45 and 60 or until spoilage whichever was earlier. The samples were subjected to proximate analysis on the day of preparation. Shelf life of chicken tikka was assessed based on the physical signs of spoilage. The non-irradiated control samples had a shelf life of 27-30 days in chiller storage. Application of CL, PL and both had extended the shelf life of the product by 3-4 days, 7-8 days and nearly 5 days respectively. Irradiated samples had approximately two times shelf life than that of non-irradiated samples in all treatment groups under chiller storage. The C-IR and PL-IR samples had storage life of 61-63 days and 68-70 days respectively in chiller storage. Irradiation did not significantly affect any of the proximate composition. Moisture, fat and protein were significantly affected by application of CL, PL and their combination. The highest energy content of 255.40±2.79 kcal/100g was recorded in PL-IR group. The pH of chicken tikka samples did not show any significant difference due to irradiation in different treatment groups on the day of preparation. As storage period enhanced pH had significantly (P<0.05) reduced in all treatment groups except in CL-NR and CL-IR groups where, pH had significantly (P<0.05) increased. The TBARS values were non significantly increased due to irradiation on the day of preparation in various treatment groups. Addition of CL, PL and CLPL alone in the marinade had a beneficial effect in reducing the TBARS compared to control samples in both NR and IR groups. TV showed decreasing trend due to irradiation as well as application of CL, PL and CLPL. Storage had significant (P<0.05) effect in increasing both these physicochemical properties. Aerobic plate count, Psychrotrophic count and yeast and mould count were significantly (P<0.05) reduced due to irradiation and combination of irradiation with CL, PL and CLPL. Whereas, extend of reduction due to application of CL, CLPL alone was not up to the level of PL alone to non-irradiated groups. PL-IR samples had recorded the lowest counts among all treatment groups throughout the storage period. As storage period enhanced the counts were significantly (P<0.05) increased. 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 as well as addition of CL, PL and CLPL. A gradual decrease in organoleptic qualities was observed only after 5th day of storage in most of the samples. Even on 60th day of chiller storage, the samples had an overall acceptability score of above 7 indicating the samples are preferred by the consumers. The cost of production was Rs. 122.30, Rs. 123.30, Rs. 125.30 and Rs. 126.30 per kg for the control, CL, PL and CLPL treatment groups respectively. Irradiation of ready-to-eat chicken tikka was beneficial for enhancing the keeping quality of the product under chilling condition without affecting qualities. Addition of herbal pastes containing natural antioxidants in the marinade for the preparation of chicken tikka was found to be beneficial in reducing many of undesirable effects. Among the herbal pastes viz., peppermint paste, curry leaf paste and their combination, it was found that peppermint paste had better effect than the other two. The microbial counts were significantly (P<0.05) reduced due to irradiation at 2.5 kGy, the lowest limit prescribed by PFA. Considering extended shelf life, wholesomeness of the product, reducing the microbial load and energy saving aspects, preparation of chicken tikka incorporating peppermint paste in the marinade and followed by irradiation can be advocated as a suitable method for preparation of ready-to-eat value added meat products.ThesisItem Open Access Quality analysis of dried beef and standardization to suit the local market(College of Veterinary and Animal Sciences, Mannuthy, 2010) Rani, Chacko; KAU; Kuttinarayanan, PSmoked dried meat of cattle and buffalo are very popular in hilly areas and a sought after product. In order to assess the quality, method of preparation and consumption pattern, a survey was conducted at 100 households in Adimaly Gramapanchayat, Idukki district, Kerala. It was revealed that ninety eight per cent of people had consumed the product, smoking is the preferred method over sun drying and eighty per cent of the people prepared the product at their home. Twenty five samples were collected and were divided according to the method of preparation. On assessment of chemical composition, physicochemical qualities and microbiological qualities, the moisture, fat, protein, ash, energy, sodium chloride content, pH, TBARS, TV and Rehydration ratio varied non significantly and acid insoluble ash and carbohydrate content, aerobic plate count and yeast and mould count varied significantly between samples prepared by different methods. Unhygienic preparation practices shortened the shelf life of the product but nevertheless the product had a great demand. Six batches of meat were procured from the animal slaughtered at Department of Livestock Products Technology. Half of the sample was rubbed with salt (10%), powdered pepper (1.0%) and turmeric (0.5%) and to the other half chitosan (1.0%) was incorporated in excess of above ingredients. Cured meat samples were subjected to smoking and drying in the smoke house. The temperature and relative humidity of the smoke house were recorded. Both the smoked samples were packed separately in HDPE (aerobic) and PAPE (vacuum). Half of the sample from each group were subjected to gamma irradiation at 2.5 kGy and stored at ambient temperature. The proximate composition of the sample was analysed on day of preparation and other quality parameters were assessed on days 5, 10, 15, 20, 25, 30, 45, 60 and 75 or until spoilage which was detected by the physical signs of spoilage. The irradiated sample had an extended shelf life of 79-83 days compared to non irradiated sample which had a storage life of 27-29 days. Maximum storage life was noticed in chitosan applied smoked dried beef, placed in vacuum and irradiated at 2.5kGy.Chitosan addition improved yield, reduced drip loss and changed proximate composition. By the addition of one per cent chitosan, there was about five per cent higher yield without altering shelf life and content of moisture, fat, protein, ash, carbohydrate and sodium chloride content were significantly changed.Irradiation did not alter the rehydration capacity but chitosan application decreased it. Addition of chitosan showed a higher pH on the day of preparation. Addition of chitosan and irradiation reduced tyrosine value. Irradiation and non addition of chitosan individually or in combination increased TBARS values. Aerobic plate count and yeast and mould count were significantly reduced due to irradiation alone and in combination with chitosan. The pH, TV,TBARS and microbial load increased due to storage.The organoleptic qualities like colour, flavour, juiciness, tenderness and overall acceptability of the product were improved by irradiation initially and reduced on storage in all samples. Chitosan added and vacuum packaged product showed higher scores compared to control. The cost of control sample was Rs. 268.18 per Kg and in the case of chitosan incorporated samples it was Rs. 252.35 per Kg.Irradiation in combination with different hurdles like addition of chitosan, vacuum packaging can be recommended for the production of shelf stable smoked dried beef and can be marketed without much quality change since the product has a great demand.