Native desi chickens were procured from local farmers and were individually weighed after overnight fasting (except for water) and then slaughtered. The native desi chickens were killed by cutting the jugular vein and carotid artery on one side of the neck near atlanto-occipital joint. After bleeding the carcasses were scalded at 55 ± 2°C for 1min, handpicked and manually eviscerated. The meat separated from the carcasses and meat was cut into small cubes (1 cm × 1 cm × 1 cm). The desi chicken meat cubes were used for preparation of pickle.

The formula for native desi chicken meat pickle was developed after conducting a series of preliminary trials. The ingredients used in the preparation of desi chicken meat pickle are presented in Table 1.

The spices and condiments mix were prepare by using dry spices viz. aniseed (10%), black pepper (10%), capsicum (8%) caraway seed (10%), cardamoms (5%), cinnamon (4%), cloves (1%), coriander (20%), cumin seed (22%) and turmeric (10%) were cleaned to remove the extraneous materials and dried in oven at 50 °C for 4 h. The ingredients were ground in a grinder and sieved through a fine mesh. For preparation of condiments mix, fresh garlic and ginger were procured from the local market and were peeled of the external covering. The required quantities were cut into small bits and mixed in a laboratory blender to a fine paste.

The native desi chicken meat cubes were mixed with turmeric powder and marinated for 1 h at 5 ±2 °C for uniform dispersion. Then the native desi chicken meat pieces were pressure cooked at 15 psi for 10 min and then used for preparation of pickle. The pressure cooked native desi chicken meat pieces were deep fried in heated gingili oil till golden brown colour appeared and were kept separately. The mustard seeds, condiments mix, roasted fenugreek powder, roasted cumin powder, asafetida powder, red chilli powder and spice mix were shallow fried in the remaining gingili oil to get the “golden brown stage”. Salt and fried native desi chicken meat pieces was added to it and allowed to boil for two min. Then, vinegar was added to make a broth and heated with high constant stirring till boiling started. The native desi chicken meat pickles were allowed to cool to room temperature. After cooling the native desi chicken meat pickle were packed in the polyethylene terephthalate (PET) 250 gm bottles and stored at 32 ± 5 °C. Likewise four batches of native desi chicken meat pickle were prepared. The pickle were evaluated the various physico-chemical parameters, microbial profile and sensory attributes on a 9 - point hedonic scale at an interval of 0, 15, 30, 45, 60, 75 and 90 days of storage at room temperature (32 ± 5 °C).

The pH native desi chicken meat pickle was determined by using digital pH meter. Moisture contents of the products were determined as per AOAC (1995). Procedure of APHA (1984) was used for estimation of titrable acidity (% acetic acid). Fee fatty acids (as % oleic acid) were determined as per procedures outlined by AOAC (1995). The procedure of Witte et al. (1970) was followed to estimation thiobarbituric acid value (TBA).

Total plate, coliform, yeast and mold and staphylococcal counts of stored native desi chicken meat pickle samples were determined by the methods described by APHA (1984). Readymade media (Hi-media Laboratory Pvt. Ltd., Mumbai, India) used for enumeration of microbes. Preparation of samples and serial dilutions were done near the flame in a horizontal laminar flow apparatus which was pre-sterilized by ultraviolet irradiation by observing all possible aseptic precautions. 10 fold dilutions of each sample were prepared aseptically by blending 10 gm of sample with 10 ml of 0.1% sterile peptone water with a pre sterilized blender. Plating medium was prepared by dissolving 23.5 g of plate count agar in 1 lit of distilled water and pH was adjusted to 7.0 ± 0.2. Media was autoclaved at 15 1b pressure for 15 min before plating. The plates were incubated at 30±1 °C for 48 hr for total plate count. Coliform count was detected using 41.5 g of Violet Red Bile Agar and plates were incubated at 37 ± 1° C for 48 hr. 60.5 gm of Potato Dextrose Agar was used for enumeration of yeast and mold count and the plates were incubated at 25 ± 1°C for 5 days. Staphylococcal count was deducted by using 63.2 g Baird Parker Agar was dissolved in 950 ml of distilled water. The pH was adjusted to 7.0 ± 0.2 and sterilized before plating. The medium was tempered to 50 °C and egg yolk tellurite emulsion was added to the medium. 1 ml of suitable dilutions were placed in sterile petridish and overlaid with molten agar. After solidification, the plates were incubated at 37 °C for 48 hr. Following incubation, plates showing 30- 300 colonies were counted. The average number of colonies for each species was expressed as log₁₀ cfu / gm sample.

Sensory evaluation was conducted with experienced panelists. Native desi chicken meat pickle was served to the panelists. The sensory attributes like appearance and colour, flavour, juiciness, saltiness, sourness and overall palatability were evaluated on 9 - point descriptive scale (where in 1 - is extremely undesirable and 9- is extremely desirable) as suggested by Keeton (1983).

The mean values for changes in physico-chemical characteristics of native desi chicken meat pickle during storage are presented in Table 2. The overall days mean showed a non significant increase in pH with increasing storage period up to 90 days. The pH values of native desi chicken meat pickle were below 5.0 up to 60 days of storage which is considered to be critical for storage stability of picked products (Dziezak, 1986). However, overall days mean for native desi chicken meat pickle pH non significantly increased above 5.0 on day 75 to 90 during storage. Similar increasing in pH with increasing storage period of various meat pickles were also reported earlier (Nayak et al., 2011; Bhusal et al., 2017; Khade et al., 2019). It is believed that hydrolysis of the proteins molecules could have released amino group and could have increased the pH in the later period (Webster et al., 1982). Moisture content of native desi chicken meat pickle values were significantly (P<0.05) decreased gradually during entire period of storage. However, no significant difference in overall day’s means for moisture content was observed between days 0 to15 and 45 to 60 of storage. A significant and progressive decrease in moisture in native desi chicken meat pickle might be due to evaporation of water during sampling where the native desi chicken meat pickle samples drawn from the same PET bottle over the entire period of storage and could have resulted in more loss of moisture in native desi chicken meat pickle. A non significantly increased in titrable acidity values of native desi chicken meat pickle were observed with increasing storage period this might be due to more loss of moisture in native desi chicken meat pickle which in turn could have increased concentration of undissociated molecules of acetic acid which increase the titrable acidity (Khade et al., 2019). The present results are in conformity with Jayanthi et al. (2008) and Pal and Agnihotri (1994) who reported titrable acidity of pickle increased non significantly with advancement of storage period. Free fatty acids values of native desi chicken meat pickle increased non - significantly with increasing storage period. The increase in free fatty acid value in native desi chicken meat pickle might be due to bio chemical and microbial spoilage. The present results are similar with those of Jayanthi et al. (2008) who reported free fatty acids values were increased with increasing storage period in spent hen chicken meat pickle.A significant (p<0.05) and progressive increase in TBA value was observed with increase in storage period and the value did not statistically different between days 0 to 60 and 75 to 90 of storage. The TBA values in native desi chicken meat pickle was increased from 0.57 to 1.98 mg malonaldehyde / kg of meat pickle during the storage period but the values remained well within the threshold limit of 1-2mg malonaldehyde / kg of meat product during the entire storage. Increase in the TBA value might be due to the oxidation of fat during storage period (Pal and Agnihotri, 1994). Increase of microbial load in meat samples could have caused increased oxidative changes. These oxidative changes might also be attributed to increase in TBA value (Jay, 1996).

The mean values for changes in microbial profile of native desi chicken meat pickle during storage are presented in Table 2. Total plate and yeast and mold counts were increased with increasing storage period. However, no significant difference (p<0.05) in total plate and yeast and mold counts were observed between days 0 to 60 of storage. Coliform and staphylococcal counts did not deducted between 0 to 60 days of storage and the counts were increased nonsignificantly between 60 to 90 days of storage. In our present study, the native desi chicken meat pickle did not show any symptoms of spoilage or off odour on throughout storage period. Higher acidity, salt content, cooking, frying and low moisture reduces the microbial load of the product (Gadekar et al., 2010). Similar observations also made by Pal and Agnihotri (1994) in chevon meat pickle and Khade et al. (2019) in spent hen meat pickle. During the storage period, the microbiological quality of native desi chicken meat pickle was satisfactory for throughout storage period and the microbial counts where within in the range of 0.82 to 2.90 log₁₀ cfu / gm sample (Jay, 1996).

*Number of observations: 4

Means bearing same superscripts row-wise do not differ significantly (p<0.05).

**Number of observations: 4

Means bearing same superscripts row-wise do not differ significantly (p<0.05).

***Number of observations = 32.

Sensory attributes were evaluated on a 9-point descriptive scale (wherein, 1 = extremely undesirable; 9 = extremely desirable).

Means bearing same superscripts (lowercase letters) row-wise do not differ significantly (p< 0.05).

The mean values for changes sensory attributes of native desi chicken meat pickle during storage are presented in Table 4. The sensory attributes scores for appearance and colour, flavour, juiciness, saltiness, sourness and overall acceptability were decreased with increasing storage period. All the sensory attributes of native chicken meat pickle were statistically un affected between 0 to 60 days of storage and scores decreased significantly (p<0.05) on day 75 of the storage. Decrease in overall acceptability scores with increasing storage period might be due to decrease in appearance and colour, flavour, juiciness saltiness and sourness scores. The possible reason for decrease in appearance and colour scores during refrigerated storage might be due to lipid oxidation. Flavour reduction during storage might be due to microbial growth and lipid oxidation (Tarladgis et al., 1960). Dehydration and moisture reduction of the product with advancement of storage could be the reason for lower juiciness scores. Similar observations of decrease in overall acceptability of various meat pickles with increasing storage periods were also reported (Khade et al., (2019), Jayanthi et al. (2008) and Pal and Agnihotri, 1994). The native desi chicken meat pickle remained highly acceptable up to 60 days of storage and thereafter between 60 to 90 days of storage the native desi chicken meat pickle was only moderately acceptable.