Effect of jackfruit supplement and ageing on the Physico-chemical, texture and sensory characteristics of Chevon patties

Abstract

The study was conducted to evaluate the suitability of using immature jackfruit and chevon meat in emulsion-based products preparation and to assess their quality during refrigerated storage. Chevon meat patties (treatments T2, T3 and T4) were prepared in which chevon meat was substituted with 10%, 20% and 30% immature jackfruit and compared with patties from chevon meat (control T1). The addition of jackfruit in chevon meat patties overall significantly (P < 0.05) influenced proximate analysis, physico-chemical characteristics, textural profile, microbiological profile and sensory scores of the products. Results also showed significant (P < 0.05) effect of jackfruits on storage qualities of the chevon meat patties under refrigerated storage (4°C ± 1°C) for about nine days. The patties remained stable with minor changes in physico-chemical, microbiological and sensory quality during refrigerated storage for nine days. Hence chevon meat and immature jackfruit effectively be utilized in developing patties.

Keywords:

• chevon patties
• jackfruit
• texture analysis
• qualities
• storage studies

1. Introduction

Jackfruit (Artocarpus heterophyllus Lam) is a large fruit of a milky-juice tree and it belongs to the family Moraceae. Jackfruit is one of the biggest edible fruit in the world, and its pulpy part represents the parianth (Naik 1949; Sturrock 1959). It originated in the forests of the Western Ghats (India), where it still grows in the wild, as well as in the evergreen forests of Assam and Myanmar. It is cultivated throughout Bangladesh, Burma, India, Indonesia, Malaysia, the Philippines, Sri Lanka and Thailand and to some extent in Brazil and Queensland (Australia). The poor people of jackfruit growing area used to eat this fruit regularly in their daily meals. It is commonly referred to as ‘the poor man’s food’ (Rahman et al. 1995). Jackfruit occurs naturally in two textural forms: Ghila with soft and pulpy perianth when ripe and Khaja with firm perianth (Rahman et al. 1999). Additionally there is another type named Dorasha having both the characteristics of Khaja and Ghila. Jackfruit has been reported to contain high levels of protein, starch, calcium and thiamine (Brukill 1997). The juicy pulp of the ripe fruit is eaten fresh as a dessert. The bulbs (excluding the seeds) are rich in sugar, fairly well in carotene and also contain vitamin C (Bhatia et al. 1955). Jackfruit is also rich in nutrients such as sodium, potassium, iron, vitamin B6, calcium, zinc and many other nutrients (Goswami et al. 2011). Jackfruit can lower blood pressure, cure fever and diarrhoea (Goswami et al. 2011). This fruit is also known to be beneficial in asthma, ulcers, indigestion, tension, nervousness and constipation. It can slow down ageing and cell degeneration. Jams, beverages, candies, conserves and dehydrated forms are other industrial uses for which the jackfruit can be utilized (Naik 1949).

Chevon is red meat that is often viewed as potential competitor to beef and sheep meat. It is almost universally acceptable and free from culture, tradition, social and economic conditions (Webb et al. 2005; Argüello 2011; Xazela et al. 2011). A cross-culture education ethnic study in multicultural South Africa considered the goat meat for cultural activities (Mahanjana & Cronje 2000). According to Simela et al. (2008) and Kadim and Mahgoub (2012), chevon and chevon products are considered as high quality products on sensory evaluation by the trained panellists. Chevon has also been reported to contain higher collagen and has lower solubility than mutton and its intramuscular connective tissues remain unchanged during post-mortem ageing (Kannan et al. 2005). Keeping in view of easy availability, medicinal and nutritional qualities the jackfruit was incorporated to know its suitability for emulsion types meat products like chevon patties.

2. Materials and methods

Chevon was purchased from authorized slaughter house, Mathura, UP, India. Trimming and deboning were done in the Department of Livestock Products Technology, DUVASU Mathura, UP, India. Then the meat was minced twice using 6 mm and 4 mm plate in meat mincer (Sciencetech® TSM#8, Factory model LW-6118A-8). Jackfruit was purchased from local market, Mathura. After removal of outer hard covering and chopping into small pieces, it was then minced in meat mincer using 6 mm and 4 mm plates twice to make a fine paste. Other ingredients used in the study such as condiments, salt, refined oil, spice mix, phosphate and oil were also purchased from local market Mathura, UP, India.

2.1. Methodology for preparation of patties

Chevon patties were prepared using the ingredients shown in Table 1. Initially four types of the emulsions were prepared using various combinations of chevon, refined wheat flour and jack fruit. In first group (T1) jackfruit was not used whereas, in other combinations chevon was replaced with jackfruit in a ratio of 10% (T2), 20% (T3) and 30% (T4) weight by weight. The salt was added first to the meat and mixed using bowl chopper for 2 minutes, then the jackfruit was added and mixed for another 2 minutes. After that refined wheat flour was added and bowl chopper was run for 2 minutes. Finally the condiment, spices, fat, phosphate and ice water were added in treatment groups and mix was run for about 2 minutes. In control, jackfruit was not added but rest of the process remained same as of treated products. After emulsion preparation patties were made manually and raw patties were cooked in micro-oven (LG Pvt. Ltd.). One side of the patties was cooked at 200°C for 20 minutes and then the other side cooked for 10 minutes. By this way the internal temperature of patties (75°C ± 1°C) was reached. Finally, these cooked patties were stored under refrigeration for further study.

Table 1. Formulation for preparation of chevon patties using jackfruit.

Ingredients (% w/w)	Control (T1)	Treatment (T2)	Treatment (T3)	Treatment (T4)
Goat meat	76.00	68.40	60.80	53.20
Jackfruit	0.00	7.60	15.20	22.80
Condiments	3.0	3.0	3.0	3.00
Salt	1.5	1.5	1.5	1.50
Phosphate	0.30	0.30	0.30	0.30
Refined wheat flour	3.00	3.00	3.00	3.00
Spices mix.	2.0	2.0	2.0	2.00
Fat	5.00	5.00	5.00	5.00
Ice water	9.20	9.20	9.20	9.20
Total	100.00	100.00	100.00	100.00

2.2. Proximate analysis

Moisture, protein, fat and ash content of the patties were determined by using standard procedure (AOAC 2000).

2.3. Physico-chemical analysis

Cooking yield was determined by measuring the difference in the sample weight before and after cooking (Murphy et al. 1975). Moisture retention value (the amount of moisture retained in the cooked product per 100 g of sample) was determined according to the equation of El-Magoli et al. (1996). It was calculated by multiplication of cooking yield with moisture in cooked chevon patties divided by 100. Percent diameter reduction was calculated using difference of raw chevon patties diameter and cooked chevon patties diameters divided by raw chevon patties diameter and multiply with 100. The pH of chevon patties was determined by the method of Trout et al. (1992) using a digital meter (Systronics Digital pH Meter 803).

2.4. Texture profile analysis (TPA)

TPA of chevon patties incorporated with jackfruit was performed with a texture analyser TA-XT2 (Stable Micro Systems, Surrey, UK) following the procedures of Bourne 1978 in Goat Products Technology Laboratory at Central Institute for Research on Goat, Makhdoom, Mathura, UP, India. For texture analysis chevon patties were cut into uniform cubic size (1.5 cm × 1.5 cm × 0.5 cm). For the TPA, samples were compressed to 60% of their original height. Texture profile parameters such as hardness, adhesiveness, cohesiveness, springiness chewiness and gumminess were determined and interpreted following descriptions provided by Bourne 1978. During TPA, pretest speed was 2 mm/s, test speed was 3 mm/s, post test speed was 3 mm/s, distance was 10 mm and exposure time was 5 s.

2.5. Sensory evaluation

Thirty members of the panel were trained on product descriptions and terminology. The sensory evaluation was done on a seven-point scale (Carpenter et al. 2000). For sensory evaluation, chevon patties were cooked until golden brown colour appears and served warm to an experienced panel of scientists and postgraduate students in the discipline of Livestock Products Technology, DUVASU, Mathura. The sensory attributes evaluated were colour, appearance, odour, taste, gumminess, hardness, juiciness and overall acceptability.

2.6. Statistical analysis

Data obtained in the study were analyzed statistically on ‘SPSS-16.0’ software package as per standard methods (Snedecor & Cochran 1994). Duplicate samples were drawn for each parameter and the experiment was replicated thrice (n = 6). Sensory evaluation was performed by a panel of six member judges three times, so total observations being 18 (n = 18). Data were subjected to one-way analysis of variance and level of significance among the treatments and two-way analysis of variance and level of significance in case of storage study.

2.7. Microbial analysis

Total viable count (TVC), yeast and mould count in patties sample was determined as per the method described by APHA (1984).

3. Results and discussion

3.1. Proximate analysis

The proximate analysis values are presented in Table 2. The moisture content in chevon patties was in the range of 55.59 ± 0.73 to 62.47 ± 0.42 percent. The overall increase in the moisture content was significant (P < 0.05) with an increase in level of jackfruit in chevon patties. That might be due to higher moisture content in immature jackfruit. Arkroyd et al. (1966), Gunasena et al. (1996), Azad (2000) reported the moisture content of edible part of immature jackfruit in the range of 76.20–85.20%. Percent protein, fat and ash decreased significantly (P < 0.05) with an increasing level of jackfruit. The decreased protein content in patties might be due to the less protein in immature jackfruit as compared to the goat meat. Hedrick et al. (1994) reported 19.50% protein in chevon while jack fruit contains protein in the range of 2.0–2.6% (Arkroyd et al. 1966; Gunasena et al. 1996; Azad 2000). Hedrick et al. (1994) reported 1.5% ash in lamb meat as compared to 1.1% in immature jackfruit (Hossain & Haque 1979; Karim et al. 2008). The reason may be less mineral content in immature jackfruit in comparison to chevon. Decreased fat content in patties might be due to the low fat content in immature jackfruit. Arkroyd et al. (1966), Hedrick et al. (1994), Gunasena et al. (1996), Azad (2000) reported 7.0% fat in the goat meat while immature jackfruit contains only 0.1–0.6% fat.

Table 2. Proximate and physico-chemical properties of chevon patties incorporated with jackfruit (mean ± SEM).

Proximate composition of chevon patties incorporated with jackfruit (mean ± SEM)
Sample	Moisture	Protein	Fat	Ash
T1	55.59^d ± 0.73	22.23^a ± 0.47	13.95^a ± 0.34	2.22^a ± 0.01
T2	58.02^c ± 0.49	18.39^b ± 0.39	11.65^b ± 0.33	2.08^b ± 0.008
T3	60.06^b ± 0.50	15.44^c ± 0.41	9.63^c ± 0.31	1.93^c ± 0.03
T4	62.47^a ± 0.42	9.90^d ± 0.17	6.88^d ± 0.26	1.84^d ± 0.014
Physico-chemical parameters of chevon patties incorporated with jackfruit (mean ± SEM)
	Moisture:protein ratio	Decrease indiameter	Moisture retention	Yield
T1	2.51^a ± 0.07	26.34^a ± 0.50	36.51^b ± 0.53	65.68^a ± 0.60
T2	3.16^c ± 0.07	20.60^c ± 0.54	41.82^a ± 0.42	72.08^c ± 0.76
T3	3.81^b ± 0.06	22.73^b ± 0.61	41.04^a ± 0.65	67.90^b ± 0.61
T4	6.32^a ± 0.10	24.49^b ± 0.72	40.58^a ± 0.43	64.98^a ± 0.85

Note: Superscripts bearing different alphabets row wise differ significantly (P < 0.05).

T1, control; T2, 10% replacement of meat by jackfruit; T3, 20% replacement of meat by jackfruit; T4, 30% replacement of meat by jackfruit.

3.2. Physico-chemical analysis

Various physico-chemical qualities namely moisture protein ratio, decrease in diameter, moisture retention and cooking yield of goat patties are given in Table 2.

The mean values of cooking yield ranged from 65.68 ± 0.60% to 64.98 ± 0.85%. Cooking yield increased significantly (P < 0.05) in control (T1), T2 and T3 patties and decreased in T4. Increased cooking yield might be due to the water retention properties of the fibre (Confrades et al. 2000; Garcia et al. 2002). Arkroyd et al. (1966), Gunasena et al. (1996), Azad (2000) reported 2.6–3.6% fibre in immature jackfruit. Moisture retention values were lowest in the control than in other groups. The highest mean value of moisture retention was in T2 group. Percent moisture retention did not differ significantly among T2, T3 and T4. Moisture protein ratio increased significantly (P < 0.05) from T1 to T4 and range was 2.51 ± 0.07 to 6.32 ± 0.10. Increased moisture protein ratio might be due to higher moisture content in jackfruit as compared to goat meat. Decrease in diameter was in the range of 20.60 ± 0.54% to 26.34 ± 0.50%. Maximum decrease in diameter value was observed in T1 and minimum in T2 group.

3.3. Texture profile analysis

Effects of immature jackfruit addition on textural properties of chevon patties are shown in Table 3. Generally, all textural attributes investigated were influenced by immature jackfruit incorporation, except adhesiveness.

Table 3. TPA of chevon patties incorporated with selected levels of immature jackfruit (mean ± SEM).

Sample	Hardness (N/cm^2)	Adhesiveness (Ns)	Springiness (cm)	Cohesiveness (ratio)	Gumminess (N/cm^2)	Chewiness (N/cm)
T1	25.93^a ± 0.73	0.01^a ± 0.001	0.86^a ± 0.02	0.55^a ± 0.04	14.50^a ± 0.42	11.72^a ± 0.36
T2	20.27^b ± 0.73	0.02^a ± 0.002	0.72^b ± 0.03	0.49^a ± 0.03	8.30^b ± 0.54	5.77^b ± 0.35
T3	20.02^b ± 0.82	0.06^b ± 0.005	0.71^b ± 0.01	0.38^b ± 0.01	7.29^cb ± 0.28	5.08^cb ± 0.31
T4	16.80^c ± 0.85	0.07^c ± 0.007	0.66^b ± 0.02	0.37^b ± 0.01	7.07^c ± 0.16	4.62^c ± 0.16

Note: Superscripts bearing different alphabets row wise differ significantly (P < 0.05).

T1, control; T2, 10% replacement of meat by jackfruit; T3, 20% replacement of meat by jackfruit; T4, 30% replacement of meat by jackfruit.

Hardness of chevon patties decreased proportionately with the level of enhancement of immature jackfruit. Immature jackfruit-based patties recorded hardness in the range of 16.80 ± 0.85 to 20.27 ± 0.73 N/cm² which was significantly lower (P < 0.05) than control patties (25.93 ± 0.73 N/cm²). Reduction in hardness value might be due to more moisture with immature jackfruit. This hardness reduction could be attributed to the higher moisture content of fresh oyster mushroom in meat protein systems (Kotwaliwale et al. 2007). Several authors have reported that the dilution effect of non-meat ingredients in meat protein systems primarily accounted for soft texture (Comer & Dempster 1981; Tsai et al. 1998). The adhesiveness value increased significantly (P < 0.05) as the level of the immature jackfruit increased in chevon patties. The adhesiveness value was in the range of 0.01 ± 0.001 to 0.07 ± 0.007 Ns. The minimum adhesiveness value occurred in control and maximum in chevon patties having 30% immature jackfruit. A significantly (P < 0.05) lower value for springiness was observed in chevon patties having immature jackfruit as compared to control. The springiness value ranged from 0.66 ± 0.02 to 0.86 ± 0.02 cm. Highest values (0.86 ± 0.02 cm) were recorded in control and lowest (0.66 ± 0.02 cm) in chevon patties containing 30% immature jackfruit. The springiness value did not differ (P > 0.05) significantly among immature jackfruit-treated chevon patties. The cooking process of patties added with immature jackfruit could lead to some modifications in their structure, which could cause decrease in the springiness of the patties on addition of higher concentration. Cohesiveness of chevon patties was increased proportionately with the level of immature jackfruit added. Chevon patties prepared without immature jackfruit (control) were less cohesive (0.01 ± 0.001 cm/cm) as compared to chevon patties prepared with 10% (0.02 ± 0.002 cm/cm), 20% (0.06 ± 0.005 cm/cm) and 30% (0.07 ± 0.007 cm/cm) jackfruit, respectively. Additions of immature jackfruit in chevon patties reduce the gumminess. Chevon patties formulated with 10%, 20% and 30% immature jackfruit were less gummy than the control. In this order gumminess in the patties was 8.30 ± 0.54, 7.29 ± 0.28 and 7.07 ± 0.16 N/cm², respectively, and was significantly (P < 0.05) lower than the control (14.50 ± 0.42 N/cm²). Incorporation of immature jackfruit in chevon patties also reduced the chewiness. These values in patties containing 10, 20 and 30% immature jackfruit were 5.77 ± 0.35, 5.08 ± 0.31 and 4.62 ± 0.16 N/cm which were significantly lower than the control (11.72 ± 0.36 N/cm).

3.4. Ageing stability of chevon patties

The mean values of pH of the patties determined after 0, 3, 6 and 9 days of ageing are presented in Table 4. The pH values of treatments were slightly higher than control it may be due to lower pH 5.67 value of goat meat (Kadim et al. 2008). The pH increased significantly (P < 0.05) from day 0 to day 6 and decreased on the nineth day of storage. The significant (P < 0.05) differences in pH observed between 0–9 days of storage under refrigeration. However, Sunki et al. (1978) reported no significant change in pH of ground meat and meat products on storage at refrigeration temperature up to 7 days. The reduction in pH after 6 days of refrigeration storage might be due to growth of psychrophilic gram-positive bacteria especially lactic acid bacteria as reported by Shelef (1975).

Table 4. Change in pH, TBARS and FFA during storage of chevon patties prepared using jackfruit under aerobic storage at 4°C ± 2°C (mean ± SEM).

Sample	0 day	3 days	6 days	9 days
pH
T1	6.25^cB ± 0.005	6.31^bB ± 0.005	6.41^aC ± 0.01	6.16^d ± 0.02
T2	6.27^cB ± 0.008	6.33^bB ± 0.009	6.44^aCB ± 0.01	6.18^d ± 0.01
T3	6.36^bA ± 0.03	6.41^bA ± 0.01	6.48^aBA ± 0.02	6.17^c ± 01
T4	6.39^bA ± 0.03	6.44^bA ± 0.02	6.51^aA ± 0.02	6.20^c ± 0.01
TBARS (mg/kg malonaldihyde)
T1	0.138^dA ± 0.001	0.151^cA ± 0.001	0.159^bA ± 0.001	0.169^aA ± 0.001
T2	0.135^dB ± 0.001	0.144^cB ± 0.001	0.154^bB ± 0.001	0.163^aB ± 0.001
T3	0.132^dC ± 0.001	0.145^cB ± 0.001	0.154^bB ± 0.002	0.160^aC ± 0.001
T4	0.129^dD− ± 0.001	0.140^cC ± 0.001	0.151^bB ± 0.001	0.155^aD ± 0.002
FFA (% oleic acid)
T1	0.50^dA ± 0.01	0.59^cA ± 0.01	0.71^bA ± 0.01	0.82^aA ± 0.01
T2	0.45^dB ± 0.006	0.51^cB ± 0.008	0.60^bB ± 0.008	0.71^aB ± 0.01
T3	0.44^dB ± 0.006	0.48^cCB ± 0.012	0.60^bB ± 0.012	0.70^aB ± 0.009
T4	0.41^dC ± 0.015	0.47^cC ± 0.018	0.53^bC ± 0.018	0.66^aC ± 0.019

Note: Superscripts bearing different small alphabets row wise differ significantly (P < 0.05); superscripts bearing different capital alphabets column wise differ significantly (P < 0.05).

T1, control; T2, 10% replacement of meat by jackfruit; T3, 20% replacement of meat by jackfruit; T4, 30% replacement of meat by jackfruit.

The mean values of 2-Thiobarbituric acid reactive substances (TBARS) value are given in Table 4. The observed TBARS value ranged between 0.129 ± 0.001 and 0.169 ± 0.001. Amongst all, lowest TBARS value was found in chevon patties having 30% immature jackfruit at 0 day of storage and highest in control on nineth day of storage. It might be due to the high fat content in control as compared to chevon patties containing 30% immature jackfruit. TBARS values increased significantly (P < 0.05) with increase in storage period. This observation was in agreement with the findings of Brewer et al. (1998), Witte et al. (1970). Increased TBARS value during storage might be due to oxidative rancidity as reported by Tan and Shelef (2002), Yadav and Sharma (2008).

Free fatty acid (FFA) content of chevon patties incorporated with selected levels of immature jackfruit during storage at refrigerated temperature (4°C ± 1°C) is presented in Table 4. There was a significant (P < 0.05) gradual increase in the FFA in both control and immature jackfruit-treated chevon patties. The mean value of FFA ranged between 0.41 ± 0.015 and 0.82 ± 0.01. The minimum FFA value was found in the chevon patties having 30% immature jackfruit at 0 day of storage and maximum in control at nineth day of storage.

The significant (P < 0.05) increase in FFA content with the increase in storage period was due to the enzymatic or microbial lipolysis of fat. Modi et al. (2007) reported that freshly prepared dehydrated chicken kebab mix had FFA value of 0.99% which increased significantly (P < 0.05) to 1.74% during 6 months of storage. Similar increase in FFA content during storage has also been reported by Nayak and Tanwar (2004), Nagamallika et al. (2006) in chicken patties, Das et al. (2008) in goat meat patties and Kumar et al. (2011) in chicken nuggets. In general, FFA content alone did not act as criteria for acceptability of products but it is a good quality indicator for oxidative changes in the meat products during storage.

3.5. Microbial profile

Mean ± SE values of total plate count (TPC) and yeast and mould in goat meat patties stored at refrigeration temperature for different storage periods are presented in Table 5.

Table 5. Change in microbiological quality of chevon patties prepared using jackfruit during storage at 4°C ± 2°C (mean ± SEM).

Sample	0 day	3 days	6 days	9 days
Total plate count (log cfu/g)
T1	2.78^cA ± 0.07	3.85^bA ± 0.04	4.85^aA ± 0.04	5.02^aA ± 0.10
T2	2.63^dBA ± 0.08	3.68^cBA ± 0.08	4.69^bA ± 0.08	5.01^aA ± 0.09
T3	2.43^dCB ± 0.10	3.56^cCB ± 0.07	3.91^bB ± 0.03	4.81^aBA ± 0.04
T4	2.28^dC ± 0.11	3.35^cC ± 0.09	3.73^bB ± 0.07	4.65^aB ± 0.07
Yeast and mould (cfu/g)
T1	0^d ± 0	0.90^cA ± 0.03	1.21^bA ± 0.02	1.42^A ± 0.03
T2	0^d ± 0	0.85^cA ± 0.04	1.14^bB ± 0.02	1.24^B ± 0.02
T3	0^A ± 0	0.86^bA ± 0.03	1.09^aCB ± 0.03	1.18^aB ± 0.05
T4	0^d ± 0	0.85^A ± 0.04	1.04^bC ± 0.02	1.15^aB ± 0.04

Note: Superscripts bearing different small alphabets row wise differ significantly (P < 0.05); superscripts bearing different capital alphabets column wise differ significantly (P < 0.05).

T1, control; T2, 10% replacement of meat by jackfruit; T3, 20% replacement of meat by jackfruit; T4, 30% replacement of meat by jackfruit.

3.5.1. Total plate count (TPC)

The mean values of TPC ranged from 2.28 ± 0.11 to 5.02 ± 0.10 in chevon patties during storage period at refrigeration temperature. The microbial growth was slightly higher in the control as compared to immature jackfruit-treated patties which might be due to some antimicrobial properties of the jackfruit. Baliga et al. (2011) reported that presence of different compounds like the flavonoids, sterols and prenylflavones are responsible for antimicrobial properties. However, the TPC value increased significantly (P < 0.05) among all groups during entire storage study.

This increase in TPC of chevon patties with increase in storage periods might be due to multiplication of micro-organisms during storage (Bawa et al. 1988). Parallel results have been reported for chicken patties by Mahapatra et al. (1984), Kondaiah et al. (1988); Padda (1989) for goat meat products. In the present study, higher TPC values in the control were observed on nineth day refrigeration temperature (log 5.02 ± 0.10 cfu/g). According to Bureau of Indian Standards (1992), aerobic plate count should not be beyond log 4/g in ready-to-eat sausage products. However, the level of TVCs to the extent of log 5.0/g was considered as the maximum limit for acceptability of the product (Bauermann 1979) and log 7.0/g was considered as indicative of starting of spoilage (Panda 1971).

3.5.2. Yeast and mould

The mean values of yeast and mould ranged from 0.0 ± 0.0 to 1.42 ± 0.03. The yeast and mould growth was slightly higher in the control as compared to immature jackfruit-treated patties which might be due to some antifungal properties (flavonoids, sterols and prenylflavones) of the jackfruit. Baliga et al. (2011) also reported antifungal properties of flavonoids, sterols and prenylflavones. However, the yeast and mould counts increased significantly (P < 0.05) with advancement of refrigerated ageing. The results are also supported by the findings of Sutherland et al. (1975) on vacuum-packed beef and with Babji et al. (2000) on vacuum-packed minced goat meat.

3.5.3. Sensory evaluation

Mean ± SE values of appearance and colour, odour, juiciness, texture, tenderness, flavour and overall acceptability of goat meat patties stored at refrigeration temperature for different periods are shown in Table 6.

Table 6. Sensory scores of chevon patties prepared using jackfruit during storage at 4°C ± 2°C (mean ± SEM).

		Level of jackfruit in goat meat patties
Parameter	Treatment	0 day	3 days	6 days	9 days
Appearance and colour	T1	6.22^aC ± 0.13	5.94^baC ± 0.10	5.72^cbC ± 0.11	5.44^cC ± 0.12
	T2	6.72^aB ± 0.16	6.44^baB ± 0.12	6.17^bB ± 0.12	5.78^cB ± 0.10
	T3	7.28^aA ± 0.14	6.89^bA ± 014	6.61^cbA ± 0.12	6.28^cA ± 0.11
	T4	7.00^aBA ± 0.20	6.56^bBA ± 0.12	6.22^A ± 0.10	6.22^bA ± 0.10
Odour	T1	6.39^aB ± 0.11	6.11^baB ± 0.11	5.83^cbB ± 0.12	5.67^cC ± 0.11
	T2	6.89^aA ± 0.14	6.67^baA ± 0.11	6.33^cbA ± 0.11	6.00^cCB ± 0.14
	T3	7.22^aA ± 0.15	6.83^baA ± 0.15	6.61^cbA ± 0.12	6.27^cA ± 0.14
	T4	7.00^aA ± 0.20	6.67^bA ± 0.14	6.39^bA ± 0.11	6.25^bBA ± 0.11
Juiciness	T1	6.44^aB ± 0.12	6.05^bC ± 0.13	5.78^cbC ± 0.10	5.56^cB ± 0.12
	T2	6.78^aB ± 0.13	6.50^aB ± 0.12	6.17^bB ± 0.12	5.83^cB ± 0.09
	T3	7.33^aA ± 0.11	6.94^bA ± 0.10	6.67^cbA ± 0.14	6.39^cA ± 0.11
	T4	6.61^B ± 0.18	6.44^B ± 0.12	6.28^B ± 0.11	6.20^A ± 0.10
Texture	T1	6.44^aB ± 0.12	6.11^baC ± 0.14	5.83^cbC ± 0.12	5.61^cB ± 0.12
	T2	6.72^aB ± 0.14	6.50^baB ± 0.12	6.22^cbBA ± 0.13	5.89^cBA ± 0.11
	T3	7.28^aA ± 0.14	6.94^aA ± 0.13	6.56^bA ± 0.12	6.22^bA ± 0.15
	T4	6.67^B ± 0.16	6.39^CB ± 0.12	6.17^CB ± 0.15	6.1.0A ± 0.14
Tenderness	T1	6.28^aC ± 0.14	6.11^baB ± 0.14	5.89^cbC ± 0.11	5.56^cB ± 0.12
	T2	6.67^aBA ± 0.11	6.44^baBA ± 0.12	6.22^cbBA ± 0.13	5.89^cBA ± 0.14
	T3	7.00^aA ± 0.11	6.67^baA ± 0.11	6.44^cbA ± 0.12	6.11^cA ± 0.14
	T4	6.50^aCB ± 0.12	6.33^baBA ± 0.11	6.00^bB ± 0.14	5.80^bA ± 0.14
Flavour	T1	6.17^aC ± 0.15	5.83^baC ± 0.12	5.61^cbC ± 0.12	5.44^cB ± 0.12
	T2	6.56^aCB ± 0.15	6.33^baB ± 0.14	6.11^cbB ± 0.14	5.78^cB ± 0.13
	T3	7.11^aA ± 017	6.78^baA ± 0.13	6.56^cbA ± 0.12	6.28^cA ± 0.14
	T4	6.83^aBA ± 0.19	6.61^baBA ± 0.12	6.28^bBA ± 0.14	6.10^bA ± 0.14
Overall acceptability	T1	6.11^aC ± 0.14	5.61^bC ± 0.12	5.44^cbC ± 0.12	5.22^cC ± 0.10
	T2	6.33^aCB ± 0.14	6.11^baB ± 0.16	5.89^cbB ± 0.11	5.61^cB ± 0.12
	T3	7.06^aA ± 0.17	6.67^bA ± 0.11	6.44^cbD ± 0.12	6.11^cA ± 0.13
	T4	6.56^aB ± 0.15	6.33^baBA ± 0.11	6.00^bB ± 0.16	5.74^bA ± 0.14

Note: Superscripts bearing different small alphabets row wise differ significantly (P < 0.05); superscripts bearing different capital alphabets column wise differ significantly (P < 0.05).

T1, control; T2, 10% replacement of meat by jackfruit; T3, 20% replacement of meat by jackfruit; T4, 30% replacement of meat by jackfruit.

There was significant (P < 0.05) decrease in appearance and colour scores of chevon patties on 3, 6 and 9 days at refrigeration temperature. Reddy and Rao (1997) reported that the colour of duck patties decreased significantly with the advancement of storage interval. Biswas (2002) noted that the gradual decline in colour scores of ground pork patties stored at refrigeration storage might be due to pigment and lipid oxidation resulting in non-enzymatic browning between lipid oxidation and amino acid. There was significant (P < 0.05) decrease in odour, juiciness, texture, tenderness, flavour and overall acceptability score of goat meat patties on 3, 6 and 9 days at refrigeration temperature. Eyas (2001) indicated that the diminished juiciness might be due to the loss of moisture from the products during storage as low-density polyethylene packages were permeable to moisture. The gradual decrease in textural scores might be due to release of moisture (Wu et al. 2000) and depletion of fat during storage (Biswas 2002). Jay (1996) reported that it might be due to the breakdown of muscle fibre protein by bacterial action resulting in decreased water binding capacity. The lower flavour score might be related to increased malonaldehyde formation due to oxidation of fat, which has detrimental effect on flavour and firmness of product (Miller et al. 1980). Deterioration of flavour during storage might be due to microbial growth, formation of FFA and oxidative rancidity (Suresh et al. 2003). Biswas (2002) stated that the decrease in overall acceptability scores of pork patties might be due to decrease in value of other sensory attributes. The results were in congruent with Reddy and Rao (1997) who reported that duck patties could be acceptable up to 6 days under refrigeration storage. Pangas et al. (1998) found that overall acceptability of fried chicken gizzard stored under refrigeration was significantly low as compared to fresh samples. The results of this study were in agreement with Nath (1992) in chicken patties.

4. Conclusions

The present investigation showed that use of jackfruit for development of patties may be the good alternative in the series of values added products. It might be nutritionally rich meat product with good sensory attributes and good physico-chemical characteristics. The incorporation of the jackfruit in the chevon patties also help in maintain in the proper shape and size than control. These products can also be stored for about 9 days in very good conditions under refrigeration.