Effect of Carrageenan and Oat Flour on Quality Characteristics of Meat Kofta

Abstract

Meat kofta, a typical Indian meat product, was prepared by incorporation of 8% oat flour and 0.5, 1.0, or 1.5% carrageenan in formulation with an objective of developing a low-fat and high fiber meat product. The uncooked, cooked and deep fat fried kofta were analyzed for proximate composition and pH. The addition of oat flour and carrageenan moisture retention, cooking yield, diameter, juiciness, water holding capacity (WHC) texture profile analysis (TPA), color traits, and sensorily acceptance were assessed in cooked and fried kofta. Inclusion of oat flour and carrageenan in the formulation resulted in significant (P < 0.05) higher moisture retention and the yield on cooking and frying. There was a significant increase (P < 0.05) in diameter in cooked kofta, whereas, a decrease in diameter was noticed for fried kofta as compared to control sample decreased (P < 0.05) in fried kofta compared to control (without carrageenan and oat flour). The cooked kofta had a better juiciness than control (P < 0.05); however, inclusion of carrageenan and oat flour in the formulation lowered juiciness in fried kofta (P < 0.05). Uncooked and cooked meat kofta had higher (P < 0.05) WHC than control. Hardness of cooked and fried kofta decreased (P < 0.05) and adhesiveness increased (P < 0.05) with the increase of carrageenan levels in the formulation. Low fat high fiber meat kofta can be prepared by using 8.0% oat flour and 0.5% carrageenan without much detrimental effect on its physicochemical and sensory attributes.

Keywords:

• Carrageenan
• Oat flour
• Meatballs
• Kofta
• Comminuted meat
• Binders
• Low fat meat products
• High fiber

INTRODUCTION

Meatballs are a popular traditional preparation from Indian cuisine and are often referred to as meat Kofta. Meat Kofta is prepared by using meat. The minced meat is mixed with Bengal gram (Cicer ariatinum) flour or refined wheat flour and hydrogenated fat (10–20%) to obtain an emulsion. Spices and condiments are added to the meat emulsion in specific proportions for an appetizing flavor and made into round shaped kofta manually. To prepare meat kofta curry these balls either directly cooked along with curry or it is deep fat fried and then cooked in curry. Similar product known as ‘Kung-wan’ is a popular meat product in Taiwan as well as in other Chinese communities.[1] Although “Kung-wan” is a popular food, it is becoming a health concern for consumers because of its high content of animal fat.[1] Raw meatball (Cig Kofte) is commonly consumed as appetizer in Turkey.[2]

Increased health consciousness among consumbers about the risks involved with consumption of fat rich has resulted in an increased demand for healthy foods have high fiber and low fat. High fiber-low fat meat products are one such products that are in demand. Apparent relationship between dietary fat and development of cardiovascular disease, hypertension and obesity has prompted consumers to be aware of and concerned about, the amount of fat in their diet.[3]

Major limitation of low fat processed meat product is the decline in palatability with fat reduction.[4,5,6] Research on replacement of fat to improve the quality of ground meat products has been reported. There is evidence that reducing the fat level from approximately 20% to between 5% to 10% in beef burgers, result in reduction of tenderness, juiciness, flavour intensity, and overall product palatability.[7] The utilization of cereal and fruit fibers in the development of low fat dry fermented sausages showed adverse effect on sensory properties of the product.[8] Fat levels showed a significant effect on sensory properties of Turkish meatballs.[9] To overcome these problems starches, hydrocolloids,[10,11,12] soya protein concentrates, and/or isolates and dietary fibers[1,13,14] and vegetable gums15,16] were used as an ingredient in the meat product formulations.

Various authors reported that incorporation of carrageenan in the development of low fat ground beef patties,[17] in sausages,[18,19,20] and in restructured pork nuggets,[21] improved the product quality. It has been found that carrageenan does not improve cook yield in low fat beef sausages[22] or frankfurters.[23] Other researchers have advocated that, when oat fiber was added to low fat bologna, cook losses i.e. weight losses during cooking increased.[24] In this investigation, an attempt has been made to study the effect of oat flour (a source of fiber), in combination with different levels of carrageenan (a fat replacer), on the quality characteristics of the low fat and high fiber meat kofta.

MATERIAL AND METHODS

Materials

Manually deboned sheep meat (whole carcass obtained from a sheep of 3.5 to 4 years age weighing ∼25 Kg; slaughtered by Halal method at the municipal slaughter house of Mysore city) procured from local market was brought to the laboratory and washed with clean water. For each replicate, 4 kg deboned meat chunks were used for the preparation of kofta. All subcutaneous fat, intermuscular fat, external fascia and all adhering connective tissues were removed from the muscles and the meat was cut in to chunks of 25–50 mm size. The deboned lean meat chunks were ground through a 4.5 mm plate using meat mincer (Model LM 10K, Koneteollisuus Oy, Finland). The refined wheat flour, oat flour, hydrogenated fat, spice mix (garam masala; a mixture of spices containing clove, cinnamon, cardamom, black pepper, mace, nutmeg, and soon as it is called locally), cumin powder, turmeric powder, red chilly powder and common salt as mentioned in formulation (Table 1) were procured locally. The ginger and garlic powders were prepared in laboratory by drying the cleaned, peeled, washed and grated whole ginger and peeled garlic bulb in hot air cross flow drier at 80–90°C [C. M. Equipments & Instruments (India) Pvt. Ltd, Bangalore, India]. Although the temperature of drying (used in the present study) results in some loss of flavor and sensory properties, sufficient flavor and sensory qualities required for the product are retained in the dried material. The dried ginger and garlic were ground into fine powder using a domestic grinder (Sumeet Research & Holdings Ltd., Chennai, India). The resultant ginger and garlic powder was sieved through #60 mesh and packed in dry amber colored glass bottles and stored at room temperature until further use.

Table 1 Formulation to prepare 1 Kg of uncooked meat dough for the preparation of mutton kofta.

Ingredients	Quantities (%)Control	Quantities (%)Experimental
Deboned meat	78.00	78.00
Wheat flour	9.00	8.5/8.0/7.5
Hydrogenated fat	8.00	-
Oat flour	-	8.0
Carrageenan	-	0.5/1.0/1.5
Garam masala	0.22	0.22
Ginger powder	0.32	0.33
Garlic powder	0.33	0.33
Cumin powder	0.44	0.44
Turmeric powder	0.22	0.22
Red chilly powder	1.36	1.36
Common salt	2.10	2.10

Chemicals

The carrageenan (from Irish moss) was procured from Hi-Media Laboratories Pvt. Ltd. Mumbai. All other chemicals used for evaluating the quality of the product was of Analar /GR grade.

Formulation and Processing

The ground meat as obtained above was divided into four batches. The control sample did not contain any additioves, other three experimental batches were prepared by incorporation of carrageenan and wheat flour. The level of wheat flour or wheat flour in combination with carrageen was maintained at 9.0% (w/w) in both control and experimental samples (i.e., wheat flour at 9%; or 8.5% wheat flour +0.5% carrageenan; or 8% wheat flour+1% carrageenan; or 7.5% wheat flour + 1.5% carrageenan). All the three experimental batches had oat flour at least 8% level replacing the 8% fat from the control. The total level of ingredients were remained constant (Table 1). The control sample had wheat flour (9.0%) along with 8.0% fat and spices. The formulation and preparation of control and experimental meat kofta were selected by carrying out a few preliminary trials. In preliminary trials, it was found that more than 8% oat flour adversely affecting the sensory quality of the product. The binder mix was obtained by mixing wheat flour (for control), oat flour, and carrageenan in a Hobert mixer (Model N-50, Hobart Paddle Mixer, OH USA) for 3–4 min, whereas, the spices mix was made by mixing garlic powder, ginger powder, cumin powder, turmeric powder, red chilly powder, salt and spice mix for 2–3 min in a mixer. The binder mix and spices mix was blended together further 3–4 min to obtain the meat kofta mix. The mixing of ingredients in steps was carried out for a uniform distribution of all ingredients in minced meat. The minced meat was further mixed with kofta mix in a mixer for 4–5 min to obtain meat kofta dough. Meat kofta dough was shaped in round balls manually to get raw meat kofta (20 g each).

Chemical Composition

Proximate composition was analyzed according to method as described by the AOAC.[25] The fat content in the product was determined by extraction in 2:1 chloroform: methanol solvent. Carbohydrate was calculated by difference. pH of product was measured by immersing in glass-calomel electrode directly in sample and using pH meter (Cyberscan 1000, Singapur). All determinations of each batch were performed in triplicate.

Cooking Parameters

One batch (10 pieces) of meat kofta were cooked in boiling water (700 ml) for 20 min where as another batch were deep fat fried at the temperature of 145 ± 5°C for 4 minutes by constantly stirring in refined sunflower oil (400 ml). Care has been taken to ensure that the kofta samples were fully immersed in water or in oil during cooking or frying. The heat processed kofta samples were cooled to room temperature (27 ± 2°C). The physico-chemical characteristics of processed koftas were studied and the results were compared with control sample. The fried kofta was further used for the preparation of kofta curry for sensory evaluation. The percent yield of the cooked or fried product was determined by weighing the shaped meat kofta before and after cooking in boiling water or frying in oil, respectively, by using the following equation.

(1)

The percent increase or decrease in size was determined by measuring the diameter of meat kofta ball before and after cooking in boiling water or frying in oil, by using the following equation.

(2)

(3)

Determination of moisture retention, juiciness and water holding capacity (WHC) are important for evaluating the quality of processed meat products. Moisture retention relates to the total water retained by the product after processing; whereas, juiciness is the estimation of the release of juice, from the meat, on mastication. Further, WHC is a physical method for determing the quantity of water bound to the meat constituents. The following equations were used for the calculating the moisture retention,[9] juiciness,26] and WHC.[27]

(4)

(5)

(6)

where t is Total fluid loss during heating and centrifuging; T is Difference between A and B (i.e., B – A); B is Weight of sample before heating; A is weight of sample after heating and centrifuging; and M is total water content in the sample

Instrumental Texture Profile Analysis (TPA)

The textural profile (hardness, cohesiveness, chewiness, springiness and adhesiveness) analysis of uncooked, cooked and fried product was determined by using Lloyds Texturometer (LR5K, UK). The instrument was programmed for a 100 kg load cell and cross head speed of 100 mm/ minute, probe diameter 35 mm. The round ball shaped kofta was trimmed from sides to get a square cube and then it was cut with the help of a mould size 40 mm × 12 mm (diameter × thickness) to obtain uniform size samples. The values were recorded based on the software, Nexigen version 6.0 (Lloyd Instruments Ltd, Hampshire, England) available with the instrument. The mean value of five readings for each texture profile analysis is reported.

Color Traits

Color characteristics of uncooked, cooked and fried product in terms of L (Lightness), a (redness) and b (yellowness) were determined using Hunter color measuring system (Labscan XE, Virginia,USA) at 2° view angle. The system was calibrated using white tile as standard and the L, a, and b values for the standard were 90.71, −1.11, and 0.63 respectively. The mean value of five readings of each color traits of samples is reported.

Sensory Evaluation

Preparation of product for sensory evaluation

The cooked and fried meat kofta were used separately for the preparation of traditional meat kofta curry (Fig. 1). The traditional curry was prepared and raw meat kofta was cooked in afore said curry. The cooking of kofta continued till a cooked meaty aroma was felt when the internal temperature of kofta, measured by a digital recorder thermometer (Aptec, Chennai, India) by inserting a probe in the product, reached 83 ± 3°C. For the preparation of meat kofta curry from fried kofta, the fried kofta was added in the meat curry and cooked, till a roasted meaty aroma was felt when the internal temperature of the kofta was to 83 ± 3°C.

Figure 1 Flow diagram for the preparation of traditional meat kofta curry.

Sensory Analysis

The kofta was removed from the curry and were subjected to sensory evaluation for appearance (shape retention), color, flavour, texture, juiciness, and overall acceptability. The sensory evaluation was carried out by 10 in-house trained panelists using 9 – point Hedonic scale.[28] The panel included 5 male and 5 female panelists aged 38–45 years. Samples for evaluation were served separately in a well lit room on white enamel plates. The mean score for each attribute is reported. The kofta were served to panelists at 55 ± 5°C for evaluation.

Statistical Analysis

Level of carrageenan in different experimental batches only was considered as an independent variable to compare the effect of its different levels. All the experiments were carried out in four batches (n = 4). The means of all the parameters were examined for significance by analysis of variance (ANOVA) and mean separation, in case of significant effect, was accomplished by Duncan's Multiple Range Test using software STATISTICA by keeping the level of significance at 95%.[29]

RESULTS AND DISCUSSION

Chemical Composition

Proximate composition and pH values of uncooked, cooked and deep fat fried meat kofta are given in Table 2. Moisture content in carrageenan containing kofta, cooked and fried was higher (P < 0.05), compared to corresponding control samples. An increase in moisture contents in cooked beef burgers formulated with wheat fibers was observed by Mansour and Khalil[30] and Trius et al.[16] This could be because of the ability of carrageenan particles to retain more water than control as explained by Egbert et al.,[31] No difference (P > 0.05), in protein and ash were found among the three levels of carrageenan and with control in cooked and uncooked kofta. This occurrence has also been noted previously by Bloukas and Paneras[32] in low fat frankfurter containing rice bran in formulation. Different levels of carrageenan and oat flour in the formulation also did not affect (P > 0.05) in the fat and carbohydrates content of uncooked, cooked and fried kofta. However, compared to control, fat contents decreased (P < 0.05) and carbohydrates were increased (P < 0.05) in product. Compositional changes in the product could be attributable to the change in total product mass during cooking as observed by Mittal and Barbut.[19] No changes (P > 0.05) were observed in ash contents and pH of all the samples. The cooked and fried kofta had a water activity of 0.97 and 0.94, respectively (results not shown in Table 2).

Table 2 Effects of incorporation of different levels of carrageenan and 8.0% oat flour on chemical composition (on dry weight basis) and pH of mutton kofta.

Parameters	Control	Carrageenan, %
		0.5	1.0	1.5
Uncooked mutton Kofta
Moisture, %	63.2 ± 2.4^a	64.4 ± 1.9^b	64.3 ± 1.5^b	64.4 ± 1.4^b
Fat, %	29.9 ± 3.3^a	14.6 ± 2.4^b	13.9 ± 2.1^b	14.4 ± 1.8^b
Protein %	49.3 ± 2.3^a	49.5 ± 3.7^a	50.6 ± 2.4^a	49.7 ± 2.1^a
Ash, %	4.5 ± 0.5^a	4.8 ± 0.4^a	4.9 ± 0.4^a	4.9 ± 0.5^a
Carbohydrate,*%	16.2 ± 1.8^a	31.0 6.1^b	30.5 ± 4.1^b	31.0 ± 3.6^b
pH	5.85 ± 0.06^a	5.70 ± 0.11^a	5.75 ± 0.11^a	5.74 ± 0.07^a
Cooked mutton Kofta
Moisture, %	65.9 ± 1.2^a	68.8 1.5^b	70.2 ± 1.4^bc	71.1 ± 1.0^c
Fat, %	28.5 ± 2.8^a	14.0 ± 1.6^b	13.5 ± 0.8^b	14.7 ± 1.9^b
Protein, %	50.4 ± 3.0^a	48.7 ± 3.4^a	51.0 ± 4.3^a	53.5 ± 3.0^a
Ash, %	3.5 ± 0.1^a	4.0 ± 0.4^a	4.1 ± 0.3^a	4.4 ± 0.6^a
Carbohydrate,*%	13.8 ± 3.9^a	33.3 ± 3.7^b	31.3 ± 4.1^bc	27.4 ± 1.7^c
pH	6.10 ± 0.28^a	5.90 ± 0.31^a	5.94 ± 0.28^a	5.98 ± 0.29^a
Deep fat fried mutton Kofta
Moisture,%	54.3 ± 1.8^a	59.8 ± 3.4^b	60.2 ± 3.5^b	60.9 ± 4.2^b
Fat, %	33.7 ± 1.1^a	19.8 ± 1.6^b	20.7 ± 1.3^b	20.6 ± 1.1^b
Protein, %	43.7 ± 1.7^a	50.1 ± 1.9^b	49.3 ± 3.0^b	49.9 ± 2.1^b
Ash, %	2.7 ± 0.2^a	3.2 ± 0.4^a	3.3 ± 0.6^a	3.6 ± 0.5^a
Carbohydrate,*%	19.8 ± 1.3^a	26.9 ± 2.7^b	26.5 ± 4.0^b	26.1 ± 3.8^b
pH	5.87 ± 0.29^a	5.79 ± 0.20^a	5.86 ± 0.16^a	5.74 ± 0.18^a
*by difference;
All the values indicate mean ± SD, (n = 4).
Means in a row with a different superscript letter differ (P < 0.05).

Cooking Parameters

Yield and moisture retention were higher (P < 0.05) in cooked or fried kofta containing carrageenan and oat flour compared to corresponding control samples (Table 3). An increase in cooking or frying yield (P < 0.05) and increase in moisture retention in fried kofta was also observed as the levels of carrageenan were increased. Data revealed an optimum-cooking yield in either case (cooked or fried) obtained when 0.5% carrageenan was incorporated in the formulation. The moisture retention was optimum (P < 0.05) at 1.0% carrageenan level in fried kofta. The improvement in cooking yield and in moisture retention at the aforesaid levels of carrageenan could be due to the optimum moisture binding in the matrix by the added oat flours and carrageenan under studied (cooked or fried) processing conditions, whereas, the lower yield in control samples might be attributed to the excessive fat separation and water release during cooking or frying. Similar observations were made in frankfurter sausages[16,27,33] and in Turkish meatballs.[9] The percentage of moisture and also moisture retention increased in low-fat patties because of water binding ability of carrageenan.[34] Anon[35] reported that the oat flour can absorb large quantity of water (water absorption 586%) without increasing product viscosity. Claus and Hunt[24] observed an increase in cooking loss in low fat bologna containing oat fiber.

Table 3 Effects of incorporation of different levels of carrageenan and 8.0% oat flour on cooking characteristics of mutton kofta

Cooking Characteristics	Control	Carrageenan, %
		0.5	1.0	1.5
Cooked sheep meat kofta
Cooking yield, %	92.7 ± 3.4^a	107.2 ± 1.7^b	108.2 ± 2.0^bc	111.7 ± 2.0^c
Moisture retention, %	64.2 ± 3.9^a	74.9 ± 2.4^b	76.1 ± 2.0^b	77.6 ± 1.9^b
Increase (+) or Decrease (−) in diameter, %	(−) 3.9 ± 0.6	(+) 3.4 ± 0.8^a	(+) 3.8 ± 0.7^a	(+) 4.2 ± 0.2^a
Deep fat fried mutton kofta
Cooking (frying) yield, %	71.0 ± 1.7^a	79.5 ± 4.5^b	83.3 ± 4.1^bc	85.7 ± 4.4^c
Moisture retention, %	41.1 ± 2.6^a	42.4 ± 2.7^a	49.1 ± 3.1^bc	49.2 ± 2.5^c
Decrease in diameter, %	4.3 ± 0.2^a	3.5 ± 0.3^b	2.2 ± 0.3^c	2.3 ± 0.3^c
All the values indicate mean ± SD, (n = 4).
Means in a row with a different superscript letter differ (P < 0.05).

Control kofta showed a reduction of 3.9 ± 0.6% in diameter whereas, carrageenan and oat flour containing kofta showed an increase in diameter by cooking (Table 3). It is worthy to mention that kofta containing carrageenan and oat flour had increased (P < 0.05) in size on cooking, whereas, it was decreased (P < 0.05) in fried kofta compared to control. Different levels of carrageenan had no effect (P > 0.05) on size of kofta on cooking but it was decreased (P < 0.05) in fried kofta as the carrageenan levels increased form 0.5 to 1.0 %. This increase and decrease in diameter could be because of difference in moisture retention behavior, as moisture retention in carrageenan-cooked kofta was much higher (74.9 ± 2.4 to 77.6 ± 1.9%) than fried kofta (42.4 ± 2.7 to 49.2 ± 2.5%) (Table 3). Also, this could be due to the binding and stabilizing property of carrageenan, which held the meat particles together and resisted changes in the shape of the product and because of ability of carrageenan to form complex with water and protein.[31] Carageenan and oat flour, may have greater ability of holding water at cooking temperature (95 ± 3°C) than the frying temperature (140 ± 5°C). At higher temperature the denaturation of protein is more resulting into more release of water and thus greater decrease in WHC and greater shrinkage of product.[36] The present findings are in agreement with those obtained by Mansour and Khalil[30] who observed that the reduction in diameter of low fat beef burgers was significantly improved by the addition of wheat fibers.

Texture Profile Analysis (TPA)

Hardness of the cooked and fried kofta decreased (P < 0.05) and adhesiveness of cooked kofta were increased (P < 0.05) with the increase of the carageenan level (Fig. 2). A decrease (P < 0.05) in chewiness in fried kofta was observed, whereas, it showed insignificant adhesiveness. It was also observed that the hardness, chewiness and springiness were less (P < 0.05) and adhesiveness was more (P < 0.05) in uncooked kofta compared to control. Further, high temperature of frying might be one of the factors for the very low adhesiveness values observed in fried kofta, as it affects the binding properties of the ingredients used. However, low adhesiveness did not affect the product quality negatively (Table 3). The variation in texture of low fat and high fiber kofta could be attributed to substitution of fat with water (more water retention on cooking), which could impart a soft mushy texture to the product.[10,37] There seemed to be appropriate binding and gelling attributes imparted to the product when carrageenan was added along with oat flour in the formulation. Carrageenan has been reported to improve cohesiveness of pork sausages because of its gelling and binding nature[34] and texture quality of ground beef.[31] Differences (P < 0.05) were found in textural quality of chicken sausage with different fat levels.[38] Low shear force was observed by Mansoor and Khalil[30] in beef burger formulated with wheat fiber and by Suman and Sharma[39] in low fat buffalo meat patties.

Figure 2 Effect of incorporation of different levels of carrageenan and (8.0%) oat flour on texture profile of the uncooked, cooked, and fried meat kofta. Treatment with different superscript differ (P < 0.05).

WHC and Juiciness

The addition of carrageenan and oat flour had effects (P < 0.05) on WHC and juiciness of cooked and fried kofta (Fig. 3). Uncooked carrageenan-containing kofta had more (P < 0.05) WHC and were more juicy and cooked kofta were also juicier compared to control. No difference (P > 0.05) in WHC was found among the levels of carrageenan in uncooked product, whereas, it had effected (P < 0.05) in cooked kofta. The present findings are agreeing with earlier findings.[19,33] There was no fluid loss during heating and centrifuging of fried kofta, as shown by the measurement of WHC indicating a high WHC (∼100%) of fried kofta.²⁷ Juiciness of uncooked and cooked kofta was increased (P < 0.05) by incorporation of carrageenan and oat flour in formulation, than control. This could be due to higher moisture retention in cooked kofta (Table 3). However, juiciness in fried kofta reduced by 19.5, 13.2, and 8.8%, compared to control (25.2 ± 1.7%), in 0.5, 1.0, and 1.5% carrageenan containing samples respectively (P < 0.05) although the moisture retention was better. This may be attributed to over all loss of available moisture in case of fried kofta at high temperatures of frying. Gujral, et al.,[40] who had reported an increase in juiciness in low fat patties from goat meat. An inverse relationship between the fat level and juiciness values were also reported by Hughes et al.[27] and Pietrasik and Duda.[33]

Figure 3 Effect of incorporation of different levels of carrageenan and (8.0%) oat flour on WHC and juiciness of the uncooked, cooked, and fried meat kofta. Treatment with different superscript differ (P < 0.05).

Color Traits

The color attributes of cooked meat products arise mainly from the pigmentation of meat with which they are made and the additives which were used in the formulation. Carrageenan and oat flour had marginal (P > 0.05) effect on Hunter color L (lightness), a (redness), and b (yellowness) values for all uncooked, cooked or fried kofta (Fig. 4). The addition oat flour and 1.0% carrageenan resulted in a lighter product (highest L) color (P > 0.05) in cooked and fried kofta (Fig. 4), whereas, the control cooked samples resulted in a darker colored (lowest L) (P > 0.05) product. There were no difference in a and b values (P > 0.05) among the different levels of carrageenan used in formulation. Similar observations were made in cooked frankfurter[27] and in uncooked and cooked beef burgers formulated with wheat fibers.[30] There was no apparent relationship between color and fat content; the observed differences might be attributed to the normal biological variability of the meat used.[39]

Figure 4 Effect of incorporation of different levels of carrageenan and (8.0%) oat flour on color characteristics of the uncooked, cooked, and fried meat kofta. Treatment with different superscript differ (P < 0.05).

Sensory Evaluation

Scores of all sensory attributes for carrageenan and oat flour kofta were higher (P < 0.05) compared to control (Table 4). Rating by the panel also showed that carrageenan levels did not affect (P > 0.05) the sensory quality of the fried product. Appearance scores of the cooked and fried carrageenan containing kofta were higher (P < 0.05) compared to control. The levels of carrageenan used also affected appearance score (P < 0.05) in cooked kofta, whereas, it did not (P > 0.05) in fried kofta. This was mainly because of more shrinkage or irregular shape in control samples observed than carrageenan containing kofta. The irregular shape could be due to more release of water and denaturation of protein. In carrageenan containing kofta, the moisture retention was more (Table 3) and hence shape was better retained. Meatballs formulated with 4% corn flour had lower (P > 0.05) scores for appearance regardless of the fat level.[9]

Table 4 Effects of incorporation of different levels of carrageenan and 8.0% oat flour on sensory properties of mutton kofta.

Sensory quality attributes	Control	Carrageenan, %
		0.5	1.0	1.5
Cooked mutton kofta
Appearance (shape retention)	5.2 ± 0.2^a	7.7 ± 0.3^b	8.1 ± 0.2^bc	8.4 ± 0.3^c
Colour	6.8 ± 0.2^a	7.0 ± 0.2^a	7.0 ± 0.4^a	7.2 ± 0.7^a
Flavour	6.9 ± 0.1^a	7.5 ± 0.4^b	7.6 ± 0.2^b	7.5 ± 0.4^b
Texture	6.3 ± 0.4^a	7.7 ± 0.1^b	8.1 ± 0.1^c	8.2 ± 0.3^c
Juiciness	5.8 ± 0.2^a	7.6 ± 0.2^b	8.1 ± 0.3^c	8.2 ± 0.3^c
Overall acceptability	6.1 ± 0.1^a	7.5 ± 0.2^b	8.0 ± 0.1^c	8.1 ± 0.2^c
Deep fat fried mutton kofta
Appearance (shape retention)	5.4 ± 0.6^a	7.7 ± 0.3^b	8.1 ± 0.5^b	8.1 ± 0.1^b
Colour	6.4 ± 0.9^a	7.2 ± 0.5^a	6.8 ± 0.3^a	6.8 ± 0.4^a
Flavour	7.1 ± 0.3^a	7.2 ± 0.2^a	7.2 ± 0.2^a	7.1 ± 0.4^a
Texture	5.3 ± 0.1^a	7.7 ± 0.4^b	7.8 ± 0.4^b	7.9 ± 0.5^b
Juiciness	6.1 ± 0.3^a	7.9 ± 0.4^b	7.8 ± 0.5^b	8.1 ± 0.2^b
Overall acceptability	6.1 ± 0.2^a	7.7 ± 0.1^b	7.8 ± 0.0^b	7.9 ± 0.2^b
All the values indicate mean ± SD, (n = 4).
Means in a row with a different superscript letter differ (P < 0.05).

The panelists did not show any difference (P > 0.05) in color scores of cooked and fried kofta than to control. The addition of oat flour in combination with carrageenan did not (P > 0.05) alter flavour in fried kofta but improved the flavour of the cooked kofta. Higher flavour scores (P > 0.05) of the cooked kofta are probably due to higher moisture retention and higher rate of release of flavour compounds. The difference in flavour due to cooking is probably a direct function of temperature and degree of moisture in the meat.[41] However, carrageenan or oat fiber had no effect on the flavour characteristics of frankfurters.[27]

Cooked and fried kofta formulated with carrageenan and oat flour had better (P < 0.05) texture and juiciness than control (Table 4), despite lower fat content in carrageenan product. Since fat makes an important contribution to the texture of meat products, it was anticipated that fried meat kofta containing carrageenan and oat flour, being lower fat, would decrease texture and overall acceptability scores compared to control with higher fat contents. But, it was not found so in present investigation. The present findings are agreeing with findings of Marquez et al.,[42] who reported that reduced fat frankfurter had improved texture. The improvement in texture scores could be due to fat mimicking property of carrageenan.[43,19] However, Ahemd et al.,10] and Serdaroglu and Sapanci-Ozsumer[5] reported that low fat communicated meat products tend to be tougher than higher fat products. The overall acceptability scores were also higher (P < 0.05) in cooked or fried kofta containing carrageenan and compared to control.

CONCLUSIONS

Oat flour and carrageenan at 8 and 0.5%, respectively, were found to be desirable for preparation of low fat high fiber meat kofta that had optimum product quality. The addition of oat flour and carrageenan resulted in significant reduction of fat absorption during deep fat frying. The cooking yield was dependent more on the preparation methods and the ingredients used for product formulation. Cooking yield and moisture retention increased with increasing levels of carrageenan. However, hardness of the cooked and fried kofta decreased with the increase in carageenan level. Juiciness as a function of carrageen level increased in case of cooked kofta whereas it reduced in case of fried kofta as compared to control. Sensory evaluation of product indicated a better acceptability of experimental kofta as compared to control.