Abstract
The present study was conducted to determine the effect of three different levels of sorbic acid (0.1 %, 0.2 % and 0.3 %) on the shelf life and storage quality of Kaladhi. Kaladhi was prepared from pasteurized buffalo milk standardized to 6 % fat and 9 % SNF with coagulation at 40 °C using 5 % lactic acid as a coagulant. Kaladhi prepared without sorbic acid served as control and was compared with the products treated with different levels of sorbic acid for a storage period of 35 days at ambient temperature. The results showed a significant (P < 0.05) effect of sorbic acid on most of the physicochemical parameters i.e. titratable acidity, free fatty acid content (% oleic acid) and thiobarbituric acid value which showed a decreasing trend with increasing concentration of sorbic acid. However, a non-significant (P > 0.05) effect of sorbic acid was observed on pH and proximate parameters of the product. Kaladhi treated with 0.3 % sorbic acid retained most desirable physicochemical and sensory properties throughout the storage period hence, was considered the best.
Keywords: Kaladhi, Sorbic acid, Ambient storage, Quality attributes
Introduction
Traditional dairy products are an integral part of Indian heritage and possess great social, religious, cultural, medicinal and economic importance. In addition to preservation of milk solids for longer time at room temperature, manufacture of traditional dairy products add value to milk and also provide tremendous employment opportunity (Pal and Raju 2007). Traditional dairy products not only have established market in India but also great export potential because of strong presence of Indian diaspora in many parts of the world (Rao and Raju 2003).
Scenario of cheese production in India is quite bright because of the facts that cheese has all the beneficial attributes of an ideal dairy product. Furthermore, emergence of new global economic reforms has unfastened the door to the Indian dairy industry to penetrate the international cheese market (Kanawjia 2007). Technologies have been appropriately standardized for manufacture of various types of cheeses and have evolved to such an extent that most cheese is produced by employing modern technology. Hence, if traditional Indian cheese varieties like Kaladhi are proposed to be marketed on commercial scales, it becomes imperative that suitable technologies be developed for their production, packaging and preservation (Bukhari et al. 2012).
Kaladhi is a hard and dry cheese variety of Jammu and Kashmir which is prepared by directly acidifying the milk with organic acids without the use of rennet and starter. It is prepared by acidifying milk with some easily available organic acids as coagulating agents and working out coagulum into a pat. Small balls made out of the pat are later given a circular shape of varying diameters. The product is prepared either from cow’s or buffalo’s or sheep’s milk or a mixture thereof. Besides being a salubrious food, it is believed to possess antidiarrhoeal, anticold and antitussive properties (Pal et al. 2003; Bukhari et al. 2011, 2012). Buttermilk cheeses in Europe, Tibet cheese in Tibet, Chugga or Churpi in Nepal and native paneer are some of the documented products with similarities in characteristics and utilization (Pal et al. 2003; Bukhari et al. 2011, 2012). The typical acidic flavor and preparation procedure differentiate Kaladhi from similar coagulated milk products. It is mostly prepared as a cottage enterprise with hardly any control over the quality with main problem being its limited shelf life because of spoilage by various microorganisms especially by molds attributed to its low pH. Mold growth not only affects the appearance but also results in the production of off-flavors and off-odors besides causing toxicity in the product. Thus, there is an ample scope for extending the shelf life of the product.
Sorbic acid (2, 4 hexadienoic acid) is a well established natural organic compound used as a food preservative. It acts up to the pH of 6.5 and reduces the various lipolytic changes. Its activity gets enhanced with decreasing pH of the product. Singh et al. (1989) reported a shelf life of 36 days in paneer stored at room temperature using sorbic acid at 0.15 %. Thus, in lieu of all these facts and lack of scientific reports on the same, an attempt was made to study the effect of different levels of sorbic acid (0.1 %, 0.2 % and 0.3 %) on the shelf life and storage quality of Kaladhi.
Materials and methods
Kaladhi was stored at ambient temperature in the bamboo baskets covered with muslin cloth for 35 days without any packaging. Traditionally the product is also stored in the baskets. The samples were drawn at regular intervals on 0th (after addition of sorbic acid), 14th, 28th and 35th day and evaluated for the various parameters.
Source of milk
Fresh buffalo milk procured from the local market of Jammu was used in all the experiments after suitable standardization as per the Pearson Square Method. Buffalo milk was standardized to 6 % fat level with 9 % SNF to develop the Kaladhi with most desirable quality characteristics (Ahmad et al. 2010). Standardized milk was pasteurized and each batch of Kaladhi was prepared from 10 kg of milk.
Preparation of Kaladhi
Fresh buffalo milk standardized to 6 % fat and 9 % SNF was coagulated at 40 °C to obtain the Kaladhi with most desirable quality characteristics (Ahmad et al. 2010; Bukhari et al. 2012). Traditionally the milk is also coagulated at the same temperature to obtain product with desirable quality.
Standardized buffalo milk was heated to 40 °C and coagulated at this temperature using 5 % lactic acid as a coagulant till the attainment of a uniform curd. The curd was immediately drained through muslin cloth without pressing. The curd was then opened, molded into pieces of convenient size and placed in petri plates of uniform size used as moulds. The curd was then taken out of the moulds and allowed to dry at room temperature in bamboo baskets. Regular turning of the product after 5 h interval was ensured for at least 3 days until sufficient moisture was lost through evaporation. The product was allowed to dry in a clean and moisture free environment abstaining from direct sun drying. Kaladhi was dipped in sorbic acid solutions after drying i.e. on 3rd day for 30 s. Kaladhi which was not dipped in the sorbic acid solution served as control. The wet yield was taken immediately after production and the dry yield on 3rd day after drying.
Acid coagulant
5 % lactic acid was used as a coagulant in the present study to develop this dairy product with most desirable quality characteristics (Bukhari et al. 2012).
Analytical procedures
pH
The pH of Kaladhi was determined as per the method of O’Keeffe et al. (1976) by using a digital pH meter (Systronics Digital pH Meter 802, Serial No. 603).
Proximate composition
The moisture, protein, fat and ash content of Kaladhi were determined by standard methods using hot air oven (Yorco sales Pvt. Ltd. India, Model-YS1-431, S. No. 02B2843), Kjeldhal assembly, Soxhlet extraction apparatus, and Muffle furnace respectively (AOAC 1995).
Thio barbituric acid (TBA) value
Thiobarbituric acid value of Kaladhi was determined using the method of Witte et al. (1970).
Free fatty acids
The method suggested by Koniecko (1979) was followed to measure the free fatty acids in Kaladhi samples.
Titratable acidity
The method as described by AOAC (1995) for cheese was followed to determine the titratable acidity in Kaladhi.
Sensory evaluation
The sensory evaluation of the product was carried for attributes, namely appearance, flavour, juiciness, sourness, texture and the overall acceptability of fresh and stored samples by a panel of seven experienced members composed of scientists and research scholars of the Division based on a 8-point descriptive scale, wherein 8 denoted “extremely desirable” and 1 denoted “extremely undesirable” (Seman et al. 1987). Coded samples for sensory evaluation were prepared by shallow frying of Kaladhi in oil and served warm to panelists.
Statistical analysis
Each experiment was replicated thrice in duplicate. Means and standard errors were calculated for different parameters. Factorial design of experiment was followed. Analysis of variance (Two-way ANOVA for storage studies and One-way ANOVA for sensory studies) was performed using statistical software package (SPSS-16). The data obtained were subjected to Duncan’s multiple range tests for comparing the means to find the effects between treatments and storage periods for various parameters in different experiments at 5 % level of significance. There were seven sensory judges for each treatments x replication combination.
Results and discussion
Physicochemical parameters
The Mean ± SE values of various physicochemical parameters of Kaladhi at different storage periods are presented in Table 1.
Table 1.
Effect of ambient storage (21–25 °C) on physicochemical characteristics of Kaladhi treated with different concentrations of sorbic acid (Mean ± SE)*
| Treatments | Storage period (days) | |||
|---|---|---|---|---|
| 0 | 14 | 28 | 35 | |
| pH | ||||
| Control | 4.2 ± 0.03A | 4.1 ± 0.03B | 4.0 ± 0.04B | 4.0 ± 0.03B |
| 0.1 % sorbic acid | 4.2 ± 0.03A | 4.0 ± 0.03B | 4.0 ± 0.02B | 4.0 ± 0.02B |
| 0.2 % sorbic acid | 4.2 ± 0.02A | 4.1 ± 0.02B | 4.0 ± 0.02B | 4.0 ± 0.02B |
| 0.3 % sorbic acid | 4.2 ± 0.02A | 4.1 ± 0.03AB | 4.1 ± 0.03B | 4.1 ± 0.03B |
| Titratable acidity (% Lactic acid) | ||||
| Control | 0.490 ± 0.0023A | 0.529 ± 0.0030aB | 0.550 ± 0.0031aC | 0.566 ± 0.0036aD |
| 0.1 % sorbic acid | 0.490 ± 0.0017A | 0.525 ± 0.0030abB | 0.545 ± 0.0024 abC | 0.551 ± 0.0082abC |
| 0.2 % sorbic acid | 0.489 ± 0.0021A | 0.523 ± 0.0026abB | 0.541 ± 0.0026bC | 0.555 ± 0.0021abD |
| 0.3 % sorbic acid | 0.489 ± 0.0020A | 0.520 ± 0.0020bB | 0.537 ± 0.0023bC | 0.548 ± 0.0021bD |
| Free fatty acids (% Oleic acid) | ||||
| Control | 0.0573 ± 0.0003A | 0.0623 ± 0.0004aB | 0.0667 ± 0.009aC | 0.0701 ± 0.009aD |
| 0.1 % sorbic acid | 0.0573 ± 0.0002A | 0.0615 ± 0.0003abB | 0.0637 ± 0.004bC | 0.0676 ± 0.004bD |
| 0.2 % sorbic acid | 0.0573 ± 0.0002A | 0.0608 ± 0.0004bB | 0.0624 ± 0.05bcC | 0.0654 ± 0.004cD |
| 0.3 % sorbic acid | 0.0573 ± 0.0003A | 0.0596 ± 0.0004cB | 0.0612 ± 0.003cC | 0.0627 ± 0.005dD |
| TBA (mg mal./ Kg) | ||||
| Control | 0.276 ± 0.0038A | 0.375 ± 0.0031aB | 0.792 ± 0.0032aC | 1.217 ± 0.0033aD |
| 0.1 % sorbic acid | 0.276 ± 0.0032A | 0.363 ± 0.0030bB | 0.730 ± 0.0038bC | 1.191 ± 0.0029bD |
| 0.2 % sorbic acid | 0.276 ± 0.0031A | 0.337 ± 0.0034cB | 0.708 ± 0.0045cC | 1.172 ± 0.0044cD |
| 0.3 % sorbic acid | 0.276 ± 0.0030A | 0.318 ± 0.0031dB | 0.682 ± 0.0035dC | 1.146 ± 0.0043dD |
*Mean ± SE with different superscripts in a column wise (small alphabet) and row wise (Capital alphabet) differ significantly (P < 0.05)
n = 6 for each treatment
pH
The mean pH values of Kaladhi for control samples as well as for all sorbic acid treated samples on 0th day of storage were significantly (p < 0.05) higher than the mean values of Kaladhi on all other days of storage. The mean values of pH on 14th, 28th and 35th day were comparable to each other for all the treatments as well as control. The highest values were observed on 0th day of storage for all the samples. The values showed a decreasing effect of storage on the pH of the Kaladhi. Bukhari et al. (2012) also reported a declining trend in the pH of the Kaladhi stored at ambient temperature. Pal and Garg (1989), Kumar and Bector (1991) and Pal et al. (1993) reported similar findings in paneer. Alalade and Adeneye (2007) also reported a decreasing effect of storage on pH values of Wara Cheese under frozen storage.
Perusal of the data indicates that the pH values did not fall within the range of reported values for similar coagulated milk products like paneer probably because the acid used for coagulation in the present study furnished a higher hydrogen-ion concentration in the final product. Further, the amount of acid used for coagulation of milk for Kaladhi preparation is more than that used in paneer preparation because of lower temperature of coagulation (40 °C).
Titratable acidity
The mean values of titratable acidity of Kaladhi increased significantly (p < 0.05) in all the treatments as well as in control samples throughout the period of storage. However, the mean values of 0.1 % sorbic acid treated Kaladhi on 28th and 35th day were comparable (p > 0.05) to each other. On 0th day, the mean values of titratable acidity were comparable to all treated and control samples. The mean values of control samples were significantly (p < 0.05) higher than 0.3 % sorbic acid treated Kaladhi samples from the 14th day onwards. However, the values of both 0.1 % and 0.2 % sorbic acid treated samples were comparable (p > 0.05) with control and 0.3 % sorbic acid treated samples. In treated samples, the rate of increase was slower when compared with control. Bukhari et al. (2012) also reported an increasing trend in the titratable acidity of Kaladhi stored at ambient temperature. Pal and Garg (1989), Kumar and Bector (1991) and Pal et al. (1993) also observed similar findings in paneer.
The mean values of titratable acidity of Kaladhi indicate that the rate of increase in sorbic acid treated samples was lower in comparison to control samples because sorbic acid is an antimicrobial agent and it retards the growth of spoilage causing organisms. Similar findings were observed by Pal and Garg (1989), Shukla and Vaid (2004) and Sanyal et al. (2006) in paneer, oil based paneer pickle and reduced fat paneer respectively.
Free fatty acids (% Oleic acid)
The mean free fatty acid values of Kaladhi increased significantly (p < 0.05) in all the treatments as well as in control samples throughout the period of storage. The mean free fatty acid values of control samples were significantly (p < 0.05) higher than all treated samples from 14th day onwards. However, the values of control on 14th day were comparable to the free fatty acid values of 0.1 % sorbic acid treated samples. Among the treatments, the free fatty acids values showed a significantly (p < 0.05) decreasing trend on all days of storage with increasing level of sorbic acid. On 35th day, the values for free fatty acids differed significantly (p < 0.05) among all the samples, being highest for control and lowest for 0.3 % sorbic acid treated sample.
The free fatty acids values of control samples increased more rapidly. Bukhari et al. (2012) also reported similar increase in the free fatty acid values of Kaladhi stored at ambient temperature. The rate of increase of free fatty acid values was lower in case of sorbic acid treated samples in comparison to control. The probable reason may be that sorbic acid is an antimicrobial agent and it retards the growth of spoilage causing organisms. Similar types of findings were observed by Pal and Garg (1989), Shukla and Vaid (2004) and Sanyal et al. (2006) in paneer, oil based paneer pickle and reduced fat paneer respectively.
Thiobarbituric acid value (mg malonaldehyde/ Kg)
The mean thiobarbituric acid values of Kaladhi showed significantly (p < 0.05) increasing trend throughout the period of storage in all the treated samples as well as in control. The mean thiobarbituric acid values of the control Kaladhi showed significantly (p < 0.05) higher values than treated samples from the 14th day of storage onwards whereas on 0th day, the values were comparable. Among the treated samples the values showed a significantly decreasing trend with increasing level of sorbic acid on all days of storage except on 0th day when the values were comparable to each other. In treated samples, the rate of increase was slower when compared with control. The rate of increase was lowest for 0.3 % sorbic acid treated sample (value increased from 0.276 to 1.146) as the rate of increase was indirectly related to the level of sorbic acid. The probable reason may be that sorbic acid being an antimicrobial agent retards the growth of spoilage causing organisms and thus reduces the lipolytic changes. Bukhari et al. (2012) also reported similar increase in the thiobarbituric acid values of Kaladhi stored at ambient temperature. Similar types of findings were observed by Pal and Garg (1989), Kumar and Bector (1991), Pal et al. (1993), Shukla and Vaid (2004) and Sanyal et al. (2006) in paneer.
All these findings observed during storage could be supported by the fact that the product was exposed to spoilage causing microorganisms since it was stored at temperatures most suitable for the growth of such invasive microorganisms. Therefore, all the changes during storage reported in the present study were probably due to the growth of spoilage causing organisms. Similar findings were reported by a number of other workers as well (Bukhari et al. 2012; Pal and Garg 1989; Kumar and Bector 1991 and Pal et al. 1993).
Proximate composition
The Mean ± SE values for proximate composition of Kaladhi are presented in Table 2.
Table 2.
Effect of ambient storage (21–25 °C) on proximate composition of Kaladhi treated with different concentrations of sorbic acid (Mean ± SE)*
| Treatments | Storage period (days) | |||
|---|---|---|---|---|
| 0 | 14 | 28 | 35 | |
| Moisture (%) | ||||
| Control | 31.2 ± 0.22A | 29.8 ± 0.23B | 28.8 ± 0.19aC | 28.4 ± 0.23C |
| 0.1 % sorbic acid | 31.5 ± 0.16A | 30.1 ± 0.18B | 29.2 ± 0.16abC | 28.9 ± 0.16C |
| 0.2 % sorbic acid | 31.3 ± 0.24A | 30.2 ± 0.16B | 29.3 ± 0.15abC | 29.1 ± 0.23C |
| 0.3 % sorbic acid | 31.0 ± 0.36A | 30.2 ± 0.18B | 29.4 ± 0.17bC | 29.1 ± 0.17C |
| Fat (%) | ||||
| Control | 37.4 ± 0.20A | 36.9 ± 0.19B | 36.4 ± 0.15aC | 35.8 ± 0.14aD |
| 0.1 % sorbic acid | 37.5 ± 0.20A | 37.1 ± 0.19AB | 36.7 ± 0.18abBC | 36.2 ± 0.19abC |
| 0.2 % sorbic acid | 37.5 ± 0.18A | 37.1 ± 0.14AB | 36.8 ± 0.15abBC | 36.5 ± 0.16bcC |
| 0.3 % sorbic acid | 37.5 ± 0.19A | 37.3 ± 0.16AB | 36.9 ± 0.17bBC | 36.7 ± 0.18cC |
| Protein (%) | ||||
| Control | 25.1 ± 0.18A | 24.8 ± 0.22AB | 24.4 ± 0.22B | 24.2 ± 0.21aB |
| 0.1 % sorbic acid | 25.2 ± 0.16A | 24.9 ± 0.17AB | 24.5 ± 0.18B | 24.4 ± 0.18abB |
| 0.2 % sorbic acid | 25.2 ± 0.17A | 24.9 ± 0.17AB | 24.6 ± 0.15B | 24.5 ± 0.16abB |
| 0.3 % sorbic acid | 25.2 ± 0.14 | 25.1 ± 0.15 | 24.9 ± 0.16 | 24.8 ± 0.16b |
| Ash (%) | ||||
| Control | 2.38 ± 0.02A | 2.42 ± 0.0 2AB | 2.45 ± 0.02B | 2.46 ± 0.02B |
| 0.1 % sorbic acid | 2.37 ± 0.02A | 2.40 ± 0.02AB | 2.42 ± 0.02AB | 2.44 ± 0.02B |
| 0.2 % sorbic acid | 2.39 ± 0.01A | 2.41 ± 0.02AB | 2.45 ± 0.02AB | 2.47 ± 0.02B |
| 0.3 % sorbic acid | 2.39 ± 0.01A | 2.41 ± 0.02AB | 2.44 ± 0.02B | 2.46 ± 0.01B |
*Mean ± SE with different superscripts in a column wise (small alphabet) and row wise (Capital alphabet) differ significantly (P < 0.05)
n = 6 for each treatment
Moisture
The mean values of moisture percentage of Kaladhi decreased significantly (p < 0.05) throughout the period of storage for all the treated samples and control up to 28th day of storage. The mean values of moisture percentage of the treated samples and control were comparable to each other on all days of storage except on 28th day of storage when mean moisture value of control was significantly lower than 0.3 % sorbic acid treated sample. Among the treatments, there was a non-significant (p < 0.05) difference throughout the storage period. The decrease in moisture content over the storage period might be due to loss of some amount of moisture by evaporation as the product was exposed to open ambient environment. Similar trend was reported by Bukhari et al. (2012) who also reported a decreasing trend in the moisture content of the Kaladhi stored at ambient temperature. Rao et al. (1984), Arora and Gupta (1980), Shukla and Vaid (2004) and Sanyal et al. (2006) also reported similar findings in paneer.
The mean moisture values of Kaladhi, however, are much lower than those reported for paneer. Since paneer is kept in water in market practice whereas Kaladhi is regularly turned during storage to allow for maximum evaporative loss of moisture, it can be the most appropriate reason for such a variation.
Fat
The mean values of the fat percentage of Kaladhi of all treatment samples as well as control decreased significantly (p < 0.05) throughout the storage period. However, the difference remained non-significant (p < 0.05) between various treatments throughout the storage period. In general, the fat content of Kaladhi decreased with increasing storage period but the rate of decrease was slower in sorbic acid treated samples. This decrease in the total fat content of the product stored at ambient temperature might be a result of loss of fat/leaching out of fat from the product during storage which is in agreement with the results of Bukhari et al. (2012) who reported a similar loss of fat/leaching out of fat from the product and also observed a similar decrease in the fat content of Kaladhi during storage at ambient temperature. As the product is not stored under refrigerated conditions and is not packaged under traditional conditions, some of the fat and protein leach-out from the product during storage particularly during summer season. This decrease in the fat content can also be attributed to greater microbial load in the product which might have caused lipolysis to a greater extent. As sorbic acid reduced the microbial counts significantly (p < 0.05), the rate of decrease of fat was slower in sorbic acid treated samples. Rao et al. (1984), Arora and Gupta (1980), Shukla and Vaid (2004) and Sanyal et al. (2006) also reported a decrease in fat content of paneer during storage.
Fat content of Kaladhi ranged from 35.80 % to 37.50 % which appear to be higher than the values reported for paneer. A higher fat content of Kaladhi may be attributed to a much lower moisture content of the final product. The values, however, were in agreement with the values of Kaladhi prepared by Bukhari et al. (2011) by using citric acid as a coagulant.
Protein
The mean protein percentage values of Kaladhi for all the treated samples as well as control were comparable (p > 0.05) to each other on all days of storage except on 35th day when the control values were significantly lower than 0.3 % sorbic acid treated samples. In general, the protein values of Kaladhi showed a significantly (p < 0.05) decreasing trend throughout the storage period for all the treatment samples as well as control. This decrease in the protein content of the product stored at ambient temperature might be a result of loss of proteins/leaching out of proteins from the product during storage which is in agreement with the results of Bukhari et al. (2012) who reported a similar loss/leaching-out of proteins and fats from the Kaladhi during storage at ambient temperature and also observed a similar decrease in the protein content of the Kaladhi. The decrease in the protein content during storage can also be attributed to greater microbial load in the product which might have caused proteolysis to a greater extent. Rao et al. (1984), Arora and Gupta (1980), Shukla and Vaid (2004) and Sanyal et al. (2006) also observed a decrease in fat content of paneer during storage. Kilic et al. (2004) also reported a similar decrease in protein content of Turkish fresh goat cheese during storage.
The protein values of the Kaladhi were higher as compared to the values in paneer which may be attributed to a reasonably lower moisture content of Kaladhi as compared to paneer.
Ash
The mean ash percentage values of Kaladhi of control as well as treatment samples showed a significantly (p < 0.05) increasing trend throughout the period of storage. However, the ash content of control as well as treated samples were comparable (p > 0.05) to each other on all days of storage. The decrease in the moisture content of the Kaladhi over the storage period might be the reason for the increase in the ash content of the Kaladhi. Bukhari et al. (2012) also observed a similar increase in the ash content of the Kaladhi stored at ambient temperature. Similar trends were reported by Rao et al. (1984), Arora and Gupta (1980), Shukla and Vaid (2004) and Sanyal et al. (2006) in paneer during storage.
Sensory parameters
The Mean ± SE values for various sensory attributes of Kaladhi are presented in Table 3. The values for appearance and color ranged from 7.3 to 7.5 with highest score (7.5) for control samples and the lowest score (7.3) for the samples treated with 0.3 % sorbic acid. The appearance and color scores of control samples were significantly (p < 0.05) higher than 0.3 % sorbic acid treated samples and were comparable (p > 0.05) to the scores of 0.1 % sorbic acid and 0.2 % sorbic acid treated samples. All the three samples treated with sorbic acid were comparable (p > 0.05) to each other however, the scores showed a decreasing trend. In general, the addition of sorbic acid did not cause any deleterious effect on the appearance and color scores of Kaladhi. These findings were in agreement with Pal et al. (1993) and Sanyal et al. (2006) who also observed similar trends in case of paneer.
Table 3.
Effect of various concentrations of sorbic acid on the sensory attributes of Kaladhi (Mean ± SE)*
| Sorbic acid levels (%) | ||||
|---|---|---|---|---|
| Parameters | Control | 0.1 % | 0.2 % | 0.3 % |
| Appearance & colour | 7.5 ± 0.06a | 7.5 ± 0.08ab | 7.4 ± 0.06ab | 7.3 ± 0.07b |
| Flavor | 7.6 ± 0.07a | 7.5 ± 0.07ab | 7.4 ± 0.06ab | 7.3 ± 0.07b |
| Texture | 7.7 ± 0.04a | 7.6 ± 0.04b | 7.5 ± 0.03b | 7.6 ± 0.04b |
| Sourness | 7.4 ± 0.07 | 7.4 ± 0.07 | 7.3 ± 0.06 | 7.2 ± 0.06 |
| Overall acceptability | 7.7 ± 0.08 | 7.7 ± 0.07 | 7.6 ± 0.07 | 7.6 ± 0.08 |
*Mean ± SE with different superscripts in a row differs significantly (P < 0.05)
n = 21 for each treatment
The values for flavor ranged from 7.3 to 7.6 with highest score for the control samples and the lowest score for the samples treated with 0.3 % sorbic acid showing a decreasing trend. The scores for control samples were significantly (p < 0.05) higher than 0.3 % sorbic acid treated samples. However, the samples treated with sorbic acid were comparable (p > 0.05) to each other. The decreasing trend of the flavor scores may be attributed to the slight bitterness that sorbic acid added to the product and comparatively higher fat levels of the control samples. These findings were in agreement with Pal et al. (1993) and Sanyal et al. (2006) who also reported similar results in case of paneer.
The scores for texture ranged from 7.7 to 7.5 with highest scores for the control samples and the lowest scores for the samples treated with 0.2 % sorbic acid. The mean texture score of control samples was significantly (p < 0.05) higher than all samples treated with sorbic acid. However, the samples treated with sorbic acid were comparable (p > 0.05) to each other. The mean scores for sourness ranged from 7.2 to 7.4 with highest score observed for control samples followed in order by 0.1 % sorbic acid, 0.2 % sorbic acid and 0.3 % sorbic acid treated samples. The sourness scores of all the sorbic acid treated samples and control were comparable (p > 0.05) to each other. The antimicrobial nature of sorbic acid may be responsible for the decreasing sourness of the product with increasing levels of the sorbic acid. The values for overall acceptability ranged between 7.6 and 7.7. The values did not differ significantly (p > 0.05) and the scores were within acceptable limits for all treatments. In general, the addition of sorbic acid did not cause any deleterious effect on the sensory attributes of Kaladhi. These findings were in agreement with Pal et al. (1993) and Sanyal et al. (2006) who also observed similar trends in case of paneer.
Conclusion
Kaladhi prepared from pasteurized buffalo milk standardized to 6 % fat and 9 % SNF with coagulation at 40 °C using 5 % lactic acid as a coagulant and treated with various levels of sorbic acid had acceptable scores for various physicochemical properties and sensory scores. It may be concluded that sorbic acid effectively retards the various degradation changes in the Kaladhi. On the basis of different physicochemical and sensory parameters, sorbic acid at 0.3 % level proved to be optimum in the preparation of Kaladhi.
Contributor Information
S. R. Ahmad, Email: sh.rafeh@gmail.com
V. Pathak, Email: pathakvet@gmail.com
Z. F. Bhat, Email: zuhaibbhat@yahoo.co.in
S. A. A. Bukhari, Email: adivet@gmail.com
References
- Ahmad SR, Pathak V, Kumar A. Efficacy of Sorbic Acid as Preservative in Kaladhi on sensory and microbiological parameters. J Vet Pub Hlth. 2010;8(2):105–110. [Google Scholar]
- Alalade OA, Adeneye JA. The effect of short-term frozen storage on the chemical composition and coliform microflora of wara cheese ‘wara cheese under frozen storage’. Am J Food Technol. 2007;2(1):44–47. doi: 10.3923/ajft.2007.44.47. [DOI] [Google Scholar]
- AOAC . Official methods of analysis. 16. Washington DC: Association of Official Analytical Chemists; 1995. [Google Scholar]
- Arora VK, Gupta SK. Effect of low temperature storage on paneer. Indian J Dairy Sci. 1980;33(3):374–380. [Google Scholar]
- Bukhari SAA, Pathak V, Bhat ZF, Ahmed SR. Evaluation of efficacy of citric acid as coagulant in the preparation of Kaladhi-a hard and dry cheese. Beverage and Food World. 2011;38(8):61–64. [Google Scholar]
- Bukhari SAA, Pathak V, Bhat ZF, Ahmed SR (2012) Effect of ambient storage on the quality characteristics of Kaladhi-an acid coagulated milk product. Am J Food Technol. doi:10.3923/ajft.2012
- Kanawjia SK (2007) Cheeses from Buffalo milk. In: Souvenir, International Conference on “Traditional Dairy Products”, NDRI, Karnal (India), 14–17 Nov, p-80
- Kilic S, Uysal H, Kavas G, Akbulut N, Kesenkas H. Manufacture and some properties of Turkish Fresh Goat Cheese. Pak J Biol Sci. 2004;7(6):1037–1039. doi: 10.3923/pjbs.2004.1037.1039. [DOI] [Google Scholar]
- Koniecko ES. Handbook for meat Chemists. Wayne: Avery; 1979. [Google Scholar]
- Kumar P, Bector BS. Enhancement of shelf-life of paneer with food additives. Indian J Dairy Sci. 1991;44:577–584. [Google Scholar]
- O’keeffe RB, Fox PF, Daly C. Contribution of rennet and starter proteases to proteolysis in Cheddar cheese. J Dairy Res. 1976;43:97. doi: 10.1017/S0022029900015636. [DOI] [Google Scholar]
- Pal D, Garg FC. Utilization of sour buttermilk in the manufacture of paneer. Indian J Dairy Sci. 1989;42(3):589–594. [Google Scholar]
- Pal D, Raju PN (2007) Process modifications for the manufacture of Indian traditional dairy products from buffalo milk. In: Souvenir, International Conference on “Traditional Dairy Products”, NDRI, Karnal (India), 14–17 Nov, p-25
- Pal MA, Wani SA, Malik AH, Mir SD, Ishrat Maush Kraer-A hitherto undocumented traditional dairy product of Kashmir. Beverage and Food World. 2003;30(8):55–56. [Google Scholar]
- Pal MA, Yadav PL, Sanyal MK. Effect of paraffining on the physicochemical, microbiological and sensory characteristics of low fat paneer at low temperature storage. Indian J Dairy Sci. 1993;46:519–524. [Google Scholar]
- Rao KH, Raju PN. Prospects and challenges for Indian dairy industry to export dairy products. Indian J Dairy Biosci. 2003;14(2):72–78. [Google Scholar]
- Rao MN, Rao BVR, Rao TJ. Paneer from buffalo milk. Indian J Dairy Sci. 1984;37(1):50–53. [Google Scholar]
- Sanyal MK, Yadav PL, Gangopadhyay SK, Paul SC. Effect of coagulation temperature of buffalo milk added with sodium chloride on the quality of reduced fat paneer. Beverage and Food World. 2006;33(6):45–48. [Google Scholar]
- Seman DL, Moody WG, Fox JD, Gay N. Influence of hot and cold deboning on the palatability, textural and economic traits of restructured beef steaks. J Food Sci. 1987;52:879–882. doi: 10.1111/j.1365-2621.1987.tb14232.x. [DOI] [Google Scholar]
- Shukla FC, Vaid J. Studies on the storage stability of oil-based paneer pickle. Int J Dairy Technol. 2004;57(1):15–18. doi: 10.1111/j.1471-0307.2004.00116.x. [DOI] [Google Scholar]
- Singh L, Mohan MS, Puttalingamma V, Sankaran R. Preservation of paneer by sorbic acid. J Food Sci Technol. 1989;26(3):129–131. [Google Scholar]
- Witte VC, Krause GF, Bailey ME. A new extraction method for determining 2-thiobarbituric acid value of pork and beef during storage. J Food Sci. 1970;35:582–585. doi: 10.1111/j.1365-2621.1970.tb04815.x. [DOI] [Google Scholar]