East African Journal of Sciences (2019) Volume 13 (2) 185-194 ______________________________________________________________ Licensed under a Creative Commons *Corresponding Author. E-mail: mitikuguya@yahoo.com Attribution-NonCommercial 4.0 International License. ©Haramaya University, 2019 ISSN 1993-8195 (Online), ISSN 1992-0407(Print) Chemical Composition, Mineral Profile and Sensory Properties of Traditional Cheese Varieties in selected areas of Eastern Gojjam, Ethiopia Mitiku Eshetu1* and Aleme Asresie2 1School of Animal and Range Sciences, Haramaya University, P.O. Box 138, Dire Dawa, Ethiopia 2Department of Animal Production and Technology, Adigrat University, Adigrat, Ethiopia Abstract: This study was conducted to evaluate the chemical composition, mineral profile and sensory properties of Metata, Ayib and Hazo traditional cheese varieties in selected areas of Eastern Gojjam. The chemical composition and mineral content of the cheese varieties were analyzed following standard procedures. Sensory analysis was also conducted by consumer panelists to assess taste, aroma, color, texture and overall acceptability of these traditional cheese varieties. Metata cheese samples had significantly (P<0.05) lower moisture content and higher titratable acidity than Ayib and Hazo cheese samples. The protein, ash, fat contents of Metata cheese samples were significantly (P<0.05) higher than Ayib and Hazo cheese samples. Moreover, phosphorus, calcium, magnesium, sodium and potassium contents of Metata cheese samples were significantly (P<0.05) higher than that of Ayib and Hazo cheese samples. Metata cheese samples had also the highest consumer acceptability scores compared to Ayib and Hazo cheese samples. In general, the results of this work showed that Metata cheese has higher nutritional value and overall sensory acceptability. This could be due to the fermentation of the product for several months and use of different types of spices. Keywords: Chemical composition; Consumer acceptability; Mineral profile 1. Introduction The major fermented milk products in Ethiopia produced by smallholder farmers using traditional methods include Ergo (fermented sour milk), Ititu (fermented milk curd), Kibe (traditional butter), Neter Kibe (clarified butter), Ayib (cottage cheese), Arerra (defatted sour milk), Aguat (whey) (Gonfa et al., 2001) and metata (fermented cottage cheese variety) (Eyassu, 2013). Traditional cottage cheese (Ayib) is made from defatted sour milk obtained from churning of sour whole milk and then by heating the product on a slow flame until distinct curd forms. The shelf life of Ayib is limited to few days and therefore, it is either consumed at home or marketed as quickly as possible (Assefa et al., 2008). There are also some more traditional dairy products known in the mixed and pastoral production systems of the country. Metata, Hazo and Zureshekefign are the traditional fermented cottage cheese varieties produced in Northwestern highlands of Ethiopia (Eyassu, 2013; and Geremew et al., 2015). Awabal, Gozamin, Machakel and Dejen districts of East Gojjam Zone are important milk producing areas in Amhara National Regional State of northwestern highlands of Ethiopia. In these areas milk is produced from cows under traditional conditions and processed into different traditional cheese varieties such as Ayib, Metata, Hazo and Zureshekefign. These dairy products differ from the traditional cottage cheese. Metata cottage fermented cheese production involves the use of various spices, spontaneous fermentation for about 25 days coupled with continuous removal of whey. These products are more shelf stable compared to the most common Ayib (which can be kept only for a few days) and properly made Metata Ayib could be kept for more than 10 years if tightly sealed and stored in a cool place. Metata valued by the community for its medicinal and cultural values (Tegegne et al., 2013). These products could be of significant nutritional importance for the community with substantial contribution to the country’s economic development. However, there is no adequate information available on their chemical composition, mineral profile as well as sensory properties. Nevertheless, it is essential to understand such properties of these traditional dairy products in order to improve manufacturing procedures, standardize the processing parameters, and to provide basic information necessary to improve the quality of these dairy for households use and commercial purpose. The aim of this study was therefore, to evaluate the chemical composition, mineral profile and sensory properties of Metata, Ayib and Hazo traditional cheese varieties along the cheese value chain in selected areas of Eastern Gojjam, northwestern highlands of Ethiopia. 2. Materials and Methods 2.1. Description of the Study Areas East Gojjam is one of the Zones in the Amhara National Regional State of Ethiopia. It borders the Oromia National Regional State in the south, West Gojjam Zone in the west, South Gondar in the north, and South Wollo in the east. The bend of the Abay Mitiku and Aleme East African Journal of Sciences Volume 13 (2) 185-194 186 River defines the Zone's northern, eastern and southern boundaries. The Zone has seventeen districts of which four districts namely, Gozamin, Awabal, Dejen and Machakel districts were purposively selected based on dairy potential, history of dairy development interventions and number of crossbred dairy cattle. 2.2. Cheese Sampling Procedures and Layout A total of 216 samples (of ≈ 300g each) of the three traditional cheese varieties namely Metata, Ayib and Hazo were collected from dairy producers (120), dairy products retail shops and kiosks (60), and dairy cooperatives (36) from the four selected districts (Table 1; Figure 1). The samples were placed in sterile bottles (300 g) aseptically and stored in an icebox having ice packs, and delivered to the Ethiopian Food, Medicines and Health Care Administration and Control Authority (EFMHACA) and Bless Agrifood Laboratory Services for analysis. Total number of samples collected for each cheese variety was 72 (Table 1). Each sample was analyzed in duplicate for chemical composition, mineral profile and consumer acceptability tests. Fig 1. Ayib (A), Metata cheese variety (B) and Hazo cheese variety (C) Table 1. Cheese sampling procedures and layout Districts Sampling sources and cheese varieties Producers Cooperatives Dairy PRSK Metata Ayib Hazo Metata Ayib Hazo Metata Ayib Hazo Total Awabal 10 10 10 3 3 3 5 5 5 54 Gozamin 10 10 10 3 3 3 5 5 5 54 Machakel 10 10 10 3 3 3 5 5 5 54 Dejen 10 10 10 3 3 3 5 5 5 54 Total 40 40 40 12 12 12 20 20 20 216 Note: Dairy PRSK=Dairy product retail shops and kiosks. 2.3. Determination of Chemical Composition 2.3.1. Fat Content The Soxhlet fat extraction method was used to determine the fat content of traditional cheese (Metata, Ayib and Hazo) varieties as described by AOAC (1995) method 933.05. Three grams for each of the traditional cheese varieties was fed into a Soxhlet apparatus fitted with a 1-L round-bottom flask and condenser. The extraction was carried out for 8 hours using n-hexane (boiling point of 68-70°C). The solvent was removed by heating at 70°C in a hot dry oven (PN9410.GL. Britain). The recovered oil was then weighed and expressed as fat percentage. Where: Wa = thimble weight; Wb = sample weight before extraction; and Wc = sample weight after extraction 2.3.2. Moisture Content The moisture content of the traditional cheese (Metata, Ayib and Hazo) varieties was determined by drying three grams cheese samples in a forced draft oven (EDSC, 99H207: England) at 102±2°C for 3 hours. The moisture content of these traditional cheese samples was calculated according to Bradley et al. (1993). 2.3.3. Ash Content The ash content of cheese samples was determined according to the method described in AOAC (1995) method No. 935.42 by igniting the pre-dried cheese samples (≈ 2.0 g) that were used for moisture determination in a Muffle Furnace (Lindberg/Blue M Mitiku and Aleme Properties of traditional cheese varieties in Eastern Gojjam 187 Crucible furnace, top loading 100-1200 Serious, Fisher Scientific) at 550℃. Then, it was placed in desiccators while cooling and reweighed. The initial and final weights of the cheese samples were taken. The obtained ash weight was divided by original sample weight and expressed in percent. The ash content was calculated according to the following formula. 2.3.4. Protein Content The total nitrogen content of the traditional cheese- varieties (1 g) was determined by the Kjeldahl method as described by the International Dairy Federation (IDF, 1993). The crude protein content of these traditional cheese samples was determined by multiplying the nitrogen content by the factor 6.38. Where: % N= Percentage nitrogen by weight, Vs = Volume of HCl used for titration of sample Vb = Volume of HCl used for titration of the blank %CP = Percentage of crude protein %CP= %N *F; F = 6.38 was used as conversion factor 2.3.5. pH Determination The pH of the traditional cheese varieties was measured using a digital pH meter (Crison, Barcelona, Spain). 2.3.6. Titratable Acidity The titratable acidity of the traditional cheese varieties was determined by measuring 10 g of finely grounded traditional cheese samples and adding water (40℃) to a volume of 105 mL. After vigorous shaking, the mixture was filtered and an aliquot of the filtrate (25 mL) was titrated with 0.1 N sodium hydroxide solution using phenolphthalein as indicator. The titratable acidity was expressed as % lactic acid and calculated according to the procedure of AOAC (1995) method 920.124. 2.4. Determination of Mineral Profile The mineral profile (phosphorus, calcium, magnesium, sodium and potassium) of the traditional cheese varieties were determined according to the procedure of AOAC (1995) method 999.10 using Atomic Absorption Spectrophotometer (Model Phillip Pu9100x) with a hollow cathode lamp and a fuel rich flame (air-acetylene). Ten gram of each cheese sample were incinerated to a white ash at 550℃ in a muffle furnace for 4 hours, cooled and the ash was washed into 250 ml beaker with 30 ml of concentrated trioxonitrate acid evaporated to dryness on steam bath, the residue was further heated for 30 minutes, there after the sample was dissolved in 40 ml of hydrochloric acid (HCl) at a ratio of 1:1 and digested for about 2 hours on a hot plate magnetic stirrer. 1 ml of dilute hydrochloric acid was further added to the sample and boiled for about 1 hour, filtered with whatman number four filter paper, washed with HCl and the volume made up to 100 ml with distilled water. Samples were aspirated and the mean signal responses were recorded at each of the element respective wavelength. 2.5. Sensory Analysis Sensory evaluation of the traditional cheese (Metata, Ayib and Hazo) varieties was conducted by consumer panelists according to the method described by Resurrecin (1998). A total of fifty-eight adult consumers took part in the sensory analysis and they were requested to evaluate the sensory attributes of the cheese samples and fill the prepared questionnaire. Consumer panelists were selected based on the following criteria: age between 18-40 years old and they have to be “consumers” of fermented milk products. Metata, Ayib and Hazo traditional cheese samples (20 g) were placed in three-digit coded white plastic plates and served in a bright well-ventilated room. Bottled water was provided to the panelists to rinse their mouth after each taste. The taste, color, aroma, texture, appearance and overall acceptability of Metata, Ayib and Hazo traditional cheese samples were evaluated using a 5- point Hedonic scale (5 = like very much, 4 = like moderately, 3 = neither like nor dislike, 2 = dislike moderately and 1 = dislike very much). These traditional cheese samples were presented in a random fashion. The sensory evaluation was conducted at the Ethiopian Food, Medicines and Health Care Administration and Control Authority (EFMHACA). 2.6. Data Analysis Data related to chemical composition, mineral profile and sensory properties of the traditional cheese varieties (Metata, Ayib and Hazo) were analyzed using the General Linear Model procedure of the SAS (Version 9.1, 2008). Means were separated by Duncan Multiple Range Test. Significant differences were declared at 5% significance level. The model used; Yijk = µ + αi + єijk Where: Yijk = chemical composition, mineral profile and sensory properties of cheese varieties µ = overall mean; αi = cheese varieties; and єijk = random error. Mitiku and Aleme East African Journal of Sciences Volume 13 (2) 185-194 188 3. Results and Discussion 3.1. Chemical Composition of Traditional Cheese Varieties The moisture content of Metata cheese samples was significantly (P<0.05) lower than that of Ayib and Hazo cheese varieties regardless of their sources (Table 2). The lower moisture content of Metata cheese as compared to Ayib and Hazo cheese varieties might be due to continuous loss of water from the curd as a result of lactic acid development which causes curd contraction and syneresis during the production process and ripening period (Terzic-Vidojevic et al., 2007). The moisture content of Metata cheese observed in the current study is in agreement the finding of Eyassu (2013) who reported 42.3% moisture content for metata cheese variety, and with the moisture content of Halloumi cheese made from goat milk, cow milk and their mixture which was found to be 41.33% (Elgaml et al., 2017). Table 2. The chemical composition of the traditional cheese varieties (Mean ± SE) (n=216). Cheese varieties Variables Sampling sources Metata Ayib Hazo Moisture (g/100 g) DP 38.53±0.69b 78.33±0.69a 77.15±0.55a DC 38.59±1.22b 78.71±1.26a 76.35±1.26a DR 41.27±0.95b 78.49±0.98a 78.18±0.98a Fat (g/100 g) DP 31.89±0.41a 1.42±0.47b 1.43±0.34b DC 30.86±0.91a 1.40±0.86b 1.42±0.62b DR 30.19±0.70a 1.44±0.67b 1.41±0.48b Ash (g/100 g) DP 4.55±0.93a 1.17±0.11b 1.16±0.31b DC 4.57±0.17a 1.16±0.24b 1.15±0.22b DR 4.52±0.13a 1.15±0.14b 1.17±0.12b Crude protein (g/100 g) DP 41.54±6.29a 16.78±0.28b 15.03±2.88b DC 40.82±3.21a 14.59±1.61b 14.94±2.61b DR 41.44±1.24a 14.53±1.24b 14.40±6.24b pH DP 4.18±0.05b 4.49±0.04a 4.44±0.06a DC 4.12±0.15b 4.53±0.14a 4.54±0.16a DR 4.26±0.11b 4.48±0.12a 4.47±0.14a TA (% lactic acid) DP 0.73±0.02a 0.44±0.02b 0.45±0.02b DC 0.72±0.03a 0.43±0.03b 0.44±0.03b DR 0.74±0.02a 0.44±0.02b 0.46±0.02b Note: DP = Dairy producers, DC = Dairy cooperatives, DR = dairy product retail shops and kiosks, TA = Titratable acidity, n = sample size and a,b Means with different superscript letters in a row for each variables under the three sampling sources and cheese varieties are significantly different (P<0.05). The fat, ash and crude protein content of Metata cheese samples were significantly (P<0.05) higher than that of Ayib and Hazo cheese samples collected from different sources (Table 2). However, there was no significant (P>0.05) difference in fat, ash and protein content between Ayib and Hazo cheese samples. The fat content of Metata cheese (30.19 - 31.89 g/100 g) obtained in the present study is slightly higher than the fat content of Metata cheese (28.7±8.4 (g/100 g) reported in Western Gojjam zone of Amhara region, Ethiopia (Eyassu, 2013). However, the fat content of Ayib (1.16-1.52 (g/100 g) reported by Regu et al. (2016) is much lower than Metata Ayib obtained from the present study. The higher fat content of Metata cheese compared to Ayib and Hazo cheese varieties means that it could serve as an important source of energy and essential fatty acids in human nutrition. Fat has many important functions in food; it contributes to the taste, texture and appearance of the cheese (Manson and Willet, 2001). The average ash content of Metata cheese recorded in the present study is similar to the ash content of cheese made from cow milk (4.53%) and buffalo milk (4.67%) (Masud et al., 1992). The higher ash content of Metata Mitiku and Aleme Properties of traditional cheese varieties in Eastern Gojjam 189 cheese compared to Ayib and Hazo cheese varieties might be due to the effect of spices, the reduction of moisture content and absorption of salt by cheese curd during ripening. Metata cheese had more or less similar protein content with the findings of Eyassu (2013) who reported protein content of Metata Ayib to be 43.0±6.9% (g/100 g). The higher protein content of Metata cheese samples might be due to an increase in soluble protein contents during storage as a result of continuous proteolysis of protein and a decrease in moisture content during ripening. The higher crude protein content observed in Metata cheese samples in the present study could serve as an important source of amino acids in human nutrition and its consumption will help to ameliorate protein deficiencies. Cheese contains biologically valuable proteins that are almost 100% digestible, as the ripening phase of the manufacturing process involves a progressive breakdown of caseins to water soluble peptides and free amino acids (Lopez-Expsito et al., 2012). The pH values of Metata cheese samples was significantly (P<0.05) lower than that of Ayib and Hazo cheese samples collected from different sources (Table 2). The pH value observed in the present study is similar with the findings of Kassa (2008) who reported a pH value of 4.34 for Ethiopian traditional cottage cheese (Ayib) samples collected from a local market in Shashemene area, southern Ethiopia. The lower pH values observed in Metata cheese samples might be associated with the fermentation of lactose to lactic acid resulted in reduction of pH and rise in acidity. Cheese pH directly influences chemical changes in the protein network of the cheese curd, with high pH leads to increased interactions among proteins (Floury et al., 2009). The variation in pH values most probably originated from acidifying activities of lactic acid bacteria (LAB) present in cheese (Prodromou et al., 2001). In contrary to this, an increase in pH value may occur during cheese ripening which might be as a result of yeast metabolic activity which uses lactic acid as a source of carbon or a result of great amounts of alkaline compounds released during proteolytic activities (Volken de Souza et al., 2003). The titratable acidity of Metata cheese samples was also significantly (P<0.05) higher than that of Ayib and Hazo cheese samples (Table 2). The present result is not in agreement with the finding of Eyassu (2013) who reported titratable acidity of 0.43±0.07 for Metata cheese samples collected from northwestern Gojjam. The higher titratable acidity observed in Metata cheese samples in the current study might be associated with the growth of lactic acid bacteria that increased the level of lactic acid and consequently resulted in the low pH values of the cheese. Titratable acidity is regulated by the amount of lactose fermented to lactic acid and the buffering capacity of the curd during manufacturing of the cheese (Kafili et al., 2009). Lactobacilli may utilize the residual lactose in cheese during ripening and contribute to increased titratable acidity of the cheese (Arenas et al., 2004). 3.2. Mineral Profile of Metata, Ayib and Hazo Cheese Varieties The mineral contents of Metata, Ayib and Hazo varieties collected from different sources are presented in Table 3. The mineral content of Metata cheese samples was significantly (P<0.05) higher than that of Ayib and Hazo cheese varieties for all the three sampling sources. However, there was no significant (P>0.05) difference observed in mineral content between Ayib and Hazo cheese varieties. The value of phosphorus in Metata cheese samples observed in the current study is in line with the finding of Adetunji and Babalo (2011) who reported phosphorus content of 179 (mg/100 g) for Wara, a traditional West African soft cheese. Phosphorus is the second most abundant mineral in human body with many important biological functions such as acid-base balance, bone and teeth formation, development and maintenance and energy metabolism. (Cashman, 2002). Although phosphorus is the most important structural component of bones and teeth, excessive intake of phosphorus combined with reduced calcium intake may have negative effects on bones (Cashman, 2006). The calcium content of Metata cheese samples observed in the current study is in agreement with the finding of Gonzalez et al. (2009) who reported 50.26±2.30 (mg/100 g) calcium content in semi-hard cheese during six month of ripening period. The higher calcium content of Metata cheese is quite possibly as a result of firmer curd in fermented Metata cheese with higher number of calcium phosphate molecules. Research showed that insufficient intake of calcium raises the risk of obesity (Parikh and Yanovski, 2003), hyperlipidemia and insulin-resistance syndrome (Teegarden, 2003; Zemel, 2004). On the contrary, a diet rich in daily calcium intake enhanced weight reduction in type two diabetic patients (Shahar et al., 2007). Moreover, calcium is responsible for many regulatory functions, such as normal cardiac rhythm maintenance, blood clotting, hormone secretion, muscle contraction and enzyme activation (Cashman, 2002). The magnesium content of Metata cheese samples observed in the current study is in agreement with Kailas and Kapadnis (2015) who reported 49.6 mg/100 g magnesium content of soft cheese samples in Nashik region. Magnesium plays an important role in many physiological processes, such as metabolism of proteins and nucleic acids, neuromuscular transmission and muscle contraction, bone growth and blood pressure regulation (Zamberlin et al., 2012). The sodium content of Metata cheese samples observed in the current study is not in agreement with Mian et al. (2014) who reported 678 (mg/100 g) sodium content for cheddar cheese made from buffalo milk Mitiku and Aleme East African Journal of Sciences Volume 13 (2) 185-194 190 and their mixture with cow milk. The higher values of sodium in Metata cheese samples might be attributed to multiple additions of sodium chloride during the cheese production. Cheese is perceived as containing high levels of sodium, which discourages some consumers from eating cheese (Johnson et al., 2009; Saint-Eve et al., 2009). Consumption of too much sodium is associated with high blood pressure and increased risk of heart attack and stroke (Smith-Spangler et al., 2010; USDA, 2010). The potassium content of Metata cheese samples observed in the current study is in agreement with Slacanac et al. (2011) who reported 202.43±2.44 (mg/100 g) potassium concentration in cheese made from a mixture of Croatian goat and cow milk. The higher value of potassium in Metata cheese samples could be attributed to the release of this mineral from the caseins due to the heat denaturing effect, different processing method employed and the numerous spices used. The high mineral content of Metata cheese is of significant importance from nutritional point of view in that it can be used to combat malnutrition (mineral deficiency) which is prevalent among the general public in developing countries such as Ethiopia. Table 3. The mineral profile of traditional cheese varieties (Mean±SE) (n=216). Cheese varieties Minerals Sampling sources Metata Ayib Hazo Phosphorus (mg/100 g) DP 174.99±1.47a 126.48±1.64b 126.15±2.42b DC 175.68±1.63a 126.74±2.64b 125.22±2.44b DR 175.60±1.02a 125.17±2.04b 124.26±3.04b Calcium (mg/100 g) DP 52.44±2.40a 40.47±0.30b 40.65±0.70b DC 51.46±1.28a 39.68±1.18b 41.73±1.28b DR 52.28±1.99a 41.23±2.99b 43.91±0.99b Magnesium (mg/100 g) DP 43.75±0.36a 8.27±0.36b 8.24±0.26b DC 44.21±0.46a 8.17±0.66b 8.19±0.26b DR 43.59±0.51a 8.29±0.11b 8.12±0.71b Sodium (mg/100 g) DP 338.73±2.34a 42.97±2.64b 41.03±1.65b DC 348.15±4.22a 42.71±4.82b 42.87±3.42b DR 348.36±4.74a 41.88±3.74b 43.60±3.75b Potassium (mg/100 g) DP 200.83±3.34a 81.58±4.33b 80.75±4.54b DC 201.05±1.25a 83.91±4.27b 82.65±4.45b DR 200.31±2.34a 82.66±4.31b 81.28±3.31b Note: DP = Dairy producers, DC = dairy cooperatives, DR = dairy product retail shops and kiosks, n = sample size, a,b Means with the different superscript letters in a row for each mineral under the three sampling sources and cheese varieties are significantly different (P<0.05). 3.3. Sensory Evaluation of Metata, Ayib and Hazo Cheese Varieties Consumer acceptability of Metata, Ayib and Hazo traditional cheese are presented in Table 4. Metata cheese samples had significantly (P<0.05) higher taste, color, aroma, texture, appearance and overall acceptance score than Ayib and Hazo cheese varieties. The average taste score for Metata cheese samples observed in the current study is in agreement with the findings of Regu et al. (2016) who reported that inclusion of one percent garlic powder treated cottage cheese samples had a taste scores of 4.62. The higher taste score of Metata cheese samples observed in the present study could be attributed to various spices added during processing that resulted in strong flavor and acceptable taste. Flavor perception is critically influenced by type of starter culture, level and proteolytic activity of coagulating enzyme, curd washing, ripening condition and rate of curd cooling (Guinee and Kilcawley, 2010). The average color score of Metata cheese samples found in the present study is comparable with the report of Marilda et al. (2013) who reported color score of 4.41 for Marajo cheese manufactured from buffalo milk and cow milk. This might be due to colour change from white to blue mold during ripening of Metata cheese. According to Carpino et al. (2004) cheese color depends on milk fat colour and the content of fat itself. The aroma value of Metata cheese variety observed in the present study is in agreement with the findings of El-Aziz et al. (2012) who reported that cheese made from buffalo milk fortified with ginger extract had the lowest aroma scores. Soryal et al. (2004) reported that the concentrations of free fatty acids mostly short chain fatty acids in cheese significantly influence cheese flavor and aroma. Too much free fatty acid causes a nasty, sour and unpleasant taste to cheese. The higher aroma score in Metata cheese might be attributed to the inherent property of different spices used during Mitiku and Aleme Properties of traditional cheese varieties in Eastern Gojjam 191 processing, which might have imparted pleasant aroma to the cheese. Texture of cheeses is related to a complex interaction between chemical composition and ripening parameters. The differences in moisture content may be the possible reason for the differences in cheese hardness (Anka et al., 2016). Texture is an essential feature of food as it influences processing, handling and shelf life as well as customer preferences for the product (Karadbhajne and Bhoyarkar, 2010). Kumar and Srinivasan (2011) reported that texture of cheese might be affected by water binding capacity due to the nature of protein. However, Karadbhajne and Bhoyarkar (2010) reported that fat, cheese yield, storage period and moisture content as well as coagulants plays an important role in cheese texture. The appearance scores of Metata cheese samples observed in the present study is in agreement with Gehan and Samah (2014) who reported appearance scores of Kareish cheese manufactured by various ways as 4.3-4.7. The overall acceptability of Metata cheese samples observed in the present study agrees with Bandyopadhy et al. (2007) who reported that a Sandash (antioxidant enriched dairy product) fortified with ginger had good acceptability scores. The higher acceptability of Metata cheese might be attributed to the various spices used during its preparation. The high consumer acceptability of Metata cheese is important in that it will facilitate the scaling-up of Metata cheese production to commercial level in the future. Table 4. Consumer acceptability of traditional cheese varieties (Mean ± SE) (n = 58). Cheese varieties Variables Sampling sources Metata Ayib Hazo Taste DP 4.46±0.24a 3.50±0.25b 3.62±0.15b DC 4.48±0.23a 3.48±0.21b 3.58±0.29b DR 4.47±0.17a 3.46±0.37b 3.56±0.37b Color DP 4.56±0.14a 3.65±0.35b 3.58±0.35b DC 4.31±0.29a 3.76±0.19b 3.58±0.24b DR 4.31±0.14a 3.65±0.17b 3.56±0.27b Aroma DP 4.74±0.33a 3.48±0.22b 3.41±0.55b DC 4.85±0.26a 3.45±0.31b 3.44±0.36b DR 4.75±0.15a 3.46±0.45b 3.48±0.42b Texture DP 4.84±0.15a 3.58±0.35b 3.54±0.22b DC 4.86±0.19a 3.54±0.41b 3.55±0.24b DR 4.83±0.17a 3.53±0.27b 3.56±0.33b Appearance DP 4.57±0.37a 3.37±0.21b 3.39±0.45b DC 4.49±0.35a 3.35±0.11b 3.34±0.67b DR 4.47±0.39a 3.38±0.14b 3.36±0.68b Over all acceptability DP 4.27±0.25a 3.53±0.34b 3.51±0.55b DC 4.31±0.39a 3.49±0.48b 3.48±0.65b DR 4.33±0.17a 3.48±0.49b 3.47±0.77b Note: DP = Dairy producers, DC = Dairy cooperatives, DR = dairy product retail shops and kiosks, a, bMeans with the different superscript letters in a row for each variable (sensory attribute) under the three sampling sources and cheese varieties are significantly different (P<0.05), n = Total number of panelists. 4. Conclusions This study we found that Metata cheese variety is rich source of fat and crude protein as well as minerals (calcium, phosphorous, magnesium, sodium and potassium). Moreover, lower moisture content of this cheese variety attributed to its longer shelf life. The consumer acceptability value of Metata cheese variety was also significantly higher than that of Ayib and Hazo cheese varieties. In general Metata cheese variety is highly nutritious and acceptable by the consumer than Ayib and Hazo cheese varieties due to its good gross chemical composition, high-mineral profile and acceptable organoleptic properties. Therefore, nutritional value and acceptability of Metata cheese variety calls for scaling-up of this cheese production to commercial level by developing standardized manufacturing protocols. 5. Acknowledgements The authors are grateful to Ethiopian Institute of Agricultural Research for research grant, Ethiopian Food, Medicines and Health Care Administration and Control Authority, and Bless Agri-food Laboratory Services for providing laboratory facilities for laboratory analyses. Mitiku and Aleme East African Journal of Sciences Volume 13 (2) 185-194 192 6. References Adetunji, V. O. and Babalo, O. O. 2011. A comparative assessment of the nutritional contents of ‘Wara’ a West African soft cheese using calotropis procera and cymbopogon citratusas coagulants. African Journal of food Agriculture Nutrition and Development, 11 (7): 5574- 5585. Anka, P. V., Snezana, P., Anka, K., Marija, J., Milka, P. and Branislava, B. 2016. Production, composition and characteristics of organic hard cheese. Biotechnology in Animal Husbandry, 32 (4): 393-402. Arenas, R., Gonzalez, L., Bernardo, A., Fresno, J. M. and Tornadijo, M. E. 2004. 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