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Using A Double-Pass Solar Drier For Jerky Drying
Available online at www.sciencedirect.com
Energy Procedia
Energy Procedia 00 (2011)30000–000 Energy Procedia (2012) 738 – 744
www.elsevier.com/locate/procedia
SHC 2012
Using a double-pass solar drier for jerky drying Jan Banouta*, Iva Kucerovaª, Stepan Marekª ª Department of Sustainable Technologies, Institute of Tropics and Subtropics, Czech University of Life Sciences Prague, Kamýcká 129, Praha 6 – Suchdol, 16521, Czech Republic
Abstract The double-pass solar drier (DPSD) and standard laboratory oven (LO) were used for drying of jerky from eland (Taurotragus oryx) meat. Instead of traditional jerky marinade a marinade with honey syrup (50% bee honey / 50% distilled water) were used as drying pretreatments in this study. Higher drying rate was observed in DPSD where the reduction of moisture content from initial 72% (w.b.) to desired 30% (w.b.) was achieved after 8 hours instead of LO drying where it took 10 hours. The results also show that best color preservative effect was achieved when the traditional jerky marinade is combined with honey syrup. Finally we can conclude that DPSD is suitable facility for jerky drying and eland meat is one of new potential sources for this kind of popular, shelf-stable and nutrient rich snack.
2012 Published Publishedby byElsevier ElsevierLtd. Ltd.Selection Selection peer-review responsibility of PSE © 2012 andand/or peer-review under under responsibility of the PSE AG AG Keywords: Solar drying; cielab; eland meat; jerky
1. Introduction Advantages of solar driers that enable them to compete with traditional open-air sun drying techniques in developing countries and/or artificial driers powered by energy from fossil fuels have been reported in the literature many times. Therefore preservation of human food such as meat, vegetable, fruit, spices and herbs by solar driers became still more and more popular. Drying meat on the sun is one of the oldest methods of food preservation. It is still a popular method in many developing countries, in particular where no cold chain is available. The fact that dried meat is no longer comparable to fresh meat in terms of appearance and sensory and processing properties, has to be weighed against the significant extension * Corresponding author. Tel.: +420 22438 4186; fax: +420 23438 1829. E-mail address: [email protected]
1876-6102 © 2012 The Authors. Published by Elsevier Ltd. Selection and peer-review under responsibility of the PSE AG doi:10.1016/j.egypro.2012.11.084
2
Jan Banout et al. / Energy Procedia 30 (2012) 738 – 744 J. Banout et al./ Energy Procedia 00 (2011) 000–000
of the shelf-life. Under certain circumstances, in particular in the absence of refrigeration, these disadvantages have to be accepted particularly where the alternative might be loss of the valuable meat by spoilage. Most nutritional properties of meat, in particular the protein content, remain unchanged through drying [1]. Dried meats are traditional in different parts of the world and they are known as ‘‘cecina’’ in Spain, ‘‘biltong’’ in South Africa and ‘‘bresaola’’ in Italy [2]. For instance, in developing countries the consumption of dried meat corresponding to total meat consumption which has been continuously increasing from a modest average annual per capita consumption of 10 kg in the 1960s to 26 kg in 2000 and will reach 37 kg around the year 2030 according to FAO projections [1]. According to the U.S. Department of Agriculture a jerky is classified as a heat-treated and shelf-stable ready-to-eat meat product. Even that a jerky can be made from different animal species more than 70% of jerky is produced from beef meat. Nowadays consumers are increasingly becoming concerned about healthy and safe products and the demand for these products is escalating. Relating to some studies a game meat and venison meets most of the criteria demanded by a discerning consumer. In general a game meat has very low lipid concentrations in muscles. Moreover these lipids are primarily structural lipids with little contribution from triglycerides having a very desirable fatty acid profile. The average fat content of most game species has been recorded to be less than 3 % [3]. One of the perspective venison and/or game animals is eland (Taurotragus oryx). The domestication of eland in Africa for farm production was recommended by FAO [4]. Nowadays the biggest herds of farmed eland might be found in South Africa, however the total number of farms is less than five [3]. Since 2001 there is one experimental herd of domesticated elands on the university farm of the Czech University of Life Sciences Prague (CULS Prague) in Lany (Czech Republic) [5]. The eland is largest kind of antelope comparable to the domestic ox not only in size but also in its placid nature. Its meat is comparable to beef. Further, the eland meat has lower content of intramuscular fat and total fat content is in average around 2.4 % [6]. This fact is important from the meat drying point of view hence higher fat contents in meat decreasing the drying rate. Faith et al. [7] reported, that there is a positive correlation between fat content in dried meat and presence of pathogens where higher fat content meaning higher possibility of pathogen evolution. Thus the main objective of this research was to investigate a forced convection solar drier as facility for jerky production. Further, to investigate new sources for jerky preparation meat samples of eland (Taurotragus oryx) as one of the perspective venison and/or game animals were chosen in this study. 2. Material and methods 2.1. Sample preparation and experimental procedure Fresh eland meat (biceps femoris) purchased form university farm was dried in the Double-pass solar drier (DPSD) designed at Institute of Tropics and Subtropics, Czech University of Life Sciences Prague. Solar drying tests of eland meat were compared with draying in laboratory oven (LO) under constant temperature 50°C. All experiments were carried out at Czech University of Life Sciences Prague (Czech Republic) between June and September 2011. Following draying pretreatment of fresh eland meat were used during all experiments: traditional jerky marinade (TM) with 60ml of soya sauce, 15ml of worcester sauce, 0.6g black pepper, 1.25g of garlic powder, 1.5g of dried onion, 4.35g of smoked salt; traditional marinade with honey (TMH) consist of TM with honey syrup (50% honey / 50% distilled water); fresh meat with no treatment as a control (C). Following operational parameters were measured every hour during solar drying experiments: ambient air temperature (°C), ambient air relative humidity (%), inlet and outlet drying air temperature (°C), inlet and outlet drying air relative humidity (%), drying airflow
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Jan Banout et al. / Energy Procedia 30 (2012) 738 – 744 J. Banout et al. / Energy Procedia 00 (2011) 000–000
rate (m³.h-1), global solar radiation (W.m-2) and weight loss of jerky control samples (g). At the end of each drying test all control samples were collected and dry matter content was estimated by oven method. 2.2. Double-pass solar drier A Double-pass solar drier was designed at the Institute of Tropics and Subtropics, Czech University of Life Sciences Prague, Czech Republic in 2007. The drier is classified as a forced convection indirect type and is based on the known construction of the suspended plate air heating solar collector called “Doublepass”. At the beginning of the drier there are five DC fans which provide the necessary air flow through the absorber and drying chamber. The fans are connected directly to a photovoltaic panel by a parallel connection. No regulatory systems are required as the system regulates the air flow itself due to the position of the sun during the day [8].
Fig. 1. (a) cross-section view of Double-pass solar drier, (b) general view of Double-pass solar drier
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Jan Banout et al. / Energy Procedia 30 (2012) 738 – 744 J. Banout et al./ Energy Procedia 00 (2011) 000–000
4
2.3. Colorimetry To evaluate the effect of used marinades and drying method on jerky samples the color was measured in L* (luminance), a* (red/green) and b* (yellow/blue) chromaticity coordinates using a Color Flex of Hunter Associates Laboratory, Inc., Reston, Virginia, USA. The color was measured by using CIELAB scale at 10° observer and at D65 (Daylight–Neutral) illuminant. 2.4. Sensory evaluation All the sensory analysis was in accordance with international ISO standards. Fifteen panelists were selected and trained. Each panelist evaluated the meat samples submitted on a paper tray designated by digit code. For evaluation was used the profile method and it has been used 100 mm unstructured graphic scale. Evaluated parameters were: general look, general likableness of taste, general likableness of meat taste, intensity of meat taste, intensity of fatty taste, color, texture. 3. Results and discussion Mean drying air temperatures and drying air relative humidity in DPSD was 47.17 ±6.62 °C and 18.91 ±6.24 %. The global solar radiation during all solar drying tests was 21 576 kJ.m-2.day-1. From Fig.2. is evident that higher drying rate was observed in DPSD as compared to LO. 3,00 2,75 C - DPSD
2,50
C - LO
Moisture content (db) kg.kg-1
2,25
TM - DPSD
2,00
TM - LO
1,75
TMH - DPSD
1,50
TMH - LO
1,25 1,00 0,75 0,50
0,25 0,00 1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
Drying time, (h)
Fig. 2. Variation of moisture content of jerky samples according to drying pretreatment in DPSD and LO
The initial moisture content of all samples was 72% while the desired moisture around 30% w.b. estimated as optimal for beef jerky was achieved after 8 and 10 hours of drying in DPSD and LO, respectively. Fig.3. also shows significant influence of each marinade on the drying kinetics mainly during falling rate period. The Tab.1. shows an effect of each marinade and type of drying unit on the final color of dried eland jerky.
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Jan Banout et al. / Energy Procedia 30 (2012) 738 – 744 J. Banout et al. / Energy Procedia 00 (2011) 000–000
5
Table 1. Effect of drying pretreatment and drying facility on color properties of eland jerky samples (n = 20)
CIELab color L (D65) a (D65) b (D65)
DPSD TM 20.65a ±2.74 2.11c ±0.74 6.03a ±1.51
C 30.24b ±4.30 5.07d ±0.93 9.27b ±2.19
TMH 21.21a ±3.50 1.44a ±0.56 4.75a ±1.14
C 29.98b ±3.61 3.14b ±1.04 5.17a ±3.10
LO TM 28.80b ±3.51 3.31b ±1.30 10.46b ±3.19
TMH 20.04a ±2.31 1.26a ±0.87 6.20a ±1.39
Means in the same rows with different letters as superscripts are significantly different by Duncan’s Multiple Range Test (p˂ 0.05).
From the results in Tab.1. is evident that in case of TMH the CIELab data shows no statistically significant differences between samples from DPSD and LO. This fact could be interpreted as strongest color preservative effect in case of TMH as compared to other pretreatments where the final color was more or less affected by used drying technique. Fig.3. shows results from first sensory evaluation where only control (C) samples dried in DPSD and LO were evaluated by 15 member panel. Values are averages and expressed as % of graphic scale. Tab.2. represent evaluated parameters and orientation of each parameter. Table 2. Parameters and orientation Parameter / Orientation General look 80
Intensity of aftertastes
60
General likableness of taste General likableness of meat taste
40
General structure
20 0
Sappiness Fibrousness
Intensity of meat taste Intensity of fatty taste
Masticability
Hardness
0
100
like
dislike
like
dislike
Intensity of fatty taste
like slightly intensive slightly intensive
dislike extremely intensive extremely intensive
Hardness
General look General likableness of taste General likableness of meat taste Intensity of meat taste
very soft
very hard
Masticability
bad
very gut
Fibrousness
soft
chewy
Sappiness
dry
juicy
bad slightly intensive
excellent Extremely intensive
General structure C in DPSD
C in LO
Intensity of aftertastes
Fig. 3. Sensory evaluation of C samples in DPSD and LO
First sensory evaluation of 15 member panel shows that effect of drying method on the evaluation of control (C) samples was not statistically significant. Overall, between C samples there were not significant differences and on a clear statistical conclusion would require more evaluation. Second sensory evaluation of 10 panelists evaluated TM and TMH samples in DPSD. From the results in Fig.4. is evident, that TMH samples have better evaluation of likableness of color.
Banoutetetal.al./ EnergyProcedia Procedia3000(2012) (2011)738 000–000 Jan J.Banout / Energy – 744
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Table 3. Parameters and orientation Parameter / Orientation
General structure Sappiness
General look 80 60
General likableness of taste General likableness of meat taste
40
Intensity of meat taste
20 Fibrousness
General look General likableness of taste General likableness of meat taste
Intensity of meat taste
0
Intensity of fatty taste Intensity of color
Masticability
Intensity of fatty taste
Hardness
Intensity of colour Likableness of colour
TM
TMH
Likableness of color Hardness
0
100
like
dislike
like
dislike
like slightly intensive slightly intensive
dislike extremely intensive extremely intensive
light
dark
like
dislike
very soft
very hard
Masticability
bad
very gut
Fibrousness
soft
chewy
Sappiness
dry
juicy
General structure
bad
excellent
Fig. 4. Sensory evaluation of TM and TMH samples in DPSD
4. Conclusion Drying experiments carried out during this study shows no significant difference between drying process in LO and DPSD. Similar results have been reached in case of product quality evaluation by colorimetry and sensory analyses. Highest color preservative effect was observed in case of combination of traditional marinade with honey as the drying pretreatment during the jerky production. As a conclusion we consider a DPSD as suitable facility for jerky drying and eland meat as one of new potential sources for this kind of popular, shelf-stable and nutrient rich snack. Acknowledgements This research was financially supported by the Ministry of Education, Youth and Sports by the Fund for Development of Universities (Project No. 51130/ 1161/ 51/ 1602).
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Jan Banout et al. / Energy Procedia 30 (2012) 738 – 744 J. Banout et al. / Energy Procedia 00 (2011) 000–000
References [1] Heinz G, Hautzinger P. Meat Processing Technology for Small-to medium scale producers. FAO Regional Office for Asia and the Pacific (RAP), Bankong; 2007. [2] Hierroa E, de la Hoza L, Ordoňez JA. Headspace volatile compounds from salted and occasionally smoked dried meats (cecinas) as affected by animal species. Food Chemistry; 2004; 85: 649–657. [3] Hoffman LC, Wiklund E. Game and venison – meat for the modern consumer. Meat Science; 2006; 74:197–208. [4] Scherf DB. World Watch List for domestic animal diversity, FAO, Roma; 2000; p.726. [5] Kotrba R, Ščevlíková P. The evaluation of antelope breeding and the proposal of the economic use in the Czech Republic. Agricultura tropica et subtropica ; 2002 ; 35: 129-137. [6] La Chevallerie M, Erasmus JM, Skinner JD, van Zyl JHM. A note on the carcass composition of the Common Eland (Taurotragus oryx). S. Afr. J. Anim. Sci. ; 1971; 1:129-131. [7] Faith NG, Le Coutour NS, Alvarenga MB, Calicoglu M, Buege DR, Luchansky JB. Viability of Escherichia. coli O157:H7 in ground and formed beef jerky prepared at levels of 5 and 20% fat and dried at 52, 57, 63, or 68°C in a home-style dehydrator. International Journal of Food Microbiology; 1998; 41: 213–221. [8] Banout J, et al. Design and performance evaluation of a Double-pass solar drier for drying of red chilli (Capsicum annum L.). Solar Energy; 2011; 85: 506515.
7
Energy Procedia
Energy Procedia 00 (2011)30000–000 Energy Procedia (2012) 738 – 744
www.elsevier.com/locate/procedia
SHC 2012
Using a double-pass solar drier for jerky drying Jan Banouta*, Iva Kucerovaª, Stepan Marekª ª Department of Sustainable Technologies, Institute of Tropics and Subtropics, Czech University of Life Sciences Prague, Kamýcká 129, Praha 6 – Suchdol, 16521, Czech Republic
Abstract The double-pass solar drier (DPSD) and standard laboratory oven (LO) were used for drying of jerky from eland (Taurotragus oryx) meat. Instead of traditional jerky marinade a marinade with honey syrup (50% bee honey / 50% distilled water) were used as drying pretreatments in this study. Higher drying rate was observed in DPSD where the reduction of moisture content from initial 72% (w.b.) to desired 30% (w.b.) was achieved after 8 hours instead of LO drying where it took 10 hours. The results also show that best color preservative effect was achieved when the traditional jerky marinade is combined with honey syrup. Finally we can conclude that DPSD is suitable facility for jerky drying and eland meat is one of new potential sources for this kind of popular, shelf-stable and nutrient rich snack.
2012 Published Publishedby byElsevier ElsevierLtd. Ltd.Selection Selection peer-review responsibility of PSE © 2012 andand/or peer-review under under responsibility of the PSE AG AG Keywords: Solar drying; cielab; eland meat; jerky
1. Introduction Advantages of solar driers that enable them to compete with traditional open-air sun drying techniques in developing countries and/or artificial driers powered by energy from fossil fuels have been reported in the literature many times. Therefore preservation of human food such as meat, vegetable, fruit, spices and herbs by solar driers became still more and more popular. Drying meat on the sun is one of the oldest methods of food preservation. It is still a popular method in many developing countries, in particular where no cold chain is available. The fact that dried meat is no longer comparable to fresh meat in terms of appearance and sensory and processing properties, has to be weighed against the significant extension * Corresponding author. Tel.: +420 22438 4186; fax: +420 23438 1829. E-mail address: [email protected]
1876-6102 © 2012 The Authors. Published by Elsevier Ltd. Selection and peer-review under responsibility of the PSE AG doi:10.1016/j.egypro.2012.11.084
2
Jan Banout et al. / Energy Procedia 30 (2012) 738 – 744 J. Banout et al./ Energy Procedia 00 (2011) 000–000
of the shelf-life. Under certain circumstances, in particular in the absence of refrigeration, these disadvantages have to be accepted particularly where the alternative might be loss of the valuable meat by spoilage. Most nutritional properties of meat, in particular the protein content, remain unchanged through drying [1]. Dried meats are traditional in different parts of the world and they are known as ‘‘cecina’’ in Spain, ‘‘biltong’’ in South Africa and ‘‘bresaola’’ in Italy [2]. For instance, in developing countries the consumption of dried meat corresponding to total meat consumption which has been continuously increasing from a modest average annual per capita consumption of 10 kg in the 1960s to 26 kg in 2000 and will reach 37 kg around the year 2030 according to FAO projections [1]. According to the U.S. Department of Agriculture a jerky is classified as a heat-treated and shelf-stable ready-to-eat meat product. Even that a jerky can be made from different animal species more than 70% of jerky is produced from beef meat. Nowadays consumers are increasingly becoming concerned about healthy and safe products and the demand for these products is escalating. Relating to some studies a game meat and venison meets most of the criteria demanded by a discerning consumer. In general a game meat has very low lipid concentrations in muscles. Moreover these lipids are primarily structural lipids with little contribution from triglycerides having a very desirable fatty acid profile. The average fat content of most game species has been recorded to be less than 3 % [3]. One of the perspective venison and/or game animals is eland (Taurotragus oryx). The domestication of eland in Africa for farm production was recommended by FAO [4]. Nowadays the biggest herds of farmed eland might be found in South Africa, however the total number of farms is less than five [3]. Since 2001 there is one experimental herd of domesticated elands on the university farm of the Czech University of Life Sciences Prague (CULS Prague) in Lany (Czech Republic) [5]. The eland is largest kind of antelope comparable to the domestic ox not only in size but also in its placid nature. Its meat is comparable to beef. Further, the eland meat has lower content of intramuscular fat and total fat content is in average around 2.4 % [6]. This fact is important from the meat drying point of view hence higher fat contents in meat decreasing the drying rate. Faith et al. [7] reported, that there is a positive correlation between fat content in dried meat and presence of pathogens where higher fat content meaning higher possibility of pathogen evolution. Thus the main objective of this research was to investigate a forced convection solar drier as facility for jerky production. Further, to investigate new sources for jerky preparation meat samples of eland (Taurotragus oryx) as one of the perspective venison and/or game animals were chosen in this study. 2. Material and methods 2.1. Sample preparation and experimental procedure Fresh eland meat (biceps femoris) purchased form university farm was dried in the Double-pass solar drier (DPSD) designed at Institute of Tropics and Subtropics, Czech University of Life Sciences Prague. Solar drying tests of eland meat were compared with draying in laboratory oven (LO) under constant temperature 50°C. All experiments were carried out at Czech University of Life Sciences Prague (Czech Republic) between June and September 2011. Following draying pretreatment of fresh eland meat were used during all experiments: traditional jerky marinade (TM) with 60ml of soya sauce, 15ml of worcester sauce, 0.6g black pepper, 1.25g of garlic powder, 1.5g of dried onion, 4.35g of smoked salt; traditional marinade with honey (TMH) consist of TM with honey syrup (50% honey / 50% distilled water); fresh meat with no treatment as a control (C). Following operational parameters were measured every hour during solar drying experiments: ambient air temperature (°C), ambient air relative humidity (%), inlet and outlet drying air temperature (°C), inlet and outlet drying air relative humidity (%), drying airflow
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Jan Banout et al. / Energy Procedia 30 (2012) 738 – 744 J. Banout et al. / Energy Procedia 00 (2011) 000–000
rate (m³.h-1), global solar radiation (W.m-2) and weight loss of jerky control samples (g). At the end of each drying test all control samples were collected and dry matter content was estimated by oven method. 2.2. Double-pass solar drier A Double-pass solar drier was designed at the Institute of Tropics and Subtropics, Czech University of Life Sciences Prague, Czech Republic in 2007. The drier is classified as a forced convection indirect type and is based on the known construction of the suspended plate air heating solar collector called “Doublepass”. At the beginning of the drier there are five DC fans which provide the necessary air flow through the absorber and drying chamber. The fans are connected directly to a photovoltaic panel by a parallel connection. No regulatory systems are required as the system regulates the air flow itself due to the position of the sun during the day [8].
Fig. 1. (a) cross-section view of Double-pass solar drier, (b) general view of Double-pass solar drier
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Jan Banout et al. / Energy Procedia 30 (2012) 738 – 744 J. Banout et al./ Energy Procedia 00 (2011) 000–000
4
2.3. Colorimetry To evaluate the effect of used marinades and drying method on jerky samples the color was measured in L* (luminance), a* (red/green) and b* (yellow/blue) chromaticity coordinates using a Color Flex of Hunter Associates Laboratory, Inc., Reston, Virginia, USA. The color was measured by using CIELAB scale at 10° observer and at D65 (Daylight–Neutral) illuminant. 2.4. Sensory evaluation All the sensory analysis was in accordance with international ISO standards. Fifteen panelists were selected and trained. Each panelist evaluated the meat samples submitted on a paper tray designated by digit code. For evaluation was used the profile method and it has been used 100 mm unstructured graphic scale. Evaluated parameters were: general look, general likableness of taste, general likableness of meat taste, intensity of meat taste, intensity of fatty taste, color, texture. 3. Results and discussion Mean drying air temperatures and drying air relative humidity in DPSD was 47.17 ±6.62 °C and 18.91 ±6.24 %. The global solar radiation during all solar drying tests was 21 576 kJ.m-2.day-1. From Fig.2. is evident that higher drying rate was observed in DPSD as compared to LO. 3,00 2,75 C - DPSD
2,50
C - LO
Moisture content (db) kg.kg-1
2,25
TM - DPSD
2,00
TM - LO
1,75
TMH - DPSD
1,50
TMH - LO
1,25 1,00 0,75 0,50
0,25 0,00 1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
Drying time, (h)
Fig. 2. Variation of moisture content of jerky samples according to drying pretreatment in DPSD and LO
The initial moisture content of all samples was 72% while the desired moisture around 30% w.b. estimated as optimal for beef jerky was achieved after 8 and 10 hours of drying in DPSD and LO, respectively. Fig.3. also shows significant influence of each marinade on the drying kinetics mainly during falling rate period. The Tab.1. shows an effect of each marinade and type of drying unit on the final color of dried eland jerky.
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Jan Banout et al. / Energy Procedia 30 (2012) 738 – 744 J. Banout et al. / Energy Procedia 00 (2011) 000–000
5
Table 1. Effect of drying pretreatment and drying facility on color properties of eland jerky samples (n = 20)
CIELab color L (D65) a (D65) b (D65)
DPSD TM 20.65a ±2.74 2.11c ±0.74 6.03a ±1.51
C 30.24b ±4.30 5.07d ±0.93 9.27b ±2.19
TMH 21.21a ±3.50 1.44a ±0.56 4.75a ±1.14
C 29.98b ±3.61 3.14b ±1.04 5.17a ±3.10
LO TM 28.80b ±3.51 3.31b ±1.30 10.46b ±3.19
TMH 20.04a ±2.31 1.26a ±0.87 6.20a ±1.39
Means in the same rows with different letters as superscripts are significantly different by Duncan’s Multiple Range Test (p˂ 0.05).
From the results in Tab.1. is evident that in case of TMH the CIELab data shows no statistically significant differences between samples from DPSD and LO. This fact could be interpreted as strongest color preservative effect in case of TMH as compared to other pretreatments where the final color was more or less affected by used drying technique. Fig.3. shows results from first sensory evaluation where only control (C) samples dried in DPSD and LO were evaluated by 15 member panel. Values are averages and expressed as % of graphic scale. Tab.2. represent evaluated parameters and orientation of each parameter. Table 2. Parameters and orientation Parameter / Orientation General look 80
Intensity of aftertastes
60
General likableness of taste General likableness of meat taste
40
General structure
20 0
Sappiness Fibrousness
Intensity of meat taste Intensity of fatty taste
Masticability
Hardness
0
100
like
dislike
like
dislike
Intensity of fatty taste
like slightly intensive slightly intensive
dislike extremely intensive extremely intensive
Hardness
General look General likableness of taste General likableness of meat taste Intensity of meat taste
very soft
very hard
Masticability
bad
very gut
Fibrousness
soft
chewy
Sappiness
dry
juicy
bad slightly intensive
excellent Extremely intensive
General structure C in DPSD
C in LO
Intensity of aftertastes
Fig. 3. Sensory evaluation of C samples in DPSD and LO
First sensory evaluation of 15 member panel shows that effect of drying method on the evaluation of control (C) samples was not statistically significant. Overall, between C samples there were not significant differences and on a clear statistical conclusion would require more evaluation. Second sensory evaluation of 10 panelists evaluated TM and TMH samples in DPSD. From the results in Fig.4. is evident, that TMH samples have better evaluation of likableness of color.
Banoutetetal.al./ EnergyProcedia Procedia3000(2012) (2011)738 000–000 Jan J.Banout / Energy – 744
6
743
Table 3. Parameters and orientation Parameter / Orientation
General structure Sappiness
General look 80 60
General likableness of taste General likableness of meat taste
40
Intensity of meat taste
20 Fibrousness
General look General likableness of taste General likableness of meat taste
Intensity of meat taste
0
Intensity of fatty taste Intensity of color
Masticability
Intensity of fatty taste
Hardness
Intensity of colour Likableness of colour
TM
TMH
Likableness of color Hardness
0
100
like
dislike
like
dislike
like slightly intensive slightly intensive
dislike extremely intensive extremely intensive
light
dark
like
dislike
very soft
very hard
Masticability
bad
very gut
Fibrousness
soft
chewy
Sappiness
dry
juicy
General structure
bad
excellent
Fig. 4. Sensory evaluation of TM and TMH samples in DPSD
4. Conclusion Drying experiments carried out during this study shows no significant difference between drying process in LO and DPSD. Similar results have been reached in case of product quality evaluation by colorimetry and sensory analyses. Highest color preservative effect was observed in case of combination of traditional marinade with honey as the drying pretreatment during the jerky production. As a conclusion we consider a DPSD as suitable facility for jerky drying and eland meat as one of new potential sources for this kind of popular, shelf-stable and nutrient rich snack. Acknowledgements This research was financially supported by the Ministry of Education, Youth and Sports by the Fund for Development of Universities (Project No. 51130/ 1161/ 51/ 1602).
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