effect of green tea, stinging nettle and olive leaves

Journal of Food Processing and Preservation ISSN 1745-4549

EFFECT OF GREEN TEA, STINGING NETTLE AND OLIVE LEAVES EXTRACTS ON THE QUALITY AND SHELF LIFE STABILITY OF FRANKFURTER TYPE SAUSAGE KAZEM ALIREZALU1, JAVAD HESARI1,5, MOHAMMAD HADI ESKANDARI2, HADI VALIZADEH3 and MOHAMMAD SIROUSAZAR4 1

Department of Food Science and Technology, Faculty of Agriculture, University of Tabriz, Tabriz, Iran Department of Food Science and Technology, Faculty of Agriculture, Shiraz University, Shiraz, Iran 3 Department of Pharmaceutics, Drug Applied Research Center and Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran 4 Faculty of Chemical Engineering, Urmia University of Technology, Urmia, Iran 2

5 Corresponding author. TEL: 198-413-3392053; FAX: 198-413-3345332; EMAIL: [email protected]

Received for Publication January 18, 2016 Accepted for Publication April 30, 2016

doi:10.1111/jfpp.13100

ABSTRACT The effects of green tea (GTE), stinging nettle (SNE) and olive leaves (OLE) extracts on physicochemical, microbiological, texture and sensory properties of Frankfurter type sausage were investigated during 45 days of storage at 4C. Results indicated that pH, aw value, phenolic compounds and color values (L* and a* values) decreased during storage. Samples incorporated with 500 ppm GTE showed the lowest TBARS value compared to SNE, OLE and control sausage. Plant extracts reduced the count of total viable bacteria, mold and yeast by at least 2 log cfu/g. The addition of OLE increased significantly the maximum compression force compared with other samples. Sausage incorporated with SNE had the highest sensory score regarding flavor, freshness odor and overall acceptability. Based on the results, sausage incorporated with plant extracts could have a significant impact to improve quality benefits, color stability and shelf life of Frankfurter type sausage.

PRACTICAL APPLICATION Food decay by spoilage microorganisms and chemical activities causes considerable economic losses and constitutes a health risk for consumers. Although chemical preservatives can effectively be used in meat products to control spoilage, foodborne pathogenic microorganisms and lipid oxidation, whereas there are significant concerns related to their toxicological aspects. Plant extracts are rich in potentially bioactive compounds, antimicrobial and antioxidant ingredients. The addition of natural ingredients such as green tea, stinging nettle and olive leaves extracts to Frankfurter type sausage could provide functional components to improve the healthier properties, sensory attributes and shelf life extension of novel meat products.

INTRODUCTION Meat and meat products are very important sources of essential amino acids, minerals and vitamins (Biesalski 2005). In recent years, demand for functional and healthier meat and meat products with reduced content of fat, decreased levels of nitrite and sodium chloride, modified composition of fatty acid profile and incorporated health enhancing ingredients such as plant extracts are rapidly

increasing world-wide (Zhang et al. 2010). Frankfurter type sausage is popular meat product enjoyed by millions of consumers. However, an increased concern about its shelf life and nutritional quality has led the food industry to develop new meat product formulations (Feiner 2006; Baka et al. 2015). Although synthetic antioxidants due to low cost, high stability and efficiency can effectively be used in meat product, whereas there are significant concerns related to their

C 2016 Wiley Periodicals, Inc. Journal of Food Processing and Preservation 00 (2016) 00–00 V

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EFFECT OF PLANT EXTRACTS IN FRANKFURTER SAUSAGE

K. ALIREZALU ET AL.

toxicological aspects. Therefore, extensive research has been performed to employ natural antioxidants and antimicrobial such as plant extracts as alternatives to synthetic antioxidants (Tang et al. 2001). Green tea (Camellia sinensis L.) is a widely consumed beverage that has attracted much attention in recent years due to its numerous health and functional benefits such as antimicrobial activity, antioxidant capacity, anticarcinogenic and antiarteriosclerotic aspects (Cooper et al. 2005). Catechins are the most important group of polyphenols present in green tea leaves composed of epicatechin, epigallocatechin, epicatechin gallate and epigallocatechin gallate (Zhong et al. 2009). It has been reported that green tea extract (GTE) have inhibitory effects on foodborne pathogens and spoilage bacteria such as Campylobacter jejuni, Staphylococcus aureus, Escherichia coli, Listeria monocytogenes, Salmonella typhi, Vibrio parahaemolyticus, Bacillus cereus, Pleisomonas shigelloides, Clostridium perfringens and Pseudomonas fluorescens (Toda et al. 1989; Diker et al. 1991; Chou et al. 1999; Sakanaka et al. 2000; Taguri et al. 2004; Mbata et al. 2008). Takabayashi et al. (2004) found that GTE also have an inhibitory effect on Helicobacter pylori infection. Numerous technological studies have reported that the GTE to be a potential antioxidant capacity as well as antimicrobial activity in meat products (Tang et al. 2001; Mitsumoto et al. 2005). Olive leaves (Olea europaea L.) extract (OLE) contains phenolic compound which is known to have antioxidative, antimicrobial, antiinflammatory and antiviral aspects (Pereira et al. 2007; Medina et al. 2013; Talhaoui et al. 2015). It has been proved that OLE protects low-density lipoprotein from oxidation, decrease the blood pressure in animals and inhibits the lipid oxidation (Khayyal et al. 2002; Micol et al. 2005; Bouaziz et al. 2008). In addition, antiinflammatory, antiviral and neuroprotective properties of the OLE have been report by Omar (2010). Stinging nettle (Urtica dioica L.) is traditionally used as a purgative, expectorant, haemostatic, diuretic and vermifuge, as well as for the treatment of cancer, rheumatism, eczema, haemorrhoids, hyperthyroidism and bronchitis (Sezik et al. 2001). Stinging nettle is mainly used in the pharmaceutical industry due to its antiviral characteristics. Manganelli et al. (2005) claimed that stinging nettle had a strong inhibitory effect on infected cells by HIV. Stinging nettle extract (SNE) is a natural antimicrobial agent and phenolic antioxidant and has been shown to significantly reduce lipid oxidation in sucuk (Turkish dry-fermented sausage) and model systems (Aksu 2003; Exarchou et al. 2006) and decrease microbial count in sucuk (Aksu and Kaya 2004). Martinez et al. (2006) reported that the addition of stinging nettle extract into the fresh pork sausage not only improved the healthier compounds, essential amino acids, ascorbic acid and minerals especially Fe, but also effectively reduced 2

microbial count. Previously published data have been reported SNE had more antioxidant activity than BHA, quercetin and a-tocoferrol and also had antimicrobial activity on various bacteria in vitro (G€ ulçin et al. 2004). Nowadays, many studies have been carried out to develop natural ingredients for use as antibacterial agents and antioxidants to design an increased shelf life of meat products (Choi and Chin 2003; Sebranek and Bacus 2007; Zarringhalami et al. 2009; Eskandari et al. 2013). Therefore, the aim of the present study was to determine the effect of green tea, stinging nettle and olive leaves extracts on the microbial status and quality of Frankfurter type sausage during refrigerated storage.

MATERIALS AND METHODS Preparation of Plant Extract Plant extracts were prepared from the grounded green tea, stinging nettle and olive leaves according to the method reported by Ebrahimzadeh et al. (2008), with some modifications as followed. Briefly, leaves were dried (48 h at 40C), then ground and sifted through a 14 in. sieve. Fifty grams of the plant material was added to Erlenmeyer flask containing the 500 mL of ethanol 95% solution (475 mL ethanol 99.95% and 25 mL distilled water) and mixed by magnetic stirrer for 48 h. After filtering (Whatman No. 1) solution, ethanol was evaporated by rotary evaporator at 40C. Plant extracts in 500 ppm concentration were used to produce the functional sausage.

Frankfurter Type Sausage Manufacture and Sampling Different types of Frankfurter type sausage incorporating with green tea (GTE), stinging nettle (SNE) and olive leaves (OLE) extracts were prepared by a local meat processing plant. Based on the previously obtained results, functional sausage incorporated with 500 ppm plant extract had the highest shelf life and sensory properties. Frankfurter type sausages were prepared using a common recipe (control) or the same recipe but incorporated with GTE, SNE and OLE (500 ppm). All treatments, about 2 kg each, were replicated from a separate beef meat source as three different productions. The following raw materials and ingredients were assigned (g/kg) of beef meat (550), vegetable oil (120) ice/ water (210), salt (15), seasoning (20), starch and other dry materials (81.5), sodium polyphosphate (3.5), sodium ascorbate (0.4) and sodium nitrite (0.012). The meat was chopped into cubes approximately 3 mm and ground in a commercial food grinder (Mado, Germany). Afterward, the minced meat was homogenized with half of the ice/extract


K. ALIREZALU ET AL.

(GTE, SNE and OLE), NaCl and sodium polyphosphate in a cutter (Kilia EX3000 RS, Germany) for 12 min at 10C. Then, starch, seasoning, sodium nitrite, sodium ascorbate and other dried ingredients were slowly added and the mixture was homogenized for 1 min. finally, the remaining half of ice/extract and other remaining ingredients were added and mixed about 2 min until the meat emulsion reached 14C. The emulsion was mechanically stuffed (Handtmann VF50, Germany) into polyamide casings (28 mm diameter). Sausages were cooked by steam at 80–85C for 90 min to an internal temperature of 72C. After steam cooking, samples were immediately chilled with cold water shower and stored under refrigeration (4C) for 45 days. Physicochemical, microbiological, texture and sensory properties of sausage samples were analyzed on the 1th, 15th, 30th and 45th days of the storage.

Proximate Composition and pH The pH was measured after homogenization of samples with distilled water at a ratio of 1:10 using a pH-meter (Hanna, Methrom, Switzerland). The level of moisture, fat, protein and ash was determined according to the methods of AOAC (1995). Determination of water activity (aw) was carried out using a Water Activity System apparatus (Rotronic HP23-AW).


were vortexed, held for 1 h and the absorbance determined at 700 nm using a UV-vis spectrophotometer Hitachi U3210 (Hitachi, Ltd., Tokyo, Japan). Gallic acid was used as the standard curve and regression measured as Y 5 0.9575X 2 0.0689 (R2 5 0.9702), where Y represents concentration of the total phenol contents of the solution (mg/mL) and X represents absorbance rate. Results were expressed as mg of gallic acid (GA)/100 g dry weight.

Determination of Color Values A simple digital imaging method was used for analyzing color of surfaces of the samples (L*: lightness, a*: redness and b*: yellowness) according to the method described (Leon et al. 2006). Sausages were sliced in 25 3 25 3 10 mm thickness. A high-resolution digital camera (8 mega-pixels) was used to determination internal and external surface color by capturing the color image of the sausages under proper lighting at room temperature (20C) in triplicate. The angle between the lighting source axis and the camera lens axis was around 458. Photoshop software was used to convert RGB ! L*a*b* values of the sausage samples. The instrument was calibrated with standard plates before analysis.

Microbiological Analysis Lipid Oxidation As lipid oxidation index, 2-thiobarbituric acid reactive substances assay (TBARS) was determined using a spectrophotometer (UV 2100, Unico Scientific Instruments, NJ) according by Faustman et al. (1992). Briefly, Frankfurter type sausage (10 g) was homogenized with 25 mL of 20% trichloroacetic acid (TCA) and 20 mL distilled water in a blender for 30 s at high speed. The mixture was centrifuged at 1,000 3 g for 20 min and the resulting supernatant was filtered through filter paper (Whatman No. 1). Two milliliters of 0.02 M aqueous 2-thiobarbituric acid was added to 2 mL of the filtrate in a test tube. The tube was heated in a boiling water bath for 20 min and then cooled in tap water for 5 min. Absorbance was measured at 532 nm and lipid oxidation was reported as mg malondialdehyde/kg sausage.

Twenty five grams of Frankfurter type sausage was homogenized in 225 mL of 0.1% peptone water for 3 min using a sterile bag blender (Neutec; Paddle Lab Blender, USA). Serial dilutions were then made with the same diluent. Plate count agar (PCA, Merck, Darmstadt, Germany) and violet red bile agar (VRB Agar, Merck) were used for enumeration of total viable count and coliform, respectively, using the pour plate method to enumerate bacteria. Total viable count and coliform were incubated at 30C for 48–72 h and 37C for 24 h, respectively. For mold and yeast count, samples were spread-plated on dichloran rose-bengal chloramphenicol agar (DRBC Agar, Merck) and incubated at 25C for 5 days. Microbial count was expressed as log10 colony forming units (cfu) per g of sausage (FDA 2013).

Total Phenolic Content

Texture Measurement

The total phenolic content of sausage samples was determined colorimetrically, using the Folin–Ciocalteau (F–C) reagent (Liu et al. 2009). Briefly, about 50 g of ground frankfurter type sausage were mixed with 100 mL boiled distilled water and left for 20 min. After cooling and filtering, 2.5 mL of F–C reagent and 5 mL of saturated sodium carbonate solution were added to each sample in a test tube. The tubes

The maximum compression force was measured on the 30th days of the storage as reported by Thiagu et al. (1993). Sausages were sliced in 25 3 25 3 25 mm thickness. The test was carried out at a crosshead speed of 50 mm/min to compress the center of sample to 50% of its original height by an Instron Universal Testing Machine (Model 1140) using a flat end cylindrical probe (diameter 30 mm).


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K. ALIREZALU ET AL.

TABLE 1. CHEMICAL COMPOSITION OF SAUSAGE INCORPORATED WITH PLANT EXTRACTS Properties (%) Treatment Control GTE SNE OLE

Moisture

Fat a

59.67 6 0.21 60.36 6 0.45a 61.25 6 0.36a 60.83 6 0.37a

Protein a

18.28 6 0.42 18.36 6 0.41a 17.99 6 0.53a 17.48 6 0.33a

Ash a

13.74 6 0.09 13.33 6 0.64a 13.69 6 0.23a 13.96 6 0.31a

2.58 6 0.15a 2.65 6 0.24a 2.74 6 0.18a 2.79 6 0.32a

* No significance within each column (P > 0.05).

Sensory Evaluation The effect of different plant extracts on the sensory properties of Frankfurter type sausage was evaluated by twelve experienced panelists (eight females, four males) who were familiar with the Frankfurter type sausage. On the descriptive scale, intensity of appearance color, flavor, freshness odor and texture attributes were determined on a five-point scale where “5” corresponded to “very strong” and “0” corresponded to “none.” The overall acceptability was obtained as the sum of the attributes scores (Stone and Sidel 2004; Economou et al. 2009).

Statistical Analysis Data were submitted to an analysis of variance according to a repeated measures experimental design with the MIXED procedure of the statistical analysis software. Least square means was used to determine the groups significantly different from each other. A completely random design was used for moisture, fat, protein, ash content, texture and sensory properties. Comparisons of mean values were made using Duncan’s multiple range tests. A P < 0.05 was considered to indicate statistical significance. All data were determined in triplicate and are reported as means and standard errors of means.

2009) where no significant effect in gross composition was recorded. Sallama et al. (2004) found that addition of the different garlic forms did not cause any significant changes in moisture, protein and fat contents. Results indicated that aw value were not significantly (P > 0.05) affected by the addition of plant extracts and storage period (Fig. 1). The effect of teak leaf extract (Tectona grandis) and storage on aw value over time has been previously reported in beef sausages (Arief et al. 2014). The pH of sausage samples was significantly (P < 0.05) affected by the addition of plant extracts during storage period (Table 2). The pH of the sausage samples decreased slightly at the first of storage period, due to addition of plant extracts and this could be attributed to the acidic pH of the extracts (Ibrahim et al. 2012). In all sausage samples, pH decreased significantly (P < 0.05) from 6.51 to 5.24 which could be due to production of organic acids by bacteria. There is significant differences (P < 0.05) on pH of Frankfurter type sausages incorporated with plant extract and control sausage. In the other words, pH for sausage incorporated with SNE had significantly (P < 0.05) the highest amount of pH after 45 days storage. Results showed that pH for all treatments were within the accepted range during storage period. These results were in agreement with literature that pH of sausage decreased gradually during storage (Georgantelis et al. 2007). Hayes et al. (2010a) revealed that the pH of raw beef

RESULTS AND DISCUSSION Effect of Adding Plant Extracts on Proximate Composition and pH Similar moisture (59.67–61.25%), fat (17.48–18.36%), protein (13.33–13.96%) and ash (2.58–2.79%) contents for Frankfurter type sausages incorporating GTE, SNE and OLE were achieved. The addition of plant extract had no significant effect (P > 0.05) on moisture, fat, protein and ash contents in sausage samples (Table 1). The results of the present study are in agreement with other research performed on raw and cooked pork sausages incorporated with olive leaf extract, sesamol, lutein and ellagic acid (Hayes et al. 2010b, 2011) and on fresh chicken sausages with rosemary and Chinese mahogany (Liu et al. 4

FIG. 1. CHANGES IN AW OF SAUSAGE INCORPORATED WITH PLANT EXTRACTS AT 4C DURING STORAGE


K. ALIREZALU ET AL.


TABLE 2. CHANGES IN pH OF SAUSAGE INCORPORATED WITH PLANT EXTRACTS AT 4C DURING STORAGE Storage time (day) Treatment Control GTE SNE OLE

1

15 Aa

6.51 6 0.03 6.26 6 0.04Ca 6.33 6 0.06Ca 6.42 6 0.04Ba

30 Cb

6.02 6 0.02 6.18 6 0.05Bb 6.25 6 0.02Ba 6.37 6 0.03Aa

45 Bc

5.79 6 0.04 5.97 6 0.03Ab 6.01 6 0.03Ab 5.94 6 0.05Ab

5.24 6 0.02Dd 5.74 6 0.06Bd 5.98 6 0.04Ab 5.57 6 0.06Cc

a–d pH level within each row with different letters differ significantly (P < 0.05). A–D pH level within each column with different letters differ significantly (P < 0.05).

patties incorporated with natural constitutes decreased from 5.7 to 5.5 over the 12 days storage period but ellagic acid, sesamol, lutein and OLE had no influence on pH (P > 0.05) in relation to the control.

Lipid Oxidation (TBARS) Antioxidant activity of meat and meat products could be a useful index to predict oxidative stability (Sacchetti et al. 2008). There were significant differences (P < 0.05) on the antioxidant activity of Frankfurter type sausages by addition of GTE, SNE and OLE as natural antioxidants stored at 4C for 45 days. Lipid oxidation increased significantly (P < 0.05) in all sausages during storage; however, the rate of the increase in the control was higher than in the other samples (Table 3). GTE, SNE and OLE have antioxidant activity dependent on the level of addition (G€ ulçin et al. 2004) and especially plant extract type (Karabacak and Bozkurt 2008). GTE, SNE and OLE reduced (P < 0.05) lipid oxidation in comparison to the control by an average of 40, 20 and 26%, respectively. Alp and Aksu (2010) reported that treated ground beef with 500 ppm SNE and MAP showed the lowest TBARS values compared to other groups during storage. Qin et al. (2013) found that antioxidant mechanism of phenolic compounds is mainly due to their capacity in chelating metal ions and trapping reactive oxygen species, which could generate radicals. The samples involved GTE had lowest TBARS values comparing to the control and sausages with added OLE and SNE. The high content of phenolic compounds contained in

plant extracts may cause its strong antioxidant ability (Li et al. 2006). The same authors observed strong antioxidant effect of GTE in bologna type sausages (Jongberg et al. 2013), SNE in sucuk (Karabacak and Bozkurt 2008) and OLE in cooked pork sausages (Hayes et al. 2011). Also, Negi and Jayaprakasha (2003) reported that there is a significant relation between phenolic content and antioxidant activity of plant extract. Results revealed that OLE was successful in inhibiting rancidity deterioration of oils (Bouaziz et al. 2008) and it had the strong protective effect on cells against oxidative stress (Carpenter et al. 2006).

Phenolic Changes Phenolic content of sausages decreased significantly (P < 0.05) during storage (Fig. 2). Daskalaki et al. (2009) revealed that phenolic compounds can be reduced during heating and storage through oxidative reactions. The highest phenolic content was noticed in sausage incorporated with 500 ppm GTE compared to other tested samples (Fig. 2). Plant extracts are rich in phenolic compounds which are secondary plant metabolites in a wide range of specialized functions. The health and technological benefits associated with plant extract application in value added meat products have been attributed to the antioxidant capacity, free radical-scavenging and antimicrobial activity of phenolic compounds (Rusak et al. 2008). The previously published data showed that phenolic compounds play also a major role in preventing certain chronic human diseases. Specific health-promoting effects of plant phenolic compounds

TABLE 3. CHANGES IN TBARS VALUES OF SAUSAGE INCORPORATED WITH PLANT EXTRACTS AT 4C DURING STORAGE Storage time (day) Treatment

1

15

30

45

Control GTE SNE OLE

0.36 6 0.04Bd 0.25 6 0.04Cc 0.53 6 0.07Ad 0.34 6 0.07BCd

1.41 6 0.03Ac 1.19 6 0.06Bb 0.98 6 0.07Cc 0.71 6 0.07Dc

2.13 6 0.03Ab 1.25 6 0.04Cb 1.88 6 0.09Bb 1.36 6 0.06Cb

2.74 6 0.06Aa 1.78 6 0.08Da 2.26 6 0.07Ba 2.01 6 0.07Ca

a–d TBARS values level within each row with different letters differ significantly (P < 0.05). A–D TBARS values level within each column with different letters differ significantly (P < 0.05).


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cantly (P < 0.05) decreased by 17.95% in the control, 14.54% in sausage containing SNE, 12.37% in sausage containing OLE and 6.23% in sausage containing GTE during storage (Table 4).Treatment and storage had significant effect (P < 0.05) on a* value of the surface color. The addition of SNE and OLE had a negative effect on color stability as a* value decreased (P < 0.05) following addition of plant extract at 500 ppm to sausage compared to control. However, the addition of plant extract can also help improve the color stability of sausage samples during storage. Fernandez-L opez et al. (2004) and Fernandez-Gines et al. (2005) found greater relation between redness and lipid oxidation in meat products, reporting that lipid oxidation resulted in decreases redness. Sausages incorporated with GTE had high levels of a* value and phenolic compounds compared to the control and sausages with SNE and OLE. Hayes et al. (2010a) reported that OLE at concentrations of 100 and 200 ppm enhanced color stability (P < 0.05) from days 0 to 12 of aerobic storage by increasing a* value compared to the control. The significant decrease (P < 0.05) in a* value indicates the change in meat color due to the prooxidative activity which attributed to its ability to release iron from heme pigments (Kanner et al. 1991). Yellowness (b* value) decreased (P < 0.05) in all samples due to browning reactions during storage period which concur with Bozkurt (2006) and Zarringhalami et al. (2009). Samples incorporated with GTE had the highest b* value as compared to other treated sausages (Table 4).

FIG. 2. CHANGES IN PHENOLIC CONTENT OF SAUSAGE INCORPORATED WITH PLANT EXTRACTS AT 4C DURING STORAGE

include inhibition of the oxidation of low-density lipoproteins (Visioli and Galli 2002).

Color Measurement The color of the Frankfurter type sausages was affected by addition of the plant extracts. The L* value of control and value added sausages decreased significantly (P < 0.05) over 45 days of storage (Table 4). The sausages incorporated with high amount of plant extracts revealed more intense dark color and less pink color due to the browning reaction during 45 days of storage (Bozkurt 2006). Results showed that using low concentrations of SNE had no effect on L* value of sucuk a Turkish dry fermented sausage (Karabacak and Bozkurt 2008). Sausage with added a 500 ppm GTE had higher L* value than sausage with added SNE and OLE. This data concur with the previously published data (Kayaardi and Gok 2003; Hayes et al. 2011). Samples with added plant extracts followed a similar pattern on redness (a* value). In the other words, a* value signifi-

Microbiological Properties Total viable count increased significantly (P < 0.05) in sausage samples during storage period. Sausage incorporated with SNE had the lowest total viable count (Fig. 3a). On the other hand, SNE, GTE and OLE can be effect on total viable

TABLE 4. CHANGES IN L*, a*, b* VALUES OF SAUSAGE INCORPORATED WITH PLANT EXTRACTS AT 4C DURING STORAGE Storage time (day) Values L*

a*

b*

Treatment Control GTE SNE OLE Control GTE SNE OLE Control GTE SNE OLE

1

15 Aa

58.34 6 0.42 56.53 6 0.16Ba 54.86 6 0.27Ca 55.75 6 0.54BCa 14.37 6 0.13Aa 13.48 6 0.25Ba 13.75 6 0.38Ba 13.26 6 0.22Ba 17.38 6 0.23Ca 20.37 6 0.35Aa 18.72 6 0.34Ba 20.36 6 0.54Aa

30 Ab

57.74 6 0.63 56.24 6 0.22Ba 52.97 6 1.53Db 54.81 6 0.57Ca 13.28 6 0.22Ab 13.72 6 0.53Aa 13.16 6 0.43Aab 12.78 6 0.46Ab 16.64 6 0.30Cb 20.22 6 0.62Aa 17.96 6 0.37Bab 19.94 6 0.32Aa

45 Ab

57.35 6 0.37 54.79 6 0.26Bb 51.49 6 0.64Cc 52.48 6 0.86Cb 13.21 6 0.10Ab 12.96 6 0.17Aab 12.74 6 0.74ABb 12.01 6 0.35Bbc 16.97 6 0.46Cb 19.81 6 0.52Aab 18.37 6 0.74Ba 18.79 6 0.46ABb

55.22 6 0.86Ac 53.47 6 0.42Bc 51.37 6 0.67Cc 51.12 6 0.65Cc 11.79 6 0.36Bc 12.64 6 0.33Ab 11.75 6 0.31Bc 11.62 6 0.18Bc 16.32 6 0.65Cb 19.34 6 0.26Ab 17.48 6 0.31Bb 18.26 6 0.18Bc

a–c L*, a*, b* values level within each row with different letters differ significantly (P < 0.05). A–D L*, a*, b* values level within each column with different letters differ significantly (P < 0.05).

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K. ALIREZALU ET AL.


FIG. 3. CHANGES IN MICROBIOLOGICAL STATUS OF SAUSAGE INCORPORATED WITH PLANT EXTRACTS AT 4C DURING STORAGE (a) Total viable count and (b) mold and yeast count.

count and shelf life. This is in agreement with Aksu and Kaya (2004) who reported usage of stinging nettle in sucuk manufacturing affected Enterobacteriaceae, yeast and mold count of ground beef meat. Xi et al. (2012) found that green tea treatment at oyster/tea extract ratio of approximate 0.7 g/mL decreased Vibrio parahaemolyticus and total viable count in oysters during refrigerated storage. Several researchers have reported that GTE had a very strong antibacterial activity to inhibit growth of Staphylococcus aureus, Escherichia coli, Listeria monocytogenes, Proteus vulgaris, Pseudomonas fluorescens, Salmonella, Vibrio, Clostridium, Campylobacter and Bacillus (Diker et al. 1991; Chou et al. 1999; Sakanaka et al. 2000; Taguri et al. 2004; Mbata et al. 2008). Alp and Aksu (2010) found that MAP and 500 ppm SNE had significant effects on mesophilic, psychrotrophic, pseudomonas and lactic acid bacteria count in sucuk. The obtained results were paralleled to Siripatrawan and Noipha (2012) on pork sausage and Paiva-Martins et al. (2009) on pork meat. The addition of different plant extracts in Frankfurter type sausage led to decrease (P < 0.05) in mold and yeast count (Fig. 3b). However, results showed that there is a significant increase (P < 0.05) in mold and yeast count during storage period. It was also observed that the count of mold and yeast were the highest average in the control (2.78 log cfu/g) and sausage incorporated with OLE (2.57 log cfu/g) after 45 days of storage period. However, 500 ppm SNE and GTE treated samples was significantly (P < 0.05) lower as compared to other treated sausages (Fig. 3b). Coliform bacteria are commonly used bacterial indicators of hygienic quality of meat and meat products (Kunova et al. 2014). Coliforms were not detected probably due to primary meat quality and hygienic processing in any functional sausages and control. Similarly, Aksu and Kaya (2004) found that the SNE inhibited Enterobacteriacea in sucuk.

Texture Analysis Results showed that GTE, SNE and OLE increased Frankfurter type sausage hardness on day 30 of storage (Fig. 4). Sausage incorporated with OLE had the highest average texture properties during refrigerated storage. The addition of plant extracts have been reported to enhance maximum compression force (N) of deformation in emulsion type sausages which concur with data reported by Estevez et al. (2005). According to Mitsumoto et al. (1995), natural antioxidants maintain membrane integrity of muscle fibers by reducing lipids and proteins oxidation and decrease moisture loss which in turn would have an effect on the texture characteristics of sausage (Fig. 4). Hayes et al. (2011) found that lutein and ellagic acid reduced cooked pork sausages hardness during storage while there is no significant difference (P > 0.05) between sausage with added OLE and control sausage. Karel et al. (1975) indicate that oxidative reactions of proteins can be effective on protein solubility, result in cross links formation and aggregation which could

FIG. 4. MAXIMUM COMPRESSION FORCE OF SAUSAGE INCORPORATED WITH PLANT EXTRACTS AT 4C


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K. ALIREZALU ET AL.

try. Results of the present study demonstrated the effectiveness of GTE, SNE and OLE to inhibit microbial growth, lipid oxidation and improvement of texture, sensory attributes and shelf life extension of Frankfurter type sausage. Sausage with added GTE had the highest phenolic compounds (25.28 mg GA/100 g), antioxidant capacity and shelf life while sausage with added SNE had the highest microbiological quality (total viable and fungi count; 5.77 and 2.02 log cfu/g, respectively) and sensory scores (4.24 out of 5) and sausage with added OLE had the suitable texture (37.85N). Therefore, the use of mixed plant extracts can be suggested to improve Frankfurter type sausage quality and provide safer and functional meat products.

FIG. 5. CHANGES IN SENSORY SCORES OF SAUSAGES INCORPORATED WITH PLANT EXTRACTS AT 4C DURING STORAGE

REFERENCES describe the texture stability and increase in deformation compression force and hardness of the sausages.

Sensory Evaluation Sausage incorporating with SNE had the highest average flavor, freshness odor and overall acceptability at the end of storage. The texture scores in all sausage samples were acceptable and there were no significant difference (P < 0.05). The present study also showed no significant differences in color stability between sausage with added OLE and control sausage (Fig. 5). Otherwise, plant extracts delayed sausage spoilage and limiting the subsequent formation of off-flavors in the meat products (Hayes et al. 2010a,). It has been reported that sausage with added Borago officinalis extract and lycopene had no significant negative effect on sensory attributes of dry fermented sausages (GarcıaI~ niguez et al. 2009), as well as treatment of citrus water waste on the sensory characteristics of cooked sausage (ViudaMartos et al. 2009). These results were in agreement with literature that addition of ascorbate, GTE and grape seed extract to low sulfite beef patties also had no significant n effect on organoleptic properties during storage (Ba~ no et al. 2007). Organoleptic evaluation indicated that addition of plant extracts containing functional ingredients can be incorporated into Frankfurter type sausage without having a detrimental effect on the product sensory quality leading to an acceptable healthier meat product by providing bioactive components.

CONCLUSION Microbial contamination, lipid oxidation and shelf life stability are serious concerns for meat product manufacturers and consumers. Due to concerns regarding the toxicity of synthetic preservatives, plant extracts may prove useful as safe, natural and functional ingredients to the meat indus8

AKSU, M.I. 2003. T€ urk sucugu u €retiminde Urtica dioica L. €zerine etkisi. (ısırgan otu) kullanımının sucugun kalitesi u Turk. J. Vet. Anim. Sci. 27, 685–693. AKSU, M.I. and KAYA, M. 2004. Effect of usage Urtica dioica L. on microbial properties of sucuk a Turkish dry-fermented sausage. Food Control 15, 591–595. ALP, E. and AKSU, M.I. 2010. Effects of water extract of Urtica dioica L. and modified atmosphere packaging on the shelf life of ground beef. Meat Sci. 86, 468–473. AOAC. 1995. Meat and meat products. In Official Methods of Analysis, 16th ed. (P. Cunniff, ed.) pp. 1–23, Assoc. of Official Analytical Chemists International, Arlington, VA. ARIEF, I.I., SURYATI, T., AFIYAH, D.N. and WARDHANI, D.P. 2014. Physicochemical and organoleptic of beef sausages with teak leaf extract (Tectona grandis) addition as preservative and natural dye. Int. Food Res. J. 21, 2033–2042. BAKA, M., NORIEGA, E., TSAKALI, E. and VAN IMPE, J.F.M. 2015. Influence of composition and processing of Frankfurter sausages on the growth dynamics of Listeria monocytogenes under vacuum. Food Res. Int. 70, 94–100. S., DIAZ, P., RODRIGUEZ, M., GARRIDO, M.D. and ~ ON, BAN PRICE, A. 2007. Ascorbate, green tea and grape seed extracts increase the shelf life of low sulphite beef patties. Meat Sci. 77, 626–633. BIESALSKI, H.K. 2005. Meat as a component of a healthy diet – Are there any risks or benefits if meat is avoided in the diet? Meat Sci. 70, 509–524. BOUAZIZ, M., FKI, I., JEMAI, H., AYADI, M. and SAYADI, S. 2008. Effect of storage on refined and husk olive oils composition: Stabilization by addition of natural antioxidants from Chemlali olive leaves. Food Chem. 108, 253–262. BOZKURT, H. 2006. Utilization of natural antioxidants: Green tea extract and Thymbra spicata oil in Turkish dry-fermented sausage. Meat Sci. 73, 442–450. CARPENTER, R., O’CALLAGHAN, Y., O’GRADY, M., KERRY, J. and O’BRIEN, N. 2006. Modulatory effects of resveratrol, citroflavan-3-ol, and plant extracts derived extracts on oxidative stress in U937 cells. J. Med. Foods 9, 187–195.


K. ALIREZALU ET AL.

CHOI, S.H. and CHIN, K.B. 2003. Evaluation of sodium lactate as a replacement for conventional chemical preservatives in comminuted sausages inoculated with Listeria monocytogenes. Meat Sci. 65, 531–537. CHOU, C., LIN, L. and CHUNG, K. 1999. Antimicrobial activity of tea as affected by the degree of fermentation and manufacturing season. Int. J. Food Microbiol. 48, 125–130. COOPER, R., MORRE, D.J. and MORRE, D.M. 2005. Medicinal benefits of green tea: Part I. Review of noncancer health benefits. J. Altern. Complement. Med. 11, 521–528. DASKALAKI, D., KEFI, G., KOTSIOU, K. and TASIOULA-MARGARI, M. 2009. Evaluation of phenolic compounds degradation in virgin olive oil during storage and heating. J. Food Nutr. Res. 48, 31–41. € M. DIKER, K.S., AKAN, M., HASCELIK, G. and YURDAKOK, 1991. The bactericidal activity of tea against Campylobacter jejuni and Campylobacter coli. Lett. Appl. Microbiol. 12, 34–35. EBRAHIMZADEH, M.A., POURMORAD, F. and HAFEZI, S. 2008. Antioxidant activities of Iranian corn silk. Turk. J. Biol. 32, 43–49. ECONOMOU, T., POURNIS, N., NTZIMANI, A. and SAVVAIDIS, I.N. 2009. Nisin–EDTA treatments and modified atmosphere packaging to increase fresh chicken meat shelf-life. Food Chem. 114, 1470–1476. ESKANDARI, M.H., HOSSEINPOUR, S., MESBAHI, G.H. and SHEKARFOROUSH, S.H. 2013. New composite nitrite free and low-nitrite meat-curing systems using natural colorants. Food Sci. Nutr. 1, 392–401. ESTEVEZ, M., VENTANAS, S. and CAVA, R. 2005. Protein oxidation in frankfurters with increasing levels of added rosemary essential oil: Effect on colour and texture deterioration. J. Food Sci. 70, 427–432. EXARCHOU, V., FIAMEGOS, Y.C., VANBEEK, T.A., NANOS, C. and VERVOORT, J. 2006. Hypenated chromatographic techniques for the rapid screening and identification of antioxidants in methanolic extracts of pharmaceutically used plants. J. Chromatogr. A 1112, 293–302. FAUSTMAN, C., SPECHT, S.M., MALKUS, L.A. and KINSMAN, D.M. 1992. Pigment oxidation in ground veal: Influence of lipid oxidation, iron and zinc. Meat Sci. 31, 351–362. FDA. 2013. Bacteriological Analytical Manual for Foods. US Government Printing Office, Washington, D.C. FEINER, G. 2006. Meat Products Handbook, pp. 287–289, CRC Press, Inc., New York. J.M., FERNANDEZ-LOPEZ, J., FERNANDEZ-GIN ES, SAYAS-BARBERA, E. and PEREZ-ALVAREZ, J.A. 2005. Meat products as functional foods: A review. J. Food Sci. 70, 37–43. J.M., FERNANDEZ-L OPEZ, J., FERNANDEZ-GIN ES, ALESON-CARBONELL, L., SENDRA, E., SAYAS-BARBERA, J.A. 2004. Application of functional E. and PEREZ-ALVAREZ, citrus by products to meat products. Trends Food Sci. Technol. 15, 176–185.


~ GARCIA-INIGUEZ, D.E., CIRIANO, M., GARCIA-HERREROS, C., LAREQUI, E., VALENCIA, I., ANSORENA, D. and I. 2009. Use of natural antioxidants from ASTIASARAN, lyophilized water extracts of Borago officinalis in dry fermented sausages enriched in E-3 PUFA. Meat Sci. 83, 271–277. GEORGANTELIS, D., AMBROSIADIS, I., KATIKOU, P., BLEKAS, G. and GEORGAKIS, S.A. 2007. Effect of rosemary extract, chitosan and a-tocopherol on microbiological parameters and lipid oxidation of fresh pork sausages stored at 48C. Meat Sci. 76, 172–181. € OKTAY, M. and € ¸IN, I., _ KUFREVIO € GULC GLU, O., € € BUYUKOKUROGLU, M.E. 2004. Antioxidant, antimicrobial, antiulcer and analgesic activities of netle (Urtica dioica L.). J. Ethnopharmacol. 90, 205–215. HAYES, J.E., STEPANYAN, V., ALLEN, P., O’GRADY, M.N. and KERRY, J.P. 2010a. Effect of lutein, sesamol, ellagic acid and olive leaf extract on the quality and shelf-life stability of packaged raw minced beef patties. Meat Sci. 84, 613–620. HAYES, J.E., STEPANYAN, V., ALLEN, P., O’GRADY, M.N. and KERRY, J.P. 2010b. Evaluation of the effects of selected phytochemicals on quality indices and sensorial properties of raw and cooked pork stored in different packaging systems. Meat Sci. 85, 289–296. HAYES, J.E., STEPANYAN, V., ALLEN, P., O’GRADY, M.N. and KERRY, J.P. 2011. Evaluation of the effects of selected plant-derived nutraceuticals on the quality and shelf-life stability of raw and cooked pork sausages. LWT – Food Sci. Technol. 44, 164–172. IBRAHIM, H.M., MOAWAD, R.K. and EMAM, W.H. 2012. Antioxidant effect of pomegranate rind, seed extracts and pomegranate juice on lipid oxidation and some quality properties of cooked beef patties. J. Appl. Sci. Res. 8, 4023–4032. JONGBERG, S., TORNGREN, M.A., GUNVIG, A., SKIBSTED, L.H. and LUND, M.N. 2013. Effect of green tea or resemary extract on protein oxidation in bologna type sausages prepared from oxidatively stressed pork. Meat Sci. 93, 538–546. KANNER, J., HAREL, S. and JAFFE, R. 1991. Peroxidation of muscle food as affected by NaCl. J. Agric. Food Chem. 39, 1017–1021. KARABACAK, S. and BOZKURT, H. 2008. Effects of Urtica dioica and Hibiscus sabdariffa on the quality and safety of sucuk (Turkish dry-fermented sausage). Meat Sci. 78, 288–296. KAREL, M., SCHAICH, K. and ROY, R.B. 1975. Interaction of peroxidizing methyl linoleate with some proteins and amino acids. J. Agric. Food Chem. 23, 159–163. KAYAARDI, S. and GOK, V. 2003. Effect of replacing beef fat with olive oil on quality characteristics of Turkish soudjouk (sucuk). Meat Sci. 66, 249–257. KHAYYAL, M.T., EL-GHAZALY, M.A., ABDALLAH, D.M., NASSAR, N.N., OKPANYI, S.N. and KREUTER, M.H. 2002. Blood pressure lowering effect of an olive leaf extract (Oleo


9


K. ALIREZALU ET AL.

europaea) in L-NAME induced hypertension in rates. Arzneim.-Forsch. Drug Res. 52, 797–802. S., BOBKOVA, A., LOPASOVSKY, L. and KUNOVA, KACANIOVA, M. 2014. Microbiological evaluation of poultry sausages stored at different temperatures. Potravinarstvo 8, 141–145. LEON, K., MERY, D., PEDRESCHI, F. and LEON, J. 2006. Color measurement in L*a*b* units from RGB digital images. Food Res. Int. 39, 1084–1091. LI, Y., GUO, C., YANG, J., WEI, J., XU, J. and CHENG, S. 2006. Evaluation of antioxidant properties of pomegranate peel extract in comparison with pomegranate pulp extract. Food Chem. 96, 254–260. LIU, D.C.H., TSAU, R.T., LIN, Y.C.H., JAN, S.H.S.H. and TAN, F.J. 2009. Effect of various levels of rosemary or Chinese mahogany on the quality of fresh chicken sausage during refrigerated storage. Food Chem. 117, 106–113. MANGANELLI, R.E.U., ZACCARO, L. and TOMEI, P.E. 2005. Antiviral activity of Urtica dioica L., Parietaria diffusa M. and K. and Sambucus nigra L. J. Ethnopharmacol. 98, 323–327. MARTINEZ, L., DJENANE, D., CILLA, I., BELTRAN, J.A. and RONCALES, P. 2006. Effect of varying oxygen concentrations on the shelf-life of fresh pork sausages packaged in modified atmosphere. Food Chem. 94, 219–225. MBATA, T.I., DEBIAO, L.U. and SAIKIA, A. 2008. Antibacterial activity of the crude extract of Chinese green tea (Camellia sinensis) on Listeria monocytogenes. Afr. J. Biotechnol. 7, 1571–1573. MEDINA, E., DE CASTRO, A., ROMERO, C., RAMIREZ, E. and BRENES, M. 2013. Effect of antimicrobial compounds from olive products on microorganisms related to health, food and agriculture. In Microbial Pathogens and Strategies for Combating Them: Science, Technology and Education (A. Mendez-Vilas, ed.) pp. 1087–1094, Formatex Research Center, Badajoz. V., PEREZ, MICOL, V., CATURLA, N., PEREZ-FONS, L., MAS, L. and ESTEPA, A. 2005. The olive leaf extract exhibits antiviral activity against viral haemorrhagic septicaemia rhabdovirus (VHSV). Antivir. Res. 66, 129–136. MITSUMOTO, M., ARNOLD, R.N., SCHAEFER, D.M. and CASSENS, R.G. 1995. Dietary vitamin E supplementation shifted weight loss from drip to cooking loss in fresh beef longissimus during display. J. Anim. Sci. 73, 2289–2294. MITSUMOTO, M., O’GRADY, M.N., KERRY, J.P. and BUCKLEY, D.J. 2005. Addition of tea catechins and vitamin C on sensory evaluation, colour and lipid stability during chilled storage in cooked or raw beef and chicken patties. Meat Sci. 69, 773–779. NEGI, P.S. and JAYAPRAKASHA, G.K. 2003. Antioxidant and antibacterial activities of Punica granatum peel extracts. J. Food Sci. 68, 1473–1477. OMAR, S.H. 2010. Oleuropein in olive and its pharmacological effects. Sci. Pharm. 78, 133–154. PAIVA-MARTINS, F., BARBOSA, S., PINHEIRO, V. and MOURAO, J.L. 2009. The effect of olive leaves 10

supplementation on the feed digestibility, growth performances of pigs and quality of pork meat. Meat Sci. 82, 438–443. ~ PEREIRA, A.P., FERREIRA, I.C., MARCELINO, F., VALENTAO, P., ANDRADE, P.B., SEABRA, R. and PEREIRA, J.A. 2007. Phenolic compounds and antimicrobial activity of olive (Olea europaea L. Cv. Cobrançosa) leaves. Molecules 12, 1153–1162. QIN, Y.Y., YANGA, J.Y., LUA, H.B., WANGA, S.H.S.H., YANGA, J., YANGA, X.C.H., CHAIA, M., LIB, L. and CAO, J.X. 2013. Effect of chitosan film incorporated with tea polyphenol on quality and shelf life of pork meat patties. Int. J. Biol. Macromol. 61, 312–316. RUSAK, G., KOMES, D., LIKIC, S., HORZIC, D. and KOVAC, M. 2008. Phenolic content and antioxidative capacity of green and white tea extracts depending on extraction conditions and the solvent used. Food Chem. 110, 852–858. SACCHETTI, G., CARLA DI MATTIA, C., PAOLA PITTIA, P. and MARTINO, G. 2008. Application of a radical scavenging activity test to measure the total antioxidant activity of poultry meat. Meat Sci. 80, 1081–1085. SAKANAKA, S., JUNEJA, L.R. and TANIGUCHI, M. 2000. Antimicrobial effects of green tea polyphenols on thermophilic spore-forming bacteria. J. Biosci. Bioeng. 90, 81–85. SALLAMA, K.H.I., ISHIOROSHIB, M. and SAMEJIMA, K. 2004. Antioxidant and antimicrobial effects of garlic in chicken sausage. Lebensm.-Wiss. U.-Technol. 37, 849–855. SEBRANEK, G.J. and BACUS, J.N. 2007. Cured meat products without direct addition of nitrate or nitrite: What are the issues? Meat Sci. 77, 136–147. SEZIK, E., YES¸ILADA, E., HONDA, G., TAKAISHI, Y., TAKEDA, Y. and TANAKA, T. 2001. Traditional medicine in Turkey X. folk medicine in Central Anatolia. J. Ethnopharmacol. 75, 95–115. SIRIPATRAWAN, U. and NOIPHA, S. 2012. Active film from chitosan incorporating green tea extract for shelf life extension of pork sausages. Food Hydrocolloids 27, 102–108. STONE, H. and SIDEL, J.L. 2004. Sensory Evaluation Practices, pp. 201–245, Elsevier Academic Press, California. TAGURI, T., TANAKA, T. and KOUNO, I. 2004. Antimicrobial activity of 10 different plant polyphenols against bacteria causing food-borne disease. Biol. Pharm. Bull. 27, 1965–1969. TAKABAYASHI, F., HARADA, N., YAMADA, M., MUROHISA, B. and OGUNI, I. 2004. Inhibitory effect of green tea catechins in combination with sucralfate on Helicobacter pylori infection in Mongolian gerbils. J. Gastroenterol. 39, 61–63. TALHAOUI, N., TAAMALLI, A., GOMEZ-CARAVACA, A.M., FERNANDEZ-GUTIERREZ, A. and SEGURA-CARRETERO, A. 2015. Phenolic compounds in olive leaves: Analytical determination, biotic and abiotic influence, and health benefits. Food Res. Int. 77, 92–108. TANG, S., KERRY, J.P., SHEEHAN, D., BUCKLEY, D.J. and MORRISSEY, P.A. 2001. Antioxidative effect of added tea


K. ALIREZALU ET AL.

catechins on susceptibility of cooked red meat, poultry and fish patties to lipid oxidation. Food Res. Int. 34, 651–657. THIAGU, R., CHAND, N. and RAMANA, K.R. 1993. Evolution of mechanical characteristics of tomatoes of two varieties during ripening. J. Sci. Food Agric. 62, 175–183. TODA, M., OKUBO, S., HIYOSHI, R. and SHIMAMURA, T. 1989. Antibacterial and bactericidal activities of Japanese green tea. Jpn. J. Bacteriol. 44, 669–672. VISIOLI, C. and GALLI, C. 2002. Biological properties of olive oil phytochemicals. Crit. Rev. Food Sci. Nutr. 42, 209–221. VIUDA-MARTOS, M., RUIZ-NAVAJAS, Y., FERNANDEZ-L OPEZ, J. and PEREZALVAREZ, J.A. 2009. Effect of adding citrus waste water, thyme and oregano essential oil on the chemical, physical and sensory


characteristics of a bologna sausage. Innovative Food Sci. Emerg. Technol. 10, 655–660. XI, D., LIU, C. and SU, Y.C. 2012. Effects of green tea extract on reducing Vibrio parahaemolyticus and increasing shelf life of oyster meats. Food Control 25, 368–373. ZARRINGHALAMI, S., SAHARI, M.A. and HAMIDI-ESFEHANI, Z. 2009. Partial replacement of nitrite by annatto as a color additive in sausage. Meat Sci. 81, 281–284. ZHANG, W., XIAO, S.H., SAMARAWEERA, H., LEE, E.J. and AHN, D.U. 2010. Improving functional value of meat products. Meat Sci. 86, 15–31. ZHONG, R.Z., TAN, C.Y., HAN, X.F., TANG, S.X., TAN, Z.L. and ZENG, B. 2009. Effect of dietary tea catechins supplementation in goats on the quality of meat kept under refrigeration. Small Ruminant Res. 87, 122–125.


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