**3. Incorporation of olive oil in meat products**

To develop healthier meat products, various technological options of replacing animal fat have been studied (Jiménez-Colmenero, 2007). Olive oil has been incorporated in meat emulsion systems such as frankfurters in liquid (Lurueña-Martinez et al., 2004; López-López et al., 2009a, 2009b) or interesterified form (Vural et al., 2004). However, oil-in-water emulsion is the most suitable technological option for stabilizing the non-meat fats added to meat derivatives as ingredients due to physicochemical properties (Bishop et al., 1993; Djordjevic et al., 2004). There are a number of procedures that can be used to produce a plant or marine oil-in-water emulsions (with an emulsifier, typically a protein of non-meat origin) for meat products (Jiménez-Colmenero, 2007), but only sodium caseinate has been used to stabilize olive oil for incorporation in frankfurter-type products (Paneras & Bloukas, 1994; Ambrosiadis et al., 1996; Paneras et al., 1998; Pappa et al., 2000; Choi et al., 2009).


Tables 1 and 2 are examples of fmomulas that use olive oil and different fat replacers in producing an emulsion-type sausage and pork patty.

1) Isolated soy protein: carrageenan: maltodextrin: water = 2:1:1:20.

2) ICM+Olive Oil.

3) NaCl: NaNO2 = 99:1.

Table 1. Formulation of emulsion-type low-fat sausages manufactured with and without fat replacers.

Meat Products Manufactured with Olive Oil 425

ICMO. Therefore, the replacement of animal fat with olive oil may produce products with healthier lipid composition (higher MUFAs, mainly oleic acid) without substantial

In pork patty study, moisture content was significantly higher in the products with olive oil+ISP+carageenan (T2) and T2 with maltodextrin (T3) when compared with control and that with olive oil+ISP (T1) (Table 4). In contrast, control and T1 had significantly higher crude protein than T2 and T3. Crude fat content was higher in T1 and T2. The pork patty with olive oil treatment had higher ash content than control. Pietrasik and Duda (2000) reported that the increased weight losses when the reduction of fat is accompanied by an increase in the proportion of moisture, and protein levels remain essentially the same. However, substitution of backfat with olive oil produced pork patty not only with higher in moisture but also higher fat content than control in this study. Thus, it can be assumed that olive oil substitution for backfat may not induce weight loss of pork patty. These results agreed with Pappa et al. (2000) who reported no significant difference in yield when olive

Treatment Fat (%) Protein (%) Moisture (%)

1 day 19.72±1.56a 15.06±0.71d 61.96±1.78d 15 days 19.36±1.34a 15.16±0.49d 61.34±1.40d 30 days 19.62±1.44a 15.34±0.70d 61.15±1.46d

1 day 3.34±0.63e 18.38±0.96a 74.58±1.15a 15 days 3.21±0.59e 18.23±0.84a 74.24±1.06a 30 days 4.63±0.46d 17.79±0.52ab 72.77±0.58b

1 day 7.35±0.19c 16.70±0.75bc 73.24±0.75ab 15 days 8.65±0.29b 17.27±0.50ab 71.08±0.95c 30 days 8.58±0.42b 16.60±0.49bc 71.12±1.06c

 C T1 T2 T3 Moisture 60.42±0.65B2) 60.32±1.05B 62.15±0.22A 61.63±0.37AB Crude Protein 23.37±0.44A 20.28±0.62BC 19.54±0.76C 21.30±1.84B Crude fat 14.93±0.90B 17.34±0.41A 16.29±1.05A 14.88±0.85B Ash 1.28±0.02B 2.06±0.13A 2.02±0.03A 2.19±0.11A

a-e Means ± S.E. with different letters in the same column indicate significant differences (*p*<0.05). Table 3. Chemical composition of emulsion-type low-fat sausages with or without fat

2) A-C Means ± SD with different superscripts in the same row significantly differ at p<0.05.

Table 4. Proximate compositions in pork patty made by substituted olive oil for backfat

deterioration in nutritional quality.

oil was replacing pork fat in low-fat frankfurters.

Control

ICM1)

ICM O1)

1) See Table 1.

replacers

1)See Table 2.


1)C, 10 % backfat; T1, 5 % backfat + 5% olive oil + 0.5 % isolated soy protein; T2, 5% backfat + 5% olive oil + 0.5% isolated soy protein + 0.5% carageenan (T2). T3, 5% backfat + 5% olive oil + 0.5% isolated soy protein + 0.5% carageenan + 0.5% martodextrin.

Table 2. Formulation of pork patty with fat replacers

#### **3.1 Chemical composition and nutritional value of meat products manufactured with olive oil**

The chemical composition of emulsion-type sausages indicated that fat content was reduced by replacing the pork backfat with ICM, but increased with added olive oil (Table 3). Replacing backfat with fat replacers resulted in increased fat content at day 30 for ICM and day 15 and 30 for ICMO; however, the control was not differ. These results could be due to increased moisture loss (%) with longer storage time. ICM and ICMO had higher moisture content than control. When pork backfat is fully replaced by oil-in-water emulsion, which contains 52% olive oil, the sausage contains approximately 13 g of olive oil per 100 g of product. This means a considerable increase in the proportion of MUFA. Olive oil can make up almost 70% of the total fat content of the sausage. The caloric content of sausages was 225-245 kcal/100 g, and 70% of which were from fat. In traditional sausages, all are supplied by animal fat, whereas, in the sausage replaced with olive oil, the animal fat supplied only 20%. The other 50% is from the olive oil. It was suggested that meat products, strategically or naturally enriched with healthier fatty acids, can be used to achieve desired biochemical effects without dietary supplements or changing dietary habits (Jiménez-Colmenero et al., 2010).

Up to 7 – 13 g of olive oil could be added per 100 g sausages as an animal fat replacer. However, the purpose of replacing animal fat with olive oil is to produce low-fat products, and consequently such high proportion of olive oil is not desirable (Jiménez-Colmenero et al., 2007). One of the fundamental strategies in developing a healthier lipid formula is concentrating active components in target food products to enable the cosumption of recommended intake levels with normal portion sizes. Dietary models provided by the World Health Organization (2003) suggested that MUFA should be the major dietary fatty acids. If MUFAs are the predominant fatty acids in a product, the total fat intake would not be substantial (Pérez-Jiménez et al., 2007).

Protein content of the sausage (ICMO) containing ICM and olive oil was higher than that of the control. This could be attributed to higher lean content and ISP in the formulation of

Lean pork 83.5 81.0 80.5 80.0 Pork back fat 10.0 5.0 5.0 5.0 Olive oil - 5.0 5.0 5.0 ISP - 0.5 0.5 0.5 Carageenan - - 0.5 0.5 Maltodextrin - - - 0.5 Salt 1.2 1.2 1.2 1.2 Black pepper 0.3 0.3 0.3 0.3 Water 5.0 7.0 7.0 7.0 Total 100 100 100 100 1)C, 10 % backfat; T1, 5 % backfat + 5% olive oil + 0.5 % isolated soy protein; T2, 5% backfat + 5% olive oil + 0.5% isolated soy protein + 0.5% carageenan (T2). T3, 5% backfat + 5% olive oil + 0.5% isolated soy

**3.1 Chemical composition and nutritional value of meat products manufactured with** 

The chemical composition of emulsion-type sausages indicated that fat content was reduced by replacing the pork backfat with ICM, but increased with added olive oil (Table 3). Replacing backfat with fat replacers resulted in increased fat content at day 30 for ICM and day 15 and 30 for ICMO; however, the control was not differ. These results could be due to increased moisture loss (%) with longer storage time. ICM and ICMO had higher moisture content than control. When pork backfat is fully replaced by oil-in-water emulsion, which contains 52% olive oil, the sausage contains approximately 13 g of olive oil per 100 g of product. This means a considerable increase in the proportion of MUFA. Olive oil can make up almost 70% of the total fat content of the sausage. The caloric content of sausages was 225-245 kcal/100 g, and 70% of which were from fat. In traditional sausages, all are supplied by animal fat, whereas, in the sausage replaced with olive oil, the animal fat supplied only 20%. The other 50% is from the olive oil. It was suggested that meat products, strategically or naturally enriched with healthier fatty acids, can be used to achieve desired biochemical effects without dietary supplements or changing dietary habits (Jiménez-Colmenero et al.,

Up to 7 – 13 g of olive oil could be added per 100 g sausages as an animal fat replacer. However, the purpose of replacing animal fat with olive oil is to produce low-fat products, and consequently such high proportion of olive oil is not desirable (Jiménez-Colmenero et al., 2007). One of the fundamental strategies in developing a healthier lipid formula is concentrating active components in target food products to enable the cosumption of recommended intake levels with normal portion sizes. Dietary models provided by the World Health Organization (2003) suggested that MUFA should be the major dietary fatty acids. If MUFAs are the predominant fatty acids in a product, the total fat intake would not

Protein content of the sausage (ICMO) containing ICM and olive oil was higher than that of the control. This could be attributed to higher lean content and ISP in the formulation of

protein + 0.5% carageenan + 0.5% martodextrin.

be substantial (Pérez-Jiménez et al., 2007).

**olive oil** 

2010).

Table 2. Formulation of pork patty with fat replacers

C T 1 T 2 T 3

ICMO. Therefore, the replacement of animal fat with olive oil may produce products with healthier lipid composition (higher MUFAs, mainly oleic acid) without substantial deterioration in nutritional quality.

In pork patty study, moisture content was significantly higher in the products with olive oil+ISP+carageenan (T2) and T2 with maltodextrin (T3) when compared with control and that with olive oil+ISP (T1) (Table 4). In contrast, control and T1 had significantly higher crude protein than T2 and T3. Crude fat content was higher in T1 and T2. The pork patty with olive oil treatment had higher ash content than control. Pietrasik and Duda (2000) reported that the increased weight losses when the reduction of fat is accompanied by an increase in the proportion of moisture, and protein levels remain essentially the same. However, substitution of backfat with olive oil produced pork patty not only with higher in moisture but also higher fat content than control in this study. Thus, it can be assumed that olive oil substitution for backfat may not induce weight loss of pork patty. These results agreed with Pappa et al. (2000) who reported no significant difference in yield when olive oil was replacing pork fat in low-fat frankfurters.


1) See Table 1.

a-e Means ± S.E. with different letters in the same column indicate significant differences (*p*<0.05).

Table 3. Chemical composition of emulsion-type low-fat sausages with or without fat replacers


1)See Table 2.

2) A-C Means ± SD with different superscripts in the same row significantly differ at p<0.05.

Table 4. Proximate compositions in pork patty made by substituted olive oil for backfat

Meat Products Manufactured with Olive Oil 427

were found among the samples with 50% olive oil substitution for backfat. Fat retention was higher in the olive oil-substuted samples than control. Especially T3, the patty with olive oil+ISP+carageenan, showed the highest fat retention. However, cooking loss was not different among the treatments. In this present study, WHC was steadily decreased as olive oil substitution level increased. However, this does not mean that the quality of pork patty decreased, because fat retention was higher in olive oil-added pork patties, and cooking loss

In other meat product studies, Kayaardi and Gok (2003) reported that replacing beef fat with olive oil had no effect on the pH value of the Soudjouks samples. Luruena-Martinez et al. (2004) and Muguerza et al. (2002) reported that the addition of olive oil did not produce significant differences in cooking losses of sausage but made the sausage lighter in color and more yellow (Muguerza et al., 2002). In contrast, Bloukas et al. (1997) reported that the higher the olive oil content, the higher the weight loss, probably due to higher amounts of water added. Hur et al. (2008) repoprted that WHC was decreased but fat retention was

Color of meat products is an important quality parameter for purchase decision by consumers. The most common cause for changing color is the formation of metmyoglobin by oxygen-dependent meat enzymes. Aerobic micro-organisms are successfully competing with meat pigments for oxygen. Formation of metmyoglobin can vary, and occasionally discolored areas are present adjacent to and fully demarcated areas where coloration is bright pink. Use of low-quality fat containing high levels of peroxides can cause oxidation of

Varnam & Sutherland(1995) reported that sausages can have a number of specific quality issues: 'Pressure marks' are the result of oxygen deficiency where packed sausages are in close contact to each other. Pigment is initially converted to reduced myoglobin and subsequently, as some diffusion of oxygen occurs, to metmyoglobin. 'White spot' appears to be an oxidative defect, which involves formation of circular grey or white areas that increase in size with continuing storage. It could be associated with low SO2 levels and use of fats

The sausage incorporated with ICM and olive oil as fat replacers showed higher yellowness and redness (Table 7). Yellower color could be from the original color of olive oil and redder color from higher lean ratio, which includes higher myoglobin content, compared to

Olive oil and ISP are known to have antioxidant properties. The sausages emulsified with ISP and olive oil (ICMO) inhibited lipid oxidation (Table 7). The progress of lipid oxidation can cause changes of meat quality including color, flavor, odor, texture and even the nutritional value in meat products (Fernandez et al., 1997). The stability of fat often limits the shelf life of meat products. The incorporation of olive oil and ISP into meat products may improve the shelf life of the products due to their antioxidant properties. In our study, TBARS values of ICMO were lower than those of the control on days 15 and 30. The TBARS of ICMO sample remained constant throughout the 30 days of storagebut those of the control and ICM increased (*p*< 0.05) from days 15 to 30. The higher TBARS value for the

control on each storage day might be due to high fat content in control sausages.

**3.3 Color and lipid oxidation of meat products manufactured with olive oil** 

was not significantly different.

increased by olive oil substitution.

with a high peroxide content.

traditional sausages (control).

meat pigments (Varnam & Sutherland, 1995).

#### **3.2 Physicochemical properties of meat products manufactured with olive oil**

The water holding capacity (WHC) of meat products provide succulent texture and mouthfeel to consumers. A number of studies have proved that there are an inverse relationship between fat content and the amount of water released (Hughes et al., 1997). In Table 5, ICMO was not difference in WHC when compared with the control. It means that olive oil can be combined with other fat replacers such as ISP and carrageenan to improve WHC in meat products. In the case of ICMO, which was emulsified with ISP and carrageenan, the release of water seemed to be protected during storage days.

Cooking loss of meat products is usually influenced by fat content. The products with higher fat content lose less water after cooking ((Jiménez-Colmenero et al., 2007) because high-fat products contain less water. The cook losses of the low-fat sausages manufactured with olive oil and fat replacers (ICM and ICMO) were lower than those of the control (Table 5). However, when the reduction of fat contents in the sausages was considered, the increase of cook loss is not significant. Some fat replacers such as whey protein, carrageenan and tapioca starch could reduce the cook loss of low-fat sausages due to water retainability (Lyons et al., 1999).


1) See Table 1., a-d Means ± S.E. with different letters in the same column indicate significant differences (*p*<0.05).

Table 5. Water holding capacity (WHC, %) and cook loss (%) of low-fat sausages with or without fat replacers


1) See Table 2., 2) A-C Means ± SD with different superscripts in the same row significantly differ at p<0.05.

Table 6. Changes of physical characteristics in pork patty made by substituted olive oil for backfat

On other hand, WHC of pork patty was significantly higher in control and T3 than T1 and T2. Control had higher pH than olive oil-added pork patties, but no significant differences

The water holding capacity (WHC) of meat products provide succulent texture and mouthfeel to consumers. A number of studies have proved that there are an inverse relationship between fat content and the amount of water released (Hughes et al., 1997). In Table 5, ICMO was not difference in WHC when compared with the control. It means that olive oil can be combined with other fat replacers such as ISP and carrageenan to improve WHC in meat products. In the case of ICMO, which was emulsified with ISP and

Cooking loss of meat products is usually influenced by fat content. The products with higher fat content lose less water after cooking ((Jiménez-Colmenero et al., 2007) because high-fat products contain less water. The cook losses of the low-fat sausages manufactured with olive oil and fat replacers (ICM and ICMO) were lower than those of the control (Table 5). However, when the reduction of fat contents in the sausages was considered, the increase of cook loss is not significant. Some fat replacers such as whey protein, carrageenan and tapioca starch could

Treatment WHC (%) Cook loss (%)

1 day 71.02±1.17a 13.30±0.37cd 15 days 69.52±0.89ab 13.18±0.53d 30 days 68.33±0.93b 13.86±0.52bcd

1 day 68.32±0.59b 14.37±0.82bc 15 days 67.95±0.95bc 14.78±0.48a 30 days 66.77±0.59c 14.90±0.40a

1 day 69.79±0.43ab 13.13±0.54d 15 days 69.12±1.18ab 14.01±0.34bc 30 days 68.28±0.82b 14.61±0.52ab

1) See Table 1., a-d Means ± S.E. with different letters in the same column indicate significant differences

Table 5. Water holding capacity (WHC, %) and cook loss (%) of low-fat sausages with or

 C T1 T2 T3 pH 5.82±0.03A 5.75±0.02B 5.78±0.01B 5.78±0.02B WHC **(%)** 79.05±2.22A2) 72.05±1.12B 80.39±14.58B 83.99±12.65A Fat retention (%) 79.31±0.02C 83.97±0.01 B 84.64±1.06 B 86.61±1.28 A Cooking loss (%) 28.05±0.70 27.30±0.69 27.72±1.10 26.95±1.61 1) See Table 2., 2) A-C Means ± SD with different superscripts in the same row significantly differ at p<0.05. Table 6. Changes of physical characteristics in pork patty made by substituted olive oil for

On other hand, WHC of pork patty was significantly higher in control and T3 than T1 and T2. Control had higher pH than olive oil-added pork patties, but no significant differences

**3.2 Physicochemical properties of meat products manufactured with olive oil** 

carrageenan, the release of water seemed to be protected during storage days.

reduce the cook loss of low-fat sausages due to water retainability (Lyons et al., 1999).

Control

ICM1)

ICMO1)

(*p*<0.05).

backfat

without fat replacers

were found among the samples with 50% olive oil substitution for backfat. Fat retention was higher in the olive oil-substuted samples than control. Especially T3, the patty with olive oil+ISP+carageenan, showed the highest fat retention. However, cooking loss was not different among the treatments. In this present study, WHC was steadily decreased as olive oil substitution level increased. However, this does not mean that the quality of pork patty decreased, because fat retention was higher in olive oil-added pork patties, and cooking loss was not significantly different.

In other meat product studies, Kayaardi and Gok (2003) reported that replacing beef fat with olive oil had no effect on the pH value of the Soudjouks samples. Luruena-Martinez et al. (2004) and Muguerza et al. (2002) reported that the addition of olive oil did not produce significant differences in cooking losses of sausage but made the sausage lighter in color and more yellow (Muguerza et al., 2002). In contrast, Bloukas et al. (1997) reported that the higher the olive oil content, the higher the weight loss, probably due to higher amounts of water added. Hur et al. (2008) repoprted that WHC was decreased but fat retention was increased by olive oil substitution.

### **3.3 Color and lipid oxidation of meat products manufactured with olive oil**

Color of meat products is an important quality parameter for purchase decision by consumers. The most common cause for changing color is the formation of metmyoglobin by oxygen-dependent meat enzymes. Aerobic micro-organisms are successfully competing with meat pigments for oxygen. Formation of metmyoglobin can vary, and occasionally discolored areas are present adjacent to and fully demarcated areas where coloration is bright pink. Use of low-quality fat containing high levels of peroxides can cause oxidation of meat pigments (Varnam & Sutherland, 1995).

Varnam & Sutherland(1995) reported that sausages can have a number of specific quality issues: 'Pressure marks' are the result of oxygen deficiency where packed sausages are in close contact to each other. Pigment is initially converted to reduced myoglobin and subsequently, as some diffusion of oxygen occurs, to metmyoglobin. 'White spot' appears to be an oxidative defect, which involves formation of circular grey or white areas that increase in size with continuing storage. It could be associated with low SO2 levels and use of fats with a high peroxide content.

The sausage incorporated with ICM and olive oil as fat replacers showed higher yellowness and redness (Table 7). Yellower color could be from the original color of olive oil and redder color from higher lean ratio, which includes higher myoglobin content, compared to traditional sausages (control).

Olive oil and ISP are known to have antioxidant properties. The sausages emulsified with ISP and olive oil (ICMO) inhibited lipid oxidation (Table 7). The progress of lipid oxidation can cause changes of meat quality including color, flavor, odor, texture and even the nutritional value in meat products (Fernandez et al., 1997). The stability of fat often limits the shelf life of meat products. The incorporation of olive oil and ISP into meat products may improve the shelf life of the products due to their antioxidant properties. In our study, TBARS values of ICMO were lower than those of the control on days 15 and 30. The TBARS of ICMO sample remained constant throughout the 30 days of storagebut those of the control and ICM increased (*p*< 0.05) from days 15 to 30. The higher TBARS value for the control on each storage day might be due to high fat content in control sausages.

Meat Products Manufactured with Olive Oil 429

Chin et al. (1999) and Claus et al. (1990) found that redness and lightness values were more affected by fat/lean ratio and myoglobin concentration of the lean part. Muguerzaet al. (2002) and Bloukas et al. (1997) also found that replacing, in part, backfat with olive oil produced yellower sausages than controls. Muguerza et al. (2002) reported that antioxidant present in olive oil and ISP helped maintaining color by minimizing color oxidation. The present study is in agreement with the findings of other researchers (Kayaardi & Gök, 2003; Ansorena & Astiasarán, 2004; Bloukas et al., 1997) who reported increase of lipid oxidation in meat products during fermentation and ripening period. They found that replacing animal fat with olive oil was effective for inhibiting the lipid oxidation during storage. Our previous and present results indicated that replacing animal fat with olive oil can be

effective in inhibiting lipid oxidation in meat products during storage.

springiness and cohesiveness (Jiménez-Colmenero et al. 2010) (Table 9).

oil reduced juiciness scores.

1) See Table 1.

**3.4 Texture and sensory properties of meat products manufactured with olive oil** 

Textural properties of the emulsion-type sausages are affected by the replacement of backfat with olive oil emulsion (Table 9). In general, frankfurters made with oil-in-water emulsions presented higher hardness, cohesiveness and chewiness and lower adhesiveness than traditional frankfurters. The textural properties of frankfurters manufactured with olive oil are influenced by the characteristics of oil-in-water emulsion and its role in the meat protein matrix. Frankfurters with olive oil emulsion containing caseinate or soy protein presented similar hardness and chewiness to control, but those with soy protein presents higher

The frankfurters containing olive oil emulsion with caseinate or soy protein had higher hardness, cohesiveness, gumminess and chewiness values than the traditional sausages. The result of texture might be due to the reduced fat content sausages. In high fat frankfurters, in which pork backfat is replaced by olive oil, generally have less flavor intensity and are harder and less juicy (Jiménez-Colmenero et al., 2010). However, these differences are marginal, and the frankfurters received similar scores for general appearance and acceptability (Jiménez-Colmenero et al., 2010). Partial substitution of animal fat with olive

Parameter Control ICM1) ICMO1) Hardness (kg) 0.33±0.04b 0.42±0.02a 0.40±0.03a Cohesiveness 60.85±1.52b 66.47±0.90a 66.09±0.54a Springiness 13.11±0.27 13.53±0.04 13.23±0.24 Gumminess (g) 19.26±0.88b 22.09±0.65a 21.74±0.30a Chewiness (g) 228.70±6.02b 271.28±6.30a 268.11±8.55a

a-b Means ± S.E. with different letters in the same row indicate significant differences (*p*<0.05).¶(9pt)

Table 9. Textural attributes of low-fat sausages with or without fat replacers


1) See Table 1., a-e Means ± S.E. with different letters in the same column indicate significant differences (*p*<0.05).

Table 7. Color and lipid oxidation of low-fat sausages with or without fat replacers

L\*-value of raw pork patty was higher in control and T1 than other samples, but no significant difference were found after cooking (Table 8). a\*-value was significantly higher in control than the samples with olive oil-added products in both raw and cooked states. It can be assumed that redness may be higher in control than olive oil-added pork patties, but lightness and yellowness may not be much different. Paneras et al. (1998) also reported differences in color when low fat frankfurters were produced with different levels of vegetable oils. Low-fat frankfurters were darker, redder and more yellow than high fat frankfurters. However, Marquez et al. (1989) found no differences in color parameters by oil treatments in beef frankfurters. These studies indicated that the change of meat color by oil treatment can vary depending upon the meat products.


1) See Table 2.,

2) A-C Means ± SD with different superscripts in the same row significantly differ at p<0.05.

Table 8. Changes of meat color in pork patty by substituting backfat with olive oil

Yellownes s (*b\**)

TBARS (mg malonaldehyde/kg sample)

(*a\**)

1 day 78.39±0.37a 11.06±0.21b 3.45±0.17b 0.16±0.03c 15 day 77.25±0.64ab 10.41±0.19b 2.34±0.24c 0.22±0.03b 30 day 76.41±0.88b 10.22±0.09b 2.49±0.61bc 0.32±0.05a

1 day 74.95±0.69c 12.13±0.40a 3.30±0.16b 0.16±0.02c 15 day 73.48±0.98cde 10.42±0.07b 2.42±0.24bc 0.14±0.04cd 30 day 71.69±1.31e 10.29±0.13b 2.20±0.05c 0.24±0.02b

1 day 73.45±0.18de 11.80±0.64ab 4.04±0.13a 0.17±0.02c 15 day 72.49±0.17e 10.46±0.25b 2.44±0.15bc 0.15±0.04cd 30 day 72.01±0.65e 10.31±0.06b 2.79±0.13bc 0.20±0.03bc 1) See Table 1., a-e Means ± S.E. with different letters in the same column indicate significant differences

Table 7. Color and lipid oxidation of low-fat sausages with or without fat replacers

treatment can vary depending upon the meat products.

L\*-value of raw pork patty was higher in control and T1 than other samples, but no significant difference were found after cooking (Table 8). a\*-value was significantly higher in control than the samples with olive oil-added products in both raw and cooked states. It can be assumed that redness may be higher in control than olive oil-added pork patties, but lightness and yellowness may not be much different. Paneras et al. (1998) also reported differences in color when low fat frankfurters were produced with different levels of vegetable oils. Low-fat frankfurters were darker, redder and more yellow than high fat frankfurters. However, Marquez et al. (1989) found no differences in color parameters by oil treatments in beef frankfurters. These studies indicated that the change of meat color by oil

Color C T1 T2 T3

2) A-C Means ± SD with different superscripts in the same row significantly differ at p<0.05. Table 8. Changes of meat color in pork patty by substituting backfat with olive oil

L\* 55.89±1.46A2) 55.31±0.96A 52.00±0.62B 52.58±1.32B a\* 13.86±0.35A 11.75±0.63B 11.75±0.45B 11.84±0.52B b\* 9.46±0.09 9.77±0.48 9.04±0.70 9.48±0.49

L\* 62.11±5.90 63.98±3.58 66.71±0.40 66.26±1.94 a\* 7.60±0.30A 7.02±0.33B 6.67±0.13BC 6.07±0.24C b\* 9.37±0.73B 11.06±0.08A 8.57±0.56C 9.80±0.93AB

Treatment Lightness (*L\**) Redness

Control

ICM1)

ICMO1)

(*p*<0.05).

Raw sample

Cooked sample

1) See Table 2.,

Chin et al. (1999) and Claus et al. (1990) found that redness and lightness values were more affected by fat/lean ratio and myoglobin concentration of the lean part. Muguerzaet al. (2002) and Bloukas et al. (1997) also found that replacing, in part, backfat with olive oil produced yellower sausages than controls. Muguerza et al. (2002) reported that antioxidant present in olive oil and ISP helped maintaining color by minimizing color oxidation. The present study is in agreement with the findings of other researchers (Kayaardi & Gök, 2003; Ansorena & Astiasarán, 2004; Bloukas et al., 1997) who reported increase of lipid oxidation in meat products during fermentation and ripening period. They found that replacing animal fat with olive oil was effective for inhibiting the lipid oxidation during storage. Our previous and present results indicated that replacing animal fat with olive oil can be effective in inhibiting lipid oxidation in meat products during storage.
