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with higher water holding capacity is more desired because it will result in a higher product yield.
The crude protein obtained for beef, chevon and pork in this study are slightly lower than 25%, 23% and 25% obtained by USDA (2001) for beef, chevon and pork respectively. The values obtained for crude protein and ash contents of beef in this study are higher than the range (18.86-19.15%) and (0.95-0.98%) obtained for crude protein and ash contents respectively by Akhter et al. (2009). However, the ether extract (1.86-1.98%) and moisture (76.28-77%) contents obtained by these same authors were higher than values obtained for beef in this study. Also, the ether extract value (1.17%) obtained for beef by Lapital et al.
(2004) was less than the value obtained in this study. The protein content of chevon obtained was higher than 19.47% and 19.89% while the moisture content was lower than 76.62% and 76.37% obtained for goat kids fed different diets by Adam et al. (2010). However, the values obtained for crude protein and ash for chevon in this study are higher than 19.48-20.86%;
1.00-1.08% for crude protein and ash reported respectively obtained by Silva et al. (2011) for goat fed different levels of licury oil in the diet. It was noticed that chevon had the highest ash content compared to either beef or pork and this agrees with the report of Casey (1992) that chevon meat are rich in potassium compared to either beef or pork.
The high nutritional properties obtained for chevon in this study corroborates the reports of Adam et al. (2010) that goat meat is higher in quality than sheep or cattle meat. Gadiyaram and Kannan (2004) also reported that chevon is a good source of red meat for the production of further-processed meat foods because of its superior water-holding capacity and nutritional properties. The protein content of (22.66%) obtained for pork in this study is higher than 20.15% obtained by Hodgson et al. (1991). However, the moisture and ether extract contents were lower than those reported by the same author while the ash content was higher than 1.00% (Moss et al., 1983). The variation noticed in the chemical compositions of the meat types could be influenced by different factors such as species, breed, age, anatomical location of muscle and nutrition (Lawrie, 1998).
There were noticeable increases in the nutrient profiles of the products. For instance, the percentage increase in the nutrient profile were 74%, 120%, 84% for crude protein,18%,94%, 135% for ash contents, 72%, 34%, 17% for ether extracts for beef floss, chevon floss and pork
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floss respectively. These indicate that meat floss is a nutrient dense product. The crude protein, ash and ether extract contents of the products were probably a reflection of what was in their corresponding raw meat with the raw meat with highest crude protein producing highest crude protein after processing. The result obtained for the products in this study also agrees with the report of Addrizo (1999) that roasted chevon had lower calories, fat, and saturated fat, but higher protein and iron than roasted beef, pork and lamb. Significant differences existed among the crude protein of the products and this follows the report of Gadiyaram and Kannan (2004) when beef, chevon and pork were used to make sausages and similar protein contents were observed in their products. The fat contents of meat floss in this study followed the trend observed in the sausages made with these three types of meat.
Gadiyaram and Kannan (2004) reported that the fat content of chevon sausage was lower than beef or pork sausages, similar trend was observed in this study. This might be due to the fact that pork initially had a higher fat content than beef and during the process of frying a substance with initial high fat absorbed less fat from the frying medium and vice versa as reported by Fillion and Henry (1998).
The decrease in the moisture content and increase in the total fat content of the products agreed with the results of Badiani et al. (2002) and Kesava et al. (1996) who found that losses in the moisture content resulted in higher dry matter and increased content of total lipid and other components in cooked meat samples.
The moisture content of a product is one of the criteria that determine the extent of microbial spoilage of that product, because water is one of the constituents that aid bacteria growth. The more water a product contains, the more conducive the environment will be for microbial activity. The moisture contents (17.69-19.59%) of the different meat floss obtained in this study is above the range values of 8.60-13.56% obtained for different serunding (shredded meat) produced in Malaysia as reported by Huda et al. (2012). It is also higher than 2.8-10.3%
obtained by Abubakar et al. (2011) for processed meats from non-ruminants which include danbu (shredded meat) and also lower than the values obtained by Ogunsola and Omojola (2008) for Danbunama. However, the protein content values obtained are higher than the range of 38.92-41.21% reported by Ogunsola and Omojola (2008) and higher than the values of 34.09-42.90% obtained for pork floss by Ockerman and Li (1999). The fat contents of the
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products obtained in this study falls within the range of 3.20-31.14% obtained by Huda et al.
(2012) for different shredded meat. The wide variation of fat contents reported in their research was attributed to the level ofoil added to the product or the application of processes by the producer to remove excessive oil during serunding (meat floss) preparation.
Nevertheless, the slight differences obtained in this study could be attributed to the initial fat content of the raw meats.
The yield from chevon during meat floss production was the highest compared to either beef or pork. This might be due to the fact that chevon had the highest water holding capacity in its raw state and water holding capacity and yield are directly proportional. That is, a meat with high water holding capacity is expected to have a high yield because it implies that the meat releases less of its water, resulting in less cooking loss during application of external forces such as cooking.
The most important contributing sensory attributes to eating quality are tenderness, flavour and juiciness (Safari et al., 2001). Tenderness is defined as the ease of mastication, which involves initial penetration by the teeth, the breakdown of meat into fragments and the amount of residue remaining after chewing (Lawrie, 1998). It is an integrated textural property composed of mechanical, particulate and chemical components. The mechanical characteristics include hardness, cohesiveness, elasticity, grittiness and fibrousness while the chemical characteristics of meat include juiciness and oiliness (Brewer and Novakofski, 2008). Tenderness has also been shown to depend positively upon intramuscular fat (Aaslyng and Støier, 2004). Juiciness is an important factor in sensory evaluation as it facilitates the chewing process as well as brings the flavour component in contact with the taste buds (Aaslyng et al., 2002). It depends on the raw meat quality and the cooking procedure (Aaslyng et al., 2002). Juiciness is the feeling of moisture in the mouth during chewing. It is a dynamic attribute changing during the chewing process (Aaslyng, 2002) and positively correlated to intramuscular fat (Cummings et al., 1999; Brewer et al., 2001). The two sensory descriptive words for juiciness, in cooked meat, are initial and sustained juiciness (Lyon and Lyon, 1989). Initial juiciness is the amount of fluid released by the cut surface of meat, during compression between the forefinger and thumb (AMSA, 1995) and is positively correlated with the water holding capacity of meat (Offer and Trinick, 1983). Sustained juiciness is
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described as the perceived juiciness after a few seconds of mastication, due to the presence of intramuscular fat stimulating saliva secretion (Lawrie, 1998).
Flavour is experienced during mastication when volatiles are released in the oral cavity. It is mainly generated during the heating process and the Maillard reactions involving reducing carbohydrates and amino acids are one of the most important routes to flavour formation (Mottram, 1991).
It would have been expected that the flavour and tenderness of beef floss should be preferred to meat floss from chevon because chevon is considered to be lower in palatability than beef, pork, or lamb (Griffin et al., 1992), but from the results obtained meat floss from chevon and pork were preferred by the panelists. The preferred flavour of chevon floss could be as a result of the large volume of oil absorbed compared to beef floss because the oil is rich in polyunsaturated fatty acid.
The aroma of the products were scored low (all values were below average) probably due to the presence of garlic that has a characteristic pungent odour due to the presence of vanilloids, especially 6-gingerol (Ippoushi et al., 2003). The tenderness of chevon could be attributed to the presence of zingibain in ginger (which acts as a tenderizer) which might have acted on the chevon muscle to tenderize it. It would have been expected that the juiciness of beef floss would be more preferable than chevon floss because juiciness of meat is reported to be a function of intramuscular fat content (Eikelenboom et al., 1996) but the reverse was observed in this study. However, it was noticed that pork floss had higher aroma than meat floss from beef and chevon. The low aroma score for chevon meat floss agrees with the report of Casey (1992) that goat meat has a less desirable flavour, aroma tenderness and juiciness. The preference of the panelists for either pork or chevon floss could be attributed to the fact that most people are familiar with beef so they will always want to explore new products which might affect their judgment. However, despite their preferences for chevon and pork floss in most attributes of the eating qualities, beef floss was well accepted to the panelists than either chevon or pork floss which implies that people still prefer beef to any other meat.
It would have been expected that the products should be free of microorganisms when it was freshly produced because of the high temperature the products were subjected to, but analysis showed that the freshly prepared products still contained some microorganisms. The microbes
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might have contaminated the product either through the environment of the processing industry, the utensils used or the personnel as reported by Cabeza et al. (2009).
Generally, it was noticed that as the days of storage increased, the microbial load of the products increased until at a point when they started to decrease. The increase in the microbial load could be related to the growth phase of the bacteria. During this phase, it is assumed the microbes have adjusted to their environment and there is available nutrient for them to actively grow in number by regular cell division. The later decrease in microbial load of the products as storage days increased could be attributed to the death phase of the microbes.
During this phase, the rate at which the microbes die exceeds their growth rate causing a reduction in the numbers of viable cells. It is assumed that the microbes have depleted all the available nutrients that aid their growth which explains why there was reduction in the microbial load of the product at the 21st day of storage.
The high microbial load found in chevon could be attributed to its high nutrient profile (crude protein and ash content) coupled with its high moisture contents and as compared to other meat floss. Also, it is the product with initial high number of microbes. These are agents that aid the proliferation of microbes and determined the microbial load that will be found in such product at the end of storage time. An aberration to this trend was noticed in the case of pork floss and beef floss. Pork floss had a higher nutrient profile than beef floss, but the microbial load of pork floss in any of the packaging media during storage was lower than beef floss. An exception to this was noticed on the 7th day of storage where the microbial load of pork floss was higher than that of beef floss. The reason for this is not known.
It has been reported that lipid oxidation and microbial growth in meat products can be controlled or minimized by using either synthetic or natural food additives (Lee et al., 1997;
Mielnik, et al., 2003). Also, Istrati et al. (2011) reported that some spices and herbs are valued for their antimicrobial activities and medicinal effects in addition to their flavor and fragrance qualities. Furthermore, many studies had reported that phenolic compounds in spices and herbs significantly contribute to their antioxidant and pharmaceutical properties (Shan, et al., 2005; Wu et al., 2006). Some studies claimed that the phenolic compounds present in spices and herbs might also play a major role in their antimicrobial effects (Hara-Kudo et al., 2004).
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The decrease in the microbial load and the slow rate of lipid oxidation of the products during storage could be attributed to the presence of antimicrobial/bacterial and antioxidant properties contained in some of the spices used. For instance, onions and garlic contain allicin which have anti microbial and antioxidant properties (Dorman and Deans, 2000; Benkeblia, 2004 quoted in Istrati et al., 2011). However, the microbial load obtained in the meat products in this study does not exceed log107 cfu/g/cm2 at which microbial spoilage is detected in meat products as reported by Korkeala (1987) quoted in Kalalou (2010)
The thiobarbituric acid reactive substances (TBARS) values have been commonly considered as an index of lipid rancidity. The quantitative production of malonaldehyde during oxidation of fat in stored food is responsible for TBARS values. The level of malondialdehyde generated in meat/ stored meat products can be determined using the TBARS assay (Jo and Ahn, 1998).
The TBARS value in this study increased as the day of storage increased in all the packaging materials and this agrees with the report of Alam et al. (2005) that during storage the TBARS value increases due to the decomposition of the oxidized lipids. The study revealed that meat floss made from chevon had the highest TBARS, which implies that rate of lipid oxidation in chevon floss is higher than either beef or pork floss, This might be due to the fact that oil absorption was highest in chevon floss during preparation (oil is rich in polyunsaturated fatty acids). Also, despite its low lipid content compared to meat from other ruminants, chevon has a high proportion of unsaturated fatty acids in addition to being a source of conjugated linoleic acid (Webb et al., 2005). Xiao et al. (2011) reported that several intrinsic and extrinsic factors, including the content and composition of unsaturated fatty acids and the concentration and activity of antioxidant substances in meat muscle can affect its oxidative stability.
Mielnik et al. (2006) asserted that meat with high polyunsaturated and a high degree of linoleic fatty acids have accelerated oxidative processes. This support the report of Ahn et al.
(1998) that the baseline lipid oxidation status of raw meat was a very important determinant of the progression of lipid oxidation in cooked meat.
The high TBARS value of chevon meat floss indicates that chevon floss has a shorter shelf life than beef or pork floss. This corroborates the report of Eega et al. (2005) and Lee et al.
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(2005) that the shelf life of chevon products may be shorter than beef products due to higher lipid oxidation rate.
It would have been expected that pork, due to its high fat content, will deteriorate faster or have a higher oxidative rate than beef, but the result showed that pork floss had a low TBARS values in all the packaging media. This might be attributed to the fact that the unsaturated fatty acid found in pork is rich in monounsaturated fatty acid as compared to fats in other ruminants (Vandendriessche, 2008). The monounsaturated fats contain less sites for oxidation, which implies that the rate of lipid oxidation in pork floss will be low compared to other meat floss. Furthermore, pork possesses high saturated fat that is stable and less reactive. In contrary, the fats found in beef are located intramuscular and cannot be trimmed off and, being high in unsaturated fat, are susceptible to oxidation. Furthermore, the phospholipid found in beef is higher than that of pork. Reports had shown that phospholipids are considered to be responsible for about 90% of lipid oxidation (Pikul et al., 1984; Buckley et al., 1989).
During storage of the products it was observed that the TBARS value increased as the number of days increased in all the products and in all the packaging media. This corroborates the report of Singh et al. (2011) that oxidation increases as the period of storage increases.
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Yield and quality attributes of meat floss as influenced by muscles types