الفهرس 
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Abstract
The aim of this investigation is to utilize mushroom (Agaricus.spp) in some popular meat products such as burge Physical, chemical and sensory properties of suggested products were followed throughout frozen storage at -18ºC / 3 months to choice the best treatment (best substitution ratio of mushroom) according to the collected dataThe obtained results could be summarized as follows: 5.1. Proximate composition:5.1.1. Beef burger (Champio-burger):At zero time of storage, sample treated with 10% mushroom (B1) had higher moisture content (67.70%), while the other two treatments (20 and 30% mushroom) had moisture content with 60%. After 45 days of frozen storage, a similar trend was also noticed with minimized percentages; i.e. 63.90, 61.10 and 62.40% for 10,20 and 30% mushroom, respectively. After 90 days of storage, a decremental trend was recorded in different treatments.Minimizing beef meat by different levels (10,20 and 30%) did not affect the total protein content; i.e. use of mushroom as fortifier maintains the protein content in such product either at zero time or throughout 90 days of frozen storage. At zero time, no detectable effect on fat % was noticed owing to mushroom used in making burger process. Similar trend was recorded after 45 days of frozen storage with higher ratios (12 – 25%). At the end of storage (after 90 days), all treatments had a fat content ranged between 23 – 26% higher than corresponding content of control sample.Ash content in various treatments was about 0.03% as a maximum detected level in different treatments at zero time and during whole storage period.5.1.2. Beef sausage (Champio-sausage): Moisture content in treated samples ranged between 65 – 69.50% lower than that of control one (71.50%). During frozen storage, moisture content was contentiously decreased to be 56.59% after 45 days of storage reached to 41 – 47.60% after 90 days of storage. Similar trend that found in burger treatments in case of protein content was also recorded in sausage protein content. It was about 15.50% in different samples and slightly changed during storage period.At zero time, the three suggested treatments possessed fat content lower than that of control one. It was about 16% in S1 and S2 treatments; meanwhile, it was sharply decreased to be 11% in S3 treatment, due to higher percent of mushroom (30%) used in this treatment. During frozen storage, fat content raised to be around 25% in different samples.Similar finding that found in case of beef burger was also recorded in sausage samples with ash content. 5.2. Physical properties:5.2.1. pH value:- At zero time, pH value was increased to be 6.85 to 6.91 than that of control one (6.75). At the end of storage period (90 days), pH value was continuously increased to be around 7.3 in different investigated samples.- Regarding to sausage samples, similar trend was also recorded during whole storage period (90 days).5.2.2. Water holding capacity and plasticity:- At zero time, B2 treatment had a higher water holding capacity followed by B1 and B3 treatments. After 45 days of storage, a noticeable decrease was recorded in water holding capacity. The higher water holding capacity was recorded in B1 treatment followed by B2 and B3 treatments. A continuous decreasing in water holding capacity was recorded at the end of storage period (90 days).- No difference was noticed in plasticity of burger samples at zero time. It ranged between 3.5 to 4 cm2 in different samples; i.e. addition of mushroom did not affect the plasticity of investigated samples. After 45 days of storage, there was no change in plasticity, while after 90 days the plasticity of different treatments was increased to be 6 – 8 cm2 in treated samples. - S1 treatment had higher water holding capacity, while the other two treatments had lower water holding capacity rather than that of control one. A decremented trend was recorded throughout frozen storage period in various treatments.- At zero time, there was no effect on plasticity owing to use of different ratios of mushroom. An incremental trend in plasticity was recorded in both of control and S1 samples till the end of storage period, while for S2 and S3 treatments such incremental trend was detected till 45 days of storage.5.3. Chemical properties:5.3.1. TBA value:- The effect of mushroom in minimizing lipid oxidation could be seen especially in B1 treatment at zero time. Similar trend was recorded during frozen storage period that extended to 90 days at -18ºC.- Regarding to sausage samples, S2 treatment had a lower TBA value rather than other two treatments, so, B1 treatment (burger fortified with 10% mushroom) as well as S2 treatment (sausage fortified with 20% mushroom) are the best suggested treatments (mushroom added percent).5.3.2. Effect of mushroom addition on hardness of beef burger and sausage:- Addition of 20and 30% of mushroom to the batter of beef burger resulted in increase in hardness of cooked samples upon cooking (zero time), while at 90 days of frozen storage, these beef burger samples become less hard (higher penetration values), may be due to softening of encysted mushroom tissue.- On contrary, cooked sausage samples showed softness (higher penetration values) immediately after cooking (zero time) and become very hard at the end of 90 days frozen storage (lower penetration values).5.4. Cooking measurements:5.4.1. Cooking loss and cooking yield:- At zero time, cooking loss % of different burger samples did not significantly affected. It was 49.88% in control sample, while it was 49.64, 48.85 and 48.61% in B1, B2 and B3, respectively. This result indicates that the higher the mushroom level, the lower the percentage of cooking loss. At the end of frozen storage period, all of these percentages were minimized showing B3 treatment as the best treatment which coincided with the results of sensory evaluation.- Regarding the cooking yield %, a reversible trend was normally recorded, i.e. the higher the mushroom level, the higher the cooking yield % at zero time of frozen storage. from these data it could be concluded that B3 treatment (30% mushroom) is the most favorite treatment.- Similar findings that detected earlier were also noticed in case of cooking loss and cooking yield percentages but the best treatment in case of sausage was S2 treatment (20% mushroom).5.4.2. Diameter, thickness and shrinkage:- Reduction % in burger diameter was affected either by added mushroom percent or frozen storage period. At zero time, various treatments showed lower reduction percent rather than that of control one with about 1-2%. Similar trend was noticed throughout frozen storage period (90days) with about 2-5% rather than that of control one.- Concerning thickness increment (%) of different cooked burger, B1 treatment did not differ from control sample at zero time (37.78%), while other two treatments (B2 and B3) had lower incremental percentage with 5 and 7%, respectively lower than that of control and B1 treatments.- After 45 days of frozen storage, such percentage was raised with about 4% in both of control and B3 treatments, while the corresponding percentages in B1 and B2 were 1 and 1.6%, respectively. Such result assured that B3 treatment is the favorite treatment in case of burger which goes in parallel with mean scores of sensory evaluation.- At the end of frozen storage period (90 days), the aforementioned percentage was minimized as a general trend in all investigated treatments to be 30-31%.- Shrinkage percent of various investigated burger indicated that B3 treatment showed a lower shrinkage % compared with control and other two treatments.- After 45 days of frozen storage period, shrinkage percent was consequently increased with similar trend that recorded at zero time. Meanwhile, at the end of storage period (90 days), such percent was minimized in all of investigated samples with similar trend that detected at zero time.- The highest thickness incremental percent was recorded in S2 treatment (20% mushroom) at zero time showed it as a favorite treatment that agreed with sensory evaluation. At the end of frozen storage similar trend was also recorded.- Regarding shrinkage percentage of sausage treatments, such percent in treated samples was lower than that of control at zero time of storage. At the end of storage period, similar trend was recorded showing S2 treatment as the best treatment (lower shrinkage %) that agreed with sensory evaluation.5.5. Colour characteristics of burger and sausage samples:- Lightness (L-values), redness (a-values) and yellowness (b-values) of uncooked beef burger recorded higher values than those of cooked burger.- Both hue and chroma values of cooked burger were lower than their corresponding values of uncooked burger.- The addition of different levels of mushroom in the batter of beef burger did not greatly influence the lightness values of fresh and cooked burger at zero time of storage.- However, the addition of 20% mushroom (B2) has maintained the original L-values of beef burger, may be due to the antioxidative effect of the added mushroom. However, redness (a-values) and yellowness (b-values) of beef burger were reduced during 90-days of frozen storage for uncooked beef burger, while the yellowness values (b-values) of cooked samples were increased. The increase in yellowness (b-values) of cooked beef burger during frozen storage led correspondingly to increase hue and chroma values after 90 days of frozen storage. Lightness (L-values) of uncooked sausage were decreased by the addition of mushroom, specially at 30% level, while changes in the redness (a-values) and yellowness (b-values) were not greatly affected by the addition of mushroom. However, hue values were decreased, while chroma values were increased, especially at 20% level of addition. During the period of frozen storage, the lightness and yellowness values of sausage samples with 30% addition were higher at the end of storage period, by comparing with their L-value at zero time, which indicates the protective effect of mushroom on colour parameters of raw sausages.Hue values of raw sausage fortified with 30% mushroom were lower than those of control or samples fortified with 10 or 20% mushroom. Frozen storage led to a decrease in hue values of raw sausage except sample fortified with 30% mushroom. Chroma values were decreased during frozen storage in all raw sausage samples except that fortified with 30% mushroom, where the chroma value was relatively stable. Cooking of sausage samples led to a dramatic decrease in lightness (L-values) of the outer surface of the treated sausage, except that fortified with 30% mushroom. On the other side, the redness (a-values) of the outer side were slightly higher than those of the interior side of treated sausage samples, while the yellowness (b-values) of outer side of sausage samples were dramatically reduced during cooking in comparison to their values of inside surface. The hue values were lower for the outside surface compared with the corresponding values of the interior surface. Addition of mushroom enhanced colour parameters (L, a, b, hue and chroma) of sausage samples either for outside or inside surfaces.However, frozen storage of cooked sausage samples for 90 days led to reduction in colour parameters of outer side and inside surface of treated samples, where greenish colour shade (negative a-values) were occured after 90 days of frozen storage.Similar change was observed for hue values of inside and outside surface during frozen storage. On contrary, chroma values of frozen sausage were increased at the end of storage, especially for those samples fortified with 20 and 30% of mushroom.5.6. Amino acids content:The essential amino acids of favorite treatment either from burger or sausage was identified. The same content was found in burger sample (B3) compared with its control one, while sausage treatment (S2) had a slight increase in essential amino acids rather than that of its control one.- Regarding to the non-essential amino acids content of sausage sample fortified with different levels of mushroom, data showed similar content in investigated sample compared with its control one (60%). Meanwhile, the investigated burger samples showed lower non-essential amino acids content (54.63%) than that of control one (60.18%).5.7. Sensory evaluation of cooked burger and sausage:- (B3) burger treatment (30% mushroom) had higher scores in all investigated sensory attributes (appearance, colour, interior colour, texture, size, taste, odour, degree of cooking, juiciness, tenderness and overall acceptability).(S2) sausage treatment (20% mushroom) had higher scores in all investigated sensory attributes (appearance, colour, interior colour, texture, size, taste, odour, degree of cooking, juiciness, tenderness and overall acceptability). Data indicated that sensory scores were significantly decreased as the time of frozen storage increased in all burger or sausage samples.