Basic Informations

C.V

Name : Nasser Sayed
Address: El-Fayoum - Egypt.

Master Title

Sanitary Status of Fishes in Beni-Suef City

Master Abstract

During the present study 20 samples of pastirma (each of 250g weight) were collected from different shops at Beni-Suef city, the organoleptic criteria of the examined samples were as follows, regarding the colour of the coat, 25% of samples had fresh yellow colour while brown, dark brown and blackish brown were detected in 25%, 45% and 5% of the examined samples respectively. Considering the condition of coat, intact, craked and detached coat were detected in 45%, 45% and 40% of the examined samples respectively. In relation to the colour of meat surface 55% of samples possessed normal cure colour while fading and overcure were detected in 10% and 35% of the samples respectively. Regarding the condition of meat 60% of samples were found to be firm, the rest 40% of soft texture which may be due to under pressing or microbial spoilage. Looking to the knife stabs 55% of the examined samples was found to be closed while opened and mouldy knife stabs were detected in 40% and 20%of the examined samples respectively. Considering the odour of the coat normal specific odour of the coat (garlic and fenugreek) was detected in 75%of samples while sour and musty odour were detected in 20%and 5%of examined samples respectively and could be attributed to either the use of decayed garlic ot the overnight storage of previously prepared coat mixture. A normal cure odour of meat was detected in 70% of the samples while the rest of samples suffered from sour odour. Regarding the technological properties of retail pastirma, 65% of the examined samples showed fine coat particles while coarse coat particles were detected in 35% of the examined samples. On the other hand good and bad adhesive coat were detected in 55% and 45% of the examined samples. The thickness of coat was regularly and irregularly applied in 45% and 55% of the examined samples respectively. Regular dryness were found in 30%of examined samples while 30% and 40% of the examined samples suffered from inner soft and all soft defects respectively. Regarding the quality of pastirma meat 55%, 70% and 55% of the examined samples illustrated good technical properties from the aspects of pressing knife stabs and trimming. Moreover, only 55% of the slices of cured meat had normal cured pink colouration while overcure colour and fading were detected in 35%and 10%of the examined samples respectively. Even dryness of slices was detected in 50% of the examined samples. On the other hand 55% of the examined samples showed well binding properties of meat slices. Chemical analysis The mean value of pH of pastirma coat and meat were 5.38 ± 0.11and 5.32 ± 0.07 respectively. On the other hand the mean value of thiobarbturic acid (mg/kg) and total volatile nitrogen mg/100g of pastirma core were 0.37±0.067 and 21.94±1.24. It is worth to mention that none of the examined samples exceeded the permissible limit s in relation to total volatile nitrogen. The main values of moisture %, fat%, protein %, ash %, NaCl% and sodium nitrite residue content (ppm) were 52.615 ± 0.985, 7.38 ± 0.48, 29.79 ± 0.96, 9.12 ± 0.29, 7.65 ± 0.33 and 133.905 ± 11.05 respectively on wet weight basis. It is worth to mention that 5 samples (25%), 3 samples (15%), 10 samples (50%) and 7 samples (35%) comply with the E.S.S. (1991) in relation to moisture, fat, sodium chloride and sodium nitrite residue content. The differences in protein content among samples may be attributed to the higher fat content of some samples and the selection of high quality cuts by some factories which were further subjected to trimining and denuding. The high ash content of some samples could be attributed to high salt content. Microbiological investigation: The mean aerobic bacterial count, aerobic spore former count, anaerobic bacterial count, Staph. aureus count, Bacillus cereus count, coliform (MPN), Feacal coliform count (MPN), proteolytic microorganisms count, lipolytic microorganism count, total mould and yeast count per gram of pastirma coat were; 5x107± 107 , 106± 3x105, 106± 4x105 , 3x104± 104, 2x105± 6x104 ,140± 40, 59 ± 20, 3x 106± 106, 107± 3x106 and 2x105± 6x104 per gram respectively. While in pastirma meat these counts were; 2x107± 6x106, 4x105± 105, 107± 4x106, 2x105± 6x104, 5x104± 104 ,54± 15, 30 ± 9, 2x 107± 5x106, 4x107± 107 and 2x105± 5x104 per gram respectively. It is worth to mention that 15% of the examined pastirma meat sample comply with the E.S.S. (1991) in relation to anaerobic bacterial count i.e.these samples had anaerobic bacterial count below 102. On the other hand 20% and 25% of the examined pastirma meat samples had staph. aureus and mould and yeast counts which comply with E.S.S. (1991). Laboratory made pastirma with different nitrite levels: Pastirma was produced under laboratory conditions according to traditional method of production using three different nitrite treatments (200 ppm, 100ppm and 75ppm). The produced pastirma was kept at room temperature for twenty- one days and examined organoleptically, chemically and microbiologically after one week, two weeks and 3 weeks. The organoleptic examinations revealed that the colour of coat was fresh yellow in all the three treatments in the first week, then became brown in the second and third week in all the three treatments. The coat was still intact in all the three treatments along the examination period, while there was slight decrement in the percentage of coat to the total weight during the period of storage. Considering the colour of the meat surface, normal cure colour was detected in all treatments along the three weeks storage. Regarding the condition of meat surface firm texture and soft one were detected in 66.7% and 33.3% respectively in the 200ppm nitrite treatments, along the three weeks storage. In the 100ppm and 75ppm nitrite treatment the condition of meat surface were firm in all samples along the storage period. The knife stabs were closed in all treatments along the examination period. Normal specific odour of coat (fungreek and garlic) and meat were detected in all treatments along the examination period. Considering the technical properties of laboratory made pastirma fine coat particles, good adhesive coat and regular coat dryness were detected in all the examined samples in the three treatments along the storage period. On the other hand, regular coat thickness was detected in all samples of 100 ppm and 75 ppm nitrite treatments along the three weeks storage period. In the 200 ppm nitrite treatment regular and irregular coat thickness were detected in 66.7% (25 samples) and 33.3% (one sample) of the examined samples along the storage period. Regarding the technical properties of meat surface well and under pressed meat surface were detected in 66.7 % and 33.3% along the storage period in the 200ppm nitrite treatment. In the other two treatments the meat surface were well pressed in all the examined samples along the storage period. All the examined samples in the three treatments illustrates good technical properties from the aspects of knife stabs and trimming upon slicing of meat, all the examined samples in all treatments were normally cured (manifested by pink colouration of meat surface) along the storage period. Moreover dryness and well binding of meat slices were detected in all the examined samples along the three weeks storage period. Chemical analysis The mean value of the pH of both coat and meat decreased in the second week, then it began to rise again in the third week in all the three treatments. The mean values of total volatile nitrogen base mg/100g were significantly increased (p=0.05) during the storage period. The mean value of thiobarbturic acid number was significantly increased (p=0.05) from the first to the second week, but there was no significant difference between the second and third week in all the three nitrite treatments. Regarding the mean values of moisture content, there was significant decrease (p=0.05) in the moisture content in all the three treatments during the storage period. The decrement in the main value of fat in the three treatments was not significantly differed during the storage period. The mean value of ash were significantly different (p=0.05) between the first and third week in the 200 ppm nitrite treatment while in the other two treatments there were no significant variation. Regarding to the sodium nitrite residue content, there was significantly decrease (P=0.05) in its level during the storage period in the three treatments. Significantly variation in the salt content could be detected only in third week (significantly high, P=0.05) in the 100 ppm nitrite treatment. Microbiological investigation There was no significant variation between Aerobic plant count, anaerobic bacterial count, Lipolytic microorganisms count and total mould and yeast count in the three treatments along the three weeks storage period. Significant variation was found in Staph. aureus count in the first week (at which the treatment containing 75 ppm nitrite was significantly at P< 0.05 higher than the other two treatments ). There was significant variation in proteolytic microorganisms count, in which treatments with 75 ppm sod nitrite was significantly higher than 200 ppm and 100 ppm (P< 0.05) at the first and third weeks. In the second week the treatments with 200ppm was significant lower (P<0.05) than 100 ppm and 75 ppm nitrite treatments. 18.5%, 11.1% and 44.4% of the examined samples agree with the E.S.S. (1991) in relation to Staph. aureus count, Anaerobic bacterial count and mould and yeast count.

PHD Title

Studies For improving the quality of locally manufactured sausage

PHD Abstract

Part I. Survey on Quality of Retail Sausage: - Sixty samples (30 butcher and 30 frozen sausage) were collected from different supermarkets at Beni-suef province and butcher’s shops in Cairo, the samples were transferred to the laboratory for the following investigations: 1- Organoleptic and Sensory Examination: White, bright red, dark red and gray colours were detected in 50%,26%, 10% and 13.3% of examined butcher sausage, while these values were 0%, 66.7%, 20% and 13.3% in examined frozen sausage samples. Considering comminution, coarse and greasy comminution were detected in 13.3%, 86.7%, 90% and 10% of examined butcher and frozen sausage respectively. Regarding stuffing, 13.3% and 86.7% of butcher’s sausage were regular firm and irregularly smeared, respectively. While these values were 90% and 10% in frozen sausage, respectively. On the other hand, moderate, well, soft and flat forming were detected in 10%, 6.7%, 30% and 53.3% of butcher sausage, while they were 26.7%, 40%, 20% and 13.3 and 0% in frozen sausage respectively. On cooking the product, specific fleshy, spicy, low fleshy, rancid and putrid flavour were detected in 50%, 13.3%, 20%, 3.3% and 13.3% in butcher’s sausage, while they were 0%, 53%, 33.3% and 13.3% in frozen sausage respectively. Regarding, cooking loss 20% 63.3% and 16.7% of butcher sausage had cooking loss of 15%, 20% and 25%, while these values were 53.3%, 33.3% and 13.4% for frozen sausage respectively. The acceptability percentage of examined butcher sausage in relation to colour, comminution, stuffing, forming, odour and taste and cooking loss were 36.7%, 13.3, 13.3, 16.7, 63.3% and 20%, while these values in frozen sausage were 86.7%, 90%, 90%, 66.7%, 86.7% and 53.3%, respectively. 2- Chemical Quality Attributes: The mean values of pH, TBA value mg/kg and TVB-N mg / 100g of examined butchers sausage were 5.73 + 0.072, 0.19 + 0.027 and 28.96+ 1.12 respectively. While these values were 5.6 + 0.037, 0.15 + 0.012 and 22.88 + 0.90 for frozen sausage; respectively. It is worth to mention that, all the examined butcher and frozen sausage samples, comply width the E.S.S. No. 1972 / 1991 in relation to TBA value. On the other hand two samples (6.7%) and 10 samples (33.3%) of both butcher and frozen sausage comply with the E.S.S. No 1972 / 1991. 3- Chemical Analysis: The mean value of moisture %, fat %, protein %, ash %, NaCl % and Nitrite ppm in butcher sausage were 46.6 + 1.4, 35.86 + 0.74, 12.25 + 0.85, 2.06 + 0.05, 2.11 + 0.05 and 73.24 + 7.7, while they were 57.41 + 0.38, 26.75 + 0.55, 12.1 + 0.66, 2.08 + 2.17 + 0.05 and 83.29 + 5.53 in frozen sausage respectively. 4- Microbiological Analysis: The total bacterial count, Psychrotrophic count, Staph. aureus count, coliform (MPN), fecal coliform (MPN), Mould and yeast count / g of butcher sausage were 1.7 x109 + 4.4 x 107, 9.2 x 107 + 1.8 x 107, 1.8 x 105 + 3.7 x 104, 7.2 x 104 + 4.8 x 103, 3.4 x 104 + 6.2 x 103 and 7.5 x 104 + 2.1 x 104, respectively. These counts were 2.5 x 107 + 1.1 x 107, 1.2 x 107 + 7.3 x 106, 9.5 x 104 + 6.2 x 103, 7.5 x 103 + 2.2 x 103, 103 + 1.98 x 102 and 1.3 x 104 + 6 x 103 for frozen sausage, respectively. Bacillus cereus, Yersinia entrocolitica and E. coli could be isolated from 20%, 36.7% and 50% of examined butcher sausage samples, and from 33.3%, 20%, and 30% of examined frozen sausage samples; respectively. Part II – Improvement of Quality of Sausage: - 1- Effect of Potassium Chloride: Organoleptic Examination: - Substitution of sodium chloride by 30% and 40% of pot. chloride did not affect organoleptic and sensory properties of sausage during frozen or refrigeration storage. Control, 30% and 40% potassium chloride treated samples were organoleptically un accepted after 12 days of storage at 6+ 1 C, but they remain acceptable for 3 months at –18 C. Chemical Quality Attributes: - There were a increase in pH, TBA value and TVB-N of control, 30% and 40% potassium chloride treated samples during chilling storage. After 12th day of chilling storage all the samples were exceeding the maximum limit stated by the E.S.S. No. 1972 / 1991. Regarding frozen storage the pH remained nearly constant, while there were an increase in TBA value and TVB-N during the storage period. There were no significant differences (P>0.05) between control, 30% and 40% potassium chloride treated samples. Effect of Sodium Lactate: - Concerning organoleptic properties, sodium lactate preserves the colour, increase cooking yields all over the frozen storage period. In chilling storage 1.5% sodium lactate increase the shelf- life by about 3 days, while 3% sodium lactate increase the shelf life by one week. Regarding chemical quality attributes, addition of sodium lactate did not affect the initial pH, but it prevent pH decline during chilling storage. There were no significant differences between control 1.5% and 3% sodium lactate treated samples in relation to TBA value (P>0.5), while significant differences ( P< .05) were found between control and sodium lactate treated samples during refrigeration or frozen storage of sausage in relation to TVB-N. Microbiological Criteria There were significant differences between control, 1.5% and 3% sodium lactate treated samples in relation to APC, Psychrotrophic count, staph aureus count coliform (MPN) count, faecal coliform (MPN) count and mould and yeast count during chilling or frozen storage of experimentally produced sausage samples, there was an increase in microbial counts of all sausage treatment. During chilling storage. On the other hand aerobic plate count, psychrotrophic count, ,mould and yeast count increased during frozen storage, while Staph. aureus count coliforms (MPN) , faecal coliforms (MPN) decreased during frozen storage Bacillus cereus, E. coli, Salomenellae, and Y. enterocoltica could not be detected in all experimentally produced samples during either chilling or frozen storage.