The effects of washing treatments and washing cycles on the thermal gelation properties and quality
characteristics of duckrimi (duck-base surimi-like material) were evaluated. Minced spent layer duck (4.5 mm orifice diameter) were washed by using either tap water, 0.1M NaCl, 0.5% NaHCO3 and 0.04M sodium phosphate in one, two or three washing cycles, respectively. Washing with 0.04M sodium phosphate in three washing cycles significantly increased (P
The aim of this study was to produce a high-protein, wet yellow noodle by the incorporation of surimi powder as a protein source and evaluate the effects of the physicochemical and sensory properties of the
noodle. The surimi powder was prepared by oven drying the wet surimi at 60oC until the moisture content was below 10%. Five concentration levels of surimi powder substitutions were used (0, 5, 10, 15 and 20%), and as a result, the noodles showed a trend that significantly increased (P
Surimi refers to concentrated myofibrial protein extracted from fish flesh by washing process. Surimi powder, is normally prepared in a dried form, and potentially useful as a raw material for preparation of seafood products. Surimi powder offers many advantages in industrial application, such as easy handling, low distribution cost, and physically convenient for addition to dry mixtures. In order to prevent the denaturation of the protein during drying, dryoprotectants such as sucrose and polyols can be added. Surimi powder is classified as fish protein concentrate type A because its protein content is higher than 65%. Surimi powder has good functional properties, such as gelation, water holding capacity, and emulsifying and foaming properties. Gel-based fish products and fish snacks are common products that can be made from surimi powder.
Yellowfin tuna (Thunnus albacares) wastes were used to recover of tuna frame (TF) and to extract of tuna bone powder (TBP) by alkaline treatment. The amount of the calcium with 24.56% and 38.16% was the most abundant element in TF and TBP, respectively. Nine essential amino acids for human body; lysine, valine, leucine, isoleucine, methionine, threonine, histidine, phenylalanine and tryptophan are detected in TF and TBP. The amount of the collagen associated amino acids such as glycine, proline and hydroxyproline were high and the amount of glutamic acid, arginine, alanine, aspartic acid and serine were relatively more. The amount of the oleic acid, palmitic acid and gondoic acid were higher and the amount of hexadecatrienoic acid, γ-linolenic acid and dihomo-γ-linolenic acid were lower. The amount of the myristic acid, stearic acid, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were also relatively more. Results demonstrated that TBP as inexpensive and environmentally friendly alternative source of calcium can be converted to the healthy value added products to increase of the amount of the calcium intake among people especially population groups with lactose intolerance.
The objective of this study was to evaluate the effects of using tapioca and sago flours with or without egg white powder (EWP) on the physicochemical and sensory properties of duck sausages. There was significant increase (P0.05) in hardness and cohesiveness attributes among all the samples examined but significant differences (P
Protein-rich by-products from the canning industry, especially dark flesh of skipjack, have limited uses due to several factors such as darken color, susceptibility to oxidation and off flavour. Protein hydrolysates from skipjack dark flesh was produced with different type of industrial proteases (Alcalase®2.4L FG, Protamex®, Neutrase®1.5MG and Flavourzyme®500MG) for 60, 120, 180 and 240 min with level of proteases used of 0.5, 1, 1.5 and 2% per weight of raw material. The degree of hydrolysis and free tryptophan content of hydrolysate were investigated. The results shows longer time with higher concentration of enzyme has increased the degree of hydrolysis. Alcalase®2.4L FG had the highest degree of hydrolysis among all proteases followed by Protamex®, Flavourzyme®500MG and Neutrase® 1.5MG. All enzymes increase free tryptophan content linearly with the increament of protease enzyme level. The longer the hydrolysis time, the higher the content of free tryptophan produced.
Fifty five (n=55) isolates of Escherichia coli isolated from ducks in Penang, Malaysia were examined for their susceptibility to eleven different antibiotics and assayed for the presence of plasmid DNAs. All the 55 Escherichia coli isolates were resistant (100%) to vancomycin. Higher resistance (= 60) occurred for tetracycline 51 (92.7%), ampicillin 40 (72.7%), streptomycin 37 (67.3%), and sulfamethoxazole-trimethophrim 37 (67.3%). No and low resistance was observed for nitrofurantoin (0%) and gentamicin (1.8%), respectively. The isolates also showed some intermediate resistances to all antibiotics examined except for vancomycin. The 55 Escherichia coli isolates exhibited 23 different antibiotic resistant patterns with MAR index ranging from 0.09-0.82. Majority of the Escherichia coli isolates exhibited resistant pattern of VA-C-OFX-SXT-TE-AMP-NA-KF and VA-S-C-OFX-SXT-TE-AMP-NA-KF with MAR index of 0.73 and 0.82, respectively. The smallest plasmid DNA size was 1.2 kb and the largest plasmid DNA size was 81.5 kb. 51 (93%) of the duck Escherichia coli isolates harbored plasmids. The was no direct correlation between plasmid DNA sizes and antibiotic resistant among the duck Escherichia coli isolates. Thus, the antibiotic resistant of the Escherichia coli isolates could mostly be mediated by chromosomes instead of plasmids. This study also suggests that the use of antibiotics in duck farming in Penang, Malaysia needs to be controlled to prevent the spread of multiple antibiotic resistant Escherichia coli isolates.
Burgers were prepared using duck surimi-like material (DSLM) with polydextrose added (SL) and DSLM with sucrose-sorbitol added (SS), and the properties of these burgers were compared with those of burgers made of chicken meat (CB) and duck meat (DB). Quality characteristics such as chemical composition, cooking loss, diameter shrinkage, color, and texture were measured. The DB had a lower moisture content (55.58%) and higher fat content (21.44%) and cooking loss (11.01%) compared with other samples, whereas CB, SS, and SL did not differ significantly in moisture (65.21-66.10%) and fat (10.42-11.16%) content or cooking loss (5.32-6.15%). The SS and SL were positioned below CB and above DB in terms of hardness, chewiness, and springiness. Ten trained panelists assessed the burgers using quantitative descriptive analysis. Among the burgers, CB had the greatest brightness of color, hardness, springiness, and chewiness. The SS had greater sweetness than the other burgers. Both SL and SS had significantly less animalic odor, meaty flavor, oiliness, juiciness, and saltiness compared with DB. The physicochemical and sensory characteristics of burgers prepared from DSLM approached those of burgers made of chicken.
In this study, the effect of the addition of different cryoprotectants on the freeze-thaw stability of duck surimi-like material (DSLM) was tested. A 6% (wt/wt) low-sweetness cryoprotectant (i.e., polydextrose, trehalose, lactitol, or palatinit) was added to a 3-kg portion of DSLM, and the mixture was subjected to freeze-thaw cycles during 4 mo of frozen storage. The DSLM with no cryoprotectant added (control) and with a 6% sucrose-sorbitol blend (high-sweetness cryoprotectant) added also were tested. The polydextrose-added sample had the highest water-holding capacity among the sample types tested (P < 0.05), and it retained its higher value during frozen storage. The protein solubility of the cryoprotectant-added samples decreased significantly (P < 0.05) from 58.99 to 59.60% at initial frozen storage (0 mo) to 48.60 to 54.61% at the end of the experiment (4 mo). The gel breaking force of all samples significantly decreased (P < 0.05) at 1 mo; this breaking force then stabilized after further frozen storage for the cryoprotectant-added samples, whereas it continued to decrease in the control samples. Gel deformation fluctuated during frozen storage and was significantly lower (P < 0.05) at the end of experiment than at the beginning. The presence of cryoprotectants reduced the whiteness of DSLM. Samples containing polydextrose, trehalose, lactitol, and palatinit were able to retain the protein solubility, gel breaking force, and deformation of DSLM better than control samples after 4 mo of frozen storage and exposure to freeze-thaw cycles. The effects of these low-sweetness cryoprotectants are comparable to those of sucrose-sorbitol, thus, these sugars could be used as alternatives in protecting surimi-like materials during frozen storage.
The gelation properties of spent duck meat surimi-like material produced using acid solubilization (ACS) or alkaline solubilization (ALS) were studied and compared with conventionally processed (CON) surimi-like material. The ACS process yielded the highest protein recovery (P < 0.05). The ALS process generated the highest lipid reduction, and the CON process yielded the lowest reduction (P < 0.05). Surimi-like material produced by the CON process had the highest gel strength, salt extractable protein (SEP), and water holding capacity (WHC), followed by materials produced via the ALS and ACS processes and untreated duck meat (P < 0.05). The material produced by the CON process also had the highest cohesiveness, hardness, and gumminess values and the lowest springiness value. Material produced by the ACS and ALS processes had higher whiteness values than untreated duck meat gels and gels produced by the CON method (P < 0.05). Surimi-like material produced using the ACS and CON processes had significantly higher myoglobin removal (P < 0.05) than that produced by the ALS method and untreated duck meat. Among all surimi-like materials, the highest Ca(2+)-ATPase activity was found in conventionally produced gels (P < 0.05). This suggests that protein oxidation was induced by acid-alkaline solubilization. The gels produced by ALS had a significantly lower (P < 0.05) total SH content than the other samples. This result showed that the acid-alkaline solubilization clearly improved gelation and color properties of spent duck and possibly applied for other high fat raw material.
The physicochemical properties and sensory analysis of duck meatballs containing duck meat surimi-like material during frozen storage were evaluated. Properties of meatballs containing duck surimi-like material prepared by acid solubilization (ACDS), alkaline solubilization (ALDS), and conventional processing (CDS) as well as duck mince (as the control, CON) were compared. ACDS had significantly higher (P < 0.05) moisture and protein content and lower fat content compared with CON. The thiobarbituric acid-reactive substances (TBARS) value of all samples increased as the storage time increased up to week 8 (P < 0.05), but thereafter it decreased in most of the samples. ACDS and ALDS had significantly higher TBARS values (P < 0.05), and these values remained higher than those of the other samples throughout the frozen storage period. Addition of surimi-like material to the meatballs had significant effects (P < 0.05) on springiness, gumminess, and chewiness values of all samples. Ingredients and frozen storage affected most sensory attributes in samples significantly (P<0.05). No significant increase in growth of organisms occurred during 12-wk frozen storage The results indicate that acid-alkaline solubilization methods improve both physicochemical and sensory properties of duck meatballs containing duck surimi-like material. Thus, these techniques should be applicable to product development of duck surimi-like material.
Duck feet collagen was added to threadfin bream and sardine surimi to study its effect on physicochemical properties such as folding test, gel strength, cook loss, water holding capacity, expressible moisture, texture profile analysis and colour measurement. As compared to commercial fish scale collagen and cow collagen, the addition of duck feet collagen resulted in a significant improvement in the quality of the sardine surimi. Duck feet collagen was able to improve the folding test score of sardine surimi from 3.00 to 5.00; gel strength was increased from 275.70 g.mm to 2682.70 g.mm and hardness of gel was increased from 1.12kg to 6.00kg. Addition of duck feet collagen improved the gel strength of threadfin bream surimi from 1696.70 g.mm to 5579.40 g.mm and hardness of gel was increased from 4.55kg to 10.32kg. Colour of threadfin bream and sardine surimi also improve with the addition of duck feet collagen. The lightness was increased from 66.47 to 66.89 (threadfin bream) and from 62.32 to 63.60 for sardine. The results suggest that duck feet collagen has potential as an alternative source of protein additive for the improvement of the physicochemical properties of low grade surimi.
The effects of different types of low-sweetness sugar (lactitol, maltodexrin, palatinit, polydextrose,
trehalose) on the physicochemical properties of threadfin bream (Nemipterus spp.) surimi during six months of frozen storage were investigated. The characteristics analyzed were moisture content, pH, water-holding capacity, whiteness, folding test, gel strength, expressible moisture, and texture profile analyses. Generally, the cryoprotective effectiveness decreased as the storage time increased. Polydextrose was able to maintain a water-holding capacity of 77.0%, 98.6% whiteness, a folding test value of 100%, and a gel strength of 53.6% compared with its initial value during six months of frozen storage. Meanwhile, sucrose was able to maintain a water-holding capacity of 80.3%, 98.6% whiteness, a folding test value of 75%, and a gel strength of 56.8%
compared with its initial value. Raw surimi was able to maintain water holding capacity of 62.2%, 98.7% whiteness, a folding test value of 75%, and a gel strength of 36.0% compared with its initial value. It is suggested that, polydextrose as a potential alternative cryoprotectant to replace other low-sweetness sugars.
The objectives of this study were to determine the physicochemical properties and sensory characteristics of fish sausage made with 100 % threadfin bream (Nemipterus japonicus) surimi powder (SP100), a mix of 50 % surimi powder and 50 % frozen surimi (SP50), and a control (100 % frozen surimi). No significant differences in protein content and folding test results (P > 0.05) were detected among the SP100 and SP50 samples and the control. Gel strength of SP100 was lower (P > 0.05) than that of the control. The texture profile analysis (TPA) values (hardness, cohesiveness, springiness, and chewiness) of SP100 were significantly lower (P
Duck meat is less utilized than other meats in processed products because of limitations of its functional properties, including lower water holding capacity, emulsion stability, and higher cooking loss compared with chicken meat. These limitations could be improved using surimi technology, which consists of washing and concentrating myofibrillar protein. In this study, surimi-like materials were made from duck meat using two or three washings with different solutions (tap water, sodium chloride, sodium bicarbonate, and sodium phosphate buffer). Better improvement of the meat's functional properties was obtained with three washings versus two washings. Washing with tap water achieved the highest gel strength; moderate elevation of water holding capacity, pH, lightness, and whiteness; and left a small amount of fat. Washing with sodium bicarbonate solution generated the highest water holding capacity and pH and high lightness and whiteness values, but it resulted in the lowest gel strength. Processing duck meat into surimi-like material improves its functional properties, thereby making it possible to use duck meat in processed products.
Campylobacter, Salmonella, and Listeria monocytogenes are important bacterial pathogens associated with gastroenteritis. The consumption of poultry meat and their products is considered as a major and leading source of human infection. While surveys of chicken meat and products, and its association with foodborne pathogens are widely available, such information on ducks is scarce. This survey examines the prevalence and antibiotic resistance of Campylobacter, Salmonella and L. monocytogenes isolated from ducks. Data obtained from key surveys are summarized. The observed prevalence of these pathogens and their resistance to various antibiotics varies from one study to the other. The mean prevalence (and range means from individual surveys) are duck 53.0% (0.0-83.3%), duck meat and parts 31.6% (12.5-45.8%), and duck rearing and processing environment 94.4% (92.0-96.7%) for Campylobacter spp. For Salmonella spp., the mean prevalence data are duck 19.9% (3.3-56.9%), duck meat and parts 28.4% (4.4-75.6%), duck egg, shell, and content 17.5% (0-4.17%), and duck rearing and processing environment 32.5% (10.5-82.6%). Studies on the prevalence and antibiotic resistance of L. monocytogenes in ducks are by far very rare compared to Campylobacter and Salmonella, although ducks have been noted to be a potential source for these foodborne pathogens. From our survey, ducks were more frequently contaminated with Campylobacter than Salmonella. Campylobacter and Salmonella spp. also exhibited varying resistance to multiple antibiotics.
The nutritional properties of surimi-like materials produced from spent duck meat processed conventionally (CDS) and processed with acid and alkaline solubilization (ACDS and ALDS, respectively) were studied. The essential amino acids (EAAs) content was significantly higher (p
Avoidance of dairy products due to lactose intolerance can lead to insufficiency of calcium (Ca) in the body. In an approach to address this problem, tuna bone powder (TBP) was formulated as a calcium supplement to fortify bakery products. In a study, TBP recovered by alkaline treatment contained 38.16 g/100 g of calcium and 23.31 g/100 g of phosphorus. The ratio of Ca:P that was close to 2:1 was hence comparable to that in human bones. The availability of calcium in TBP was 53.93%, which was significantly higher than most calcium salts, tricalcium phosphate (TCP) being the exception. In vitro availability of calcium in TBP-fortified cookies or TCP-fortified cookies were comparable at 38.9% and 39.5%, respectively. These values were higher than the readings from TBP-fortified bread (36.7%) or TCP-fortified bread (37.4%). Sensory evaluation of bakery products containing TBP or TCP elicited comparable scores for the two additives from test panels. Hence, TBP could be used in the production of high calcium bakery products that would enjoy consumer acceptance.
The main problem of landfill leachate is its diverse composition comprising many persistent organic pollutants which must be removed before being discharge into the environment. This study investigated the treatment of raw landfill leachate using electrocoagulation process. An electrocoagulation system was designed with iron as both the anode and cathode. The effects of inter-electrode distance, initial pH and electrolyte concentration on colour and COD removals were investigated. All these factors were found to have significant effects on the colour removal. On the other hand, electrolyte concentration was the most significant parameter affecting the COD removal. Numerical optimization was also conducted to obtain the optimum process performance. Under optimum conditions (initial pH: 7.73, inter-electrode distance: 1.16 cm, and electrolyte concentration (NaCl): 2.00 g/L), the process could remove up to 82.7% colour and 45.1% COD. The process can be applied as a pre-treatment for raw leachates before applying other appropriate treatment technologies.
Meat is an important food source that can provide a significant amount of protein for human development. The occurrence of bacteria that are resistant to antimicrobials in meat poses a public health risk. This study evaluated the occurrence and antimicrobial resistance of E. coli (Escherichia coli) isolated from raw meats, ready-to-eat (RTE) meats and their related samples in Ghana. E. coli was isolated using the USA-FDA Bacteriological Analytical Manual and phenotypic antimicrobial susceptibility test was performed by the disk diffusion method. Of the 200 examined meats and their related samples, 38% were positive for E. coli. Notably, E. coli was highest in raw beef (80%) and lowest in RTE pork (0%). The 45 E. coli isolates were resistant ≥ 50% to amoxicillin, trimethoprim and tetracycline. They were susceptible to azithromycin (87.1%), chloramphenicol (81.3%), imipenem (74.8%), gentamicin (72.0%) and ciprofloxacin (69.5%). A relatively high intermediate resistance of 33.0% was observed for ceftriaxone. E. coli from raw meats, RTE meats, hands of meat sellers and working tools showed some differences and similarities in their phenotypic antimicrobial resistance patterns. Half (51.1%) of the E. coli isolates exhibited multidrug resistance. The E. coli isolates showed twenty-two different resistant patterns, with a multiple antibiotic resistance index of 0.0 to 0.7. The resistant pattern amoxicillin (A, n = 6 isolates) and amoxicillin-trimethoprim (A-TM, n = 6 isolates) were the most common. This study documents that raw meats, RTE meats and their related samples in Ghana are potential sources of antimicrobial-resistant E. coli and pose a risk for the transfer of resistant bacteria to the food chain, environment and humans.