Chicken By-products Research Articles

Physicochemical and Functional Properties of Chicken By-Products As A Source of Animal Feed

The purpose of this study was to determine the physicochemical and functional properties of chicken by-products, including head, feet, intestines and feathers that may be potential sources of animal feed. The chicken wastes are usually not converted into other useful products. Some issues present such as a bad smell, flies and dirt areas that can disrupt the impacts of the community and residents living nearby. The sample preparation was started by collecting samples from the slaughterhouse and stored under a temperature of 3-4 ⁰C before performing the analysis. The findings revealed which the chicken head and feet were higher in the percentage of protein (87.36%) and ash (4.46%) content. The intestines have higher moisture content (83.69%), fat (1.45%) and crude fiber (0.2%). The higher water absorption capacity was intestines (6.03 ml/ g) meanwhile, the feathers have a higher oil absorption capacity (8.36 ml / g) when compared to others. They had been determined the physicochemical and functional properties of chicken by-products and they have potential as a source of animal feed production.

85 Impacts of dietary profile on starch content and gelatinization in canine diets

Abstract Starch gelatinization of pet foods can be impacted by several factors, including moisture, retention time, and ingredients used. Starch gelatinization has been associated with effects on digestibility, but isn’t well studied in non-traditional canine diets. The objective of this research was to examine the impacts of dietary ingredient profile (traditional vs. non-traditional) and assess impacts to total starch content and starch gelatinization. Traditional diets (n = 10) utilizing meat-based ingredients including chicken, chicken byproduct meal, meat and bone meal and plant-based ingredients including rice, barley, oats, and corn were examined in comparison with non-traditional diets (n = 10) utilizing meat-based ingredients including alligator, buffalo, venison, kangaroo, squid, quail, rabbit, rabbit and salmon along with plant-based ingredients including tapioca, peas, chickpeas, lentils, potato, and pumpkin. Representative samples were collected via grab sample technique (5 samples/diet) and were assessed for total starch content as well as percent starch gelatinization. Variation between both diet types were assessed with a nonlinear regression using SAS 9.4. Significance was set at P < 0.05. Distribution of total starch content based on ingredient type (traditional vs non-traditional) reveal that mean total starch content is 15% higher in traditional diets as compared to non-traditional diets (P < 0.0001). Conversely, percent starch gelatinization was found to be 10% higher in non-traditional diets (P < 0.0001). Total starch content and percent gelatinization had a highly significant non-linear relationship (P < 0.0001). These novel data reveal important differences between starch content and gelatinization and could impact manufacturing processes for ingredient types as well as feeding recommendations.

Novel Pentapeptide Derived from Chicken by-Product Ameliorates DSS-Induced Colitis by Enhancing Intestinal Barrier Function via AhR-Induced Src Inactivation.

Managing patients with refractory inflammatory bowel diseases (IBD) is a common clinical challenge. Galli Gigeriae Endothelium Corneum (GGEC), a chicken by-product, has been used for centuries in Asian countries as a functional food and supplement for the treatment of gastrointestinal disorders. In this study, a novel peptide (LNLYP, LP-5) with gastrointestinal stability that can enhance the intestinal barrier function that was first identified in GGEC. Our work demonstrated that aryl hydrocarbon receptor (AhR) activation by LP-5 could inhibit the Src kinase to increase tight junction protein levels and down-regulate the expression of inflammatory cytokines to protect the intestinal barrier and finally alleviate dextran sulfate sodium (DSS)-induced colitis. This study revealed that LP-5 had the potential to develop into a therapeutic agent for the treatment of colitis and provided new high-valued utilization of GGEC.

К ВОПРОСУ ПОЛУЧЕНИЯ РЫБНЫХ ПАШТЕТОВ ПОВЫШЕННОЙ БИОЛОГИЧЕСКОЙ ЦЕННОСТИ

In the context of the organization of proper nutrition of the population of Russia, regardless of belonging to any physiological group, taking into account the eating behavior of a modern person, the research has been carried out to expand the range of fish pastes by modifying their recipes. The goal has been achieved by combining raw materials of different origins and reducing the mass fraction of table salt. Experimental studies were carried out to substantiate the recipe compositions of pastes based on grass carp meat, the optimal proportion of calcium-phosphate mineral supplements was defined, a comparative analysis of organoleptic indicators of quality, chemical composition and energy value of the obtained products was conducted. It has been stated that the introduction of 2.5% of phosphate-calcium food additives into paste recipes No. 4 and 
 5 did not adversely affect the organoleptic quality indicators. The pastes produced according to recipes No. 4 and No. 5, which include grass carp meat (48%), chicken liver (10%), vegetable components (17%), calcium-phosphate mineral supplement (2,5%) and flavoring substances, can be recommended for mass nutrition of the population of Russia. The ratio of these components provides the high organoleptic properties and improved nutritional value. The inclusion of fish pastes enriched with vegetable components, chicken by-products, phosphate-calcium mineral supplements, differing in chemical composition, in the diet allows balancing the diet for proteins, fats, amino acids, vitamins, macro- and micronutrients and preventing from eating disorders and, in the result, reducing morbidity of population in the Russian Federation.

Quality of Chicken Fat by-Products: Lipid Profile and Colour Properties.

The growth in the production and consumption of chicken meat and related products is responsible for the formation a large number of by-products. Among these, abdominal and gizzard fat is usually considered as waste and thus is discarded, creating an environmental problem. This work aims to characterize chicken fat by-products, evaluating their lipid profile and colour properties for their potential use as fat sources in meat products in substitution of traditionally used fats. In addition, the role of farm location, keeping the feeding and other farmer routines fixed, in the lipid profile was also evaluated. “Parrilleros” Colombian chickens from three farms located in various geographical zones of the Antioquia region were selected. After slaughtering, abdominal and gizzard fat was obtained. Lipid profile was evaluated by gas chromatography and the CIELAB colour properties were assessed. The production results and the lipid profile of chicken fat by-products (abdominal and gizzard fat) was similar in the three farms studied, which is important for their potential application as fat source in the formulation of meat products. The predominant fatty acids were oleic, palmitic and linoleic acids, showing a higher amount of unsaturated fatty acids than the fat sources traditionally used for this purpose. Valorization of chicken by-products by the use of abdominal and gizzard fat as fat source in chicken meat products formulation could be a feasible alternative contributing to the poultry sector sustainability.

Bromelia karatas and Bromelia pinguin: sources of plant proteases used for obtaining antioxidant hydrolysates from chicken and fish by-products

In the present study, we evaluated new sources of plant proteases from fruits of Bromelia karatas (BK) and Bromelia pinguin (BP) to obtain antioxidant hydrolyzates/bioactive peptides (BPs) derived from chicken by-products (CH) and fish by-products (FH). The profile of the peptides was identified by reverse-phase high-resolution liquid chromatography (RP-HPLC) and the size weight distribution by molecular exclusion chromatography (SEC). The hydrolysates obtained with BK in both sources of by-products showed greater antioxidant capacity compared to those obtained with BP, presenting similar or higher values when compared to a commercial plant enzyme. The use of new sources of plant proteases allowed to obtain hydrolysates of hydrophilic character with a high percentage (> 50%) of peptides with molecular weights < 17.5 kDa from chicken and fish by-products. Therefore, based on the results obtained in antioxidant capacity it is possible to consider the hydrolysates as potential ingredients, food additives, and pharmaceutical products.

Production and characterization of yeasts grown on media composed of spruce-derived sugars and protein hydrolysates from chicken by-products

BackgroundA possible future shortage of feed protein will force mankind to explore alternative protein sources that can replace conventional soymeal or fishmeal. Several large industrial organic side-streams could potentially be upgraded to feed protein using a fermentation process to generate single cell protein. Yeast is the most widely accepted microorganism for production of single cell protein, because of its superior nutritional quality and acceptability among consumers. Here, we have assessed the growth of four different yeasts, Cyberlindnera jadinii, Wickerhamomyces anomalus, Blastobotrys adeninivorans and Thermosacc® Dry (Saccharomyces cerevisiae), on media composed of enzymatically saccharified sulfite-pulped spruce wood and hydrolysates of by-products from chicken, and we have characterized the resulting yeast biomass.ResultsGenerally, the yeast grew very well on the spruce- and chicken-based medium, with typical yields amounting to 0.4–0.5 g of cell dry weight and 0.2–0.3 g of protein per g of sugar. B. adeninivorans stood out as the most versatile yeast in terms of nutrient consumption and in this case yields were as high as 0.9 g cells and 0.5 g protein per g of sugar. The next best performing yeast in terms of yield was W. anomalus with up to 0.6 g cells and 0.3 g protein per g sugar. Comparative compositional analyses of the yeasts revealed favorable amino acid profiles that were similar to the profiles of soymeal, and even more so, fish meal, especially for essential amino acids.ConclusionsThe efficient conversion of industrial biomass streams to yeast biomass demonstrated in this study opens new avenues towards better valorization of these streams and development of sustainable feed ingredients. Furthermore, we conclude that production of W. anomalus or B. adeninivorans on this promising renewable medium may be potentially more efficient than production of the well-known feed ingredient C. jadinii. Further research should focus on medium optimization, development of semi-continuous and continues fermentation protocols and exploration of downstream processing methods that are beneficial for the nutritional values of the yeast for animal feed.

Extraction and characterization of gelatin from black-bone chicken by-products.

In this study, gelatins from black-bone chicken feet and skin (BCFG and BCSG) were extracted using different NaOH concentrations, and their physicochemical properties were characterized and compared to commercial bovine gelatin (BG). It was found that the yield of BCFG was higher than BCSG, however, it contained higher amount of ash. All studied gelatins were composed of two distinct α-chains, while β-chain and γ-chain were not present. The BCFG and BCSG were found to have lower pH, lower hydroxyproline content and lower thermal stability, but higher gel strength as compared with the BG. The colors of BCSG and BCSG were slightly darker than BG. The NaOH concentration did not show strong influence on physicochemical properties of the extracted gelatins, however, thermal stability and gel strength of BCSG tended to decrease with increasing of NaOH concentration. These findings suggested that black-bone chicken feet and skin could be a great source for the production of gelatin.

Carcass Characteristics and Nutritional Composition of Some Edible Chicken By-products

The objective of this study was to evaluate the characteristics of chicken carcass and determine the nutritional composition of some edible chicken by-products, including liver, gizzard, wings, and skin. The total yield of liver, gizzard, wings and skin of chicken was found to be about 23.43%of carcass weight. The results showed that these chicken by-products are good sources of protein, fat, and minerals (ash). The greatest protein content was found to be 26.33% (wb) for wings; while, skin showed the greatest fat content of 34.48% (wb) compared with other by-products. On the other hand, liver showed the greatest ash content of 1.42% (wb) and skin showed the lowest ash content of 0.46% (wb). Moreover, the greatest caloric value of 362.36 Kcal/100 g was found for skin, followed by wings, liver, and gizzard. In addition, the results showed good contents of potassium, phosphorus, sodium, iron, and zinc in chicken by-products. These by-products were found to be a good source of essential amino acids such as leucine and lysine. Furthermore, liver, gizzard, wings, and skin of chicken showed greater unsaturated fatty acids content than that of saturated fatty acids. Oleic, linoleic, linolenic, and arachidonic acids are the most predominant unsaturated fatty acids found in these chicken by-products. However, palmitic and stearic acids are the predominant saturated fatty acids found in the studied chicken by-products. The obtained results revealed that the liver, gizzard, wings, and skin of chicken are rich of healthy nutrients; therefore, the utilization of these by-products as food should be promoted by development of new food products through the advances in meat processing techniques.

English

This study was performed to determine the prevalence of Campylobacter species in retail chicken meat and chicken by-product, determine their in vitro cytotoxicity, as well as, examine their susceptibility to different antimicrobials. A total of 300 raw chicken meat samples were collected from different retail chicken meat outlets located at Mansoura city, Egypt classified into 120 thighs, 120 breasts, and 60 livers. All samples were subjected to conventional culture techniques and confirmed as Campylobacter jejuni by real time polymerase chain reaction (PCR). Antimicrobial susceptibility of Campylobacter species was determined using disc diffusion method to determine their susceptibility to 12 different antimicrobial agents. In addition, C. jejuni isolates were examined for their cytotoxicity against Vero cells. The overall prevalence of Campylobacter spp. was 10.3% (31/300) classified into 20 (18.2%) C. jejuni and 11 (10.7%) Campylobacter coli. Among C. jejuni isolates (n=20), 15 strains belonged to biotype I and 5 isolates belonged to biotype II. The isolation rate from chicken thighs, breasts and livers was 12.5, 10 and 6.6%, respectively. A total of 15 (75%) C. jejuni strains revealed cytopathic effect (CPE) against Vero cells. Campylobacter spp. displayed a high antimicrobial resistance against penicillin G, gentamicin, trimethoprim-sulfamethoxazole, cephalothin, erythromycin, and chloramphenicol. On the other hand, Campylobacter spp. displayed high sensitivity to ciprofloxacin and nalidixic acid. Multidrug resistance was observed in 85 and 81.82% of C. jejuni and C. coli isolates, respectively High frequency of cytotoxicity and multidrug resistance in Campylobacter spp. from chicken meat indicates an important epidemiological role of Campylobacter spp. in human infections which necessitate proper hygienic measures on poultry farms and control measures during carcass slaughtering and processing. Key words: Campylobacter; retail chickens meat, real time polymerase chain reaction (PCR), cytotoxicity, antimicrobial susceptibility.

Proximate composition, bio-chemical and microbial quality of pet food prepared from chicken byproducts by incorporating cauliflower wastes

A study was under taken on preparation of pet food from chicken head (20 %), feet meal (15 %) and cauliflower waste meal (10 %). The proximate composition, chemical and microbial qualities were analysed. The proximate composition (%) viz., crude protein, ether extract, crude fibre, total ash, nitrogen free extract and metabolizable energy (K Cal/100g) of pet food on dry matter basis were 26.63, 18.52, 1.38, 10.29, 43.17 and 422.28, respectively. The thiobarbituric acid from 0.46 to 2.52 mg MA/kg, tyrosine value 35.53 to 77.36 mg/100g and total viable count log 3.46 to 5.90 cfu/g were increasing significantly (P&lt;0.01) and yeast and mould count was not detected up to 50 days of storage period. The pets were fed with prepared pet food and evaluated by pet owner gave score for appearance, consistency, odour which were in normal range and overall acceptability was good.

The Impact of Rendered Protein Meal Oxidation Level on Shelf-Life, Sensory Characteristics, and Acceptability in Extruded Pet Food

Simple SummarySensory analysis was used to determine the changes due to the storage time on extruded pet food prepared from two different rendered protein meals: (i) beef meat and bone meal (BMBM); (ii) chicken byproduct meal (CPBM). Extrusion is a process where feed is pressed through a die in order to create shapes and increase digestibility. Descriptive sensory analysis using a human panel found an increase in undesirable sensory attributes (e.g., oxidized oil, rancid) in extruded pet food over storage time, especially the one prepared from chicken by product meal without antioxidants. The small increase in oxidized and rancid aromas of BMBM samples did not affect pet owners’ acceptability of the products. CPBM samples without antioxidants showed a notable increase in oxidized and rancid aroma over storage time and, thus, affected product acceptability negatively. This finding indicated that human sensory analysis can be used as a tool to track the changes of pet food characteristics due to storage, as well as estimate the shelf-life of the products.Pet foods are expected to have a shelf-life for 12 months or more. Sensory analysis can be used to determine changes in products and to estimate products’ shelf-life. The objectives of this study were to (1) investigate how increasing levels of oxidation in rendered protein meals used to produce extruded pet food affected the sensory properties and (2) determine the effect of shelf-life on pet owners’ acceptability of extruded pet food diet formulated without the use of preservative. Pet food diets contained beef meat bone meal (BMBM) and chicken byproduct meal (CBPM) in which the oxidation was retarded with ethoxyquin, mixed tocopherols, or none at all, and then extruded into dry pet foods. These samples represented low, medium, and high oxidation levels, respectively. Samples were stored for 0, 3, 6, 9, and 12 months at ambient temperature. Each time point, samples were evaluated by six highly trained descriptive panelists for sensory attributes related to oxidation. Samples without preservatives were chosen for the acceptability test, since the differences in sensory characteristics over storage time were more distinguishable in those samples. Pet owners evaluated samples for aroma, appearance and overall liking. Descriptive sensory analysis detected significant changes in oxidized-related sensory characteristics over storage time. However, the differences for CBPM samples were more pronounced and directional. The consumer study showed no differences in pet owners’ acceptability for BMBM samples. However, the noticeable increase in aroma characteristics (rancid aroma 0.33–4.21) in CBPM samples over storage time did have a negative effect on consumer’s liking (overall liking 5.52–4.95).

Microbiological Evaluation of Pork and Chicken By-Products in South Korea

In this study, we aimed to evaluate the microbiological risk of pork and chicken by-products by enumerating indicator bacteria (total aerobic bacteria, coliforms, and Escherichia coli) and identifying pathogens such as Campylobacter and Salmonella. The antibiotic resistance of pathogenic isolates was determined, and molecular subtyping was performed using automated repetitive sequence-based PCR (rep-PCR). Pork and chicken by-products were collected from 10 processing plants. The mean numbers of total aerobic bacteria, coliforms, and E. coli from 95 pork by-product samples and 64 chicken by-product samples were 5.1, 3.6, and 2.4 log CFU/g and 4.5, 3.0, and 1.8 log CFU/g, respectively. The numbers of indicator bacteria in the gastrointestinal tract (small intestine, large intestine, and gizzard) were significantly higher than those in other organs. Salmonella and Campylobacter species were detected in 3 and 5 of 95 pork by-product samples and in 6 and 3 of 64 chicken by-product samples, respectively. Four of 9 Salmonella isolates examined were resistant to eight antibiotics, and each of these resistant strains produced an extended-spectrum β-lactamase. Most Campylobacter isolates were resistant to tetracycline (7 of 8 strains) and quinolones (7 of 8 strains). The similarity in rep-PCR patterns among Salmonella isolates was more closely associated with serotype than with the processing plant and type of meat. Conversely, the rep-PCR patterns of Campylobacter isolates were specific to the processing plant. Our findings could help agencies develop regulations for protection from foodborne bacterial infections arising from animal by-products.

Characterization of Chicken By-products by Mean of Proximate and Nutritional Compositions.

Though a great amount of chicken by-products are consumed everyday in many countries worldwide, however, no attention has been paid to the investigation of nutritional composition of these by-products. In the present work, the basic information regarding the aspects of nutritional composition of chicken by-products such as; liver, gizzard, heart, lung, crop, small intestines, cecum and duodenum was studied. Our results revealed that the approximate composition range (minimum to maximum) of these by-products was found as such: moisture 76.68-83.23%; fat 0.81-4.53%, protein 10.96-17.70% and calories 983.20-1,426.0 cal/g tissue, in which liver and gizzard had the highest protein content. Liver had higher (p<0.05) vitamin A, B1, B2, B3, B5 and B6 contents in comparison to other remaining by-products. Total saturated fatty acids (SFA), unsaturated fatty acids (UFA), polyunsaturated fatty acids (PUFA) levels ranged between the by-products from 31.82% to 43.96%, 56.04% to 68.19%, and 18.27% to 32.05%, respectively. Remarkably, all of by-products showed desirable PUFA/SFA ratios. Furthermore, all of chicken by-products, especially liver, contained higher levels of trace elements (e.g., Fe, Mn and Zn) in comparison with those from muscle tissues published in literature. Overall, the study indicated that most of chicken by-products examined are good sources of essential nutrients and these obtained results will be the useful information to consumers and meat processors.

Resource consumption assessment of Pangasius fillet products from Vietnamese aquaculture to European retailers

Concerns have risen regarding the environmental sustainability of favourable aquaculture-based products, including Pangasius fillets in modified atmosphere packaging (MAP). This study examines issues stemming from resource consumption in a cradle-to-factory gate life cycle analysis of MAP Pangasius, which includes aquaculture, processing living fish to frozen fillets in Vietnam, oceanic transport and processing frozen fillets to MAP in Belgium (Europe). Analysis was performed at the process level using Exergy Flow Analysis (ExFA) and from a life cycle perspective through the Cumulative Exergy Extraction from the Natural Environment (CEENE). The CEENE of MAP equals 669 GJ per tonne of dry matter (DM) of MAP Pangasius. Aquaculture, which is addressed in Huysveld et al. (2013), contains the largest share of the CEENE value (76%), and the three subsequent phases contribute 13%, 5% and 6%, respectively. Consequently, MAP production requires significant amounts of land (42%, primarily for the cultivation of crop-based feed ingredients), water (31%, primarily for pond water renewal) and fossil fuels (21%, primarily for energy demand in processing and transport). Regarding processing and transport, further attention should be paid to the consumption of electricity, water and packaging materials. Improvements should focus on lowering the fillet weight gain due to glazing and/or soaking and on the use and disposal of packaging materials, particularly those used to ship the frozen fillets. Recycling in Belgium reduces 40 GJ per tonne of DM of MAP via replacement of virgin material. MAP Pangasius creates half the resource footprint compared to fresh chicken meat locally produced in Europe despite being imported from Vietnam; this is explained by the lower Feed Conversion Ratio of Pangasius and by the utilization of Pangasius by-products for animal feed in Vietnam, whereas chicken by-products are considered wastes and are incinerated in Europe.

Utilization of Chicken By-Products to Form Collagen Films

Chicken collagen casings could be an alternate source of collagen casings that are manufactured for sausages. The overall objective of this project was to extract chicken collagen from by-products of the broiler processing industries and to explore the possibility of making films. Chicken skin was washed, ground, and pretreated to remove the noncollagenous compounds. Collagen was extracted using acetic acid and pepsin. Solubilized collagen was salted-out and centrifuged at 20,000 ×g at 4°C for one hour. The precipitates were dissolved in 0.5 M acetic acid and dialyzed against 0.1 M acetic acid and distilled water before freeze-drying. Molecular weight, collagen solubility at different pH values, and NaCl concentrations were determined. TA-XT2 texture analyzer was used to characterize mechanical properties of collagen films. The highest collagen solubility was obtained at pH 2 and 2% NaCl. Hand-homogenized, nonfiltered, and conditioned samples had the highest hardness (3,262 g) and the least brittleness (30.5 mm). These results demonstrate that chicken collagen extracted from chicken by-products has the ability to form films and could be considered for making casings or be used in various other industries.

Chicken Collagen from Law Market Value By-Products as an Alternate Source

There has been much interest in investigating possible means of making collagen from underutilized chicken by-products and it will lead to an alternate source of collagen for use in various industries such as pharmaceuticals, cosmetics, biomedical materials, and the food industry. The objective of this research was to find methods to extract collagen from chicken skins and bones to compare the corresponding yield differences and analyze their properties. Collagen extracted by acetic acid, citric acid, alkali, one-step acetic acid and pepsin, and two-step acetic acid and pepsin extraction procedures was compared. Complete randomized design, Student’st-test, and Tukey’s test were used to analyze the samples(P&lt;0.05). The recovered dry weights for the skin extractions were 6.1, 6.2, 5, 38.7, and 40.4% and those of bone extractions were 4.4, 4.1, 4.1, 19.1, and 20.6%, respectively. Protein, fat, and inorganic material contents of collagen preparations for skin were 62.7%, 1.5%, and 0.7% and for bone were 30.4%, 1.4%, and 0.7%, respectively. This study indicates that chicken by-products have high potential use as an alternate source of collagen.Corrigendum to “Chicken Collagen from Law Market Value By-Products as an Alternate Source”

Potential of chicken by-products as sources of useful biological resources

By-products from different animal sources are currently being utilised for beneficial purposes. Chicken processing plants all over the world generate large amount of solid by-products in form of heads, legs, bones, viscera and feather. These wastes are often processed into livestock feed, fertilizers and pet foods or totally discarded. Inappropriate disposal of these wastes causes environmental pollution, diseases and loss of useful biological resources like protein, enzymes and lipids. Utilisation methods that make use of these biological components for producing value added products rather than the direct use of the actual waste material might be another viable option for dealing with these wastes. This line of thought has consequently led to researches on these wastes as sources of protein hydrolysates, enzymes and polyunsaturated fatty acids. Due to the multi-applications of protein hydrolysates in various branches of science and industry, and the large body of literature reporting the conversion of animal wastes to hydrolysates, a large section of this review was devoted to this subject. Thus, this review reports the known functional and bioactive properties of hydrolysates derived from chicken by-products as well their utilisation as source of peptone in microbiological media. Methods of producing these hydrolysates including their microbiological safety are discussed. Based on the few references available in the literature, the potential of some chicken by-product as sources of proteases and polyunsaturated fatty acids are pointed out along with some other future applications.

Extraction, isolation and analysis of chondroitin sulfate from broiler chicken biomass

This study was undertaken to investigate whether chondroitin sulfate (CS) can be efficiently isolated from broiler chicken by-product from mechanical deboning (BMD), which is a mixture of crushed bone, cartilage, skin, adipose tissue and muscle. With BMD as a starting material, it may be possible to maximize CS production from chicken cartilage. CS was liberated from BMD by proteolysis using proteolytic activities from papain, pancreatin, kiwi fruits and flavourzyme. The final product isolated by anion-exchange chromatography and differential precipitation with varying concentrations of ethanol contained CS-peptides with glucuronosyl-N-acetylgalactosamine-4-sulfate as a predominant disaccharide. All the enzyme sources used had sufficient activities to produce CS-peptides with undetectable amount of glucosamine. However, the size of peptide attaching to CS chain and the antigenicity to anti-keratan sulfate (KS) monoclonal antibody varied among the CS-peptides prepared with different proteinases. Papain digestion resulted in the smallest size of peptide with no detectable antigenicity to the anti-KS antibody. In contrast, pancreatin digestion provided CS-peptide having a very weak but positive antigenicity to the anti-KS antibody, which was much lower than that seen with CS-peptide prepared with kiwi fruit proteinase or flavourzyme. Pancreatin is suggested as an economical source of proteinase to liberate CS-peptides from BMD.

MPN-PCR enumeration of Campylobacter spp. in raw chicken meats and by-products

The goal of this study is to enumerate Campylobacter in chicken meats and by-products. In the current investigation, results showed that raw chicken meats and chicken by-products were contaminated with Campylobacter ranging from <3 to 4600 MPN·g−1. Campylobacter jejuni showed a higher number compared to Campylobacter coli in the chicken samples. The current study showed that the percentage of chicken livers and gizzards harbored a higher number of Campylobacter (103–104 MPN·g−1) than other chicken parts at 33.3% and 9.2%, respectively. The different concentrations of Campylobacter between chicken meats and chicken byproducts reflect the differences in the contamination level. The data on Campylobacter concentration in chicken meats and by-products will be useful in risk analysis.