Feasibility of Enzymatic Protein Extraction from a Dehydrated Fish Biomass Obtained from Unsorted Canned Yellowfin Tuna Side Streams: Part II

The enzymatic extraction of proteins from fish biomasses is being widely investigated. However, little or almost no research has paid attention to the exploitation of unsorted fishery biomasses. This work is part of a larger study, Part I of which has already been published, and focuses on an extensive characterization of two collagenous samples, namely gelatin (G) and hydrolyzed gelatin peptides (HGPs), extracted from a dehydrated fish biomass coming from unsorted canned yellowfin tuna side streams. The results indicate crude protein fractions of 90-93%, pH values between 3 and 5, white-yellow colors, collagen-like FTIR spectra, and 17% in terms of total amino acid content. Viscosity and the study of dynamic viscous-elastic behavior were analyzed. Thermo-gravimetric analysis was performed to assess the residual ashes. Both samples were investigated to determine their molecular weight distribution via size-exclusion chromatography, with a higher total average molecular weight for G compared to HGPs, with values of 17,265.5 Da and 2637.5 Da, respectively. G demonstrated technological properties similar to analogous marine gelatins. HGPs demonstrated antioxidant activity as per FRAP assay. All the results open up new perspectives for the potential use of these substances in biodegradable packaging, dietary supplements, and skin care cosmetics.

Feasibility of Enzymatic Protein Extraction from a Dehydrated Fish Biomass Obtained from Unsorted Canned Yellowfin Tuna Side Streams: Part I

This study presents for the first time a scalable process for the extraction of valuable proteins starting from samples of unsorted mixed tuna scraps which were previously dehydrated by an industrial patented process. The aims of this work were both to avoid the onerous sorting step of tuna leftovers, which generally consists of isolating skin and bones for collagen/gelatin extraction, and to improve the logistic of managing highly perishable biomass thanks to the reduction in its volume and to its microbiological stabilization. In view of a zero-waste economy, all the protein fractions (namely, non-collagenous proteins NCs and ALKs, gelatin, and hydrolyzed gelatin peptides, HGPs) isolated in the proposed single cascade flowchart were stabilized and preliminarily characterized. The extraction flowchart proposed allows one to obtain the following most promising compounds: 1.7 g of gelatin, 3.2 g of HGPs, and 14.6 g of NCs per 100 g of dehydrated starting material. A focus on oven-dried gelatin was reported in terms of proximate analysis, amino acid composition, color parameters, FT-IR spectrum, pH, and viscoelastic properties (5 mPa·s of viscosity and 14.3 °C of gelling temperature). All the obtained extracts are intended to be exploited in food supplements, feed, fertilizers/plant bio-stimulants, packaging, and the cosmetic industry.

Comparison of the edible quality of liquid egg with different cooking methods and their antioxidant activity after in vitro digestion

The purpose of this study was to compare the edible quality of liquid egg after steaming, baking, frying and microwaving. Texture profile analysis (TPA) and color analysis were used to evaluate the sensory characteristics of cooked eggs. The fat, vitamin A and E, protein and amino acid content of cooked eggs and the antioxidant activity after in vitro digestion were determined to display the variations in nutritional value. TPA results demonstrate that baked egg exhibited a softer and more elasticity texture, with a significant lower hardness of 3234 g than fried and microwaved eggs (p < 0.05). This is also consistent with the results of cohesiveness and chewiness. Consequences from scanning electron microscope showed plentiful honeycomb structure in baked egg, which may be related to the soft and elasticity texture. However, significantly higher contents of fat, vitamins A and E, protein were determined in fried egg (p < 0.05), which may be related to its lower moisture content. The strongest free radical scavenging efficiency for the hydroxyl, the DPPH and the superoxide radical were found in the gastrointestinal digestion of fried egg, with the rate of 95.76%, 81.08%, and 91.08%, respectively. Overall, baked egg showed superior soft and elasticity taste characteristics due to its honeycomb structure, while fried egg exhibited better antioxidant activity because of its high contents in vitamins and amino acids. The above results provide potential approach for the manufacture of pre-cooked eggs and related products using liquid eggs as ingredients.

Low-sodium dry-cured rabbit leg: A novel meat product with healthier properties

Dry-cured rabbit legs were produced with a 50% reduction or replacement of NaCl by KCl and with the addition of monosodium glutamate (MG). The effect of this reformulation on technological, nutritional, and sensory characteristics was evaluated. The sodium reformulation did not show a great impact on Aw, pH, weight loss, and volatile profile of the samples. The samples presented high protein (31.5 to 36.1%) and low fat contents (3.2 to 5.7%). In addition, all essential amino acids presented an amino acid score greater than 1.0. The reformulated samples showed a sodium reduction of 46.2% while the addition of KCl to the formulations provided a healthy Na/K ratio. Oleic acid was the major fatty acid (FA) (31.3% of total FA) and healthy lipid indexes were observed for all samples. Finally, the addition of MG was effective to compensate for the sensory defects caused by sodium reformulation.

Effects of pulses and microalgal proteins on quality traits of beef patties

Physicochemical parameters (pH, colour and texture), proximate composition (moisture, protein, lipid and ash content), amino acid content, and taste profile of beef patties elaborated with soy (control), pulses (pea, lentil and bean) and microalgal (Chlorella and Spirulina) proteins were assessed. The pH, colour, ash content, total, essential and non-essential amino acids and amino acid content were significantly different among the beef patties studied. In this regard, beef patties prepared with pea protein presented the highest values for pH; whereas beef patties manufactured with pea also showed the highest values for lightness and patties elaborated with bean the highest values for redness. Similar textural parameters were observed among the six batches of beef patties manufactured. Regarding ash content, a significant higher content was observed in the beef patties prepared with soy compared to the other ones. On the other hand, the beef patties elaborated with bean and seaweeds showed the highest values for the total amino acids content. The inclusion of bean and seaweed proteins increased the concentrations of all amino acids in beef patties, being glutamic acids, lysine and aspartic acid the predominant amino acids. Regarding the taste analysis, a similar profile was found among the six batches of beef patties studied. Considering all studied parameters, beef patties elaborated with bean protein could be used as an alternative protein source respect to soy protein because of it showed a similar nutritional content and taste profile and higher amino acid content.

Change of the structure and the digestibility of myofibrillar proteins in Nanjing dry-cured duck during processing

BACKGROUND

To investigate the change of bioavailability and structure of myofibrillar proteins during Nanjing dry-cured duck processing, carbonyl content, sulfhydryl (SH) group, disulfide (SS) group, sodium dodecyl sulfate polyacrylamide gel electrophoresis, surface hydrophobicity, secondary structures and in vitro digestibility were determined.

RESULTS

During processing, carbonyl content and surface hydrophobicity increased; SH turned into SS group; α-helix turned into β-sheet and random coil fractions. Protein degradation occurred during dry-curing and drying-ripening stages. The in vitro digestibility of pepsin and pancreatic proteases increased during the salt curing stage and decreased during the drying-ripening stage.

CONCLUSION

The increase of digestibility could be attributed to the mild oxidation, degradation and unfolding of proteins while the decrease of digestibility was related to the intensive oxidation and aggregation of proteins. Protein degradation was not a main factor of digestibility during the drying-ripening stage. Results demonstrated that the bioavailability loss of myofibrillar proteins in Nanjing dry-cured duck occurred during the stage of drying-ripening instead of curing. © 2017 Society of Chemical Industry.

Effect of gender on breast and thigh turkey meat quality

1. The influence of gender on chemical composition, physicochemical parameters, fatty acid profile, amino acid and mineral composition of turkey breast and thigh meat was studied in order to assess nutrient requirements. 2. Chemical composition showed that only intramuscular fat in breast meat was significantly affected by gender (p < 0.05). The results showed a higher percentage of intramuscular fat in male samples, almost double the amount found in females (0.73% vs. 0.38%). 3.For meat colour parameters, only a* showed different results between sexes, with male samples (breast: p < 0.01; thigh: p < 0.001) having the highest values. 4. Fatty acid profiles showed that medium chain unsaturated fatty acids were the most abundant. The significant differences (p < 0.05) found in both breast and thigh muscle could be linked to a difference in metabolism between males and females. 5.There were higher levels of C16:1n-7 in females (breast: p < 0.001; thigh: p < 0.01) compared with male muscle sample (5.05 vs. 2.67 g/100 g in breast and 4.95 vs. 3.27 g/100 g in thigh). Nutritional indices (n-6/n-3 and thrombogenic index) were more favourable in female samples demonstrating that female turkeys had better fatty acid profile than the others. 6. Turkey meat is an important source of dietary amino acids, and female samples had the highest contents both of essential and non-essential amino acids. Furthermore, gender had a numeric effect (p > 0.05) on amino acid composition. 7. Mineral composition showed that Na, Zn and Fe were the minerals most affected by turkey gender.

Impact of the soy protein replacement by legumes and algae based proteins on the quality of chicken rotti

The addition of different protein sources (soy, bean, lentil, broad bean, Spirulina, and Chlorella) on nutritional, physicochemical and sensory properties of chicken rotti was evaluated. Significant changes were observed in physicochemical composition, textural properties and amino acid content of chicken rotti after adding the proteins from different sources, thus influencing the sensory acceptance and preference. Spirulina and Chlorella rotti presented a slight increase of pH and seaweed caused a decrease in some colour parameters. The highest lipids contents were found in chicken rotti added of with Spirulina and lentil proteins. Chicken rotti prepared with lentil protein also showed the highest values for ash content. Chicken rotti enriched with seaweed protein presented the highest total amino acid content. Principal component analysis showed that broad beans and lentils proteins as interesting ingredients to replace soy protein in chicken rotti.

Proximate Composition and Nutritional Value of Three Macroalgae: Ascophyllum nodosum, Fucus vesiculosus and Bifurcaria bifurcata

Proximate composition (moisture, protein, lipid and ash content) and nutritional value (fatty acid, amino acid and mineral profile) of three macroalgae (Ascophyllum nodosum, Fucus vesiculosus and Bifurcaria bifurcate) were studied. Chemical composition was significantly (p < 0.001) different among the three seaweeds. In this regard, the B. bifurcata presented the highest fat content (6.54% of dry matter); whereas, F. vesiculosus showed the highest protein level (12.99% dry matter). Regarding fatty acid content, the polyunsaturated fatty acids (PUFAs) were the most abundant followed by saturated fatty acids (SFAs) and monounsaturated fatty acids (MUFAs). On the other hand, the three seaweeds are a rich source of K (from 3781.35 to 9316.28 mg/100 g), Mn (from 8.28 to 1.96 mg/100 g), Na (from 1836.82 to 4575.71 mg/100 g) and Ca (from 984.73 to 1160.27 mg/100 g). Finally, the most abundant amino acid was glutamic acid (1874.47-1504.53 mg/100 dry matter), followed by aspartic acid (1677.01-800.84 mg/100 g dry matter) and alanine (985.40-655.73 mg/100 g dry matter).

Influence of type of muscles on nutritional value of foal meat

The effect of type of muscle on nutritional characteristic (fatty acid profile, amino acid content, cholesterol and major and minor mineral) of foal meat was investigated. Six muscles: longissimus dorsi (LD), semimembranosus (SM), semitendinosus (ST), biceps femoris (BF), triceps brachii (TB) and psoas major & minor (PM) from twelve foals slaughtered at 15 months from an extensive production system in freedom regimen were extracted for this study. Horse meat is characterized by low fat, low cholesterol content, rich in iron and in vitamin B. Statistical analysis showed that the cholesterol content did not show significant differences (P>0.05) among muscle with mean value range between 0.62 and 0.57 mg/100g. Most fatty acid presented significant differences (P<0.05) with respect to the type of muscle. The obtained results showed that except for the polyunsaturated linoleic acid, the highest contents of fatty acids were found in the hindquarter muscles. Regarding amino acid profile, significant differences (P<0.05) were observed among muscles and our results indicated that, 100g of foal meat covered from 80.6 to 86.7% for the daily requirement for an adult man weighing 70 kg for essential amino acids for ST and LD muscles, respectively. Statistical analysis showed significant differences (P=0.050) for the EAA (essential amino acids) index, which was highest for TB muscle, followed by BF and SM muscles, while the lowest values were reported by ST muscle. Finally, foal meat seems to be a very good nutritional source of major and minor minerals. The higher nutritional value of foal meat will be of great importance in the promotion of this meat.

Comparison of growth performance, carcass components, and meat quality between Mos rooster (Galician indigenous breed) and Sasso T-44 line slaughtered at 10 months

The aim of this research was to make a full study of the meat from Mos-breed roosters (Spanish indigenous chicken). To achieve this purpose, the type of breed (Mos vs. a hybrid line, Sasso T-44) and the effect of finishing treatment in the last month (corn vs. commercial fodder) on growth performance, carcass and meat quality (physicochemical and textural traits), fatty and amino acid profile, and sensorial description were studied. The finishing feeding effect did not modify the growth, but the differences between genotypes were statistically significant (P < 0.05), in where Sasso T-44 was the genotype that generated the best growths and associated parameters. With regard to carcass characteristics, no significant influences of finishing feeding treatment (P > 0.05) were found, and carcass weight clearly differed between genotypes due to the lower growth rate of Mos roosters. Drumstick, thigh, and wing percentages were greater in Mos breed than in Sasso T-44 birds, whereas breast (15.2%), that is the most highly valued piece of the chicken, was similar for both genotypes. Significant differences in pH, protein, and ash content between genotypes have been found, whereas finishing feeding treatment had an effect on myoglobin and redness index (P < 0.01), showing meat from roosters fed with corn had a higher luminosity. Despite the fact of the slaughtered age of birds, values of shear force were slightly higher than 2 kg (2.11 kg) for both genotypes, thus it can be classified as very tender meat. Mos breed showed a higher percentage of polyunsaturated fatty acids (25.90 vs. 22.74; P < 0.001) and a lower percentage of monounsaturated fatty acids (35.14 vs. 38.95; P < 0.001) than Sasso T-44 chicken muscles. Surprisingly, birds finishing with the corn diet (2 times higher in linolenic acid than fodder) did not increase their polyunsaturated fatty acid level in the breast, obtaining in the Mos breed a polyunsaturated to saturated fatty acid ratio of 0.69. The amino acid profile of the indigenous-breed breast was not similar to that of the commercial-strain breast; besides, finishing feeding treatment had more of an effect on amino acid profile, affecting the majority of amino acids, with the exception of phenylalanine and threonine.

Breed effect between Mos rooster (Galician indigenous breed) and Sasso T-44 line and finishing feed effect of commercial fodder or corn

The aim of this research was to study the Mos rooster breed growth performance, carcass, and meat quality. The breed effect (Mos vs. Sasso T-44) and finishing feed in the last month (fodder vs. corn) on animal growth, carcass characteristics, meat quality, and fatty and amino acid profiles were studied using a randomized block design with initial weight as covariance. In total, 80 roosters (n = 30 of Sasso T-44 line and n = 50 of Mos breed) were used. They were separated by breed and allocated to 2 feeding treatment groups (concentrate and corn). Each feeding treatment group consisted of 15 and 25 roosters, for Sasso T-44 line and Mos breed, respectively. Finishing feeding did not affect growth parameters in the 2 genotypes of rooster tested (P > 0.05). Nonetheless, the comparison between both types of roosters led to significant differences in growth parameters (P < 0.05). Regarding carcass characteristics, no significant influences of finishing feeding treatment (P > 0.05) were found, and as expected, carcass weight clearly differed between genotypes due to the lower growth rate of Mos roosters. However, drumstick, thigh, and wing percentages were greater in the Mos breed than in the hybrid line. In color instrumental traits, roosters feeding with corn showed breast meat with significantly (P < 0.001) higher a* and b* values than those of cocks feeding with commercial fodder. Values of shear force were less than 2 kg for both genotypes, thus it can be classified as very tender meat. Finishing with corn significantly increased (P < 0.001) the polyunsaturated fatty acid content in the breast; the Mos breed had a polyunsaturated to saturated fatty acid ratio of 0.73. The amino acid profile of the indigenous breed was not similar to that of the commercial strain. Finishing feeding treatment had a greater influence than breed effect on amino acid profile.