Effect of vegetable oils on the thermal gel properties of PSE-like chicken breast meat protein isolate-based emulsion gels.

To enhance the gel properties of PSE (pale, soft, and exudative)-like chicken meat protein isolate (PPI), the effect of peanut, corn, soybean, and sunflower oils on the gel properties of PPI emulsion gels was investigated. Vegetable oils improved emulsion stability and gel strength and enhanced viscosity and elasticity. The gel strength of the PPI-sunflower oil emulsion gel increased by 163.30 %. The thermal denaturation temperature and enthalpy values were increased. They decreased the particle size of PPI emulsion (P < 0.05) and changed the three-dimensional network structure of PPI emulsion gels from reticular to sheet with a smooth surface and pore-reduced lamellar. They elevated the content of immobile water PPI emulsion gels, decreased the α-helix and ß-turn, and increased the ß-sheet and random coil. Vegetable oil improved the gel properties of PPI in the following order: sunflower oil > soybean oil > corn oil ≈ peanut oil > control group.

Protein extracted from Moringa oleifera Lam. Leaves: Bio-evaluation and characterization as suitable plant-based meat-protein alternative.

This study aimed to isolate and characterize moringa leaf protein (MLP) via HPLC and evaluate its consumption's effects through rat model. Four groups of Albino Wistar rats (n = 25 each) along with a control group (n = 25) were acclimatized. The isolated MLP was added to the basal diet (casein; control) in various percentages (25, 50, 75, 100%) for a 21-day experimental period. On three intervals (1st, 11th, 21st days), blood samples were collected and subjected for hematological and biochemical examination (Renal Function Test (RFT), Liver Function Test (LFT)). MLP contained a variety of essential and non-essential amino acids in substantial amounts. The Protein Efficiency Ratio (PER) of 50% MLP-treated group was the highest (1.72) among MLP treatments. Increases in feed intake and weight were observed in treated rats compared to the control. The hematological profile of the rats revealed increases in Hemoglobin (Hb) (7.9-14.0%), White Blood Cell (WBC) (35.9-51.5%), Red Blood Cell (RBC) (17.1-22.2%), Hematocrit (HCT) (13.1-22.9%), and platelets levels (36.5-40.6%) from day 1. Protein isolates decreased liver parameters but resulted in non-significant changes in liver and kidney functions in rats. Further investigation is needed to determine the safe daily intake of MLP.

Carrageenan impact on digestive proteolysis of meat proteins in meatballs or soluble hydrolyzed collagen.

In a health-conscious age, vivid discussion has been made on the healthfulness of processed foods and food additives. This study focuses on carrageenan (CGN), an approved but debated family of sulphated galactans from algae used as gelling, thickening and stabilizing agents but with indications of possible adverse effects, including as an inhibitor of digestive proteolysis. To challenge this inhibitory hypothesis, food-grade kappa-, iota and lambda-CGN preparations were used to produce beef meatballs whose proteolysis was studied using an in vitro digestion model coupled to various proteomic analyses. Results show that CGN anti-nutritional effects are abolished in beef meatballs. Specifically, proteomic analysis of gastric digesta of myosin light chain 1 (MYL1), alpha skeletal muscle (ACTA1), glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and fructose-bisphosphate aldolase (ALDOA) reveal no appreciable differences in the profiles of bioaccessible peptides. Separate digestions of a soluble collagen hydrolysate show CGN does inhibit proteolysis of soluble collagen, therefore supporting the notion that the meat matrix confers a shielding effect that eliminates CGN ability to interfere with digestive proteolysis. Thus, this work shows that CGN ability to hinder digestive proteolysis may not apply to all foods and contributes evidence important to the discussions on CGN uses, indications and regulatory status.

Use of basic amino acids to improve gel properties of PSE-like chicken meat proteins isolated via ultrasound-assisted alkaline extraction.

To improve the gel quality of pale, soft, and exudative (PSE)-like chicken protein isolate (PPI) obtained via ultrasound-assisted alkaline extraction (UAE), l-lysine (l-Lys), l-arginine (l-Arg), or l-histidine (l-His) were used and the effects on the thermal gelling characteristics of PPI were studied. Compared with the nonbasic amino acid addition group, the addition of l-His/l-Arg/l-Lys significantly increased the solubility and absolute zeta potential of PPI, whereas reduced the particle size and turbidity (p < 0.05). They enhanced the gel strength and textural properties of PPI (p < 0.05) and reduced the cooking loss of PPI in the following order: l-Lys > l-Arg > l-His. The solubility, gel strength, and hardness of PPI with l-Lys were increased by 18.6%, 44.6%, and 57.6%, respectively, and cooking loss was decreased by 18.1%. Low-field nuclear magnetic resonance and magnetic resonance imaging revealed that basic amino acids addition decreased the water mobility in PPI gels with increasing immobile water content. Scanning electron microscopy revealed that the addition of basic amino acids promoted the formation of a more uniform and tight network microstructure in PPI gels. The α-helix content was decreased, whereas the ß-sheet content was increased in PPI gels after basic amino acid addition. Therefore, addition of basic amino acids, especially l-Lys, enhances the gel properties of PPI. PRACTICAL APPLICATION: This study revealed that adding basic amino acids effectively improved the gel properties of PPI obtained via UAE method, with l-Lys exerting the best improvement effect. Our findings highlight the application value of PSE-like meat by the improvement of gel characteristics of PPI, providing a theoretical reference for the processing and utilization of PPI.

Joint Association of Dietary Protein Intake and Eating Habits with the Risk of Gestational Diabetes Mellitus: A Case-Control Study.

Because the associations between different dietary protein sources and the risks of gestational diabetes mellitus (GDM) are inconsistent, and those of eating habits with GDM have rarely been explored, we aimed to investigate the independent and joint association of major dietary protein sources and eating habits with GDM in a case-control study including 353 GDM cases and 718 controls in China. Dietary protein intake and eating habits prior to GDM diagnosis were collected through questionnaires at 24~28 gestational weeks. Multivariate logistic regression was used to evaluate the independent and joint associations of dietary protein intake and eating habits with GDM. The Anderson model was used assess if there is an additive interaction between them. Animal protein, red meat protein and dairy products protein intake were significantly and positively associated with GDM. Among the eating habits, preferences for hot food, firm food and soft food were significantly associated with higher odds of GDM. Individuals with unhealthy eating habits and high dietary protein simultaneously had the highest odds of GDM, and the ORs were 2.06 (1.25, 3.41) for the total protein, 2.97 (1.78, 4.96) for animal meat, 3.98 (2.41, 6.57) for the red meat protein and 2.82 (1.81, 4.41) for the dairy protein; the p values for the trend were all significant (p < 0.001). However, no additive interaction was detected. In conclusion, our study found that dietary protein intake and eating habits prior to GDM diagnosis were both independently and jointly associated with the odds of GDM.

Current and future technologies for monitoring cultured meat: A review.

The high population growth rate, massive animal food consumption, fast economic progress, and limited food resources could lead to a food crisis in the future. There is a huge requirement for dietary proteins including cultured meat is being progressed to fulfill the need for meat-derived proteins in the diet. However, production of cultured meat requires monitoring numerous bioprocess parameters. This review presents a comprehensive overview of various widely adopted techniques (optical, spectroscopic, electrochemical, capacitive, FETs, resistive, microscopy, and ultrasound) for monitoring physical, chemical, and biological parameters that can improve the bioprocess control in cultured meat. The methods, operating principle, merits/demerits, and the main open challenges are reviewed with the aim to support the readers in advancing knowledge on novel sensing systems for cultured meat applications.

In-depth insight into the effects of tapioca or corn acetylated distarch phosphate on the gel properties and in vitro digestibility of kung-wan.

Modified starch is increasingly applied in the meat industry as an effective functional ingredient to provide meat products with the desired textural properties and appearance. This study aimed to investigate the effects of incorporating tapioca acetylated distarch phosphate (TADSP) or corn acetylated distarch phosphate (CADSP) on the gel properties and in vitro digestibility of Chinese-style meatballs known as kung-wan. The results showed that TADSP and CADSP significantly enhanced the textural properties of kung-wan in a dose-dependent manner (P < 0.05), as well as enhanced the rheological behavior of meat batters. TADSP resulted in a denser meat protein gel network compared to CADSP, primarily because the lower pasting temperature of TADSP made it gelatinize earlier and more completely during heating than CADSP and subsequently filled in the meat protein gel network. The intermolecular forces observed in kung-wan with TADSP or CADSP were hydrogen bonds and hydrophobic interactions. Furthermore, the protein digestibility of kung-wan was increased with higher levels of TADSP and CADSP (P < 0.05). Notably, kung-wan with TADSP exhibited significantly higher protein digestibility than those with CADSP at the same level (P < 0.05). Our results offer valuable insights into the potential application of acetylated distarch phosphate in kung-wan.

A review on bioactive peptides derived from meat and by-products: Extraction methods, biological activities, applications and limitations.

Meat and its by-products offer a rich source of bioactive compounds which have potential applications in both the food and pharmaceutical industries. In this review, we present several extraction methods and report the identification and properties of bioactive peptides. We also examine the challenges and limitations associated with their use in food applications. Enzymatic hydrolysis and fermentation using starts cultures are common methods for generating bioactive peptides from meat proteins. Additionally, natural gastrointestinal digestion can also produce bioactive peptides. However, emerging technologies like high hydrostatic pressure, subcritical extraction and pulsed electric fields can improve hydrolysis and increase the yield of bioactive peptides. Online bioinformatics applications have emerged as an established method for identifying potentially bioactive peptides. These tools reduce the cost and time required for traditional methods of research. Finally, incorporating bioactive peptides into diets for specific purposes such as supporting vulnerable populations like children and the elderly ensures safety and efficacy.

Using nanocellulose to improve heat-induced cull cow meat myofibrillar protein gels: effects of particle morphology and content.

BACKGROUND: Enhancing protein gel properties is essential to improve the texture of meat products. In this study, the improvement effects of three types of nanocellulose, i.e. rod-like cellulose nanocrystals (CNC), long-chain cellulose nanofibers (CNF) and spherical cellulose nanospheres (CNS) with different concentrations (1, 3, 5, 10, 15 and 20 g kg-1 ), on cull cow meat myofibrillar protein (MP) gel were investigated. RESULTS: Compared with needle-shaped CNC and spherical CNS, the addition of 10 and 20 g kg-1 long-chain CNF had the most significant improvement effect on gel hardness and water-holding capacity, respectively (P < 0.05), increasing to 160.1 g and 97.8%, respectively. In addition, the incorporation of long-chain CNF shortened the T2 relaxation time and induced the formation of the densest network structure and promoted the phase transition of the gel. However, excessive filling of nanocellulose would destroy the structure of the gel, which was not conducive to the improvement of gel properties. Fourier transform infrared results showed that there was no chemical reaction between the three nanocellulose types and MP, but the addition of nanocellulose was conducive to gel formation. CONCLUSION: The improvement of MP gel properties by adding nanocellulose mainly depends on its morphology and concentration. Nanocellulose with higher aspect ratio is more beneficial to the improvement of gel properties. For each nanocellulose type, there is an optimal addition amount for MP gel improvement. © 2023 Society of Chemical Industry.

Influence of hydrophilic polysaccharide fat replacers on the in vitro digestibility of protein in emulsion-type sausage.

Hydrophilic polysaccharides have been widely applied as fat replacers in meat products, but their effects on the digestibility of meat proteins has seldom been studied. Replacement of backfat in emulsion-type sausage with konjac gum (KG), sodium alginate (SA) and xanthan gum (XG) were found to reduce the released amino group (-NH2) during simulated gastric digestion and initial intestinal digestion. The suppressed gastric digestibility of protein was verified by the denser structures of protein gastric digests and reduced generation of peptides in gastric digestion when a polysaccharide was added. After the whole gastrointestinal digestion, high level of SA and XG resulted in larger digests and a more obvious SDS-PAGE band between 5 and 15 kDa, and KG and SA significantly reduced the total release of -NH2. Additional of KG, SA and XG were found to the increase the viscosity of the gastric digests mixture, which could account for the reduced hydrolysis efficiency of pepsin during the gastric digestion, as evidenced in the pepsin activity study (decreased by 12.2-39.1%). This work highlights the influence of polysaccharide fat replacer on the digestibility of meat protein by changing the matrix characteristics.

Investigation of the effects and mechanism of incorporation of cross-linked/acetylated tapioca starches on the gel properties and in vitro digestibility of kung-wan.

The effects and mechanism of incorporation of cross-linked tapioca starch (CTS) or acetylated tapioca starch (ATS) on the gel properties and in vitro digestibility of kung-wan (a Chinese-style meatball) were evaluated. The results indicated that incorporation of either CTS or ATS significantly enhanced the gel properties of kung-wan in a dose-dependent manner (P < 0.05), as well as the rheological properties of meat batter. Moreover, hydrogen bonds and electrostatic interaction were the major intermolecular forces in kung-wan when incorporated with CTS or ATS. Meanwhile, CTS and ATS acted as fillers in the meat protein gel matrix, which was further verified by the microstructure of kung-wan. However, CTS produced a more uniform and dense meat protein gel network than ATS, which was mainly due to its limited swelling characteristics. In addition, the incorporation of CTS or ATS significantly increased the in vitro digestibility of protein in kung-wan with increasing level of addition (P < 0.05). However, no significant differences in protein digestibility were detected between the CTS and ATS groups at the same addition level (P > 0.05). Our results provided some critical points for the actual application of modified tapioca starch to promote the quality profiles of kung-wan.

Increased Dietary Intakes of Total Protein, Animal Protein and White Meat Protein Were Associated with Reduced Bone Loss-A Prospective Analysis Based on Guangzhou Health and Nutrition Cohort, South China.

In this study, we aimed to prospectively investigate the relationships between different types of dietary protein and changes in bone mass in Chinese middle-aged and elderly people. Dietary intakes were evaluated by means of a validated food frequency questionnaire. Bone mineral density (BMD) was measured using a dual-energy bone densitometer at multiple bone sites. Multivariable regression models were applied to investigate the associations of the participants' dietary intakes of total protein, intakes of protein from various sources, and amino acid intakes with the annualized changes in BMD during a 3-year follow-up. A total of 1987 participants aged 60.3 ± 4.9 years were included in the analyses. Multivariable linear regression results showed that dietary intakes of total protein, animal protein, and protein from white meat were positively correlated with BMD changes, with standardized coefficients (ß) of 0.104, 0.073, and 0.074 at the femur neck (p < 0.01) and 0.118, 0.067, and 0.067 at the trochanter (p < 0.01), respectively. With each increase of 0.1g·kg-1·d-1 in animal protein and white meat protein intakes, the BMD losses were reduced by 5.40 and 9.24 mg/cm2 at the femur neck (p < 0.05) and 1.11 and 1.84 mg/cm2 at the trochanter (p < 0.01), respectively. Our prospective data, obtained from Chinese adults, showed that dietary total and animal protein, especially protein from white meat, could significantly reduce bone loss at the femur neck and trochanter.

The effect of the purslane polyphenols on the structure of rabbit meat myofibrillar protein under malondialdehyde-induced oxidative stress.

The present research aimed to assess the protective effects of purslane polyphenols on rabbit meat myofibrillar protein (MP) under malondialdehyde (MDA)-induced oxidation. The major polyphenols in purslane extract were analyzed by ultrahigh performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS). To analyze the protective mechanism of purslane polyphenol monomers on MP in the oxidation system, we determined the retained MDA content in the suspension and analyzed the structure and nuclear magnetic resonance (NMR) of MP. The UPLC-QTOF-MS identification analysis indicated that purslane polyphenols mainly contained chlorogenic acid, caffeic acid, ferulic acid, rutin, kaempferol, and quercetin. Polyphenols in purslane can prevent MDA from binding to MP effectively. Chlorogenic acid showed the best inhibitory effect, and the retention content of MDA decreased to 54.79%, which was significantly lower than those of other groups. Purslane polyphenols had protective effects on sulfhydryl groups, free amino groups, intrinsic tryptophan fluorescence, α-helix structure, and morphology of MP. Moreover, the carbonyl contents, increase in surface hydrophobicity, and random coil contents of MP were reduced. In addition, the NMR results indicated that polyphenols inhibited the oxidation of protein induced by MDA through competitive inhibition. PRACTICAL APPLICATION: This study showed the efficiency of purslane polyphenol monomers in protecting the structure and function of myofibrillar protein under malondialdehyde-induced oxidative stress and their potential to preserve the nutritional value of foods rich in proteins and lipids.

Comparison of the effect of Saccharomyces cerevisiae-Megasphaera elsdenii and buffer on growth performance, digestibility, ruminal histomorphometry, and carcass characteristics of fattening lambs in high concentrate diet.

This study aimed to investigate the effect of rumen pH-adjusting additives in the high-concentrated diet on functional traits, nutrient digestion, some meat parameters, and histomorphometry, and rumen histopathology. Twenty-four Arabia male lambs with 3 to 4 months old and initial body weight of 23.9 ± 3.15 kg were used in a completely randomized design with three treatments and eight replicates. The study was 77 days, including 14 days of the adaptation period and 63 days of the record taking and sampling period. The experimental treatments consisted of a control diet, control diet + sodium bicarbonate buffer, control diet + Megasphaera elsdenii, and Saccharomyces cerevisiae (bacterial-yeast). Rumen fluid was taken by stomach tube at 3 h after morning feeding to measure pH. The lambs were weighed every 3 weeks during the period, and the body weight changes, average daily gain, and total weight gain were measured, and the feed conversion ratio was calculated. At the end of the experiment, the lambs were slaughtered, and the longissimus dorsi muscle was prepared to determine the meat parameters. For histological studies, the abdominal rumen sac was sampled. There were no differences among treatments in dry matter intake (DMI), daily weight gain (ADG), and feed conversion ratio (P > 0.05). Propionate concentration was higher in the bacteria-yeast treatment than other treatments (P < 0.05). Protein digestibility was higher in control and bacteria-yeast treatments than buffer treatment (P < 0.05). The percentage of meat protein, carcass weight, and dressing percentage in bacterial-yeast treatment was higher than other treatments (P < 0.05). Rumen wall thickness in the buffer and bacterial-yeast receiving treatments was greater than the control treatment and was significant in the buffer treatment compared to the control treatment (P < 0.05). The thickness of rumen epithelial tissue in the buffer and bacterial-yeast recipient treatments was less than the control treatment (P < 0.05). Rumen papillae thickness was higher in the control treatment than other treatments (P < 0.05). Hydropic degeneration and parakeratosis were less in pH-regulating treatments than in control. The results showed that the use of Megasphaera elsdenii could be an effective way to modulate the ruminal fermentation conditions of lambs fed with high concentrate diets. In addition, to increaseing dressing percentage and meat protein, it can also reduce tissue damage and improve ruminal tissue structure.

Molecular Changes of Meat Proteins During Processing and Their Impact on Quality and Nutritional Values.

Meats are rich in lipids and proteins, exposing them to rapid oxidative changes. Proteins are essential to the human diet, and changes in the structure and functional attributes can greatly influence the quality and nutritional value of meats. In this article, we review the molecular changes of proteins during processing, their impact on the nutritional value of fresh and processed meat, the digestibility and bioavailability of meat proteins, the risks associated with high meat intake, and the preventive strategies employed to mitigate these risks. This information provides new research directions to reduce or prevent oxidative processes that influence the quality and nutritional values of meat.

Conformation changes and emulsifying properties of myofibrillar proteins in water: Effects of electrostatic interaction with chitosan.

Great interests have been attracted toward muscle protein in a water-soluble state with improved functionality for further designing meat protein fortified low-salt functional foods. In the present study, electrostatic interaction of chitosan (CH) with myofibrillar proteins (MP) in water aqueous solution was investigated, and the linked structure changes and emulsion stabilization of MP were studied. Results showed that the electrostatic interaction inhibited MP aggregation, and smaller particle size complexes were formed at pH 6.0, leading to the loss of ß-sheet contents and recovery of α-helix contents with decreasing MP/CH mixing ratio (5:1 and 1:1). The tertiary structure confirmed the conformation changes of MP in which more hydrophobic groups and active sulfhydryl groups were exposed (P < 0.05), and the fluorescence was also quenched. With decreasing mixing ratio, the droplet size of emulsion decreased (P < 0.05), while the absorbed protein content increased (P < 0.05). After 7 d of storage, complex at a ratio of 1:1 displayed desirable emulsion stability, which could be due to the improved emulsifying capacity, enhanced electrostatic repulsion and steric effects. These findings provide a better understanding of conformation changes of MP in water aqueous solution induced by electrostatic interactions at mild acidic pH and help to fabricate stable protein/polysaccharide emulsification systems for further developing meat protein-based functional food to deliver health.

Unlocking the bioactivity of meat proteins: Comparison of meat and meat hydrolysate via simulated gastrointestinal digestion.

Understanding the functional attributes of meat proteins is crucial for determining their nutritional benefits. Depending on the form in which meat proteins are available, the digestive process can release peptides which are valuable for nutrition and may also possess bioactive properties, affecting physiology. Liquid chromatography - mass spectrometry (LC-MS) was used to quantitatively compare the molecular peptide features (representing non-redundant peptides), during the different stages of a simulated gastrointestinal digestion process of a minimally processed powdered meat and its enzymatically produced hydrolysate. Results from a principal component analysis (PCA) indicated that the hydrolysate did not undergo extensive additional digestion whereas the powdered meat was digested both at the gastric and in the intestinal phases. Bioactive peptide sequence prediction identified the meat hydrolysate but not the meat powder as the only source of exact and partial bioactive matches in the angiotensin-I converting enzyme and dipeptidyl peptidase IV inhibition categories. Also, a higher source of cryptides (encrypted bioactive peptides), indicated that meat hydrolysates are potentially a better substrate for the release of these enzyme inhibitory peptides. These observations thus suggest that pre-digestion of a complex food matrix such as meat, may enhance its bioavailability following oral consumption early in the digestion process. SIGNIFICANCE: This work highlights enzymatic hydrolysis of meat proteins prior to ingestion allows for potentially higher bioavailability of bioactive peptides that inhibit angiotensin-I converting enzyme and dipeptidyl peptidase IV, thus possibly aiding high blood pressure and type 2 diabetes management.