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Black cumin (Nigella sativa L.) is well known for its strong, hot, peppery taste and has many nutritional, pharmaceutical and traditional therapeutic uses. The aim of this study was to investigate the antioxidant effect of different solvent extracts of black cumin seed to retard lipid and protein oxidation in raw ground pork meat during refrigerated storage (4 ± 1°C) for nine days.

Black cumin extracts (BCEs) were prepared using different solvents, namely, ethanol, water, ethanol:water (60:40) and methanol:hot water (60:40). Extracts were analysed for total phenolic content (TPC), 1,1 diphenyl-2-picrylhydrazil (DPPH) radical scavenging activity and reducing power. Based on the results, water extract (WE) and ethanol–water extract (EHWE) of black cumin were selected and incorporated at 1.5 per cent into freshly minced pork meat and compared with a synthetic antioxidant, butylated hydroxytoluene (BHT; 100 ppm), in retarding lipid and protein oxidation. Treated and control samples were aerobically packed in low-density polyethylene bags for analysis of various parameters (pH, colour and odour score, peroxide, lipid and protein oxidation) during nine-day refrigerated storage study.

Results showed that BCEs had a good amount of TPC (4.4-7.4 mg gallic acid equivalents/g) and also DPPH scavenging activities (33.96-44.23 per cent), with WE and EHWE extracts showing highest reducing power and promising antioxidant capacity. Hence, BCEs (WE and EHWE) incorporated at 1.5 per cent into freshly minced pork meat was tested, compared to BHT (100 ppm) and control samples, in retarding lipid and protein oxidation during storage. In BCE-treated samples, thiobarbituric acid reacting substances, free fatty acids, peroxide, formation of protein carbonyls and off-odour or rancid odour development were lower than control and values were comparable with BHT. Incorporation of BCE did not negatively affect the colour of ground pork.

BCEs (WE and EHWE) at 1.5 per cent inhibited protein and lipid oxidation and it could be exploited commercially as an effective alternative in retarding oxidative deterioration of meat products.

This study aims to investigate the influence of soy protein isolate hydrolysates (SPIH) obtained using 4 h hydrolysis under 200 MPa on proximate composition, cooking loss, textural properties, color, water distribution, microstructure, thiobarbituric acid reactive substance (TBARS) value and carbonyl and sulfhydryl contents of emulsion sausages.

Sausages with SPIHs at four concentrations (0, 1.0, 2.0 and 3.0%) were prepared, and the sausage with 0.01% butylated hydroxyanisole (BHA) was used as a positive control. Some sausages were selected for the analyses of quality characteristics and microcosmic properties. Other sausages were stored under 4 °C for 0, 7, 14, 21 and 28 days to investigate the oxidative stability.

The addition of SPIHs at various levels (0–3.0%) or 0.01% BHA did not affect the proximate composition (protein, fat and ash) of emulsion sausages. The addition of 2.0% SPIH decreased cooking loss and increased moisture content, hardness, springiness, chewiness, resilience and L* value, compared to the sausages without SPIH and with 0.01% BHA (p < 0.05). Furthermore, low-field nuclear magnetic resonance results suggested that sausages with 2.0% SPIH had the shortest T2 relaxation time. In addition, 2.0% SPIH and 0.01% BHA could inhibit the oxidation of emulsion sausages when compared with the sample without SPIH (p < 0.05). Moreover, there were no differences between sausages with 2.0% SPIH and 0.01% BHA (p > 0.05).

These findings confirmed that the 2.0% SPIH obtained under 200 MPa can be used as a natural additive to improve quality properties and antioxidant potential of emulsion sausages during storage.

The purpose of this paper is to compare the effects of repeatedly heated coconut oil, mustard oil and sunflower oil on antioxidant status in cholesterol-fed Sprague Dawley rats.

The test oils were heated at 210 ± 10°C for 15 h. Male Sprague Dawley rats were divided into six groups of six animals each. In total, 15% fresh/heated oils and 1% cholesterol were mixed with the experimental diet and fed to the animals for 60 days.

Chemical analysis revealed that repeated heating of oils resulted in changes in fatty acid composition and elevated lipid peroxidation, the effects being lower in heated coconut oil. Body weight gain significantly decreased in heated coconut oil (p = 0.02), heated mustard oil (p = 0.022) and heated sunflower oil (p = 0.001) fed animals. Malondialdehyde level was significantly increased (p = 0.001) in tissues of heated oils fed animals. Concentration of protein oxidation products was significantly increased (p = 0.001) in heated oils fed animals. Activities of antioxidant enzymes were decreased (p = 0.001) in heated oils fed animals. Total thiols were decreased (p = 0.001) in tissues of animals that were fed heated oils. Animals that were fed heated mustard oil and heated sunflower oil showed lower antioxidant levels and higher oxidation products when compared to those fed heated coconut oil.

Studies comparing the effects of thermally oxidized oils that vary in fatty acid composition are rare. The effects of fresh and heated oils that vary in fatty acid constitution, namely, coconut oil, mustard oil and sunflower oil, in cholesterol-fed rats are studied.

The purpose of this study is to investigate the effect of olive cake (OC) on oxidant/antioxidant biomarkers, lipase activity and on the histological analysis of epididymal fat, in high-fat diet (HFD)-induced obese rats.

Male obese rats were divided into two groups and were fed an HFD supplemented (HFD-OC) or not (HFD) with OC for 28 days. A control group was fed a standard diet for the same experimental period.

HFD significantly increased body weight, which was reduced by OC in the HFD-OC compared to HFD (p = 0.038). Lipase activity was higher (52%; p = 0.009) in the HFD group than the control group. Administration of OC to the obese rats decreased significantly this activity (38%; p = 0.025) compared to the HFD group. Serum thiobarbituric acid-reactive substances, lipid hydroperoxide and advanced oxidation protein products levels were significantly increased in the HFD group than the control group (p = 0.032, p = 0.023 and p = 0.017, respectively). These levels were significantly reduced in HFD-OC compared to the HFD group (p = 0.030, p = 0.021 and p = 0.010, respectively). Superoxide dismutase, glutathione peroxidase and catalase activities were decreased (53%; p = 0.04), (61%; p = 0.03) and (32%; p = 0.002), in the HFD group than the control group. OC restored these activities (46%; p = 0.01), (58%; p = 0.003) and (30%; p = 0.0003) in the HFD-OC rats than the HFD rats. Consumption of the HFD resulted in adipocyte hypertrophy. Indeed, epididymal adipocyte size was significantly larger in the HFD group than the control group (p = 0.0001), whereas it was reduced in the HFD-OC compared to the HFD group (p = 0.012).

OC possesses an anti-obesity effect. This effect might be mediated by lipase inhibition, reduced oxidative stress and increased antioxidant activities. In addition, the reduction of fat accumulation in adipose tissue by OC consumption is reflected by reducing adipocyte size.

This study aims to assess the influence of partial and simultaneous substitution of fat and sodium by hydrolyzed collagen and mix of herbs (MH) in chicken hamburgers, on the physical properties and proximal composition.

Five formulations were developed: (1) HCON–without adding collagen and MH; (2) C25M25–adding 25% of collagen and 25% of MH; (3) C25M50–adding 25% of collagen and 50% of MH; (4) C50M25–adding 50% of collagen and 25% of MH and (5) C50M50–adding 50% of collagen and 50% of MH. Chicken hamburgers were analyzed by proximal composition, sodium content, collagen and color analysis. The influence of treatments on texture profile, cooking performance and lipid oxidation of chicken hamburger was also investigated.

There was reduction in lipid and sodium for modified formulations compared with the HCON. There was great influence for some parameters, such as luminosity, cooking performance and texture profile. The formulation C50M50 showed the best cooking performance when compared to the others.

The formulation adding 50% of collagen and 50% of MH showed the highest yield and water retention (WR), with the least reduction in diameter and shrinkage, as well as presenting the best indexes of the texture profile and the lowest oxidation index, being recommended as the best combination of fat and sodium replacement.

This study aimed at the addition of grape residue flours in beef meatballs to evaluate their behavior on physic-chemical and sensory properties. Furthermore, it is intended to discuss the importance of the substitution of synthetic additives with natural ones, the enhancement of consumers' diets and the prevention of inappropriate waste disposal.

The grapes' residues were collected from wine production and transformed into flour. Their proximal chemical composition and antioxidant activities were analyzed. Then, meatballs were formulated with 0 (control), 3.5 and 7% grape flours. Lipid oxidation analyzes were performed on raw and thermally processed meatballs. Triangle and ranking sensory tests were performed to assess the consumer's perception of product appearance and flavor and the consumer's preference, respectively.

Bordeaux and Trebbiano grape flours were rich in dietary fibers, composed of 44.2 and 55.6% fibers, respectively. They showed a high antioxidant activity, in which Trebbiano was high than Bordeaux. The addition of grape flours reduced the lipid oxidation of meatballs by close to 50% than the control sample. Differences in the appearance and flavor of some meatballs were identified by the panelists; however, the flavor's change did not displease them.

The grape residue is rich in phenolic compounds, natural dyes and dietary fibers. Its addition as a functional ingredient in meatballs reduces the addition of synthetic additives, adds fiber to the consumer's diet and prevents inappropriate waste disposal.

The purpose of this study was to analyze lipid oxidation and microbiological, physical, chemical and sensory attributes of dulce de leche.

Dulce de leche samples were produced from various essential oil (EOs), control (no EO), clove, cinnamon and a clove and cinnamon mixture. After manufacturing, the products were stored at 25°C for 210 days. During storage, the samples were analyzed for texture, color, protein, lipids, lipid oxidation, pH, moisture, ash and enumeration of Salmonella sp., coliforms at 45°C, Staphylococcus sp. coagulase positive and mesophilic bacteria. The sensory analysis used a hedonic scale for appearance, smell, taste and texture attributes and overall acceptance.

The addition of EOs (clove and cinnamon) did not alter (p > 0.05) the proximal composition, texture, color or sensory attributes of dulce de leche. All products presented a good acceptance rate (>70 per cent). However, among the samples containing EO, dulce de leche with cinnamon presented a higher acceptance (81.67 per cent), and after 210 days of storage, it had lower (40.9 μg malonaldehyde/g p-value <0.01) lipid oxidation. Microbiological analyses indicated that the EOs are active antimicrobial components and are viable inclusions in this type of product.

The inclusion of EOs in dulce de leche provided an overall sensory acceptance similar to the traditional product and all products, including the control, were comparable. Dulce de leche produced with EOs is marketable.

The purpose of this paper is to determine the influences of fat content and storage temperature on the quality of frozen pork patties during storage to evaluate the shelf life set by the manufacturer.

Changes in moisture content, acid value, peroxide value, thiobarbituric acid value, total volatile basic nitrogen content, and the sensory score of frozen pork patties with 10 and 15 percent fat contents during storage at −5, −15, and −23°C for six months.

Although microbiological quality remained unchanged, moisture content decreased, and lipid rancidity and protein putrefaction increased significantly during storage. More rapid deterioration in quality was observed in patties stored at −5°C than those stored at lower temperatures. Lipid rancidity and protein putrefaction increased more rapidly (but not significantly) in patties with 15 percent fat than those with 10 percent fat. Overall acceptance of the sensory properties was closely correlated with the above quality indicators, except thiobarbituric acid value. Acceptable qualities of the samples were maintained for the first two, four, and six months under storage at −5, −15, and −23°C, respectively.

The current shelf life of frozen pork patties set by manufacturers, assuming a storage temperature of −18°C, needs to be readjusted considering practical storage temperatures.

No studies have comprehensively explored the effects of fat content and storage temperatures on the quality of ground meat products during frozen storage. These approaches to determine quality changes may be useful for manufacturers to predict and control the quality of their products.

The aim of the article was to focus on various peptides identified in the egg and their probable application as novel ingredients in the development of functional food products. Bioactive peptides of egg origin have attracted increasing interest as one of the prominent candidates for development of various health-promoting functional and designer foods.

Traditionally known as a source of highly valuable proteins in human nutrition, eggs are nowadays also considered as an important source of many bioactive peptides which may find wide application in medicine and food production. These specific protein fragments from egg proteins which, above and beyond their nutritional capabilities, have a positive impact on the body’s function or condition by affecting the digestive, endocrine, cardiovascular, immune and nervous systems, and may ultimately influence health.

Several peptides that are released in vitro or in vivo from egg proteins have been attributed to different health effects, including antihypertensive effects, antimicrobial properties, antioxidant activities, anticancer activity, immunomodulating activity, antiadhesive properties and enhancement of nutrient absorption and/or bioavailability. Extensive research has been undertaken to identify and characterize these biologically active peptides of egg origin which has changed the image of egg as a new source of biologically active ingredients for the development of functional foods with specific benefits for human health and treatment and prevention of diseases.

The paper mainly describes the above-stated properties of bioactive peptides derived from egg proteins.

The purpose of this study was to isolate Whitemouth croaker protein by alkaline solubilization process and evaluate their nutritional quality to evaluate the bioavailability of essential amino acids.

The proximate composition, essential amino acid composition, in vitro digestibility, apparent bioavailability, chemical score of amino acids and SDS-PAGE were determined for the isolated croaker proteins.

The isolated protein showed a high level of protein 92.21 percent and low amount of lipids 0.57 percent. The protein is rich in lysine and leucine, 108.73 and 96.75 mg/g protein, respectively. The protein isolate had high digestibility, 94.32 percent, which indicates proper utilization of this protein source, while the tryptophan had lower bioavailability (12.58 mg amino acid/mg protein). The high chemical scores were found for the amino acids lysine, methionine+cysteine (6.79 and 5.14). SDS-PAGE of proteins extracted showed appearance of the heavy chain of myosin (220 kDa), actin (50 kDa) and other fractions, with molecular weight between 20 and 50 kDa, such as troponin I, C and T.

The products obtained from croaker muscle can be incorporated as a high value supplements in human diets. The isolated protein exhibited a high content of essential amino acids and digestibility, indicating that the protein has a high nutritional quality.