Antioxidative effect of dietary grape pomace concentrate on lipid oxidation of chilled and long-term frozen stored chicken patties

Selected fruit pomaces: Nutritional profile, health benefits, and applications in functional foods and feeds

The utmost objective of every nation is to achieve zero hunger and ensure the health and well-being of its population. However, in impoverished nations, particularly in rural areas, such issues persist on a daily basis. Currently, there is a growing demand for fruit consumption due to their potential health benefits. Surprisingly, their most prevalent by-product is pomace, which is produced in millions of tonnes and is usually discarded as waste after processing or consumption. Even food produced with these kinds of raw resources can contribute to the objective of eradicating world hunger. Owing to these advantages, scientists have begun evaluating the nutritional content of various fruit pomace varieties as well as the chemical composition in different bioactive constituents, which have significant health benefits and can be used to formulate a variety of food products with notable nutraceutical and functional potential. So, the purpose of this review is to understand the existing familiarity of nutritional and phytochemical composition of selected fruit pomaces, those derived from pineapple, orange, grape, apple, and tomato. Furthermore, this article covers pre-clinical and clinical investigations conducted on the selected fruit pomace extracts and/or powder forms and its incorporation into food products and animal feed. Adding fruit pomaces reduces the glycemic index, increases the fibre content and total polyphenolic contents, and reduces the cooking loss, etc. In animal feeds, incorporating fruit pomaces improves the antioxidant enzyme activities, humoral immune system, and growth performance and reduces methane emission.

Lipid Peroxidation in Muscle Foods: Impact on Quality, Safety and Human Health

The issue of lipid changes in muscle foods under the action of atmospheric oxygen has captured the attention of researchers for over a century. Lipid oxidative processes initiate during the slaughtering of animals and persist throughout subsequent technological processing and storage of the finished product. The oxidation of lipids in muscle foods is a phenomenon extensively deliberated in the scientific community, acknowledged as one of the pivotal factors affecting their quality, safety, and human health. This review delves into the nature of lipid oxidation in muscle foods, highlighting mechanisms of free radical initiation and the propagation of oxidative processes. Special attention is given to the natural antioxidant protective system and dietary factors influencing the stability of muscle lipids. The review traces mechanisms inhibiting oxidative processes, exploring how changes in lipid oxidative substrates, prooxidant activity, and the antioxidant protective system play a role. A critical review of the oxidative stability and safety of meat products is provided. The impact of oxidative processes on the quality of muscle foods, including flavour, aroma, taste, colour, and texture, is scrutinised. Additionally, the review monitors the effect of oxidised muscle foods on human health, particularly in relation to the autooxidation of cholesterol. Associations with coronary cardiovascular disease, brain stroke, and carcinogenesis linked to oxidative stress, and various infections are discussed. Further studies are also needed to formulate appropriate technological solutions to reduce the risk of chemical hazards caused by the initiation and development of lipid peroxidation processes in muscle foods.

Impact of grape (Vitis vinifera) seed extract on egg production traits, nutrients digestability, lipid peroxidation and fertility of golden laying hens (Gallus gallus) during early stage of production

Grape by-products represent outstanding alternatives to replace conventional and unsustainable feed sources, given the substantial quantities generated annually by the winery industry. Regrettably, the majority of these by-products are wasted, resulting in significant environmental and economic repercussions. This study was conducted to assess the growth performance, feed efficiency, egg production and quality, lipid peroxidation, fertility and hatchability of reproductive laying hens during their early production stage. A total of 720 golden laying hens, all approximately 25 weeks old and with similar body weights, were randomly assigned to four experimental treatments (six replicates) as follows: control group receiving only the standard diet, (2) a group receiving the standard diet supplemented with grape seed extract at a rate of 250 g/kg (GSE1), (3) a group receiving the standarddiet supplemented with grape seed extract at a rate of 500 g/kg (GSE2), and (4) a group receiving the standarddiet supplemented with grape seed extract at a rate of 750 g/kg (GSE3). There were no significant change (p > 0.05) in feed intak, body weight gain and feed conversion ratio between the control and the experimental groups. Egg weight, egg shell thickness and egg shell weight were significantly (p < 0.05) higher in GSE250 GSE500 and GSE750 compared to the control. The results showed that hen day egg production was also significantly higher (p < 0.05) in GSE500 and GSE 750 compared to the control. Fertility level of GSE 500 and GSE750 was significantly (p < 0.5) higher compared to the control. The MDA level decreased significantly (p < 0.05) in the GSE supplemented birds compared to the control. From these findings, we concluded that GSE 750 had positive impact on egg production, reducing lipid peroxidation and improving fertility in golden laying hens.

Grape Pomace: Agrifood By-Product with Potential to Enhance Performance, Yolk Quality, Antioxidant Capacity, and Eggshell Ultrastructure in Laying Hens

Grape pomace (GP) is an industrial by-product of grape juice making and is commonly discarded as a waste product, even with its large quantity of phytochemicals. Thus, the objectives of this trial were to examine the effects of graded dietary GP on laying rate, egg quality, yolk lipid profile, oxidative stability, shell quality and ultrastructure, and serum biochemistry. Two hundred 35-week-old laying hens were allocated to four dietary treatments with ten replicates each. Four diets were formulated by mixing a standard basal diet with GP at 0 g/kg (control), 30 g/kg (GP_3%), 60 g/kg (GP_6%), and 90 g/kg (GP_9%). Egg production percent, egg weight, and egg mass were linearly improved (p < 0.01) due to adding GP to the diets of laying hens. Eggs obtained from laying hens fed with GP diets had (p < 0.01; linear, p < 0.01) greater Haugh units, yolk color, albumen index, and yolk index than those of the control. The GP_9% group had the greatest values (p < 0.05) for shell weight, thickness, and breaking strength. Electron microscopy scanning of eggshells indicated that the incremental dietary level of GP linearly augmented the thickness of the palisade layer but reduced both the mammillary layer and mammillary knob width (p < 0.01). Improved tibia-breaking strength and ash content were shown (p < 0.05) in the GP-fed laying hens. The dietary addition of GP by up to 90 g/kg linearly (p < 0.01) mitigated lipid oxidation and improved the antioxidant capacity in both the serum and stored eggs. A reduction in the percentages of saturated fatty acids was observed, while the contents of monounsaturated fatty acids, polyunsaturated fatty acids, and n-3 fatty acids were augmented because of increasing dietary GP levels (p < 0.001). Additionally, the eggs obtained from laying hens fed on the GP_6% and GP_9% had lower yolk cholesterol content (p < 0.001); this effect was confirmed by linear and quadratic responses (p < 0.001). Laying hens on GP diets had lower (p < 0.01) serum hepatic enzymes, cholesterol, triglycerides, and low-density lipoprotein but greater high-density lipoprotein compared to the control. To sum up, the addition of GP in the layers' diets by up to 90 g/kg increased laying performance, enriched the yolk with beneficial fatty acids, enhanced antioxidant potential in yolk lipids, and improved shell quality and ultrastructure.

Effects of Plant-Based Antioxidants in Animal Diets and Meat Products: A Review

The perceived level of risk associated with a food product can influence purchase and consumption decisions. Thus, current trends in food safety address an issue of general interest-the identification of healthy and economical alternatives to synthetic antioxidants that may have harmful effects on human health. Still, the processors' target is to increase the shelf life of food products using preserving substances. Natural antioxidants can be extracted and used in the food industry from different plants, such as blueberry, broccoli, chokeberry, cinnamon, ginger, olives, oregano, etc. The identification of the main natural antioxidant types that have been used in the food industry is very important in order to provide a comprehensive analysis of the researched topic. In this regard, the aim of this paper was to illustrate the positive aspects of using natural antioxidants with preservative roles in meat products, while, at the same time, highlighting the potential risks induced by these compounds. All of those aspects are correlated with the impact of sensorial attributes and the improvement of the nutritional value of meat products.

Antioxidant, Organoleptic and Physicochemical Changes in Different Marinated Oven-Grilled Chicken Breast Meat

The antioxidant, organoleptic, and physicochemical changes in different marinated oven-grilled chicken breast meat were investigated. Specifically, the chicken breast meat samples were procured from a local retailer in Wroclaw, Poland. The antioxidant aspects involved 2,2'-azinobis-(3-ethylbenzthiazolin-6-sulfonic acid) (ABTS), 1,1-diphenyl-2-pierylhydrazy (DPPH), and ferric-reducing antioxidant power (FRAP). The organoleptic aspects involved sensory and texture aspects. The physicochemical aspects involved the pH, thiobarbituric acid reactive substance (TBARS), cooking weight loss, L* a* b* color, and textural cutting force. Different marination variants comprised incremental 0.5, 1, and 1.5% concentrations of Baikal skullcap (BS), cranberry pomace (CP), and grape pomace (GP) that depicted antioxidants, and subsequently incorporated either African spice (AS) or an industrial marinade/pickle (IM). The oven grill facility was set at a temperature of 180 °C and a constant cooking time of 5 min. Results showed various antioxidant, organoleptic and physicochemical range values across the different marinated oven-grilled chicken breast meat samples, most of which appeared somewhat limited. Incorporating either AS or IM seemingly widens the ABTS and FRAP ranges, with much less for the DPPH. Moreover, with increasing CP, GP, and BS concentrations, fluctuations seemingly persist in pH, TBARS, cooking weight loss, L* a* b* color, and textural cutting force values even when either AS or IM was incorporated, despite resemblances in some organoleptic sensory and texture profiles. Overall, the oven-grilling approach promises to moderate the antioxidant, organoleptic, and physicochemical value ranges in the different marinated chicken breast meat samples in this study.

Effect of dietary flaxseed meal supplemented with dried tomato and grape pomace on performance traits and antioxidant status of laying hens

This study was carried out to determine the effect of dietary flaxseed meal (FSM) supplemented with dried tomato pomace (DTP) and dried grape pomace (DGP) on performance, egg quality, biochemical parameters traits and antioxidant status of laying hens. Birds (1825 ± 87 g of body weight) were divided into 12 dietary groups with six replicates per group (eight birds per replicate), under a completely randomized design with factorial arrangement 2 × 3 × 2 consisted of two levels of DTP (0 and 15%), three FSM levels (0, 4 and 8%) and two levels of DGP (0 and 5%). As a result of this study, there were no significant differences in egg production and weight as well in feed conversion ratio (FCR) among treatments (p > 0.05). Feeding of DGP reduced significantly feed intake and egg mass when compared to control group (p < 0.05). There was no effect (p > 0.05) of dietary treatment on shell thickness and strength, shape index, Haugh unit and egg specific gravity. Hens consuming 15% DTP and 5% DGP revealed a significantly higher yolk color compared to the other dietary treatments (p < 0.05). Moreover, there was no difference among dietary treatments in terms of serum low-density lipoprotein cholesterol (LDL) and high-density lipoprotein cholesterol (HDL) cholesterol, atherogenic index, triglycerides, total cholesterol levels (p > 0.05). Serum antioxidant parameters as glutathione peroxidase (GSH-Px) activity, malondialdehyde (MDA), total superoxide dismutase (TSOD) and total antioxidant capacity (T-AOC) were not influenced by treatments (p > 0.05). Based on findings, FSM and DTP supplements did not significantly impact most of hens' performance indicators and egg quality parameters, whereas significant improvements were observed by feeding of 15% DTP and 5% DGP on egg traits, in particular on egg-yolk color that plays a key-role in consumer's choice. However, the supplementation of FSM and DTP or DGP even in laying hen diet is still controversial and further research is needed.

A comparative study of vacuum tumbling and immersion marination on quality, microstructure, and protein changes of Xueshan chicken

Marination is a common technology in meat processing with advantages of enhancing tenderness, water retention, and overall quality. This study was conducted to investigate the effect of vacuum tumbling and immersion marination on meat quality, microstructure, water mobility, protein changes, and denaturation of Xueshan chicken. Results showed that vacuum tumbling significantly increased the marinating rate of chicken, tenderness, meat texture, and water retention. Meanwhile, vacuum tumbling decreased total sulfhydryl content alongside an increased protein surface hydrophobicity and free sulfhydryl content, indicating that vacuum tumbling elevated the degree of protein denaturation. Further, the peak area corresponding to the relaxation time T22 after vacuum tumbling was significantly higher than that of immersion marination, suggesting that the stability of the immobilized water of chicken was reduced by vacuum tumbling. Compared to immersion marination, vacuum tumbling improved myofibril fragmentation index (MFI) presenting fewer myofibrillar protein bands in sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) gel and more damaged muscular cells. Overall, vacuum tumbling could improve the marination absorptivity, protein degradation, and denaturation, resulting in changes in myofibril structure and meat quality of Xueshan chicken.

Grape Pomace Polyphenols as a Source of Compounds for Management of Oxidative Stress and Inflammation—A Possible Alternative for Non-Steroidal Anti-Inflammatory Drugs?

Flavonoids, stilbenes, lignans, and phenolic acids, classes of polyphenols found in grape pomace (GP), were investigated as an important alternative source for active substances that could be used in the management of oxidative stress and inflammation. The benefic antioxidant and anti-inflammatory actions of GP are presented in the literature, but they are derived from a large variety of experimental in vitro and in vivo settings. In these in vitro works, the decrease in reactive oxygen species, malondialdehyde, and thiobarbituric acid reactive substances levels and the increase in glutathione levels show the antioxidant effects. The inhibition of nuclear factor kappa B and prostaglandin E2 inflammatory pathways and the decrease of some inflammatory markers such as interleukin-8 (IL-8) demonstrate the anti-inflammatory actions of GP polyphenols. The in vivo studies further confirmed the antioxidant (increase in catalase, superoxide dismutase and glutathione peroxidase levels and a stimulation of endothelial nitric oxide synthase -eNOS gene expression) and anti-inflammatory (inhibition of IL-1𝛼, IL-1β, IL-6, interferon-𝛾, TNF-α and C-reactive protein release) activities. Grape pomace as a whole extract, but also different individual polyphenols that are contained in GP can modulate the endogenous pathway responsible in reducing oxidative stress and chronic inflammation. The present review analyzed the effects of GP in oxidative stress and inflammation, suggesting that it could become a valuable therapeutic candidate capable to reduce the aforementioned pathological processes. Grape pomace extract could become an adjuvant treatment in the attempt to reduce the side effects of the classical anti-inflammatory medication like non-steroidal anti-inflammatory drugs (NSAIDs).

Fruit pomaces-their nutrient and bioactive components, effects on growth and health of poultry species, and possible optimization techniques

The ever-growing human population, coupled with the exigent need to meet the increasing demand for poultry meat and egg, has put the onus on poultry nutritionists and farmers to identify alternative feed ingredients that could assure the least-cost feed formulation. In addition, the public desire for non-antibiotic-treated poultry products has also necessitated the ultimate search for potent antibiotic alternatives for use in poultry production. While some identified alternatives are promising, their cost implications and technical know-how requirements may discourage their ease of adoption in poultry. The use of plants and/or their by-products, like fruit pomaces, present a pocket-friendly advantage and as a result, are gaining much interest. This is traceable to their rich phytochemical profile, nutritional composition, ready availability, and relatively cheap cost. The fruit juice and wine pressing industries generate a plethora of fruit wastes annually. Interestingly, fruit pomaces contain appreciable dietary fibre, protein, and phenolic compounds, and thus, their adoption could serve the poultry industry in dual capacities including as substitutes to antibiotics and some conventional feedstuff. Thus, there is a possibility to reduce fruit wastes produced and feed-cost in poultry farming from environmental and economical standpoints, respectively. This review seeks to provide reinforcing evidence on the applicability and impact of fruit pomaces in poultry nutrition.

Antioxidant Activity of Moringa oleifera and Olive Olea europaea L. Leaf Powders and Extracts on Quality and Oxidation Stability of Chicken Burgers

Oxidation is the main cause of quality deterioration in meat-based foods, such as burgers. Antioxidants inhibit the oxidation process; recently, natural antioxidants have gained interest, due to safety concerns. In this study, the effects of leaf powder and crude extracts of both Moringa oleifera and olive in chicken burgers were studied for their antioxidant potential in preventing fat oxidation during storage. Antioxidant activities were evaluated using DPPH (2,2-diphenyl-1-picrylhydrazyl). The results showed the highest DPPH radical scavenging with IC50 values of 2.397 ± 0.10 mg/mL in the Moringa leaf. Total phenolic content (TPC) was crude olive extract > crude Moringa extract > olive leaf > Moringa leaf. The total flavonoid content (TFC) was significantly higher in the olive leaf and its crude extract than in the Moringa leaf and its crude extract. The pH, total volatile nitrogen, and sensory properties were affected by the addition of olive and Moringa (leaf and crude extracts) to chicken burgers refrigerated for 20 days. The addition of Moringa and olive leaf powder decreased lipid oxidation and PV after 10 days of storage. In general, Moringa and olive leaf treatments slowed the deterioration of meat, suggesting their use as preservatives to extend the shelf-life of chicken burgers.

Dietary grape pomace - effects on growth performance, intestinal health, blood parameters, and breast muscle myopathies of broiler chickens

The search for alternatives to antibiotics in poultry production is still on-going and has been directed towards investigation of the efficacy of different potential alternatives. However, it is important that the sought alternatives are cost-efficient and have no negative impact on meat quality, for ease of adoption and profit maximization. This study aimed at exploiting an agro-industrial waste, grape pomace (GP) as an alternative to in-feed antibiotics and assessing the effects on growth, intestinal morphology, ceca microbiota, ceca short-chain fatty acid (SCFA) concentration, blood biochemical parameters, and breast muscle myopathies of broiler chickens. A total of 576 one-day-old Cobb-500 broiler chicks were randomly allotted to 3 dietary treatments - Negative control (NC, a corn-wheat soybean-based diet), NC + 0.05% bacitracin methylene disalicylate (BMD), and NC + 2.5% GP. Each treatment was assigned to 8 replicate pens with 25 birds per pen. Body weight (BW), feed intake (FI), and feed conversion ratio (FCR) were determined weekly. On d 36, 2 chickens/pen were euthanized for measuring blood biochemical parameters, ceca SCFA, and ceca microbiota. White striping (WS) and wooden breast (WB) incidence were assessed in 4 chickens/pen on d 42. The GP diet increased (P < 0.05) average FI throughout the feeding phases compared to the other treatments, but overall FCR was similar. Birds in the GP treatment had higher (P < 0.05) villus height (VH) and increased VH:crypt depth ratio in the duodenum and jejunum compared to other treatments. The level of ceca SCFA and the incidence of WS and WB was the same for all treatments. Plasma Ca and P were significantly higher (P < 0.05) in birds fed GP and BMD, compared to the NC. Birds in the GP treatment had significantly reduced (P < 0.05) plasma aspartate transaminase than other treatments. Birds receiving GP had a higher (P < 0.05) relative abundance of the phylum Bacteroidetes and reduced (P < 0.05) Firmicutes compared to other treatments. The relative abundance of Bacteroides and Lactobacillus genera were higher (P < 0.05) among birds fed GP compared to other treatments. Inclusion of 2.5% GP in broiler chicken diets improved gut morphology and modified the cecal bacterial community and blood biochemical profiles with no adverse effect on growth performance and meat quality.

Effect of Dietary Grape Pomace on Fattening Rabbit Performance, Fatty Acid Composition, and Shelf Life of Meat

The use of agroindustry by-products in animal diets allows the use of residues that are not fit for human consumption. In this study, it was investigated whether fattening commercial rabbits during 30 days with a non-medicated feed, with 20% addition of grape pomace (GPD), affected production traits and the fatty acid composition, antioxidants properties, and the shelf life of the meat compared to a conventional strategy (CON). Furthermore, it was tested, by chromatographic analysis, whether this alternative diet allowed the transfer of phenolic compounds to the meat. Thirty-six weaned rabbits were allotted to the two treatments. In each treatment, 18 rabbits were fattened in three indoor cages, each housing three males and three female rabbits. No significant differences were found in live weights (p > 0.05), but the feed conversion rate and carcass weight and yield were found to be impaired in the GPD group (p ≤ 0.05). The GPD group had a higher intramuscular fat percentage (2.01 vs. 1.54), improved polyunsaturated/saturated fatty acids ratio (0.75 vs. 0.66), and better atherogenicity (0.71 vs. 0.83) and thrombogenicity (1.14 vs. 1.24) indexes, while the n-6/n-3 ratio was higher (25.4 vs. 20.3). Total volatile basic nitrogen in meat was lower in the GPD group (p = 0.01), suggesting a delayed spoilage. However, no improvements in total phenolic content, antioxidant capacity, reducing power, and lipid oxidation (p > 0.05) were found in the meat. Even though the GPD pellets offered to the animals had several grape-derived phenolic compounds, and higher antioxidant properties compared to the CON diet, none of the phenolic compounds detected in feeds were detected in the meat samples.

Dietary Polyphenol Supplementation in Food Producing Animals: Effects on the Quality of Derived Products

Simple Summary

Polyphenols are secondary plant metabolites mainly known for their antioxidant properties. Their use as feed additives in the nutrition of farm animals is becoming increasingly popular as they are particularly exposed to oxidative stress which is reflected in a lipoperoxidation of the final product. For this reason, it is essential to preserve the quality and the safety of meat and milk products by attenuating oxidative deterioration. Moreover, polyphenols present the advantage of being more acceptable to the consumers than synthetic counterparts, as they are considered to be “non-toxic”. The present review presents an overview of several studies focused on the dietary supplementation of polyphenols to monogastric and ruminants, as well as their direct addition to meat and dairy products, with particular emphasis on their antioxidant effects on the final product.

Abstract

The growing interest in producing healthier animal products with a higher ratio of polyunsaturated to saturated fatty acids, is associated with an increase in lipoperoxidation. For this reason, it is essential to attenuate oxidative deterioration in the derived products. Natural antioxidants such as polyphenols represent a good candidate in this respect. The first part of the review highlights the occurrence, bioavailability, and the role of polyphenols in food-producing animals that, especially in intensive systems, are exposed to stressful situations in which oxidation plays a crucial role. The second part offers an overview of the effects of polyphenols either supplemented to the diet of monogastric and ruminants or added directly to meat and dairy products on the physicochemical and sensorial properties of the product. From this review emerges that polyphenols play an important, though not always clear, role in the quality of meat and meat products, milk and dairy products. It cannot be ruled out that different compounds or amounts of polyphenols may lead to different results. However, the inclusion of agro-industrial by-products rich in polyphenols, in animal feed, represents an innovative and alternative source of antioxidants as well as being useful in reducing environmental and economic impact.

Effect of Raw and Fermented Grape Pomace on the Growth Performance, Antioxidant Status, Intestinal Morphology, and Selected Bacterial Species in Broiler Chicks

The effects of raw (GP) and fermented grape pomace (FGP) on the growth performance, some carcass parameters, antioxidant status, intestinal morphology, and selected bacterial species in broiler chicken were investigated in this study. Grape pomace was fermented with Aspergillus niger for 7 d. In total, 140 one-day-old male chicks (Ross 308) were randomly assigned to four treatment groups, with five replicates and seven birds each. Chickens were fed either a basal diet (CON) or the basal diet supplemented with 0.25 g/kg synthetic antioxidants (5% butylated hydroxytoluene, 1% butylated hydroxyanisole, and 11% ethoxyquin) (AO), or 15 g/kg GP (GP), or 15 g/kg FGP (FGP) for 42 d. Dietary GP raised serum glutathione peroxidase (p = 0.031) and superoxide dismutase (p = 0.021) levels, increased ileum lamina muscularis thickness (p = 0.016), and did not affect selected bacterial species in the cecum of broiler chickens. Dietary FGP improved body weight (p = 0.003), increased the serum catalase level (p = 0.032), and decreased the cecal Clostridium perfringens count (p = 0.033) but did not affect the ileal morphology of broiler chickens. The carcass parameters, malondialdehyde level, pH, and color of the breast meat of chickens were not changed by either GP or FGP supplementation. Chickens fed with the synthetic antioxidants had similar growth performance with the chickens fed with FGP but had better body weight (p = 0.003) and feed conversion ratio (p = 0.045) compared with the chickens fed with GP. The obtained results showed that FGP can be used as an alternative to synthetic antioxidants in broiler diets.

Plant-Derived Natural Antioxidants in Meat and Meat Products

The global meat industry is constantly evolving due to changes in consumer preferences, concerns and lifestyles, as well as monetary, geographical, political, cultural and religious factors. Part of this evolution is the introduction of synthetic antioxidants to increase meat and meat products' shelf-life, and reduce meat spoilage due to lipid and protein oxidation. The public perception that natural compounds are safer and healthier per se has motivated the meat industry to replace synthetic antioxidants with plant-derived ones in meat systems. Despite several promising results from in vitro and in situ studies, the effectiveness of plant-derived antioxidants against lipid and protein oxidation has not been fully documented. Moreover, the utility, usability, marketability and potential health benefits of natural antioxidants are not yet fully proven. The present review aims to (i) describe the major chemical groups of plant-derived antioxidants and their courses of action; (ii) present the application of spices, herbs and fruits as antioxidants in meat systems; and (iii) discuss the legislative framework, future trends, challenges and limitations that are expected to shape their acceptance and mass exploitation by the meat industry.

Influence of Grape Pomace Intake on Nutritional Value, Lipid Oxidation and Volatile Profile of Poultry Meat

Grape pomace (GP) represents the main solid by-product deriving from grape processing. The aim of this study was to evaluate the effect of dietary GP intake on nutritional quality, lipid oxidation and volatile profile of chicken meat. A total of 112 Ross 508 broilers were randomly divided into 4 groups and fed for 21 days with a standard diet. For the remaining 28 days of the trial, the control group (CG) continued to receive a standard diet, while the experimental groups (EGs) were fed with diets containing different GP concentrations: 2.5% (EG1), 5% (EG2) and 7% (EG3). Following the slaughtering, samples of breast meat were collected from each group. No significant differences were observed for pH, cooking loss and meat brightness, whereas the GP intake showed effectiveness in inducing variations in drip loss, meat yellowness and redness. The experimental feeding strategy also induced changes in the fatty acid profile, with an overall increase in polyunsaturated fatty acids (PUFA), mainly due to the increase in concentration of linoleic acid. The dietary supplementation also induced a decrease in lipid oxidation in meat, a finding also confirmed by the reduction in volatile aldehydes in 7 days stored raw meat. The feeding strategy based on the use of GP did not induce detrimental effects on the quality of broiler meat and showed the potential to lengthen the shelf-life as a direct consequence of the improvement in the oxidative stability. Overall, the present study showed a viable way for the recovery and the valorization of an agro-industrial by-product, with potential benefits also from an environmental point of view.

Lipid and color stability of the meat and sausages of broiler fed with calcium anacardate

BACKGROUND

Anacardic acid, a phenolic compound, represents 90% of cashew nut shell liquid, which is a byproduct from the industrial processing of cashew nuts. This study aimed to add calcium anacardate (CA) to broilers' diets as a source of anacardic acid, to evaluate its antioxidant effect in breast meat and in processed meat products (sausages). For this purpose, birds were fed according to the following treatments: diet without antioxidant and diets containing 2.5, 5.0, 7.5, or 10.0 g kg^-1 CA. Chicken breast meat was stored frozen for 90 days. The thigh and drumsticks were used to produce chicken sausages that were kept in refrigerated conditions for 90 days. Lipid oxidation and color stability were assessed every 30 days.

RESULTS

For breast meat, a 2.5 g kg^-1 concentration of CA was insufficient to retard lipid oxidation, whereas 10.0 g kg^-1 gave rise to a pro-oxidant effect and 5.0 g kg^-1 slowed the oxidation up to 50 days. A level of 7.5 g kg^-1 of CA was effective in retarding oxidation, favoring colour stability during the 90-days frozen storage. For sausages, 2.5 g kg^-1 of calcium anacardate in broiler diets was sufficient to retard lipid oxidation. Calcium anacardate 7.5 g kg^-1 provided greater redness in the sausages compared with the control and with the other treatments containing 5.0 and 10.0 g kg^-1 .

CONCLUSIONS

Calcium anacardate is a potential natural antioxidant for breast meat and sausages in storage when added to broilers' diets. © 2018 Society of Chemical Industry.

Grape by-product extracts against microbial proliferation and lipid oxidation: a review

The wine industry is responsible for the production of million tons of waste, such as grape skin, stalk, sludge and seeds, which can be considered inexpensive sources of phenolic compound owing to incomplete extraction during wine production. Phenolic compounds, also called polyphenols, comprise the most abundant bioactive compounds in grape and are recognized by their antioxidant and antimicrobial potential. Because of their functional properties, extracts obtained from grape wastes, which are rich in phenolic compounds, can be employed in the development of many products, ranging from medical to food applications, decreasing the growth of spoilage and pathogenic microorganisms and inhibiting lipid oxidation. These characteristics are motivating the research for alternative sources of natural antioxidant and antimicrobial agents, aimed at decreasing the use of artificial additives, which have been associated with some toxic effects. This article provides a review of the use of grape by-product extracts and their bioactive compounds as natural antioxidant and antimicrobial agents in food products. © 2016 Society of Chemical Industry.

Addition of exogenous enzymes to diets containing grape pomace: Effects on intestinal utilization of catechins and antioxidant status of chickens

Grape pomace (GP) is a rich source of polyphenols with antioxidant capacity. An experiment was conducted to study the effect of GP phenolic compounds included at 5 and 10%, and the addition (individually or combined) of hydrolyzing enzymes (carbohydrase enzyme complex and tannase at 500ppm) on intestinal utilization of catechins and antioxidant status in broiler chickens. A diet supplemented with 200ppm of α-tocopheryl acetate was also used. Our findings demonstrate the capacity of chickens to digest the monomeric (catechin, epicatechin, gallic acid, and epicatechin-O-gallate) and dimeric (procyanidin B1 and procyanidin B2) catechins present in grape pomace. The addition of enzymes (mainly tannase) hydrolyzed the polymeric structures into smaller catechins, but also promoted a lower digestibility of the monomeric and dimeric catechins suggesting that polymeric structures might favour the intestinal utilization of these catechins. The intestinal accumulation of phenolic compounds generated with tannase and with 10% GP reversed the antimicrobial effect against Clostridium perfringens observed with 5% of GP. Grape pomace improved the antioxidant status of the bird, increasing the α-tocopherol and reducing the iron content on plasma, not affecting the plasma gluthatione. Enzymes modified the intestinal utilization of catechins but not additional protective effect was detected on any of the parameters analyzed to evaluate the antioxidant status.

Evaluation of the joint effect of the incorporation of mechanically deboned meat and grape extract on the formulation of chicken nuggets

The proximate composition, instrumental and perceived appearance of chicken nuggets formulated with varying contents of mechanically deboned chicken meat and varying concentrations of grape pomace extract were evaluated, with the choice of formulations following a central composite design. Significant differences (P < 0.05) in fat content were mainly associated to the extent of mechanically deboned chicken meat incorporation. Colour variables ( CIE a* and b*, and Whiteness index) varied significantly (P < 0.05), with redness (a*) being the variable most influenced by the incorporation of mechanically deboned chicken meat. Whiteness index decreased with added mechanically deboned chicken meat and grape pomace extract. Response surface was applied to identify formulations with higher acceptance scores. Correspondence analysis of open-ended comments complemented the information obtained from overall acceptance, adding valuable descriptive attributes of nugget samples. Thus, addition of grape pomace extract up to 120 mg/kg and mechanically deboned chicken meat up to 15 g/100 g did not adversely affect the perceived appearance of chicken nuggets. Mechanically deboned chicken meat and grape pomace extract can be successfully used for the elaboration of novel products, for different market segments, with healthy connotations highlighted by antioxidant properties retained by the grape pomace extract.

Effects of alfalfa flavonoids on broiler performance, meat quality, and gene expression

Two hundred and forty 1-d-old Arbor Acre female broilers were used to study the effects of alfalfa flavonoids (AF) on broiler performance, meat quality, and gene expression. Chicken were fed with basal diet supplemented with AF at 0, 5, 10, or 15 mg kg−1 diet for a period of 42 d. Growth performance, meat quality, antioxidant effect and lipoprotein lipase (LPL), adipose triglyceride lipase (ATGL), peroxisome proliferator-activated receptor γ (PPARγ), and fatty acid synthase (FAS) gene expressions were investigated. Results showed that AF inclusion in the diet enhanced the body weight (BW) at 42 d of age and the average daily gain from 0 to 42 d, decreased the total cholesterol (TC) and low-density lipoprotein cholesterol (LDL) levels and increased HDL level in the serum, enhanced the superoxide dismutase (SOD), catalase (CAT), total antioxidant capacity (T-AOC), and glutathione peroxidase (GSH-Px), and decreased the malondialdehyde (MDA) concentrations in the serum. Also, AF supplementation decreased the abdomen fat rate, marble, and the drip loss and storage loss after the storage for 96 h. Gene expressions’ results showed that AF inclusion decreased the FAS expression and increased the LPL, PPARγ, and ATGL expressions in the liver and adipose tissues, especially when the AF inclusion level was 15 mg kg−1 diet. These results indicate that AF were found to be effective for average daily gain and breast percentage promoting, meat quality and antioxidant activity improvement via upregulating the LPL, ATGL, PPARγ, and downregulating the FAS expression in adipose and liver tissues.

Effects of alfalfa flavonoids on broiler performance, meat quality, and gene expression

Two hundred and forty 1-d-old Arbor Acre female broilers were used to study the effects of alfalfa flavonoids (AF) on broiler performance, meat quality, and gene expression. Chicken were fed with basal diet supplemented with AF at 0, 5, 10, or 15 mg kg−1 diet for a period of 42 d. Growth performance, meat quality, antioxidant effect and lipoprotein lipase (LPL), adipose triglyceride lipase (ATGL), peroxisome proliferator-activated receptor γ (PPARγ), and fatty acid synthase (FAS) gene expressions were investigated. Results showed that AF inclusion in the diet enhanced the body weight (BW) at 42 d of age and the average daily gain from 0 to 42 d, decreased the total cholesterol (TC) and low-density lipoprotein cholesterol (LDL) levels and increased HDL level in the serum, enhanced the superoxide dismutase (SOD), catalase (CAT), total antioxidant capacity (T-AOC), and glutathione peroxidase (GSH-Px), and decreased the malondialdehyde (MDA) concentrations in the serum. Also, AF supplementation decreased the abdomen fat rate, marble, and the drip loss and storage loss after the storage for 96 h. Gene expressions’ results showed that AF inclusion decreased the FAS expression and increased the LPL, PPARγ, and ATGL expressions in the liver and adipose tissues, especially when the AF inclusion level was 15 mg kg−1 diet. These results indicate that AF were found to be effective for average daily gain and breast percentage promoting, meat quality and antioxidant activity improvement via upregulating the LPL, ATGL, PPARγ, and downregulating the FAS expression in adipose and liver tissues.

Oxidative damage to poultry: from farm to fork

Poultry and poultry meat are particularly susceptible to oxidative reactions. Oxidation processes have been for decades the focus of animal and meat scientists owing to the negative impact of these reactions on animal growth, performance, and food quality. Lipid oxidation has been recognized a major threat to the quality of processed poultry products. The recent discoveries on the occurrence of protein oxidation in muscle foods have increased the scientific and technological interest in a topic that broadens the horizons of food biochemistry into innovative fields. Furthermore, in recent years we have witnessed a growing interest in consumers on the impact of diet and oxidation on health and aging. Hence, the general description of oxidative reactions as harmful phenomena goes beyond the actual impact on animal production and food quality and reaches the potential influence of oxidized foods on consumer health. Likewise, the current antioxidant strategies aim for the protection of the living tissues, the food systems, and a potential health benefit in the consumer upon ingestion. Along these lines, the application of phytochemicals and other microelements (Se, Cu) with antioxidant potential in the feeds or directly in the meat product are strategies of substantial significance. The present paper reviews in a concise manner the most relevant and novel aspects of the mechanisms and consequences of oxidative reactions in poultry and poultry meat, and describes current antioxidant strategies against these undesirable reactions.

The influence of acid whey and mustard seed on lipid oxidation of organic fermented sausage without nitrite

BACKGROUND

The influence of the addition of mustard seed and acid whey on the stability of nitrite-free organic fermented sausage during 90 days of vacuum storage was investigated by measuring primary and secondary products of lipid oxidation, changes in fatty acid composition and antioxidant capacity, as well as water activity.

RESULTS

The native and autoclaved mustard seed with acid whey can be used in the composition of organic fermented sausage without nitrite with beneficial effect on pH, water activity, antioxidant capacity and oxidation stability during vacuum storage. The use of the combination of acid whey and mustard seed resulted in an effective decrease in pH of organic fermented sausage during fermentation. The inclusion of mustard seed to the sausage with acid whey significantly increased the capacity of stuffing to capture the radical cation ABTS. During the whole storage period the TBARS (thiobarbituric acid reactive substances) values of salted sausage samples with the addition of acid whey with combination of mustard seed were similar to the control sample with curing agent.

CONCLUSION

In general, results suggest that mustard seed with combination of acid whey can be successfully applied to protect organic fermented sausages without nitrite from lipid oxidation.

Characterisation of Mediterranean grape pomace seed and skin extracts: polyphenolic content and antioxidant activity

Grape pomace seeds and skins from different Mediterranean varieties (Grenache [GRE], Syrah [SYR], Carignan [CAR], Mourvèdre [MOU] and Alicante [ALI]) were extracted using water and water/ethanol 70% in order to develop edible extracts (an aqueous extract [EAQ] and a 70% hydro-alcoholic extract [EA70]) for potential use in nutraceutical or cosmetic formulations. In this study, global content (total polyphenols, total anthocyanins and total tannins), flavan-3-ols and anthocyanins were assessed using HPLC-UV-Fluo-MSⁿ. In addition, extract potential was evaluated by four different assays: Oxygen Radical Absorbance Capacity (ORAC), Ferric Reducing Antioxidant Potential assay (FRAP), Trolox equivalent antioxidant capacity (TEAC) or ABTS assay and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. As expected, seed pomace extracts contained higher amounts of polyphenols then skin pomace extracts. Indeed, seeds from Syrah contained a particularly important amount of total polyphenols and tannins in both type of extract (up to 215.84 ± 1.47 mg of gallic acid equivalent [GAE]/g dry weight (DW) and 455.42 ± 1.84 mg/g DW, respectively). These extracts also expressed the highest antioxidant potential with every test. For skins, the maximum total phenolic was found in Alicante EAQ (196.71 ± 0.37 mg GAE/g DW) and in Syrah EA70 (224.92 ± 0.18 mg GAE/g DW). Results obtained in this article constitute a useful tool for the pre-selection of grape pomace seed and skin extracts for nutraceutical purposes.

Effect of Grape Pomace Powder Addition on TBARS and Color of Cooked Pork Sausages during Storage

To determine the effects of grape skin and seed pomace (GSP) additions on the lipid oxidation susceptibility and the color change of cooked pork sausages, the chemical characteristics of GSP itself and the addition for two different levels of GSP (0.5 and 1.0% GSP, respectively) to sausages were examined. Both the redness and blueness of the GSP were significantly reduced as the pH level was increased from 5 to 7, but a reverse result was determined in the color tint and yellowness (p<0.05). The GSP polyphenol and flavonoid contents were influenced by the percentages of methanol solvents, and more flavonoids were established when 100% of methanol was applied as a solvent to the GSP. But, similar results were not observed in the polyphenol of GSP. In cooked pork sausages, significant decreases in the lightness and redness were found in both the 0.5% and 1.0% of GSP sausages during the storage period (p<0.05). However, an incompatible effect was observed in terms of yellowness, which increased as compared to the control sausage after 6 days of storage. The 0.5% addition of GSP decreased the levels of TBARS (p<0.05), but the ability of GSP to minimize lipid oxidation was not dose dependent. Therefore, the results indicated that the GSP is an efficient suppressor of lipid oxidation and has latent effects as a natural antioxidant when 0.5% of GSP is added to the cooked pork sausages.

By-product from decoction process of Hibiscus sabdariffa L. calyces as a source of polyphenols and dietary fiber

BACKGROUND

Dietary fiber (DF) and antioxidant compounds are widely used as functional ingredients. The market in this field is competitive and the search for new types of quality ingredients for the food industry is intensifying. The aim of this study was to evaluate the composition and antioxidant activity of by-products generated during the decoction of calyces of four Mexican Hibiscus sabdariffa L. cultivars ('Criolla', 'China', 'Rosalis' and 'Tecoanapa') in order to assess them as a source of functional ingredients.

RESULTS

Some calyx components were partially transferred to the beverage during the decoction process, while most were retained in the decoction residues. These by-products proved to be a good source of DF (407.4-457.0 g kg⁻¹ dry matter) and natural antioxidants (50.7-121.8 µmol Trolox equivalent g⁻¹ dry matter).

CONCLUSION

The decoction process extracted some soluble carbohydrates, ash and some extractable polyphenols. The DF content changed in the dried residues, which could be considered as high-DF materials with a high proportion of soluble DF (∼20% of total DF) and considerable antioxidant capacity. These by-products could be used as an antioxidant DF source.

Individual and combined effects of genistein and hesperidin supplementation on meat quality in meat-type broiler chickens

BACKGROUND

There is growing interest in improving the production and meat quality of farm animals through dietary supplementation with phytochemical (e.g. flavonoids)-rich plants and/or their extracts. This study was conducted to analyse the supplemental effects of two purified flavonoids (genistein and hesperidin) individually and in combination on the oxidative status, sensory score and quality of breast meat in meat-type broiler chickens.

RESULTS

A significant increase (P < 0.05) in meat colour (L* score) and pH was observed for the group supplemented with 20 mg kg(-1) genistein and hesperidin. Water-holding capacity was also improved significantly (P < 0.01) for all genistein- and hesperidin-treated groups, while the sensory quality of breast meat remained unaffected. Lipid oxidation of breast meat was reduced significantly (P < 0.01) at 0 and 15 days of refrigeration in a dose-dependent manner for all supplemented groups. Meanwhile, some treated groups showed improved (P < 0.05) body weight, feed/gain ratio and hot carcass weight.

CONCLUSION

Genistein and hesperidin supplementation to broilers improved meat quality in a dose-dependent fashion, with pronounced effects of combined treatment. The results indicated that purified flavonoids such as genistein and hesperidin could potentially be used as feed additives in broiler production to promote meat quality.

Grape pomace as a sustainable source of bioactive compounds: extraction, characterization, and biotechnological applications of phenolics

Grape pomaces (GPs) are characterized by high contents of phenolics due to an incomplete extraction during the winemaking process. These phenolics are secondary plant metabolites with potential beneficial effects on human health because of their antioxidant activity and antimicrobial, antiviral, and anti-inflammatory properties. Therefore, GP constitutes an inexpensive source for the extraction of phytochemicals that can be used in the pharmaceutical, cosmetic, and food industries. As a result of the increased attention to sustainability of agricultural practices, efforts have been made to use GP in different fields of industry. Thus, it is necessary to have efficient extraction techniques to achieve good recoveries of compounds. In this respect, sensitive and selective analytical methods have been tried for the characterization of phenolic extracts. This review summarizes the most recent developments in the extraction of polyphenols from GPs. Furthermore, the techniques used for characterization of extracts are explained, with emphasis on sample preparation, separation, and analysis of phenolics. Finally, the possible applications of GP extracts in diverse biotechnological fields are also discussed.

Antioxidant action of ganghwayakssuk (Artemisia princeps Pamp.) in combination with ascorbic acid to increase the shelf life in raw and deep fried chicken nuggets

Raw and deep fried chicken nuggets containing various levels of ganghwayakssuk ethanolic extract (GE) in combination with ascorbic acid (Aa) were evaluated for shelf-life during refrigerated storage (4°C). The pH and color (lightness, redness, and yellowness) values of raw and deep fried samples were significantly affected by the addition of GE (P<0.05). All antioxidant combinations except for Aa+GE 0.01 were effective at delaying lipid oxidation (CD, POV, and TBARS) when compared to the control or Aa. Raw samples with GE 0.2 and Aa+GE 0.1 exhibited lower bacterial populations during storage. The sensory characteristics (color, juiciness, flavor, tenderness, and overall acceptability) did not differ significantly in all deep fried chicken nugget samples, except color, whereas storage time had a significant effect (P<0.05). The results suggest the possibility of utilizing raw and deep fried chicken nuggets with a mixture of ganghwayakssuk and ascorbic acid for the increase of shelf-life and quality.