Influence of peanut skin extract on shelf-life of sheep patties

The Effects of Sunflower and Maize Crop Residue Extracts as a New Ingredient on the Quality Properties of Pork Liver Pâtés

The present study aimed to evaluate the antioxidant capacity of ethanolic extracts from post-harvest sunflower and maize stalk residues, and their impact on the chemical composition, physicochemical parameters, lipid oxidative stability, microbiological properties, and sensory characteristics of pork liver pâtés over a 90-day storage period. Four formulations were prepared: a control group (CON), a batch with butylated hydroxytoluene as a synthetic antioxidant (BHT), 1% ethanolic extract from sunflower residues (SSRE), and 1% ethanolic extract from maize residues (MSRE). The MSRE had a higher total phenol content and showed better antioxidant activity relative to the SSRE (p < 0.01). The addition of SSRE decreased the lightness and increased the redness in the pork liver pâtés, with these pâtés showing the highest total color difference compared to the control (p < 0.01). The crop extracts increased the n-6 and total PUFA contents in pâtés and improved the PUFA/SFA ratio (p < 0.01). Formulations containing crop residue extracts showed higher TBARs and POV values than the control and BHT group (p < 0.01), indicating a pro-oxidant effect and accelerated lipid oxidation in pâtés during storage. As far as microbiological quality, the presence of crop residue extracts decreased the total viable count, lactic acid bacteria, and psychotropic aerobic bacteria (p < 0.01). The incorporation of crop extracts in the pork pâtés impaired their sensory quality, particularly color, odor, aroma, and flavor, and decreased their overall acceptability. These results indicated that, while the crop residue extracts were not as effective as synthetic antioxidants in preserving the lipid stability of pâtés, they demonstrated potential for enhancing the microbial quality of this type of meat product.

Harnessing Natural Antioxidants for Enhancing Food Shelf Life: Exploring Sources and Applications in the Food Industry

Consumers are increasingly showing in maintaining a healthy dietary regimen, while food manufacturers are striving to develop products that possess an extended shelf-life to meet the demands of the market. Numerous studies have been conducted to identify natural sources that contribute to the preservation of perishable food derived from animals and plants, thereby prolonging its shelf life. Hence, the present study focuses on the identification of both natural sources of antioxidants and their applications in the development of novel food products, as well as their potential for enhancing product shelf-life. The origins of antioxidants in nature encompass a diverse range of products, including propolis, beebread, and extracts derived through various physical-chemical processes. Currently, there is a growing body of research being conducted to evaluate the effectiveness of natural antioxidants in the processing and preservation of various food products, including meat and meat products, milk and dairy products, bakery products, and bee products. The prioritization of discovering novel sources of natural antioxidants is a crucial concern for the meat, milk, and other food industries. Additionally, the development of effective methods for applying these natural antioxidants is a significant objective in the food industry.

Phenolic Fraction from Peanut (Arachis hypogaea L.) By-product: Innovative Extraction Techniques and New Encapsulation Trends for Its Valorization

Peanut skin is a by-product rich in bioactive compounds with high nutritional and pharmaceutical values. The phenolic fraction, rich in proanthocyanidins/procyanidins, is a relevant class of bioactive compounds, which has been increasingly applied as functional ingredients for food and pharmaceutical applications and is mostly recovered from peanut skins through low-pressure extraction methods. Therefore, the use of green high-pressure extractions is an interesting alternative to value this peanut by-product. This review addresses the benefits of the phenolic fraction recovered from peanut skin, with a focus on proanthocyanin/procyanidin compounds, and discusses the improvement of their activity, bioavailability, and protection, by methods such as encapsulation. Different applications for the proanthocyanidins, in the food and pharmaceutical industries, are also explored. Additionally, high-pressure green extraction methods, combined with micro/nanoencapsulation, using wall material derived from peanut industrial processing, may represent a promising biorefinery strategy to improve the bioavailability of proanthocyanidins recovered from underutilized peanut skins.

An overview of the natural antimicrobial alternatives for sheep meat preservation

Sheep meat is consumed and appreciated all over the world for its nutritional value and flavor. However, this meat is very perishable and easily subjected to the action of both spoilage and pathogenic microorganisms. For this reason, in combination with cold storage, effective preservation techniques are required. There is increasing interest in the application of natural antimicrobials, such as essential oils, extracts, spices, and by-products of the food industry. This review analyses the studies on natural antimicrobials in sheep meat and sheep meat products and gathers evidence about the encouraging results achieved on the reduction and/or elimination of spoilage and pathogenic microorganisms. The use of these natural antimicrobial alternatives might open up important perspectives for industrial application, considering that this specific meat is often traded over long distances. In fact, on the basis of scientific literature, natural antimicrobials can be considered a sustainable and affordable alternative to extend the shelf life of sheep meat and guarantee its safety, although many factors need to be further investigated, such as the sensory impact, potential toxicity, and economic aspects. For all these issues, investigated in some of the studies reviewed here, it is fundamental to obtain the antimicrobial effect with the minimum amount of effective substance to avoid sensory modifications, toxic effects, and unbearable costs. This study sets foundations for the possible direction of future studies, which will contribute to identify effective solutions for industrial applications of natural antimicrobials in the sheep meat industry.

Peanut skin phenolics obtained by green solvent extraction: characterization and antioxidant activity in pure chia oil and chia oil in water (O/W) emulsion

BACKGROUND

The peanut skin (PS) is considered as an industrial waste with undervalued applications. Although several studies report potent antioxidant capacities of PS phenolics, the effectiveness in highly unsaturated lipid systems has not yet been evaluated. The objectives of the present study were two-fold: (i) to characterize a PS phenolic extract (PSE) obtained by means of a green technology and (ii) to evaluate its antioxidant efficacy on pure chia oil and chia oil in water (O/W) acid emulsion.

RESULTS

PSE was composed mainly of monomeric and condensed flavonoids (procyanidin and proanthocyanidin oligomers). PSE displayed strong antioxidant properties as measured by different reducing power and radical scavenging capacities [IC₅₀  = 0.36 μg dry extract (DE) mL^-1 for ferric reducing antioxidant power; IC₅₀  = 4.96 μg DE mL^-1 for 2,2-diphenyl-1-picrylhydrazyl (DPPH)^• ; IC₅₀  = 6.01 μg DE mL^-1 for 2,2'-azinobis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS)^•+ ; IC₅₀  = 2.62 μg DE mL^-1 for HO^• ]. It also showed high antioxidant efficacy when tested in pure chia oil under accelerated oxidation conditions (Rancimat, 100 °C). When added to the O/W emulsions maintained at 40 °C for 15 days, the PSE was more effective than a synthetic antioxidant (tert-butylhydroquinone) with respect to minimizing the formation and degradation of lipid hydroperoxides.

CONCLUSIONS

The antioxidant efficacy of PSE was primarily attributed to the abundance of compounds with a high number of phenolic-OH groups. Because they were found to cover a relatively wide range of partition coefficients, the antioxidant properties could be also enhanced by effect of both interfacial and solubility phenomena. All of these features allow the potential use of PSE as a natural antioxidant in different types of foods, including acid emulsion systems. © 2021 Society of Chemical Industry.

An overview on extraction, composition, bioactivity and food applications of peanut phenolics

Peanuts contain a diverse and vast array of phenolic compounds having important biological properties. They are allocated mostly in the seed coat (skin), an industrial waste with minor and undervalued applications. In the last few years, a considerable amount of scientific knowledge about extraction, composition, bioactivities and health benefits of peanut skin phenolics has been generated. The present review was focused on four main aspects: a) extraction methods and technologies for obtaining peanut skin phenolics with an emphasis on green-solvent extraction processes; b) variations in chemical profiles including those due to genetic variability, extraction methodologies and process-related issues; c) bioactive properties, especially antioxidant activities in food and biological systems; d) update of promising food applications. The revision was also aimed at identifying areas where knowledge is insufficient and to set priorities for further research.

Blackcurrant (Ribes nigrum L.) and Kamchatka Honeysuckle (Lonicera caerulea var. Kamtschatica) Extract Effects on Technological Properties, Sensory Quality, and Lipid Oxidation of Raw-Cooked Meat Product (Frankfurters)

Oxidation is one of the most prevalent factors responsible for meat product deterioration. Due to their potential health risks, commonly used synthetic antioxidants are beginning to be frowned upon by customers. The industry is searching for a natural replacement. In our study, we incorporated blackcurrant (Ribes nigrum L.) and Kamchatka honeysuckle (Lonicera caerulea var. Kamtschatica) extracts into raw-cooked meat products (frankfurters) as natural antioxidants. We observed that both extracts at concentrations of 3 mL·kg^-1 were able to significantly (α = 0.05) postpone lipid oxidation in our samples, with results comparable to vitamin C (0.5 mg·kg^-1) addition. Moreover, we did not observe negative effects of the extracts on the product's color, pH, or textural properties. Negative results were reported in the sensory evaluation of honeysuckle addition samples. This could have been caused by the natural strong and bitter taste of honeysuckle, which was transferred to the extracts and, subsequently, into the meat product.

Morphological, biochemical and histological effects of aqueous extracts of peanut (Arachis hypogaea) on swiss mice in different diets

PURPOSE

To evaluate the morphological, biochemical, and histological effects of aqueous extracts of peanut (skinless and added to 1% skin) in Swiss mice submitted to a high-fat diet.

METHODS

Forty male Swiss mice were divided into four groups (n=10 per group): GI) normocaloric diet; GII) high-fat diet; GIII) high-fat diet + 0.5 mL of peanut extract; GIV) high-fat diet + 0.5 mL of peanut extract + 1% peanut skin. The animals were weighed weekly and euthanized after 12 weeks for histopathological and biochemical analyses. The study was approved by the Animal Use Ethics Committee.

RESULTS

The animals in the GIV group had higher body weight when compared to the other ones. Increase in total cholesterol in GIII, increase in blood glucose in groups GII, GIII and GIV, decrease in serum low-density lipoprotein (LDL) concentration in groups GI and GIV and increase in serum concentration of C-reactive protein in GII were seen. The presence of vacuolar fat deposits was found in animal livers from GII.

CONCLUSIONS

The extracts improved the plasma concentrations of animals that received a high-fat diet, including preventing morphological damage to liver tissue. These benefits were enhanced by the association of peanut shells with the extract.

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.

Composição físico-química e compostos bioativos do extrato aquoso de amendoim sem pele e enriquecido com pele

Resumo Objetivou-se realizar a caracterização físico-química e dos compostos bioativos do extrato aquoso de amendoim sem pele e acrescido de 1% de pele. Os extratos aquosos de amendoim sem e com pele foram caracterizados quanto aos parâmetros: umidade, extrato seco total, cinzas, lipídios, proteínas, teor de sólidos solúveis, acidez titulável, pH, carboidrato e fibras totais, além de compostos fenólicos e flavonoides. Os percentuais de umidade encontrados foram elevados em todas as amostras, resultante de sua base de extrato aquoso produzido na proporção 1:8 (amendoim:água). Observou-se que os extratos aquosos de amendoim sem pele e acrescido de 1% de pele não apresentaram diferença significativa entre si para os parâmetros de pH, como também para sólidos solúveis totais, lipídios e carboidratos. No entanto, a acidez, proteínas, fibras e cinzas apresentaram diferença estatística. Na determinação de compostos fenólicos, notou-se que o extrato aquoso de amendoim com pele apresentou uma quantidade maior quando comparado ao sem pele. Quanto aos flavonoides, a maior quantidade também foi encontrada na amostra com pele, apresentando uma diferença média de 2,52 µg/100 g base úmida. Os extratos aquosos de amendoim com e sem pele mostraram ser uma valiosa alternativa para um melhor aproveitamento do amendoim, proporcionando à população um produto nutricional. A bebida acrescida de 1% de pele enriqueceu o produto quanto ao potencial antioxidante devido às suas maiores concentrações de compostos fenólicos totais e flavonoides.

Extracts of Peanut Skins as a Source of Bioactive Compounds: Methodology and Applications

Peanut skins are a waste product of the peanut processing industry with little commercial value. They are also significant sources of the polyphenolic compounds that are noted for their bioactivity. The extraction procedures for these compounds range from simple single solvent extracts to sophisticated separation schemes to isolate and identify the large range of compounds present. To take advantage of the bioactivities attributed to the polyphenols present, a range of products both edible and nonedible containing peanut skin extracts have been developed. This review presents the range of studies to date that are dedicated to extracting these compounds from peanut skins and their various applications.

Natural Antioxidants from Seeds and Their Application in Meat Products

The use of synthetic antioxidants in the food industry has raised important questions about the effects of prolonged consumption on human health. On top of that, the consumption of meat products has been changing due to the awareness generated by health-related organizations. In this sense, exploring strategies to develop and produce healthier meat products has become a paramount concern. Several studies explored the composition of several seeds to characterize and explore the compounds with antioxidant activity, which are mainly composed of polyphenols. The use of antioxidant extracts in meat products has shown important results to delay the oxidative reactions in meat products derived from the processing and storage of meat products. Moreover, these extracts can also replace synthetic antioxidants and preserve the quality of meat products. Therefore, the aims of this review are first, to present the sources and compounds with antioxidant activity in seeds, and second, to discuss their protective effect against oxidative reactions in meat products.

Physicochemical Composition and Nutritional Properties of Deer Burger Enhanced with Healthier Oils

Deer meat is characterized by low fat and cholesterol contents and high amounts of protein and polyunsaturated fatty acids. In this regard, the aim of this work was to assess the influence of pork backfat substitution by healthier oils on chemical composition, fatty acid profile, texture profile and sensory analysis of deer burger. In addition, pH, color parameters and lipid oxidation were evaluated at 0, 6, 12 and 18 days of storage. For this study, four different treatments of deer burgers-100% pork backfat, 100% tiger nut oil, 100% chia oil, and 100% linseed oil-were elaborated. The fat replacement reduced fat and protein contents and increased moisture amounts, whereas ashes and texture parameters of deer burgers were not affected. Fatty acid profile was significantly improved with the animal fat replacement. In this regard, a significant decrease in saturated fatty acids was found in all reformulated batches, whereas in chia and linseed burger samples a dramatic increase in polyunsaturated fatty acids, omega-3 content and a reduction of n-3/n-6 ratio was observed. In the deer burger prepared with tiger nut oil a significant increase in monounsaturated fatty acids was found. Another important aspect is that the replacement of animal fat by tiger nut or linseed oil emulsion did not affect the global acceptance of deer burgers. Regarding color parameters, redness was the most affected during the whole display presenting a reduction around 50% after 18 days of storage. On the other hand, thiobarbituric acid reactive substances (TBARS) values were also affected by fat replacement and storage time, observing the highest values (2.43 mg MDA/kg) in deer burgers prepared with chia at the end of refrigerated period. Finally, from a commercial point of view, the possibility of making claims such as "low fat burgers", "reduced saturated fat" or "high content of omega-3" makes the reformulated burgers more attractive to the consumer.

Antioxidant and antimicrobial properties of oregano extract (Origani vulgaris herba L.)

Introduction. Some ingredients of plant origin possess both antioxidant and bacteriostatic properties. If used in the food industry, they can inhibit microbiological and oxidative damage, thus increasing the shelf life of meat products. Oregano extract is one of such substances, which means that it can be used as an antioxidant and preservative. Therefore, the study of this plant has a significant theoretical and practical potential for the food industry. Study objects and methods. The present research featured ground trimmed beef. The samples with 20% of fat tissue were used to determine the microbiological parameters, while the samples with 30% of fat were used to obtain data on oxidative stability. The control sample contained no additional ingredients. The sample with food additives was pre-treated with acidity regulators and antioxidants, namely sodium acetate E262, ascorbic acid E300, sodium ascorbate E301, sodium citrate E331, and rosemary extract E392. The sample with oregano extract was pre-treated with oregano extract (Origani vulgaris herba L.) in the ratio of 5 g of extract per 1 kg of meat. The extract had been dissolved in 100 g of water. The samples were stored at 4 ± 2°C for 12 days. A CM5 spectrophotometer (Konica Minolta, Japan) was used to determine the color characteristics. The induction period of oxidative stability was determined using an Oxitest oxidative stability analyzer (Velp Scientifica, Italy). The studies were conducted in Austria, Linz. Results and discussion. Oregano extract stabilized the redness rating. For the sample with oregano extract, the induction period of oxidative stability was twice as long as for the control sample and the sample with antioxidants. In addition, oregano inhibited the growth of aerobic and anaerobic microorganisms. Conclusion. The antioxidant and antimicrobial properties of oregano extract prolong the shelf life of ground beef, which makes it possible to reduce the amount of food additives.

Phenolic Compounds from Nuts: Extraction, Chemical Profiles, and Bioactivity

Nuts contain a vast array of phenolic compounds having important biological properties. They include substances allocated into the five major groups named phenolic acids, flavonoids, tannins, phenolic lignans, and stilbene derivatives. The complexity in composition does not allow for setting a universal extraction procedure suitable for extraction of all nut phenolics. The use of non-conventional extraction techniques, such as those based on microwave, ultrasound, and compressed fluids, combined with generally recognized as safe solvents is gaining major interest. With regard to the latter, ethanol, water, and ethanol-water mixtures have proven to be effective as extracting solvents and allow for clean, safe, and low-cost extraction operations. In recent years, there has been an increasing interest in biological properties of natural phenolic compounds, especially on their role in the prevention of several diseases in which oxidative stress reactions are involved. This review provides an updated and comprehensive overview on nut phenolic extraction and their chemical profiles and bioactive properties.

Inclusion of Ethanol Extract of Mesquite Leaves to Enhance the Oxidative Stability of Pork Patties

The lipid oxidation (LOX) of pork meat has been associated with loss of quality and shorter shelf life. Consequently, synthetic antioxidants have been used to reduce this process, but their use has shown potential health risks. Thus, the use of natural ingredients has been suggested as a strategy to prevent LOX. This study aimed to assess the oxidative stability of pork patties treated with ethanol extract of mesquite leaf (EEML) during storage. Furthermore, the polyphenol composition (TPC, total phenolic, TFC, total flavonoid) and antioxidant activity (antiradical and reducing power activity) of EEML were also evaluated. For this study, five treatments (CN (control), without antioxidant; Asc, ascorbic acid 0.02%; BHT, butylated hydroxytoluene 0.02%; EEML1, 0.05%; and EEML2, 0.1%) of pork patties were applied. Patty samples were stored at 4 °C, and physicochemical parameters, lipid oxidation, total antioxidant capacity of the meat, and sensory analysis were evaluated at 0, 3, 7, and 10 days of storage. EEML presented high values of TPC (278.5 mg gallic acid equivalent (GAE)/g) and TFC (226.8 mg rutin equivalents (RE)/g) levels. The addition of EEML did not modify the chemical composition of the pork patties. On the other hand, colour parameters were affected by the inclusion of EEML in pork patties, presenting the lowest a* in the CN group compared to the other groups after 10 days storage. Lipid oxidation increased during the whole period, showing the lowest (P < 0.05) conjugated dienes and thiobarbituric acid reactive substances (TBARS) values (40% and 90% of inhibition, respectively) compared to the CN group. Regarding sensory analysis, there were no significant differences in colour, appearance, odour, flavour, juiciness, fat sensation, and firmness of the cooked pork patties among treatments. These results suggest that EEML has great potential as a natural antioxidant for meat products.

Drumstick (Moringa oleifera) Flower as an Antioxidant Dietary Fibre in Chicken Meat Nuggets

The present work investigated the efficacy of Moringa flower (MF) extract to develop a functional chicken product. Three groups of cooked chicken nuggets—control (C), T1 (with 1% MF) and T2 (2% MF)—were elaborated and their physicochemical, nutritional, storage stability and sensory attributes were assessed during refrigerated storage at 4 °C up to 20 days. In addition, MF extracts were characterised in terms of chemical composition, total phenolic content and its components using high-performance liquid chromatography with a diode-array detector (HPLC-DAD), dietary fibre and antioxidant capacity. MF contained high protein (17.87 ± 0.28 dry matter), dietary fibre (36.14 ± 0.77 dry matter) and total phenolics (18.34 ± 1.16 to 19.49 ± 1.35 mg gallic acid equivalent (GAE)/g dry matter) content. The treated nuggets (T1 and T2) had significantly enhanced cooking yield, emulsion stability, ash, protein, total phenolics and dietary fibre compared to control. Incorporation of MF extract at 2% not only significantly reduced the redness/increased the lightness, but also decreased the hardness, gumminess and chewiness of the product compared to control. Moreover, the addition of MF extract significantly improved the oxidative stability and odour scores by reducing lipid oxidation during storage time. Sensory attributes of nuggets were not affected by the addition of MF extract and the products remained stable and acceptable even on 15th day of storage. These results showed that MF extract could be considered as an effective natural functional ingredient for quality improvement and reducing lipid oxidation in cooked chicken nuggets.

Guarana seed extracts as a useful strategy to extend the shelf life of pork patties: UHPLC-ESI/QTOF phenolic profile and impact on microbial inactivation, lipid and protein oxidation and antioxidant capacity

The antioxidant and antimicrobial effects of guarana seed extracts (GSE) added to pork patties were evaluated for 18 days storage at 2 ± 1 °C. Five treatments were prepared: i) without natural antioxidant [control (negative control)], ii) with BHT at 200 mg/kg (positive control), and iii) with three different concentrations: 250  mg/kg (guarana seed low dose-GSL), 500  mg/kg (guarana seed medium dose-GSM) and 1000  mg/kg (guarana seed high dose-GSH) of guarana extracts, respectively. The pH, instrumental colour (CIE L*, a*, b*), total viable counts (TVC), Pseudomonas spp. counts and lactic acid bacteria (LAB) counts, 2-thiobarbituric acid reactive substances (TBARS) and carbonyl content were determined after 0, 7, 11, 15 and 18 days of storage period. The in vitro antioxidant activity together with the phenolic profile of GSE was also studied. Microbial analysis showed that GSE had no antimicrobial activity on pork patties. The untargeted UHPLC-ESI-QTOF approach confirmed the wide phenolic composition of GSE able to explain the antioxidant power (28.2 g/kg of phenolic equivalents). Low doses (GSL) of GSE were able to preserve the values of colour parameters, obtaining higher L*, a* and b* values during storage, which is reflected in the lowest colour differences during storage (ΔE*_0-18 = 4.56). TBARS and carbonyls values in GSE added samples were lower than control and BHT ones. GSL and GSM provided better results than the synthetic antioxidant (0.08 and 0.07 vs 0.18 mg MDA/kg; 2.47 and 3.13 vs 3.23 nmol/mg, for GSL and GSM vs BHT, respectively). These findings show that GSE are very effective against colour deterioration, lipid and protein oxidation in pork patties and possessing the potential to be used as natural antioxidants.

Chitosan active films containing agro-industrial residue extracts for shelf life extension of chicken restructured product

This study aimed to develop chitosan films incorporating natural antioxidants from peanut skin (EPS) and pink pepper residue (EPP) extracts, as well as to evaluate their effects on lipid oxidation, pH, color, and microbial counts of a restructured chicken product. EPS had higher phenolic content and antioxidant activity compared to EPP. When both extracts were applied to chicken meat and the chitosan films, there were no differences for color, pH and total mesophilic counts compared to control at the end of the storage period. For lipid oxidation (peroxide value and thiobarbituric acid reactive substances), both extracts proved to be as effective as butylated hydroxytoluene to maintain the oxidative stability of the chicken product. The microbial counts of psychrotrophic microorganisms were significantly lower for treatments with active films. Chitosan active films with residue extracts may maintain the quality of chicken products due to their antioxidant and antimicrobial potential.

Effect of natural antioxidants on physicochemical properties and lipid stability of pork liver pâté manufactured with healthy oils during refrigerated storage

This study aimed to evaluate the effect of natural antioxidants in pork liver pâté manufactured with the combination of pork backfat, fish oil and olive oil. Phenolic composition of beer residue extract (BRE), chestnut leaves extract (CLE) and peanut skin extract (PSE) were identified and quantified. Four batches of pork liver pâté were produced: control, BRE, CLE and PSE. Pork liver pâté was evaluated for proximate composition, pH, instrumental colour, free fatty acid content, lipid-derived volatile compounds and lipid oxidation. The major compounds of BRE were benzoic acid and catechin (1.79 and 1.51 mg/L, respectively), in CLE were ellagic and gallic acid (10.26 and 2.70 mg/100 g fresh weight) and in PSE was catechin (20.66 mg/100 g dry weight). Proximate composition was similar for all batches. The pH values were not influenced by any natural antioxidant. Colour parameters were affected by storage time but slight differences were observed among batches. Lipid stability (TBARS and lipid-derived volatile compounds) was not remarkably affected by addition of natural extracts.

Effect of natural antioxidants in Spanish salchichón elaborated with encapsulated n-3 long chain fatty acids in konjac glucomannan matrix

The effect of natural antioxidants on physicochemical properties, lipid and protein oxidation, volatile compounds and free fatty acids (FFA) were determined in Spanish salchichón enriched with n-3 fatty acids encapsulated and stabilized in konjac matrix. Phenolic compounds of beer residue extract (BRE), chestnut leaves extract (CLE) and peanut skin extract (PSE) were also identified and quantified. Five batches of salchichón were prepared: control (CON, without antioxidants), butylated hydroxytoluene (BHT), BRE, CLE and PSE. The main phenolic compounds were catechin and benzoic acid for BRE, gallic acid and catechin for CLE and catechin and protocatechuic acid for PSE. Statistical analysis did not show significant differences on chemical composition among treatments. Reductions in luminosity (P<0.05) and pH (P<0.001) were observed with the CLE batch, whereas the other colour parameters were not affected by the addition of natural antioxidants. Finally, the inclusion of antioxidants (P<0.001) decreased the hexanal content, whereas the FFA content increased by the addition of natural extracts.