Evaluation of the sensory and physical properties of meat and fish derivatives containing grape pomace powders

High-Hydrostatic-Pressure-Stabilized White Grape Pomace to Improve the Oxidative Stability of Dry-Cured Sausages ("Salchichón")

White grape pomace (winery by-product) stabilized by blanching and high hydrostatic pressure has recently been successful at delaying lipid oxidation in burgers. The aim of this study was to investigate whether it can also delay lipid oxidation in dry-cured sausages, and to compare its effect when added at 0.5 and 3% with those of synthetic additives (sodium nitrite and ascorbic acid) and no additives (Control) in lipid and protein oxidation, the instrumental color, the sensory characteristics, and the volatile compounds. The pomace (68.7 ± 7.4 mmol Trolox g-1) was as effective as the additives at preventing lipid oxidation, resulting in values 3.2-3.8 times lower than the Control sausages. However, the pomace was not effective at decreasing the microbial counts, improving the instrumental and sensory color and the volatile compound profile, and decreasing the off-odor and off-flavor developed in the Control sausages. The lack of a detrimental effect of the pomace at 0.5% on the volatile compounds and the sensory characteristics and its benefits to delay lipid oxidation suggest that it might be useful to improve the oxidative stability. Conversely, at 3%, with a detrimental effect on some sensory characteristics and no benefits over the lower dosage, is not advisable.

Effect of Dietary Insect Meal and Grape Marc Inclusion on Flavor Volatile Compounds and Shell Color of Juvenile Abalone Haliotis iris

Almost 60% of the fish meal produced globally is used in aquaculture feeds. Fish meal production relies on finite wild-marine resources and is considered as an unsustainable ingredient. Insect meal (IM) is considered a sustainable source with high levels of protein suitable for growth promotion. Grape marc (GM) is a waste byproduct of the winery industry rich in pigments with antioxidant capacity. However, the inclusion of both ingredients can affect the flavor of the meat of abalone and the color of the shell due to different nutritional profiles. The aim of this study was to evaluate the effect of the dietary inclusion of IM and GM on the flavor volatile compounds and shell color of the juvenile Haliotis iris in a 165-days feeding trial. Abalone were offered four experimental diets with different levels of IM and GM inclusion and a commercial diet (no IM or GM). Soft bodies of abalone were used to characterize volatile compounds using solid-phase microextraction gas chromatography-mass spectrometry, and color changes were analyzed in ground powder of abalone shells using color spectrophotometry 400-700 nm (visible). The results showed 18 volatile compounds significantly different among the dietary treatments. The inclusion of IM did not significantly affect the flavor volatile compounds detected, whereas the inclusion of GM reduced volatile compounds associated with lipid-peroxidation in abalone meat. The inclusion of IM and GM did not significantly affect the lightness nor the yellowness, blueness, redness, and greenness of the ground shells. The supplementation of abalone feeds with GM can help to reduce off-flavour compounds which may extend shelf-life of raw abalone meat.

Spanish Fuet Sausages Fat-Reduced to Diminish Boar Taint: Sensory and Technological Quality

Reduced-fat cured sausages were evaluated as a strategy to reduce boar taint in entire male pork products with high levels of androstenone and skatole, both lipophilic. Three fuet-type sausages (two replicates each) were developed: the control (C) (60% lean, 33.69% fat), and two reduced-fat (60% lean 21.19% fat) products; R1, 6% inulin, 0.5% β-glucan and R2, 3% inulin, 0.5% grape skin and 1% β-glucan. All of them were prepared from entire male pork with an androstenone concentration of 6.887 µg/g and 0.520 µg/g of skatole. Significant differences (p ≤ 0.001) in the moisture content were described between the fuet R1 and the C and R2, which obtained the highest percentage. Regarding the CIELAB, the C samples had the highest L* value, while the R2 sausages were the darkest. Boar taint was reduced in both R1 and R2, with a greater reduction in R2 (p ≤ 0.000). The addition of inulin and β-glucan in fuet R1 provided a similar technological and sensory profile to C. However, both strategies provided a reduction of sexual odour, which was higher when grape skins were included. In addition, R2 gave a characteristic sausage with more odour and flavour, dark colour and overall rating than C and R1.

Effects of Dietary Red Grape Extract on the Quality Traits in Juvenile European Sea Bass (Dicentrarchus labrax L.)

Intensive fish farming is responsible for the occurrence of various stressors that negatively affect the health of cultured animals. Polyphenols are plant-derived compounds with biological activities and positive influences on the performances and immunity of fish. The aim of the present study was to evaluate the effects of dietary inclusion of a polyphenol extract obtained from Nero di Troia red grape on the quality of farmed sea bass (Dicentrarchus labrax) fillets. Three diets were tested: control (n = 90) received a conventional feed, whereas the two experimental groups (n = 90 each) received the control feed supplemented with the red grape polyphenol extract (GPE) at the concentration of 100 (GPE 100) or 200 mg/kg (GPE 200). The two GPE diets lowered (p < 0.05) the red (a *) and yellow (b *) indexes, fillet hardness, and total lipid content. Chewiness, concentration of saturated fatty acids, and the Atherogenic Index were higher (p < 0.05) in the control group; GPE diets increased (p < 0.05) the polyunsaturated fatty acids content. Furthermore, the concentration of malondialdehyde was lower (p < 0.05) in fillets of the GPE groups, thus confirming the antioxidant effect of the red grape extract and its effectiveness in preventing lipid oxidation.

Phytochemicals Derived from Agricultural Residues and Their Valuable Properties and Applications

Billions of tons of agro-industrial residues are produced worldwide. This is associated with the risk of pollution as well as management and economic problems. Simultaneously, non-edible portions of many crops are rich in bioactive compounds with valuable properties. For this reason, developing various methods for utilizing agro-industrial residues as a source of high-value by-products is very important. The main objective of the paper is a review of the newest studies on biologically active compounds included in non-edible parts of crops with the highest amount of waste generated annually in the world. The review also provides the newest data on the chemical and biological properties, as well as the potential application of phytochemicals from such waste. The review shows that, in 2020, there were above 6 billion tonnes of residues only from the most popular crops. The greatest amount is generated during sugar, oil, and flour production. All described residues contain valuable phytochemicals that exhibit antioxidant, antimicrobial and very often anti-cancer activity. Many studies show interesting applications, mainly in pharmaceuticals and food production, but also in agriculture and wastewater remediation, as well as metal and steel industries.

Grape skin flour obtained from wine processing as an antioxidant in beef burgers

The objective of this study was to determine the best level of wine making by-product meal (WBM) as a natural antioxidant to replace butylhydroxytoluene (BHT) in beef burger stored at -20 °C for up to 120 days. The treatments consisted of control (basic formulation - BF, without antioxidant); BF with BHT; and BF with WBM0.5, WBM1.0, WBM1.5, and WBM2.0, with 0.5, 1.0, 1.5 and 2.0 g WBM/100 g BF, respectively. Up to 60 days of storage, the lipid oxidation value between BHT and WBM0.5 treatments did not differ and were lower than the values presented by the other treatments. On day 90 and 120, the lipid oxidation values of treatments BHT, WBM0.5, and WBM1.0 did not differ and were lower than the values presented by WBM1.5 and WBM2.0 treatments. Burgers from all treatments with WBM inclusion had crude fiber values above 3 g/100 g. WBM1.5 and WBM2.0 treatments had the worst scores for appearance, aroma, juiciness and tenderness, in addition to the highest cooking losses. WBM can be used at up to 1 g/100 g to replace BHT in frozen beef burgers. Higher levels of WBM inclusion increased lipid oxidation and negatively affected the sensory quality of burgers.

Predicted Shelf-Life, Thermodynamic Study and Antioxidant Capacity of Breadsticks Fortified with Grape Pomace Powders

Grape pomace (GP), is the main winemaking by-product and could represent a valuable functional food ingredient being a source of bioactive compounds, like polyphenols. Polyphenols prevent many non-communicable diseases and could contrast the oxidation reaction in foods. However, the high content in polyunsaturated fatty acid, the described pro-oxidant potential action of some polyphenols and the complex interactions with other components of matrices during food processing must be considered. Indeed, all these factors could promote oxidative reactions and require focused and specific assay. The aims of this study were to evaluate the effects of GP powder (GPP) addition (at 0%, 5% and 10% concentrations) in breadsticks formulations both on the antioxidant activity at room temperature during storage and on the shelf-life by the OXITEST predictive approach. GPP fortification increased the total polyphenols content and the antioxidant activities of breadsticks. FRAP reduced during the first two days of storage at room temperature, TPC increased during the 75 days, while ABTS showed a slight progressive decrease. However, GP negatively influenced OXITEST estimated shelf-life of breadsticks, incrementing the oxidation rate. In conclusion, even if GP fortification of breadsticks could improve the nutritional value of the products, the increased commercial perishability represents a drawback that must be considered.

Effect of grape pomace from red cultivar 'Nero d'Avola' on the microbiological, physicochemical, phenolic profile and sensory aspects of ovine Vastedda-like stretched cheese

AIMS

The purpose of this study was to functionalize an ovine stretched cheese belonging to 'Vastedda' typology with red grape pomace powder (GPP) of Nero d'Avola cultivar and to characterize the microbiological, physicochemical, phenolic profile and sensory characteristics of the final cheeses.

METHODS AND RESULTS

Before cheeses production, GPP was characterized for its microbiological profile, antibacterial activity and polyphenolic content. No colonies of bacteria and yeasts were detected in the GPP. GPP showed a large inhibition spectrum against spoilage and pathogenic bacteria. Three classes of polyphenolic compounds belonging to flavan-3-ols, flavonol and phenolic acids were identified. Two cheeses [0 and 1% (w w^-1 ) of GPP] were produced with pasteurized ewe's milk and commercial starter cultures. Plate counts and randomly amplified polymorphic DNA analysis demonstrated the ability of the starter strains to drive the fermentation process in the presence of GPP. GPP enrichment resulted in an increase of protein, phenolic compounds, sensory traits and reduced fat.

CONCLUSIONS

GPP addition to cheese represents an optimal strategy for the valorization of winemaking by-products and to obtain polyphenol-enriched cheese.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study allowed to achieve an ovine cheese with specific physicochemical, nutraceutical and sensorial characteristics able to enlarge the functional dairy product portfolio.

Tailored Functionalization of Natural Phenols to Improve Biological Activity

Phenols are widespread in nature, being the major components of several plants and essential oils. Natural phenols' anti-microbial, anti-bacterial, anti-oxidant, pharmacological and nutritional properties are, nowadays, well established. Hence, given their peculiar biological role, numerous studies are currently ongoing to overcome their limitations, as well as to enhance their activity. In this review, the functionalization of selected natural phenols is critically examined, mainly highlighting their improved bioactivity after the proper chemical transformations. In particular, functionalization of the most abundant naturally occurring monophenols, diphenols, lipidic phenols, phenolic acids, polyphenols and curcumin derivatives is explored.

Sustainable sources for antioxidant and antimicrobial compounds used in meat and seafood products

The contribution of food in promotion of health has become of most importance. The challenges that lie before the global food supply chain, such as climate changes, food contamination, and antimicrobial resistance may compromise food safety at international scale. Compounds with strong antimicrobial and antioxidant activity can be extracted from different natural and sustainable sources and may contribute to extend the shelf life of meat and seafood products, enhance food safety and enrich foods with additional biologically active and functional ingredients. This chapter describes the use of bioprotective cultures, essential oils, plant extracts, seaweed extracts and grape pomace compounds in production of value-added meat and seafood products with improved shelf life and safety, following the requests from the market and consumers.

Monitoring Commercial Starter Culture Development in Presence of Red Grape Pomace Powder to Produce Polyphenol-Enriched Fresh Ovine Cheeses at Industrial Scale Level

Red grape Nero d’Avola cultivar grape pomace powder (GPP) was applied during fresh ovine cheese production in order to increase polyphenol content. Before cheeses were produced, the bacteria of a freeze-dried commercial starter culture were isolated and tested in vitro against GPP. Two dominant strains, both resistant to GPP, were identified. Thestarter culture was inoculated in pasteurized ewe’s milk and the curd was divided into two bulks, one added with 1% (w/w) GPP and another one GPP-free. GPP did not influence the starter culture development, since lactic acid bacteria (LAB) counts were 109 CFU/g in both cheeses at 30 d. To exclude the interference of indigenous LAB, the pasteurized milk was analyzed, and several colonies of presumptive LAB were isolated, purified and typed. Four strains were allotted into Enterococcus and Lacticaseibacillus genera. The direct comparison of the polymorphic profiles of cheese bacteria evidenced the dominance of the starter culture over milk LAB. The addition of GPP increased cheese total phenolic compounds by 0.42 g GAE/kg. Sensory evaluation indicated that GPP-enriched cheese was well appreciated by the judges, providing evidence that GPP is a suitable substrate to increase the availability of total phenolic content in fresh ovine cheese.

Impact of Grape Pomace Powder on the Phenolic Bioaccessibility and on In Vitro Starch Digestibility of Wheat Based Bread

Breads were prepared by substituting common wheat flour with 0 (GP0), 5 (GP5) and 10 (GP10) g/100 g (w/w) of grape pomace powder (GPP) and were analyzed for the phenolic profile bioaccessibility as well as the in vitro starch digestion during simulated digestion. The free and bound phenolic composition of native GPP and resulting breads were profiled using ultra-high-performance chromatography-quadrupole-time-of-flight (UHPLC-QTOF). The raw GPP was characterized by 190 polyphenols with the anthocyanins representing the most abundant class, accounting for 11.60 mg/g of cyanidin equivalents. Regarding the fortified bread, the greatest (p < 0.05) content in phenolic compounds was recorded for the GP10 sample (considering both bound and free fractions) being 127.76 mg/100 g dry matter (DM), followed by the GP5 (106.96 mg/100 g DM), and GP0 (63.76 mg/100 g DM). The use of GPP determined an increase of anthocyanins (considered the markers of the GPP inclusion), recording 20.98 mg/100 g DM in GP5 and 35.82 mg/100 g DM in GP10. The bioaccessibility of anthocyanins increased in both GP5 and GP10 breads when moving from the gastric to the small intestine in vitro digestion phase with an average value of 24%. Both the starch hydrolysis and the predicted glycemic index decreased with the progressive inclusion of GPP in bread. Present findings showed that GPP in bread could promote an antioxidant environment in the digestive tract and influence the in vitro starch digestion.

The Use of Winery by-Products to Enhance the Functional Aspects of the Fresh Ovine "Primosale" Cheese

Fresh ovine "primosale" cheese was processed with the addition of grape pomace powder (GPP). Cheese making was performed using pasteurized ewes' milk and four selected Lactococcus lactis strains (Mise36, Mise94, Mise169 and Mise190) inoculated individually. For each strain the control cheese (CCP) was not added with GPP, while the experimental cheese (ECP) was enriched with 1% (w/w) GPP. GPP did not influence the starter development that reached levels of 10⁹ CFU/g in all final cheeses. The comparison of the bacterial isolates by randomly amplified polymorphic DNA (RAPD)-PCR showed the dominance of the added strains over indigenous milk bacteria resistant to pasteurization. GPP addition reduced fat content and determined an increase of protein and of secondary lipid oxidation. Sensory tests indicated that cheeses CCP94 and ECP94, produced with the strain Mise94, reached the best appreciation scores. Following in vitro simulated human digestion, bioaccessible fraction of ECP94 showed antioxidant capacity, evaluated as radical scavenging activity and inhibition of membrane lipid oxidation, significantly higher than that from CCP94, with promising increase in functional properties. Thus, the main hypothesis was accepted since the functional aspects of the final cheeses improved, confirming that GPP is relevant for sustainable nutrition by using winemaking by-products.

Effect on the Antioxidant, Lipoperoxyl Radical Scavenger Capacity, Nutritional, Sensory and Microbiological Traits of an Ovine Stretched Cheese Produced with Grape Pomace Powder Addition

An innovative ovine cheese enriched with red grape pomace powder (GPP) was produced to improve the functional properties of Vastedda cheese typology. Vastedda cheese making was performed adding GPP and four selected Lactococcus lactis strains (Mise36, Mise94, Mise169 and Mise190). For each strain, 40 L of pasteurized ewe's milk was divided into two aliquots representing control and experimental trials. Control cheese (CC) production did not contain GPP, while the experimental cheese (EC) production was enriched with 1% (w/w) GPP. GPP did not slow down starter development and acid generation. Plate counts and randomly amplified polymorphic DNA (RAPD)-PCR analysis confirmed the dominance of the starters in all trials. The evolution of the physicochemical parameters showed that EC productions were characterized by lower fat content, higher protein content, and higher values of secondary lipid oxidation. Sensory evaluation indicated that the cheeses produced with the strain Mise94 were those more appreciated by the judges. Thus, the last cheeses were investigated for some functional aspects: GPP enrichment significantly increased antioxidant activity and lipoperoxyl radical scavenger capacity, confirming that grape polyphenol inclusion in cheese represents an optimal strategy for the valorization of ovine cheeses as well as winemaking industry by-products.

Wheat Bread Fortification by Grape Pomace Powder: Nutritional, Technological, Antioxidant, and Sensory Properties

Grape pomace powder (GPP), a by-product from the winemaking process, was used to substitute flour for wheat bread fortification within 0, 5, and 10 g/100 g. Rheological properties of control and fortified doughs, along with physicochemical and nutritional characteristics, antioxidant activity, and the sensory analysis of the obtained bread were considered. The GPP addition influenced the doughs' rheological properties by generating more tenacious and less extensible products. Concerning bread, pH values and volume of fortified products decreased as the GPP inclusion level increased in the recipe. Total phenolic compounds and the antioxidant capacity of bread samples, evaluated by FRAP (ferric reducing ability of plasma) and ABTS (2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)) assays, increased with GPP addition. Moreover, the GPP inclusion level raised the total dietary fiber content of bread. Regarding sensory evaluation, GPP fortification had a major impact on the acidity, the global flavor, the astringency, and the wine smell of bread samples without affecting the overall bread acceptability. The current results suggest that GPP could be an attractive ingredient used to obtain fortified bread, as it is a source of fiber and polyphenols with potentially positive effects on human health.

A Systemic Design Approach Applied to Rice and Wine Value Chains. The Case of the InnovaEcoFood Project in Piedmont (Italy)

Attention to food waste is an increasingly growing phenomenon today, especially in the context of a circular economy. The InnovaEcoFood project investigates the use of by-products of the Piedmontese rice and wine production chains to valorize their untapped potential in the food sector by applying the Systemic Design approach. We collected, systematized, and visualized a range of solutions for exploiting these by-products, starting from an in-depth literature review on the two value chains. With the support of a consortium of partners from both multidisciplinary industrial and academic sectors, it was possible to validate the links that have been generated. Eventually, the project created food products that integrated these outputs as ingredients (like flour and butter) because they have antioxidant properties and are rich in proteins. InnovaEcoFood has successfully tested how value could be created from waste. Moreover, using rice hull, marc flour, and bran lipid (butter) is of immediate technical and economic feasibility. It could be considered a viable way that deserves further experimentation.

Fat Replacement by Vegetal Fibres to Improve the Quality of Sausages Elaborated with Non-Castrated Male Pork

Simple Summary

Traditionally, male pigs were castrated without anaesthesia or pain relief before they reached 7 days of age to avoid the production of an undesirable odour and flavour in their meat, termed “boar taint.” In recent years, to improve animal welfare according to European recommendations, farmers have generally abandoned this practice, increasing the supply of non-castrated male pork in the market. Based on this, alternatives are required to improve the quality of meat and meat products derived from these animals, as these products also possess different texture characteristics that make the meat harder and less juicy due to the presence of less fat. Recently, health has become more important to consumers, and reducing the fat content in non-castrated male pig products by replacing it with vegetable fibre has been shown to represent a good strategy for masking and improving texture.

Abstract

Based on the need to find alternatives for the use of meat from non-castrated male pigs that contains high levels of androstenone and skatole, the production of meat products (raw and Frankfurt sausages) with reduced fat content was proposed, as these compounds are lipophilic. For this purpose, three batches of each product (total six) were produced. These included a control batch (1); normal fat content and two fat-reduced batches, where (2) fat was replaced with inulin and β-glucan, or (3) fat was replaced with inulin and β-glucan in addition to a skin grape by-product. These groups used meat from non-castrated male pigs that contained 6.25 µg/g androstenone and 0.4451 µg/g skatole. In general, fat-reduced sausages exhibited less brightness than did the controls. The texture results in Frankfurt were similar to those of the control, while Spanish sausage supplemented with grape skin exhibited reduced hardness. Both strategies resulted in a reduction in boar taint, and this reduction was up to 87.3% in raw sausages with grape by-products. Fat reduction could provide an interesting strategy to allow for the use of tainted meat from non-castrated male pigs.

Monitoring the antioxidant activity of an eco-friendly processed grape pomace along the storage

The aims of this research are to compare and to monitor two conditions for preserving the total phenolic content (TPC) and the antioxidant activity (AOA) of grape pomace (GP) processed as powder and its corresponding extract at room and freezing temperature, respectively. The highest TPC and AOA were obtained in the GP extracted in a ratio 1:10 (w/v) with ethanol at 50% for 45 min at 50 °C. After 9 months of room temperature (RT) storage, the GP powder obtained a significantly higher AOA than the initial condition and the extract frozen-stored the same time.

New insights into red plant pigments: more than just natural colorants

Pigments make nature both colorful and attractive. Humans have always incorporated the natural pigments of fruits, vegetables and spices into their dietary requirements. Naturally occurring red pigments in plants are carotenoids, anthocyanins and betacyanins. Natural pigments, apart from colour, provide added properties and are therefore considered to be bioactive constituents. Red natural colorants are one of the most widely used in the food industry. The interest in these pigments lies in the enhancement of the healthy effects of the diet. In this context, attention is given to carotenoids, anthocyanins and betacyanins, with emphasis on the basic chemical and biochemical attributes and wide-ranging health-promoting benefits of these pigments. Thus, in this review, we systematically present the advantages and limitations of these natural pigments as food colorants in relation to their physico-chemical properties, reactivity and bioactivity.

Study of the phenolic profile of a grape pomace powder and its impact on delaying corn oil oxidation

The grape pomace, the main by-product from the winemaking industry, contains many bioactive substances that must be valorized. The aim of this study was to assess the total phenolic content (TPC), phenolics profile by using HPLC and the antioxidant activity (AOA). The results showed a TPC of 38.86 ± 5.22 g gallic acid equivalent (GAE)/kg while an AOA of 247.84 ± 18.65 µmol Trolox equivalent (TE)/g. Epicatechins were the most representative phenolic compound, according to the HPLC analysis. Then, the grape pomace powder (GPP) was tested in the Rancimat equipment as a natural antioxidant for delaying the corn oil oxidation. Results showed statistically significant differences between the corn oil treated with GP and the control, so the GPP could be a promising natural antioxidant to tackle the oxidation vulnerability of corn oil.

Effects of Supplementing Grape Pomace to Broilers Fed Polyunsaturated Fatty Acids Enriched Diets on Meat Quality

Simple Summary

Chicken meat and its products are among the first-choice foods in most countries, due to the health benefits they provide and the relatively low price. However, polyunsaturated fatty acids (PUFA) are highly susceptible to peroxidation, affecting nutritional, sensory characteristics and meat shelf life. A reasonable way and a good tactic to delay their lipid peroxidation would be using a natural antioxidant in feed formulation. Grape pomace (GP) is an agro-industrial by-product with high nutritional value as it is a rich source of polyphenols. The supplementation of broiler diets with grape pomace indicated an intensified color, improved texture and a decrease of lipid peroxidation parameters of broilers’ meat that had been fed with PUFA enriched diets.

Abstract

The effects of using grape pomace as natural antioxidant in polyunsaturated fatty acids enriched broiler diets (4% flaxseed meal) on color, texture and lipid peroxidation of meat were evaluated. The 4-week feeding trial was conducted on 200, Cobb 500 broilers, assigned to 5 groups and housed in an experimental hall with floored pens. Compared to the control group, the diet for the experimental groups included 3% or 6% of two grape pomace varieties, white and red. Diet formulation enrichment with red grape pomace influenced the meat color parameters, underlining an accentuated total color difference (ΔE) for both breast and thigh as compared to the control. The dietary supplementation with grape pomace led to the increase of meat hardness regardless of the amount and variety added. The grape pomace inclusion in broiler diets positively influenced meat color and texture. Regarding the lipid oxidation parameters, there was a decrease of the value of thiobarbituric acid-reactive substances (TBARS) in thigh meat in all experimental groups. Additionally, significant differences were highlighted for breast in 3% white grape pomace and 6% red grape pomace supplemented groups when compared to the control group. In conclusion, the supplementation of broiler diets enriched in PUFA with grape pomace improved meat color and texture, which are essential parameters for consumer’s choice. Also, the grape pomace supplementation indicated an improvement of thigh meat oxidative stability, especially regarding the TBARS value.

The life and times of yeasts in traditional food fermentations

Yeasts are eukaryotic microorganisms which have a long history in the biotechnology of food production, as they have been used since centuries in bread-making or in the production of alcoholic beverages such as wines or beers. Relative to this importance, a lot of research has been devoted to the study of yeasts involved in making these important products. The role of yeasts in other fermentations in association with other microorganisms - mainly lactic acid bacteria - has been relatively less studied, and often it is not clear if yeasts occurring in such fermentations are contaminants with no role in the fermentation, spoilage microorganisms or whether they actually serve a technological or functional purpose. Some knowledge is available for yeasts used as starter cultures in fermented raw sausages or in the production of acid curd cheeses. This review aimed to summarize the current knowledge on the taxonomy, the presence and potential functional or technological roles of yeasts in traditional fermented plant, dairy, fish and meat fermentations.

Bioactive potential of fruit and vegetable wastes

Fruits and vegetables are essential for human nutrition, delivering a substantial proportion of vitamins, minerals, and fibers in our daily diet. Unfortunately, half the fruits and vegetables produced worldwide end up as wastes, generating environmental issues caused mainly by microbial degradation. Most wastes are generated by industrial processing, the so-called by-products. These by-products still contain many bioactive compounds post-processing, such as macronutrients (proteins and carbohydrates) and phytochemicals (polyphenols and carotenoids). Recently, the recovery of these bioactive compounds from industry by-products has received significant attention, mainly due to their possible health benefits for humans. This chapter focuses on the bioactive potential of fruit and vegetable by-products with possible applications in the food industry (functional foods) and in the health sector (nutraceuticals).