White grape pomace as a source of dietary fibre and polyphenols and its effect on physical and nutraceutical characteristics of wheat biscuits

The high-value and sustainable utilization of grape pomace: A review

A large portion of global grape production has been utilized for wine production, accompanied by tremendous pressure to dispose grape pomace. To achieve circular economy, the high-value recycling of grape pomace must be considered. The social level barriers to circular economy promotion are also important constraints, like the acceptability of upcycled products. The main components of grape pomace and their utilization are summarized, and critical reviews of green extraction methods analyzed the key points of grape pomace recycling process to achieve the goal of sustainability in the production process, culminating in discussions of the factors affecting the acceptability of upcycled products. Grape pomace bioactive substances have higher added value. To realize its green extraction, various emerging technologies need to be made a comprehensive choice. Nevertheless, the acceptability of upcycled products is influenced by personal, context and product factors, optimizing them is essential to remove the constraints of circular economy development.

Transforming plant-based waste and by-products into valuable products using various "Food Industry 4.0" enabling technologies: A literature review

The last several years have seen unprecedented strain on food systems as a result of pandemics, climate change, population growth, and urbanization. Thus, academic and scientific communities now view global food security as a critical issue. However, food loss and waste are a major challenge when adopting food security and sustainability strategies, since a large proportion of food is lost or wasted along the food supply chain. In order to use resources efficiently and enhance food security and sustainability, food waste and by-products must be reduced and properly valorized. Plant-based food production generates various by-products which are generally rich in nutrients and bioactive compounds. Emerging technologies have been effectively employed to extract these valuable compounds with health benefits. Recently, Industry 4.0 technologies such as artificial intelligence, the Internet of Things, blockchain, robotics, smart sensors, 3D printing, and digital twins have a great deal of potential for waste reduction and by-products valorization in food industry. Reducing food waste not only benefits the environment, but also reduces greenhouse gas emissions and thus contributes to sustainable resource management. This review provides up-to-date information on the potential of Industry 4.0 for converting plant-based waste and by-products into valuable products. Recent studies showed that innovations in Industry 4.0 provide attractive opportunities to increase the effectiveness of manufacturing operations and improve food quality, safety and traceability. By leveraging Food Industry 4.0, companies can transform plant-based waste and by-products into valuable products and contribute to a more sustainable and efficient food production system.

Consumers' familiarity with wine increased their acceptance of pasta sauce containing grape pomace

Grape pomace (GP) is a waste product of the winemaking process and has been proposed as a nutritionally beneficial ingredient, as it contains phenolic compounds, dietary fiber, and antioxidant activity. It can be a polarizing ingredient due to its flavor components. Familiarity has been found to influence consumers' preferences and sensory perception of food. A sensory test was conducted to evaluate the acceptance, sensory perception, and emotional response to pasta sauces containing GP (3% [3GP], 6% [6GP], 9% [9GP] by volume and control without GP addition). The sensory trials included wine consumers (n = 44) and nonconsumers of wine (n = 58) to determine how consumers' familiarity with the flavor properties of GP influenced their perception of the pasta sauce. Overall, the addition of GP decreased the liking scores of the GP-containing sauces, but the wine consumers' hedonic scores for the control, 3GP, and 9GP were significantly higher than the nonconsumers. Both consumer groups identified that the samples with a higher amount of GP addition were associated with sour, bitter, astringency, grainy, and gritty attributes. However, the wine consumers used more positive emotions to describe their emotional response to the GP-containing samples. The study identified that GP led to off-flavors and textures in the pasta sauces. PRACTICAL APPLICATION: GP is currently a waste product, but it has many nutritional benefits. Consumers are increasingly looking for nutritional benefits from their food. When incorporated into pasta sauces, GP decreased the acceptance of the pasta sauce and negatively impacted the flavor and texture. Familiarity has been found to impact consumer acceptance, and wine consumers had a more positive emotional response and higher hedonic scores in response to the GP-containing pasta sauce than nonconsumers of wine.

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.

Effect of goji berry incorporation on the texture, physicochemical, and sensory properties of wheat bread

The regular intake of Lycium barbarum (goji berry) is supposed to play an important role in the promotion of human health. Regarding, its incorporation into staple foods, including bread, seems to be effective. However, it requires the evaluation of dough behavior and final product quality. This study investigated the effect of goji berry incorporation at levels of 10, 15, 20, 25, and 30% ww-1 on the textural, physicochemical, and sensory properties of wheat bread. Results indicated a significant enhancement of water absorption and gelatinization temperature in composite flour via the inclusion of goji berry powder (p < 0.05). Using goji berry powder up to 20% ww-1 has shown to obtain the structure able to restore gases through the baking process and provide enhancement in a specific volume at about 10%. Alongside, the hardness of composite bread decreased, and the optimal hardness was observed at formulations containing 20% w/w goji berry powder with a value equal to 1199.95 ± 0.05 g, which is supposed to be induced by the higher specific volume and lower moisture content of bread samples. Moreover, color and sensory perception have been found to be significantly changed by goji berry substitution. Goji berry substitution up to 20% ww-1 is found to be preferred by the consumer, and a drop in overall acceptability was observed at its higher inclusion. The technological characteristic changes induced by goji berry incorporation are induced by its gluten dilution impact. However, the gel-like structure formed by the high fiber content of goji berries compensates for this adverse impact up to 20% w/w substitution level.

Dietary fiber-and antioxidant-enriched cookies prepared by using jackfruit rind powder and ascorbic acid

The demand for dietary fiber-rich cookies has increased due to customer awareness about the importance of dietary fiber in human health. In addition, the urge of creating food sustainability has led to the need to reuse food by-products. In this study, dietary fiber-rich cookies were developed by incorporating jackfruit rind (JFR) powder, a by-product of jackfruit processing, as a replacement for wheat flour. The study aimed to evaluate the effects of different replacement levels (0, 10, 20, 30 and 40 %) on the proximate composition, physical properties and overall sensory acceptability of the cookies. While JFR powder addition led to a significant increase in dietary fiber and antioxidant (phenolics, flavonoids and carotenoids) contents of the cookies, the physical properties and overall acceptability of the cookies were adversely affected. The total dietary fiber and total phenolic content of the cookies at 40 % JFR powder addition were 5 and 5.5 times as much as those of the cookies with 0 % JFR powder addition. To address the adverse effects of JFR addition, various concentrations of ascorbic acid (AA), a dough improver agent, were added to the blended dough, and their effects on dough and cookie properties were investigated. With the addition of ascorbic acid at concentrations of 200 mg ascorbic acid per 100 g of the blend flour, the cookie density and cookie hardness reduced by 16 % and 31 %, respectively while the overall acceptability increased by 37 % compared to those of the cookies without ascorbic acid addition.

Phenolic, Nutritional and Sensory Characteristics of Bakery Foods Formulated with Grape Pomace

The potentiality of cv. Malbec grape pomace (GP) as a functional ingredient in the formulation of bakery foods (muffins, biscuits and cereal bars) was studied. The effect of GP addition on the phenolic compounds (PCs) composition, nutritional and sensory properties were evaluated. The addition of GP increased the content of dietary fiber, proteins, ash, total phenolic content (TPC), antiradical capacity (AC), anthocyanins and non-anthocyanin PCs while decreasing the carbohydrates content. The main PCs given by the GP to supplemented foods were quercetin-3-O-glucoside, rutin, caffeic acid, syringic acid and (+)-catechin. For anthocyanins, the acylated derivatives were more stable to heat treatment (baking) in food processing which was evidenced by a higher proportion of these PCs compounds when compared to the same derivatives quantified in GP. In general, when the TPC or individual concentrations of PCs were analyzed in a nutritional or functional context, one portion of the supplemented foods showed levels high enough to satisfy the recommended dose per day of these bioactive compounds. Additionally, the foods were well received by consumers during the sensory evaluation and supplemented biscuits received the highest acceptability. This study demonstrated that GP could be a viable functional ingredient in bakery foods to incorporate components like PCs and dietary fiber into traditional consumers' diets.

Grape Pomace-Advances in Its Bioactivity, Health Benefits, and Food Applications

From a circular economy perspective, the appropriate management and valorization of winery wastes and by-products are crucial for sustainable development. Nowadays, grape pomace (GP) has attracted increasing interest within the food field due to its valuable content, comprising nutritional and bioactive compounds (e.g., polyphenols, organic and fatty acids, vitamins, etc.). Particularly, GP polyphenols have been recognized as exhibiting technological and health-promoting effects in different food and biological systems. Hence, GP valorization is a step toward offering new functional foods and contributing to solving waste management problems in the wine industry. On this basis, the use of GP as a food additive/ingredient in the development of novel products with technological and functional advantages has recently been proposed. In this review, we summarize the current knowledge on the bioactivity and health-promoting effects of polyphenolic-rich extracts from GP samples. Advances in GP incorporation into food formulations (enhancement of physicochemical, sensory, and nutritional quality) and information supporting the intellectual property related to GP potential applications in the food industry are also discussed.

Application of White-Wine-Pomace-Derived Ingredients in Extending Storage Stability of Fresh Pork Burgers

White wine pomace, a by-product from winemaking, was stabilized after the application of thermal blanching (with the aim of deactivating the polyphenoloxidase enzyme), milling, and processing by hydrostatic high-pressure treatment (with the aim of reducing initial microbial loads while preserving phenolic compounds content). The valorized pomace (VP) ingredient was added at different proportions to pork burgers (0.5%, 1%, and 3% w/w) to improve their preservation, and the effect was compared to those produced by sulfites and with a control (without sulfites or VP). Burgers were vacuum-packed and refrigerated for 7 days. Microbiological, color, oxidation, and sensory parameters were analyzed. Neither sulfites nor VP reduced the microbial development of most microorganism groups evaluated (p > 0.05); however, both prevented coliform growth during storage (p < 0.01). The use of sulfites prevented the discoloration of burgers during storage, while VP had no effect (p < 0.001). On the contrary, VP limited lipid and protein oxidation development during storage (p > 0.05), while sulfites had no effect. Therefore, the use of VP from white wine production could have an antioxidant effect but a limited antimicrobial or color-protective effect for the preservation of pork burgers.

Effect of Bioactive Compounds from Pumpkin Powder on the Quality and Textural Properties of Shortbread Cookies

The problem of food with functional ingredients, characterized by low energy intake and a variety of phytonutrients with biological activity, is one of the concerns of the population. The objectives of this study were to investigate the effect of pumpkin powder and its bioactive components on the quality, color and textural properties of shortbread cookies. In the drying process of pumpkin powder (Cucurbita moschata) at 60 ± 2 °C, the physicochemical parameters did not change significantly in relation to fresh pulp. The chromatic parameters L*, a* and b* showed that the pumpkin powder was brighter than the pulp, with a greater presence of yellow pigments. Pumpkin powder presented a rich source of bioactive compounds (polyphenols flavonoids, carotenoids) with an antioxidant potential of 161.52 mmol TE/100 g DW and 558.71 mg GAE/100 g DW. Antimicrobial activity against Gram-positive (Staphylococcus aureus, Bacillus cereus), Gram-negative (Escherichia coli, Salmonella Abony and Pseudomonas aeruginosa) bacteria and high antifungal activity against Candida albicans were attested. The sensory, physicochemical, texture parameters and color indicators of shortbread cookies with yellow pumpkin powder (YPP) added in a proportion of 5-20% were analyzed. The optimal score was given to the sample of 15% YPP. The use of 15-20% YPP contributed to improved consistency due to the formation of complexes between starch and protein.

On the Valorization of Arbutus unedo L. Pomace: Polyphenol Extraction and Development of Novel Functional Cookies

The fruits of Arbutus unedo L. have a crimson colour and are enriched with remarkable concentrations of bioactive compounds such as anthocyanins and polyphenols. These fruits are commonly used in the production of a Portuguese Protected Geographical Indication distillate called "Aguardente de Medronho". During this process, a solid pomace is generated and presently discarded without valuable applications. In this work, two strategies have been developed for the valorisation of A. unedo pomace. The first approach considers the extraction of polyphenols from this by-product through the optimization of an ultrasound-assisted method using a Box-Behnken design coupled with response surface methodology. The results indicate that the temperature and the percentage of methanol, along with their interaction, significantly influence the total concentration of polyphenols and the antioxidant activity of the extracts obtained. The optimal conditions identified consider the extraction of 0.5 g of sample with 20 mL of a solvent containing 74% MeOH (aq), at a pH of 4.8, maintained at 70 °C for 15 min. On the other hand, the second valorisation strategy considered the use of A. unedo pomace in the development of functional cookies. The incorporation of 15-20% pomace in the cookie formulation was well-received by consumers. This incorporation results in an intake of ca. 6.55 mg of polyphenols per gram of cookie consumed, accompanied by an antioxidant activity of 4.54 mg Trolox equivalents per gram of cookie consumed. Overall, these results encourage the employment of A. unedo pomace either as a reliable source of extracts enriched in polyphenols or as a nutraceutical active ingredient in functional cookies, thereby positively impacting human health.

Strategies to Formulate Value-Added Pastry Products from Composite Flours Based on Spelt Flour and Grape Pomace Powder

In recent years, sustainability has promoted new research to develop reformulation strategies for value-added food products by exploiting grape pomace. Grape pomace powder (GP) was used to substitute spelt flour (SF) at 0, 5, 10, 15, 20 and 25% to obtain three types of fortified pastry products: biscuits and cakes involving a chemical leavening agent, and rolls leavened by yeast. Proximate composition, total phenolic content (TPC), total flavonoids content (TFC), 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity and ferric-reducing antioxidant power (FRAP) along with physical characteristics and sensory analysis of the enriched products were considered. The retention rate of the functional attributes of formulations in response to baking was also evaluated. Significant improvements in TPC, TFC and both antioxidant tests were achieved in the fortified products by the incremental incorporation of GP. With a substitution of 25% SF by GP, the following increases were recorded in biscuits, cakes and rolls over the control samples: 7.198-, 7.733- and 8.117-fold for TPC; 8.414-, 7.000- and 8.661-fold for TFC; 16.334-, 17.915- and 18.659-fold for FRAP and 16.384-, 17.908- and 18.775-fold for DPPH. The retention rates of TPC, TFC, FRAP and DPPH relative to the corresponding dough were 41-63%, 37-65%, 48-70% and 45-70%. The formulas leavened by yeast revealed higher functionality than those produced with a chemical raising agent. With the increase in GP, the elasticity and porosity gradually decreased for cakes and rolls, while the spread ratio of biscuits increased. Regarding sensory evaluation, all formulations with incorporated GP up to 10% were rated at an extremely pleasant acceptability level. The solutions derived from this study have great practical applicability for the development of new pastry formulations with improved functionality from GP valorisation.

Effect of Grape Pomace Flour in Savory Crackers: Technological, Nutritional and Sensory Properties

The wine industry generates large amounts of by-products that are usually destined as waste. Grape pomace is the residue of the winemaking process and is rich in compounds with functional properties, such as dietary fiber and phenolic compounds. The aim of this research was to study the influence of white and red grape pomace flour (GPF) addition in the enhancement of functional properties of savory crackers. Different levels of incorporation were tested (5%, 10% and 15% (w/w)). Analysis of physical properties, nutritional composition and sensory acceptability were conducted to evaluate the effect of GPF incorporation. GPF cracker stability throughout a four-week period was achieved with regard to firmness and color. These products presented distinctive and appealing colors, ranging from a violet (GPF of Touriga Nacional variety) to a brown hue (GPF of Arinto variety). Concerning nutritional composition, both crackers incorporated with 10% GPF of Arinto or Touriga Nacional varieties could be considered “high in fiber”, as per the Regulation (EC) No. 1924/2006, suggesting a functional food. GPF crackers demonstrated an overall great acceptance of this kind of innovative foods, with the majority indicating that they would certainly/probably buy them. Moreover, the cracker with 10% Arinto GPF achieved the most balanced and overall preference.

Physicochemical Characterization and Evaluation of Gastrointestinal In Vitro Behavior of Alginate-Based Microbeads with Encapsulated Grape Pomace Extracts

Grape pomace is a byproduct of wineries and a rich source of phenolic compounds that can exert multiple pharmacological effects when consumed and enter the intestine where they can then be absorbed. Phenolic compounds are susceptible to degradation and interaction with other food constituents during digestion, and encapsulation may be a useful technique for protecting phenolic bioactivity and controlling its release. Therefore, the behavior of phenolic-rich grape pomace extracts encapsulated by the ionic gelation method, using a natural coating (sodium alginate, gum arabic, gelatin, and chitosan), was observed during simulated digestion in vitro. The best encapsulation efficiency (69.27%) was obtained with alginate hydrogels. The physicochemical properties of the microbeads were influenced by the coatings used. Scanning electron microscopy showed that drying had the least effect on the surface area of the chitosan-coated microbeads. A structural analysis showed that the structure of the extract changed from crystalline to amorphous after encapsulation. The phenolic compounds were released from the microbeads by Fickian diffusion, which is best described by the Korsmeyer-Peppas model among the four models tested. The obtained results can be used as a predictive tool for the preparation of microbeads containing natural bioactive compounds that could be useful for the development of food supplements.

Study on nanocellulose isolated from waste chilli stems processing as dietary fiber in biscuits

In order to expand the high added value of waste chilli stems and the recycling of green resources, cellulose in chilli stems was extracted by nitric acid-ethanol method, and nanocellulose was prepared by sulfuric acid hydrolysis method. The results showed that the cellulose content was between 15% and 34.5%. Under the optimum experimental conditions of 60% sulfuric acid concentration, 60°C reaction temperature and 120 min reaction time, the average yield of nanocellulose was 36.42% ±1.36%. Prepared cellulose and nanocellulose had been characterized using scanning electron microscopy, fourier-transform infrared, and x-ray diffraction analysis. The research indicated that the biscuits with acceptable overall quality could be prepared by using the dosage of nanocellulose (7%), and the corresponding biscuits had regular appearance and relatively smooth surface. The total dietary fiber content was positively correlated with different nanocellulose content. Through mice experiments, it was found that the consumption of biscuits containing nanocellulose could significantly reduce the food intake of mice and inhibit the weight growth of mice. Therefore, the research showed that whole wheat biscuits with nanocellulose could be regarded as food rich in dietary fiber. These results provided a basis for exploring the green resource recycling of chilli stems in food processing.

The α-Amylase and α-Glucosidase Inhibition Capacity of Grape Pomace: A Review

The concept of functional foods is gaining more importance due to its role in maintaining a healthy status and preventing some metabolic diseases. The control of diabetes, in particular type-2 (T2DM), could be considered a big challenge since it involves other factors such as eating habits. From the pharmacological point of view, inhibiting digestive enzymes, such as α-amylase and α-glucosidase, is one of the mechanisms mainly used by synthetic drugs to control this disease; however, several side effects are described. For that reason, using bioactive compounds may appear as an alternative without presenting the complications synthetic drugs available on the market have. The winemaking industry generates tons of waste annually, and grape pomace (GP) is the most important. GP is recognized for its nutritional value and as a source of bioactive compounds that are helpful for human health. This review highlights the importance of GP as a possible source of α-amylase and α-glucosidase inhibitors. Also, it is emphasized the components involved in this bioactivity and the possible interactions among them. Especially, some phenolic compounds and fiber of GP are the main ones responsible for interfering with the human digestive enzymes. Preliminary studies in vitro confirmed this bioactivity; however, further information is required to allow the specific use of GP as a functional ingredient inside the market of products recommended for people with diabetes.

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Potential Prebiotic Effect of Cava Lees: Changes in Gut Microbiota

Lees are a winery by-product with a fiber-rich composition that could have a potential prebiotic effect on gut microbiota. Prebiotics cannot be digested by humans but can be used by bacteria found in the large intestine. To evaluate the potential prebiotic effect of lees, they were administered to Wistar rats for 14 days. Feces were collected daily, and DNA was extracted and analyzed by shot gun sequencing. The supplementation with lees did not affect weight, food intake, or water consumption of the studied rats. It was found that lees promoted the increase of relative abundance of probiotic bacteria belonging to the Lactobacillaceae family, as well as other potentially probiotic species such as Blautia hansenii, Roseburia intestinalis, and Ruminococcus obeum. Moreover, lees supplementation also reduced the abundance of certain pathogenic bacteria. In conclusion, lees can improve the presence of beneficial bacteria in the gastrointestinal tract and can be re-valorized as a new ingredient in food formulation.

The Wine Industry By-Products: Applications for Food Industry and Health Benefits

Each year, 20 million tons of wine by-products are generated, corresponding to 30% of the total quantity of vinified grapes. Wine by-products are a source of healthy bioactive molecules, such as polyphenols and other molecules (pigments, fibers, minerals, etc.). The abundance of bioactive compounds assures a promising future for nutritional foodstuff production. Wine by-products can be used to fortify aromatized waters and infusions, bread, pasta, dairy products, alcohol, sugary beverages, and processed foods. These innovative products are part of the Mediterranean diet and are of great interest to both human and environmental health. Pre-clinical studies show that consumption of food produced with wine by-products or with their extracts attenuates the inflammatory state and increases antioxidant status. As such, wine by-products provide protective effects against the underlying pathophysiological hallmarks of some chronic diseases such as atherosclerosis, diabetes, hypertension, obesity, and cancer. However, the poor bioavailability warrants further investigation on how to optimize the efficacy of wine by-products, and more clinical trials are also needed. The scientific evidence has validated the uses of the dietary nature of wine by-products and has helped to promote their use as a functional food to prevent chronic human diseases.

Research on the Potential Use of Grape Seed Flour in the Bakery Industry

Grape seeds are one of the most accessible by-products of the wine industry in large quantities (about 2.4 million t/year). Numerous researchers have shown that grape seeds have a high potential for use as a functional ingredient in the food industry due to their high content of protein, fiber, minerals, and polyphenols. The aim of the paper is to evaluate the possibilities of using grape seed flour (GSF) in the bakery industry from both chemical and rheological points of view. Research shows that grape seed flour contains about 42 times more fiber than wheat flour and approximately 9 times more calcium, 8 times more magnesium, and 2 times more potassium. To assess this potential, four samples of bread from flour mixtures with 3%, 5%, 7%, and 9% (w/w) degree of replacement with GSF were prepared, analyzed, and compared with a control sample from 100% wheat flour. From a rheological point of view, the baking qualities deteriorate: the water absorption capacity (CH) decreases from 58.2% to 55.8%, the dough stability increases from 8.50 min to 9.83 min, the α slope varies from −0.066 Nm/min to −0.104 Nm/min, the β slope increases from 0.576 Nm/min to 0.630 Nm/min, and the γ slope varies from −0.100 Nm/min to −0.198 Nm/min. The sensory analyses performed by the panel of evaluators enclosed the sensorial characteristics of the samples with 3% and 5% GSF between the two control samples made from flour types 480 and 1250. The conclusions show that the sample containing 7% and 9% are unsatisfactory from rheological and sensorial points of view and the samples with 3% and 5% can be considered a fiber source and a Cu source, respectively, and are rich in Zn.

Formulating and studying compound chocolate with adding dried grape pomace as a bulking agent

The use of dried grape pomace (DGP) as a bulking agent for partly substitution of sugar, milk powder and whey powder in compound chocolate (CC) was investigated. D-optimal mixture design was used to determine the effect of composition on the particle size, flow behaviour (Casson yield value and plastic viscosity), as well as total phenolic and resveratrol contents before and after in vitro digestion. The various models (linear, quadratic and cubic) which were identified as significant (P < 0.05) were used in this study. As a result, DGP was found suitable to be used in CC as a bulking agent to partially substitute sucrose, milk powder and whey powder to increase functional properties and decrease the cost of the CC. For CC with the most acceptable rheological properties and a satisfactory level of TPC and resveratrol, optimum usage levels of DGP were identified as 7.1% to 10.0%. Further studies will require to modify flow behaviours by optimizing the particle size of pomace.

Investigation of the possibility of fermentation of red grape juice and rice flour by Lactobacillus plantarum and Lactobacillus casei

The aim of the current study was to evaluate the possibility of the bacterial growth and substrate metabolism during the fermentation of red grape juice and the mixture of red grape juice and rice flour solution using Lactobacillus plantarum and Lactobacillus casei. In recent years, cereal-based beverages have been used as functional compounds such as antioxidants, dietary fiber, minerals, probiotics, and vitamins in diets. In this research, fermentation of red grape juice (media 1) and 1:1 mixture of red grape juice and rice flour solution (media 2) by two strains of gram positive and homofermentative lactic acid bacteria: L. plantarum and L. casei (individually and mixed) was examined. Fermentation was carried out at 37°C for 48 hr. Microbial population, pH, acidity, sugar, and organic acid metabolism were measured during the fermentation period. Data showed that in media 2 fermented with mixed culture of both L. plantarum and L. casei, acidity and microbial population increased sharply at the initial stages of fermentation, and the most percentage of lactic acid production occurred. Red grape juice fermented with mixture of L. plantarum and L. casei showed the most sugar consumption (p < .05). Results indicated that the use of the mixture of red grape juice and rice flour solution can be a proper substrate for producing lactic acid.

Chemical Composition and Functional Properties of Dietary Fibre Concentrates from Winemaking By-Products: Skins, Stems and Lees

The objective of this study was to evaluate, from a technological and nutritional point of view, the chemical composition and functional properties of the industrial winemaking by-products, namely skins, stems and lees. The chemical and physical characteristics, as well as the functional properties (fat and water retention and swelling capacity, antioxidant capacity, and their prebiotic effect), of the dietary fibre of these by-products were studied. The results showed that the skins, stems, and lees are rich in fibre, with the stem fibre containing the highest amounts of non-extractable polyphenols attached to polysaccharides with high antioxidant activity and prebiotic effect. Lee fibre had the highest water retention capacity and oil retention capacity. The results reveal that winemaking by-products could be used as a source of dietary fibre with functional characteristics for food applications.

Effect of grape seed power on the structural and physicochemical properties of wheat gluten in noodle preparation system

Noodles were prepared using wheat flour supplemented with 1%, 3%, and 5% grape seed power (GSP). The farinograph properties of wheat flour, the textural properties of the dough, and thermal properties of the gluten were determined. The microstructure was analyzed by scanning electron and atomic force microscopy, and the effects of the addition of GSP on the physicochemical and structural properties (free sulfhydryl content, surface hydrophobic region, and secondary structure) of wheat gluten protein were analyzed. 1% GSP promoted the aggregation of gluten proteins by promoting hydrophobic interactions and hydrogen bonding, thus enhanced the noodle quality. Whereas, 3% and 5% GSP addition disrupted the disulfide bonds between gluten protein molecules and formed macromolecular aggregates linked to gluten proteins through non-covalent bonds and hydrophobic interactions, which prevented the formation of the gluten protein reticulation structure. Our study emphasized the interaction between wheat proteins and GSP in noodle making dough.

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.

Optimization of Ingredients for Biscuits Enriched with Rapeseed Press Cake—Changes in Their Antioxidant and Sensory Properties

The optimum formulation for wheat flour (WF)-based biscuits containing the rapeseed press cake (RPC)—the primary by-product of rapeseed oil production rich in phenolic compounds and different types of fats (rapeseed oil, margarine and coconut oil)—was estimated using the central composite design (CCD) with two factors and response surface methodology (RSM). Effects of partial substitution of WF for RPC (0–40 g) in a total flour blend (100 g) and fats with various amounts of saturated fatty acids (SAFA = 2.3–24.9 g) on antioxidant capacity (AC) and sensory characteristics (color, odor, texture, flavor, overall acceptability, and purchase intent scores) of the novel biscuits were investigated. Conventional solid (liquid)–liquid extraction and ultrasound-assisted extraction (UAE) were applied to extract total antioxidants from main ingredients used for the preparation of doughs as well as the baked biscuits. The AC of biscuits and their components were determined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The DPPH results were the highest for the RPC flour (DPPH = 15,358–15,630 μmol Trolox (TE)/100 g) and biscuits containing rapeseed oil and 40 g of RPC flour (DPPH = 7395–10,088 μmol TE/100 g). However, these biscuits had lower sensory scores for each attribute and the lowest purchase intent scores. The quadratic response surfaces were drawn from the mathematical models in order to ensure the good quality of the proposed biscuits with RPC. The DPPH results obtained and the mean sensory scores correlate with the predicted values (R2 = 0.7751–0.9969). The addition of RPC with high antioxidant potential to biscuits and the replacement of margarine or coconut oil by rapeseed oil interfered with their acceptability.

Study of the Cluster Thinning Grape as a Source of Phenolic Compounds and Evaluation of Its Antioxidant Potential

Thinning is a common viticulture practice in warm climates, and it is applied to increase the quality of the harvest. Thinning clusters are usually discarded, and they are considered another oenological industry waste. To valorize this by-product, the phenolic content and antioxidant activity of three red varieties (Tempranillo, Cabernet Sauvignon, and Syrah), thinned at three different times between veraison and harvest, were studied: the first at the beginning of the veraison stage, in a low ripening stage; the second in an intermediate ripening stage; and, finally, the third sampling in the highest ripening stage. These by-products showed high values of total phenolic contents (10.66–11.75 mg gallic acid equivalent/g), which is of the same order as or even higher than that found in grape pomace. In thinned grape were identified 24 phenolic compounds, being the flavan-3-ols (catechin and epicatechin) of particular interest, with mean contents ranging from 105.1 to 516.4 mg/kg of thinned grape. Antioxidant activity similar to that of the vintage grape was found. It is concluded that thinned grape is a good source of phenolic compounds. Its content does not depend mainly on the grape variety; however, it has been possible to establish differences based on the maturity stage of the thinning grapes: the intermediate ripeness stage, with a Brix degree in the range of 15–16 for this area, would be the optimum collection time for cluster thinning. In this intermediate ripeness stage, thinning grapes present a higher antioxidant activity and there is also appreciable anthocyanin content, which is not found for the lowest ripeness stage, since these samples present an intermediate composition in all the families of determined phenolic compounds: anthocyanins, flavonols, flavan-3-ols, cinnamic acids, and benzoic acids. It is important to note that the experiments in this study have been carried out with whole tinned grapes, without separating the skin or the seeds.

Effects of orange peel powder on rheological properties of wheat dough and bread aging

Orange peels, the major byproduct of orange fruit processing, are a good material for functional food production because of their excellent physiological and health function. The effects of orange peel powder (OPP) on the rheological and reho-fermentation properties of high-gluten wheat dough and bread staling were investigated. The results showed that OPP significantly modified wheat dough characteristics and bread quality for its fiber, pectin and polyphenol content. Incorporation of OPP in wheat dough mainly caused competitive water absorption. It improved dough water absorption from 59.70% to 66.82% by increasing the development time (from 1.40 min to 4.51 min) and decreasing the retrogradation degree (from 1.01% to 0.68%) at a low content (no more than 5%) but showed adverse effects at higher content because of stronger gluten-dilution action than excessive water sequestration of OPP. It strengthened the dough elasticity by increasing the value of storage modulus (G') and loss modulus (G″) of dough samples at all contents, G' and G″ value of dough sample containing 7% OPP was more than twice that of the wheat dough. Alveograph and rheofermentographic parameters confirmed that OPP improved the total volume of CO2 production from 1774.11 ml (wheat dough) to 2,458.30 ml (dough sample containing 7% OPP) but reduced the gas retention coefficient from 71.86% to 66.52% during fermentation accordingly. Additionally, no remarkable deterioration of the bread staling was observed. These results contributed to the interpretation of the action mechanism of OPP modification on the wheat dough structure and further guided the application of OPP on cereal product development.

The dose-response effect on polyphenol bioavailability after intake of white and red wine pomace products by Wistar rats

Wine pomace by-products are an important source of phenolic acids with significant health benefits. However, phenolic acid bioavailability in vivo has been little studied and there are few comparative studies on bioavailability between red and white wine pomace and the effect of intake of different doses. The qualitative and quantitative profile of phenolic acid metabolites in plasma and urine samples from Wistar rats was obtained by gas chromatography/mass detection, after oral administration of four doses (50, 100, 150, and 300 mg) of both the red and the white wine pomace products (rWPP and wWPP, respectively). The antioxidant capacity of the plasma samples assessed by both the ABTS and the FRAP levels was also evaluated. The results showed that neither the bioavailability nor the antioxidant capacity in vivo of the rWPP increased at high doses. However, both parameters were dependent on the intake of the wWPP.

Grape Pomace Valorization: A Systematic Review and Meta-Analysis

This systematic review aimed to collect data and analyze the possible use of grape pomace, a winemaking industry byproduct, in the production of fortified foods. The English articles found in Web of Science, Scopus, and Google Scholar, from January 2006 until May 2020, were used for the conduction of overview tables and meta-analysis. The systematic review emphasized the two main issues concerning grape pomace application to other food products: (i) grape pomace contains high amounts of health promoting compounds; and (ii) the use of grape pomace is influencing the waste management. The grape pomace has been used in the fortification of plant origin food, meat, fish, and dairy products, mainly due to higher polyphenols and dietary fiber contents. The fortification was declared as successful in all studied food types. The change of color, caused by polyphenolic compounds, was mainly observed as an adverse effect of the fortification. Higher levels of fortification also caused notable undesirable changes in texture. The most valuable influence of the grape pomace addition according to included papers and meta-analysis is certainly a higher nutritional quality and oxidative stability of fortified products, reflected as higher polyphenol and total dietary fiber content.

Pre-Hydrated Berry Pomace in Wheat Bread: An Approach Considering Requisite Water in Fiber Enrichment

Using blackcurrant pomace, for instance, in bread, prevents wasting this by-product of fruit juice production, thereby also taking advantage of its nutritional benefits. This study investigated the effects of blackcurrant pomace incorporation in wheat dough and the quality of the resulting breads. Two concepts were addressed: (a) adjusting the water level based on the dough consistency and (b) preparing pre-hydrated pomace by applying the determined water content prior to dough preparation and using it for bread making. Samples with wholegrain spelt flour were used for additional comparison. This study revealed that instant pomace incorporation with an adjusted water level diminished the dough stickiness and baking loss, but resulted in stiffer dough with delayed proofing and a decreased bread volume. The kneading resistance pointed to continued swelling after kneading, concomitant with a lower amount of available free water. Counteracting the competition for water of the flour components and pomace fiber by applying pre-hydrated pomace turned out to be successful. The deteriorating effects were reduced to a larger extent by pomace hydrated in hot water. Despite a similar composition, the products of wholegrain spelt flour deviated from the pomace formulations as well as from wheat breads (producing the highest water absorption but smallest loaves). As the water absorption of pomace fiber largely influences the product properties, a pre-hydration of pomace to be included in wheat dough can be highly recommended to enhance processing properties and product quality.

Non-Extractable Polyphenols from Food By-Products: Current Knowledge on Recovery, Characterisation, and Potential Applications

Non-extractable polyphenols (NEPs), or bound polyphenols, are a significant fraction of polyphenols that are retained in the extraction residues after conventional aqueous organic solvent extraction. They include both high molecular weight polymeric polyphenols and low molecular weight phenolics attached to macromolecules. Current knowledge proved that these bioactive compounds possess high antioxidant, antidiabetic, and other biological activities. Plant-based food by-products, such as peels, pomace, and seeds, possess high amount of NEPs. The recovery of these valuable compounds is considered an effective way to recycle food by-products and mitigate pollution, bad manufacturing practice, and economic loss caused by the residues management. The current challenge to valorise NEPs from plant-based by-products is to increase the extraction efficiency with proper techniques, choose appropriate characterising methods, and explore potential functions to use in some products. Based on this scenario, the present review aims to summarise the extraction procedure and technologies applied to recover NEPs from plant-based by-products. Furthermore, it also describes the main techniques used for the characterisation of NEPs and outlines their potential food, pharmaceutical, nutraceutical, and cosmetic applications.

Potential of grape byproducts as functional ingredients in baked goods and pasta

Wine making industry generates high quantities of valuable byproducts that can be used to enhance foods in order to diminish the environmental impact and to obtain more economic benefits. Grape byproducts are rich in phenolic compounds and dietary fiber, which make them suitable to improve the nutritional value of bakery, pastry, and pasta products. The viscoelastic behavior of dough and the textural and the sensory characteristics of baked goods and pasta containing grape byproducts depend on the addition level and particle size. Thus, an optimal dose of a finer grape byproducts flour must be found in order to minimize the negative effects such as low loaf volume and undesirable sensory and textural characteristics they may have on the final product quality. In the same time, an enrichment of the nutritional and functional value of the product by increasing the fiber and antioxidant compounds contents is desired. The aim of this review was to summarize the effects of the chemical components of grape byproducts on the nutritional, functional, rheological, textural, physical, and sensory characteristics of the baked goods and pasta. Further researches about the impact of foods enriched with grape byproducts on the human health, about molecular interactions between components, and about the effects of grape pomace compounds on the shelf life of baked goods and pasta are recommended.

The influence of the extrusion process on the nutritional composition, physical properties and storage stability of black chokeberry pomaces

The study examined the influence of the process of extrusion on the physical properties and nutritional composition of black chokeberry pomaces. It has been determined that the extrusion process resulted in a reduction of the content of anthocyanins and fibre, but an increase of the contribution of simple sugars. In order to assess the phase transitions occurring in the products, a state diagram was utilized, which was constructed using the freezing and vitrification curve and values characterizing the conditions of maximum cryoconcentration. The determined values of critical water activity (based on water activity concepts) indicate that pomaces and extrudates retain crispiness in storage under moderate environmental relative humidity conditions. However, in the case of the glass transition concept, the determined values of water activity indicate that products stored in room temperature must be protected against the influence of humidity.

Sensory acceptability of value added cookies incorporated with Tinospora cordifolia (TC) stem powder; improvement in nutritional properties and antioxidant potential

Tinospora cordifolia (TC) is regarded nature's treasure as it is salutary in various ways to the human health in ayurvedic and vedic scriptures. The TC stem creeping on neem tree (Azadirachta indica) are considered best for medicinal use. Present study was carried out to develop functional food as cookies by incorporating the TC stem powder. Functional cookies were prepared by incorporating 2%, 4%, 8%, 10% and 12% of TC stem powder and admissibility was decided on the basis of sensory evaluation to get the optimized cookies (TCC). Further physical parameters (L*, a* and b* color value and spread ratio) were analyzed. TC, TCC and control cookies without TC were evaluated for nutritional composition and antioxidant potential [antioxidant assays: 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing power (FRAP) and nitric oxide (NO), total polyphenolic content and total flavonoid content]. Results showed that with increase in TC addition from 0 to 12% in cookies there was decreases in the sensory parameters and maximum admissible concentration was up to 8% of TC, hence optimized at this level. Incorporation of TC in cookies resulted in increase in b^* value, protein, moisture, total ash, iron, copper, zinc and antioxidant potential, whereas the fat content decreases. Developed cookies proved to be better than standard control cookies with respect to functional properties.