Recovery potential of cold press byproducts obtained from the edible oil industry: physicochemical, bioactive, and antimicrobial properties

Harnessing Nature's Toolbox: Naturally Derived Bioactive Compounds in Nanotechnology Enhanced Formulations

The vast diversity of plants in nature offers a rich reservoir of bioactive compounds that have historically played an integral role in pharmacotherapy and continue to serve as a primary source of novel therapeutic agents. Medicinal plants contain a multitude of secondary metabolites with pharmacological potential, making them indispensable in drug discovery and development. These bioactive constituents, inherent in herbal remedies, exhibit a wide range of medicinal properties due to their complex chemical compositions and structural diversity. Despite their therapeutic potential, the clinical application of crude plant extracts is often hindered by limitations, such as poor bioavailability, low biostability, and variable efficacy. These issues can diminish the therapeutic impact of plant-derived compounds. Nanotechnology presents an innovative approach to addressing these challenges through the development of nanoformulations that enhance the efficacy of bioactive compounds. This review examines both historical and recent studies on the synthesis and characterization of bioactive compounds, focusing on their effectiveness in treating various diseases. Additionally, it addresses the risks associated with the direct use of crude plant extracts in medicine, explores extraction and isolation techniques, and reviews research from the past five years on the development of bioactive compounds, their nanoformulations, and their applications in disease treatment. The review also presents recent clinical trials conducted over the last five years on crude extracts and their nanoformulated counterparts, providing insights into the clinical translation of these natural therapeutics.

Exploring the characteristics, digestion behaviors, and nutraceutical potential of the underutilized Chimonanthus praecox (L.) link kernel oil: A combined in vitro and in vivo study

Chimonanthus praecox (L.) Link kernel oil (LMO) has the potential to expand the variety of nutraceutical plant oils available and provide support for the application of functional food. This study aimed to assess the edible potential of LMO by examining its physicochemical characteristics, digestion behaviors, and nutraceutical properties. The results revealed that LMO has a high oil content of 40.84% and is particularly rich in linoleic acid (53.37-56.30%), oleic acid (22.04-25.08%) and triacylglycerol (TAG) of linoleic acid -palmitoleic acid- oleic acid (10.57-12.70%). The quality characteristics and phytochemical composition of LMO were found to be influenced by variety and extraction methods used. In simulated in vitro digestion tests, LMO showed a better lipid release rate and degree. Animal studies further demonstrated that LMO led to better TAG and cholesterol excretion compared to soybean oil and camellia oleifera oil. Overall, this study highlights the potential of LMO as a high-quality edible oil.

Microbiological Safety and Functional Properties of a Fermented Nut-Based Product

Fermented nut-based products, obtained after soaking and fermentation, are gaining increasing interest as animal food substitutes because of ethical, environmental and health reasons. In these products, Lactic Acid Bacteria (LAB) perform the fermentation, leading to matrix acidification and contributing to controlling spoilage and pathogenic microbiota. In this work, LAB strains isolated from an artisanal product and combined with a commercial strain were added as starter cultures during nut soaking to produce a cheese-like fermented plant-based product. Three different LAB consortia were used in challenge tests at laboratory scale against Listeria monocytogenes, Escherichia coli or Salmonella Enteritidis, inoculated in nuts at 5 log CFU/g, and monitored for pathogen survival and matrix acidification. The combination of Lactiplantibacillus plantarum 82 and Leuc. carnosum 4010 resulted in faster acidification (pH value < 4.4 after 18 h instead of 48 h) and the reduction of target pathogens; L. monocytogenes was already absent after seven days from production, and the counts of E. coli or S. Enteritidis were lower with respect to other samples. Thus, this microbial consortium was used for a pilot-scale production in which, beyond safety, the fermented plant-based product was also characterized for aroma profile and phenolic compounds, parameters that are known to be affected by LAB fermentation. The results showed an enhancement of the aroma profile, with an accumulation of molecules able to confer cheese-like notes (i.e., acetoin and diacetyl) and higher phenolic content, as well as the presence of compounds (i.e., phenyllactic acid and hydroxyphenyllactic acid) that could exert antimicrobial activity. This study allowed us to set up a guided fermentation for a cheese-like vegan product, guaranteeing safety and improving aromatic and functional features.

Comparative Analysis of Grape Seed Oil, Linseed Oil, and a Blend: In Vivo Effects of Supplementation

Grape seeds are rich in bioactive substances, including polyphenols, terpenoids, and phytosterols. Linseed (Linum usitatissimum L.) boasts a high concentration of polyunsaturated fatty acids (PUFAs), lignans, phytoestrogens, and soluble fibers, all contributing to its therapeutic potential. In this study, we pioneered the formulation of an oil blend (GL) combining grape seed oil (G) and golden linseed oil (GL) in equal volumes (1:1 (v/v)) and we evaluated in terms of the nutritional, physical, and chemical properties and their influence in an in vivo experimental model. We analyzed the oils by performing physical-chemical analyses, examining the oxidative stability using Rancimat; conducting thermal analyses via thermogravimetry/derivative thermogravimetry (TG/DTG) and differential scanning calorimetry (DSC), performing optical UV-vis absorption analyses; examining the fluorescence emission-excitation matrix, total carotenoids, and color, and conducting metabolic assessments in an in vivo experimental trial. The fatty acid profile presented a higher fraction of linoleic acid (C18:2) in G and GL and alpha-linolenic acid (C18:3) in L. The acidity and peroxide indices were within the recommended ranges. The TG/DTG, DSC, and Rancimat analyses revealed similar behaviors, and the optical analyses revealed color variations caused by carotenoid contents in L and GL. In the in vivo trial, G (G2: 2000 mg/kg/day) promoted lower total consumption, and the blend (GL: 2000 mg/kg/day) group exhibited less weight gain per gram of consumed food. The group with G supplementation (G2: 2000 mg/kg/day) and GL had the highest levels of HDL-c. The group with L supplementation (L2: 2000 mg/kg/day) had the lowest total cholesterol level. The L2, G1 (1000 mg/kg/day), and G2 groups exhibited the lowest MCP-1 and TNF-α values. Additionally, the lowest adipocyte areas occurred in G and GL. Our results suggest that this combination is of high quality for consumption and can influence lipid profiles, markers of inflammation, and antioxidant status.

Cold-Pressed Okra Seed Oil Byproduct as an Ingredient for Muffins to Decrease Glycemic Index, Maillard Reaction, and Oxidation

This study aimed to investigate the effects of adding cold-pressed okra seed oil byproduct (OSB) to the muffin formulation, as a partial substitute for wheat flour, on the nutritional, physicochemical, rheological, textural, and sensory properties of muffins. The carbohydrate, protein, oil, moisture, and ash contents of OSB were 44.96, 32.34, 10.21, 7.51, and, 4.98%, respectively, indicating that OSB was rich in protein and carbohydrate. All muffin samples showed a shear thinning behavior, indicating that the viscosity of all samples decreased with increasing shear rate. The frequency sweep test showed that all samples showed viscoelastic solid-like structure [G' (storage modulus)> G″ (loss modulus)]. The K' values (between 66.45 and 139.14) were higher than the K″ values (between 36.62 and 80.42) for all samples. The result was another indication of the viscoelastic solid characteristic of the samples. In our study, it was found that the fluorescence of advanced Maillard products and soluble tryptophan index decreased with increasing amount of OSB, indicating that OSB addition led to a decrease in the amount of fluorescent Maillard reaction (MR) products. The fortified muffins with more than 10% OSB had a reduced estimated glycemic index (GI) significantly in comparison with control muffin samples (p < 0.05). The induction period (IP) values of the muffin samples containing OSB (between 11:57 and 15:15 h/min) were higher than the IP value of the control sample (10:50 h/min), indicating that OSB improved the oxidative stability of the muffin samples. The addition of OSB has shown no negative effect on sensory attributes considering texture, mouth fell, odor, and taste. This study suggested that the addition of OSB in muffins could improve rheological properties and oxidative stability and decrease GI and the amount of MR products without negative impact on sensory properties.

Caffeine-Containing Emulsion: Influence of the HLB and Mixing Proportions, the Oil's Chemical Composition, and the Existence of Caffeine on Emulsion Properties

This study employs a low-energy emulsification method to prepare caffeine-containing emulsions, denoted as Caf-EM. Three different oils, including coconut, sesame, and grape seed oils, are utilized along with the surfactants Span 80 and Tween 80. We investigate the influence of various factors, including (i) the hydrophilic-lipophilic balance (HLB) and surfactant ratio, (ii) the chemical composition of the oils, and (iii) the presence of caffeine, on the stability and size of emulsions. The results indicate that the HLB value and surfactant ratio are the most crucial factors affecting the emulsions' stability. The most stable Caf-EM formulation is achieved by combining mixed surfactants of Span 80 and Tween 80 with an optimal HLB value of 6.4 at a concentration of 15% (S15 to 6.4) across all oil types. This specific ratio also leads to significantly smaller emulsion droplet sizes than other ratios and is the only ratio that produces stable emulsions even without caffeine (denoted as EM). Notably, formulation S15-6.4 additionally causes a phase inversion from oil-in-water (O/W) to water-in-oil (W/O). Furthermore, the presence of caffeine in the water phase contributes to the formation of smaller and more stable emulsions. The particle size of Caf-EM is approximately 1.5 times smaller than that of EM. Regarding the oil's chemical composition, while there is a discernible trend in emulsion droplet size (coconut oil > grape seed oil > sesame oil), the differences within this sequence are insignificant, suggesting that the oil's chemical composition does not have a pronounced effect.

Phytochemical Statistical Mapping of Red Grape Varieties Cultivated in Romanian Organic and Conventional Vineyards

Red grapes are rich in phytochemicals such as phenolics and flavonoids, which are strongly correlated with their antioxidant activity. Thus, grapes as-harvested and grape extracts, especially those obtained from their seeds and pulp, have been reported to have health benefits, and accordingly, grapes and their derivatives are considered potential functional food ingredients. The total phenolic content, total flavonoid content, and the antioxidant activity of skin, pulp, and seeds of four grape varieties grown both in conventional and organic vineyards were examined in this study. Phytochemical characteristics of one native Romanian variety, Feteasca Neagra, were compared with data measured for three red grape varieties more commonly cultivated worldwide (Merlot, Pinot Noir, and Muscat Hamburg). It was found that the seeds of the Pinot Noir variety grown in an organic system contained the highest total phenolics of 169.53 ± 7.32 mg gallic acid equivalents/g and the highest total flavonoid content of 388.25 ± 10.72 mg quercetin equivalents/g, values corresponding to high antioxidant activity (312.84 ± 12.81 mg ascorbic acid equivalents/g). The total flavonoid content in the hydroalcoholic extracts obtained from seeds of Pinot Noir (organic vineyard) was around 24.5-fold higher than that of the skin of Pinot Noir (conventional vineyard). Experiments showed that seeds of all four tested grape varieties are good sources of total flavonoids, not only of total phenolics. When referring to the organic vineyard, the skin and pulp grapes showed good results for the total phenolic content. The antioxidant activities of the hydroalcoholic extracts were well-correlated with the total phenolic content and total flavonoid content. Lower values of these parameters were found for extracts obtained from skin and pulp than for those obtained from seeds of the same grape variety regardless of the culture management system (organic/conventional). Data mining techniques such as regression analysis, principal component analysis, and clustering analysis were applied to establish the potential correlation between the phytochemical content and the antioxidant activities of the red grapes on the one hand, and grape variety, anatomical parts, and vineyard type (organic/conventional) on the other hand.

Nutraceutical Potential of Grape (Vitis vinifera L.) Seed Oil in Oxidative Stress, Inflammation, Obesity and Metabolic Alterations

Vitis vinifera L. (grapevine) is a perennial plant of the Vitaceae family that is widely used to produce grapes and wines. Grape seed oil is rich in fatty acids such as linoleic acid (65-75%), vitamin E (50 mg), and phytosterols in addition to phenolic compounds, such as catechins (414 mg), epicatechins (130.4 mg), and gallic acid (77 µg), shows promise as a nutritional compound and is outstanding as a therapeutic substance with active properties for health, detected mainly by in vitro studies, as well as some in vivo studies. The benefits of consuming this oil include modulating the expression of antioxidant enzymes, anti-atherosclerotic and anti-inflammatory effects, and protection against oxidative cell damage and some types of cancer. However, experimental findings confirm that therapeutic functions remain scarce; thus, more studies are needed to determine the mechanisms of action involved in the indicated therapeutic qualities.

Tiger nut (Cyperus esculentus L.) oil: A review of bioactive compounds, extraction technologies, potential hazards and applications

Tiger nut is a tuber of a plant native in the Mediterranean coastal countries, which is of great interest in food industry due to its richness in carbohydrates, lipids, starches, minerals, etc. Recent studies have focused on the analysis of the phytochemical composition of tiger nut, including six essential nutrients, polyphenols, and the extraction of proteins, starches, and phenolic compounds from the by-products of tiger nut milk 'horchata'. Few works were focused on the possibility of using tiger nut oil, a nutritious oil comparable to olive oil, as an edible oil. Therefore, this review discussed some extraction technologies of tiger nut oil, and their effects on the properties of oil, such as bioactive compounds, oxidative stability and potential hazards. The information on the emerging applications of tiger nut oil was summarized and an outlook on the utilization of tiger nut oil by-products were also reviewed.

Capsaicin Rich Low-Fat Salad Dressing: Improvement of Rheological and Sensory Properties and Emulsion and Oxidative Stability

This study aimed to investigate the potential use of cold-pressed hot pepper seed oil by-product (HPOB) in a low-fat salad dressing to improve its rheological properties, emulsion, and oxidative stability. The total phenolic content (TPC), the 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity, and CUPRIC reducing antioxidant capacity (CUPRAC) values were 317.4 mg GAE/100 g, 81.87%, and 6952.8 mg Trolox/100 g, respectively. The capsaicin, dihydrocapsaicin, and total carotenoid content were 175.8 mg/100 g, 71.01 mg/100 g, and 106.3 µg/g, respectively. All emulsions indicated shear-thinning, viscoelastic solid-like behavior, and recoverable characteristics, which were improved via enrichment with HPOB. The thermal loop test showed that the low-fat sample formulated with 3% HPOB indicated little change in the G* value, showing that it exhibited high emulsion stability. The induction period values (IP) of the salad dressing samples containing HPOB (between 6.33 h and 8.33 h) were higher than the IP values of the control samples (3.20 h and 2.58 h). The enrichment with HPOB retarded the formation of oxidative volatile compounds of hexanal, nonanal, and 1-octene-3-ol. According to the results presented in this study, HPOB could be effectively used in a low-fat salad dressing to enhance its rheological characteristics and oxidative stability.

Valorization of wastes and by-products of nuts, seeds, cereals and legumes processing

Wastes and by-products of nuts, seeds, cereals and legumes carry a unique potential for valorization into value-added ingredients due to their protein, dietary fiber, antioxidant, vitamin and mineral contents. The most crucial factor in the recovery of value-added ingredients and bioactives from the wastes and by-products is the utilization of the most efficient extraction technique. This work is an overview of the classification of wastes and by-products of nuts, seeds, cereals and legumes processing, the methods used in the extraction of valuable compounds such as proteins, dietary fibers, phenolics, flavonoids and other bioactives. This chapter provides insights on the promising applications of extracted ingredients in various end products. A special emphasis is given to the challenges and improvement methods for extraction of value-added compounds from wastes and by-products of nuts, seeds, cereals and legumes processing.

Low-Fat Salad Dressing as a Potential Probiotic Food Carrier Enriched by Cold-Pressed Tomato Seed Oil By-Product: Rheological Properties, Emulsion Stability, and Oxidative Stability

This study aims to investigate the potential of the use of cold-pressed tomato seed oil by-products in a low-fat salad dressing as potential probiotic food carriers to improve the oxidative stability and emulsion stability as well as the rheological properties. The low-fat salad dressing emulsions were formulated with cold-pressed tomato seed by-product (TBP) and Lactobacillus plantarum ELB90. The optimum low-fat salad dressing formulations found were determined as 10 g/100 g oil, 0.283 g/100 g xanthan, and 2.925 g/100 g TBP. The samples prepared with the optimum formulation (SD-O) were compared with the low-fat control salad dressing sample (SD-LF) and the high-fat control salad dressing sample (SD-HF) based on the rheological properties, emulsion stability, oxidative stability, and L. plantarum ELB90 viability. The sample SD-O showed shear-thinning, viscoelastic solid, and recoverable characters. The sample SD-O showed higher IP and ΔG ⁺⁺ and lower ΔS ⁺⁺ values than those of the control samples. After 9 weeks of refrigerated storage, viable L. plantarum ELB90 cell counts of salad dressing samples were counted as 7.93 ± 0.03, 5.81 ± 0.04, and 6.02 ± 0.08 log cfu g^-1 for SD-O, SD-LF, and SD-HF, respectively. This study showed that TBP could be successfully used in a low-fat salad dressing as a potential probiotic carrier.

Multi-Step Biomass Fractionation of Grape Seeds from Pomace, a Zero-Waste Approach

Grape seeds are the wineries' main by-products, and their disposal causes ecological and environmental problems. In this study seeds from the pomace waste of autochthonous grape varieties from Lebanon, Obeidi (white variety) and Asswad Karech (red variety) were used for a multi-step biomass fractionation. For the first step, a lipid extraction was performed, and the obtained yield was 12.33% (w/w) for Obeidi and 13.04% (w/w) for Asswad Karech. For the second step, polyphenols' recovery from the defatted seeds was carried out, resulting in 12.0% (w/w) for Obeidi and 6.6% (w/w) for Asswad Karech, with Obeidi's extract having the highest total phenolic content (333.1 ± 1.6 mg GAE/g dry matter) and antioxidant activity (662.17 ± 0.01 µg/mL of Trolox equivalent). In the third step, the defatted and dephenolized seeds were subsequently extracted under alkaline conditions and the proteins were isoelectric precipitated. The recovered protein extract was 3.90% (w/w) for Obeidi and 4.11% (w/w) for Asswad Karech seeds, with Asswad Karech's extract having the highest protein content (64 ± 0.2 mg protein/g dry matter). The remaining exhausted residue can be valorized in cosmetic scrubs formulations as a replacement for plastic microbeads. The designed zero-waste approach multi-step biomass fractionation has the potential to improve the valorization of the side products (grape seeds) of these two Lebanese autochthonous grape varieties.

An Updated Review on Prebiotics: Insights on Potentials of Food Seeds Waste as Source of Potential Prebiotics

Prebiotics are a group of biological nutrients that are capable of being degraded by microflora in the gastrointestinal tract (GIT), primarily Lactobacilli and Bifidobacteria. When prebiotics are ingested, either as a food additive or as a supplement, the colonic microflora degrade them, producing short-chain fatty acids (SCFA), which are simultaneously released in the colon and absorbed into the blood circulatory system. The two major groups of prebiotics that have been extensively studied in relation to human health are fructo-oligosaccharides (FOS) and galactooligosaccharides (GOS). The candidature of a compound to be regarded as a prebiotic is a function of how much of dietary fiber it contains. The seeds of fruits such as date palms have been reported to contain dietary fiber. An increasing awareness of the consumption of fruits and seeds as part of the daily diet, as well as poor storage systems for seeds, have generated an enormous amount of seed waste, which is traditionally discarded in landfills or incinerated. This cultural practice is hazardous to the environment because seed waste is rich in organic compounds that can produce hazardous gases. Therefore, this review discusses the potential use of seed wastes in prebiotic production, consequently reducing the environmental hazards posed by these wastes.

Use of Grape By-Products to Enhance Meat Quality and Nutritional Value in Monogastrics

Grape by-products could be used in monogastric animals' nutrition to reduce feeding costs with conventional crops (e.g., maize and soybean meal) and to improve meat quality. The main grape by-products with the largest expression worldwide, particularly in the Mediterranean region, are grape pomace, grape seed, grape seed oil and grape skins. These by-products are rich sources of bioactive polyphenols, dietary fiber and polyunsaturated fatty acids (PUFA), more specifically, the beneficial n-3 PUFA, that could be transferred to pork and poultry meat. The potential biological activities, mainly associated with antimicrobial and antioxidant properties, make them putative candidates as feed supplements and/or ingredients capable of enhancing meat quality traits, such as color, lipid oxidation and shelf life. However, grape by-products face several limitations, namely, the high level of lignified cell wall and tannin content, both antinutritional compounds that limit nutrients absorption. Therefore, it is imperative to improve grape by-products' bioavailability, taking advantage of enzyme supplementation or pretreatment processes, to use them as feed alternatives contributing to boost a circular agricultural economy. The present review summarizes the current applications and challenges of using grape by-products from the agro-industrial sector in pig and poultry diets aiming at improving meat quality and nutritional value.

Grape By-Products as Feedstuff for Pig and Poultry Production

Grape by-products are exceptional options for replacement of conventional and unsustainable feed sources, since large amounts are generated every year from the winery industry. However, the majority is wasted with severe environmental and economic consequences. The present review aimed to evaluate the effects of grape by-products on pig and poultry growth performance. The most recent literature was reviewed using ScienceDirect and PubMed databases and the results of a total of 16 and 38 papers for pigs and poultry, respectively, were assessed. Fewer studies are documented for pig, but the incorporation of grape by-products up to 9% feed led to an improvement in growth performance with an increase in average daily gain. Conversely, lower levels (<3% feed) are needed to achieve these results in poultry. The beneficial effects of grape by-products on animal performance are mainly due to their antioxidant, antimicrobial, and gut morphology modulator properties, but their high level of cell wall lignification and content of polyphenolic compounds (e.g., tannin) limits nutrient digestion and absorption by monogastric animals. The use of exogenous enzymes or mechanical/chemical processes can provide additional nutritional value to these products by improving nutrient bioavailability. Overall, the valorization of grape by-products is imperative to use them as feed alternatives and intestinal health promoters, thereby contributing to boost circular agricultural economy.

Chitosan Film Functionalized with Grape Seed Oil—Preliminary Evaluation of Antimicrobial Activity

Although the fishing and wine industries undoubtedly contribute significantly to the economy, they also generate large waste streams with considerable repercussions on both economic and environmental levels. Scientific literature has shown products can be extracted from these streams which have properties of interest to the cosmetics, pharmaceutical and food industries. Antimicrobial activity is undoubtedly among the most interesting of these properties, and particularly useful in the production of food packaging to increase the shelf life of food products. In this study, film for food packaging was produced for the first time using chitosan extracted from the exoskeletons of red shrimp (Aristomorpha foliacea) and oil obtained from red grape seeds (Vitis vinifera). The antimicrobial activity of two films was analyzed: chitosan-only film and chitosan film with the addition of red grape seed oil at two different concentrations (0.5 mL and 1 mL). Our results showed noteworthy antimicrobial activity resulting from functionalized chitosan films; no activity was observed against pathogen and spoilage Gram-positive and Gram-negative bacteria, although the antimicrobial effects observed were species-dependent. The preliminary results of this study could contribute to developing the circular economy, helping to promote the reuse of waste to produce innovative films for food packaging.

Byproducts from the Vegetable Oil Industry: The Challenges of Safety and Sustainability

Food loss and food waste are a global challenge as about one third of all food produced around the globe is lost or wasted at some point in the food supply chain, from the farm to the fork. Vegetable oils generate a considerable amount of waste and byproducts, and such byproducts represent valuable opportunities for the food industry. Given the obvious benefits of using byproducts, special attention should be paid to the safety issues, especially when it comes to reintroducing them into the food chain. In this study, the quality and safety of several vegetable oil industry byproducts were evaluated in order to further consider them as potential ingredients in functional foods. Microbiological tests, mycotoxin assessments, and a heavy metal analysis were performed. The microbiological analysis showed reduced contamination with spoilage microorganisms, and a lack of contamination with pathogenic bacteria. All of the samples noted levels of deoxynivalenol, and, with a few exceptions, the heavy metal levels were below the maximum allowed limits. This study also notes the lack of regulation for this category of products. This not only puts the possibility of capitalizing on many food byproducts at risk, but also their widespread use as ingredients for the production of new functional products and their safe consumption.

Fatty Acids and Triacylglycerols Profiles from Sicilian (Cold Pressed vs. Soxhlet) Grape Seed Oils

Among the Sicilian economic productive sectors, that of wine production has today a considerable economic value. However, with the growth of this sector, notable was the increase in the production of waste, which to date is not only an economic damage for companies, but also a threat to the environment. It is known that waste from wine production has properties (e.g., antioxidants) which have potential reuse at cosmetic, pharmaceutical and nutritional levels to obtain economically sustainable applications. A new goal is given by the recovery of added value compounds from agri-food wastes and by-products. Grape seed oil is a promising vegetable fat and cold pressing does not involve the use of chemicals, which are harmful to health. It implies that cold-pressed seed oils may contain phytochemicals, as well as natural antioxidants, more than refined oils. In this context, this works aims at studying the chemical characterization (triglycerides profile and composition in fatty acids) of grape seed oils obtained from Soxhlet and cold pressed extraction from Sicilian red grape seeds and white grape seeds. The possibility of obtaining high yields of triglycerides and fatty acids from the waste of wine production through new extraction methods would open up new perspectives for the reuse of waste in a human and animal food context. The results of this work allow the opening up of new perspectives to reuse and then reduce these wastes, helping not only to reduce the damage to the environment and costs for companies but also to create a new product that is environmentally sustainable and with an important economic value.

The Potential Use of Cold-Pressed Pumpkin Seed Oil By-Products in a Low-Fat Salad Dressing: The Effect on Rheological, Microstructural, Recoverable Properties, and Emulsion and Oxidative Stability

The cold-pressed pumpkin seed oil by-product (POB) was evaluated for its application as a natural fat substitute and stabilizer in the reduced-fat salad dressings. For this aim, the samples were prepared by combining the xanthan gum (0.2–0.4 g/100 g), POB (1.0–5.0 g/100 g), egg yolk powder (3 g/100 g), and sunflower oil (10–30 g/100 g) in 17 different formulations. The optimization was carried out using response surface methodology (RSM) and full factorial central composite design (CCD). Results showed that all samples presented the shear-thinning (or pseudoplastic) flow behavior with 3.75–16.11 Pa·sⁿ and 0.18–0.30, K and n values, respectively. The flow behavior rheological data were fitted to a power-law model (R² > 0.99). The samples with high POB and low oil content showed similar K and n values compared to high oil content samples. Additionally, the dynamic rheological properties and three interval thixotropic test (3-ITT) were determined. The G′ value was larger than G″ in all frequency ranges, indicating viscoelastic solid characteristics in all samples. The optimum formulation was determined as 0.384% XG, 10% oil, and 3.04% POB. The samples prepared with the optimum formulation (POBLF-SD) were compared to low-fat (LF-SD), and high-fat (HF-SD) control salad dressing samples based on the rheological properties, emulsion stability, oxidative stability, zeta potential, and particle size. The oxidation kinetic parameters namely, IP, E_a, ΔS⁺⁺, and ΔG⁺⁺ showed that the oxidative stability of salad dressing samples could be improved by enriched by POB. The results of the present study demonstrated that POB could be considerably utilized as a natural fat substitute and stabilizer in salad dressing type emulsions.

The Effect of Cold Press Chia Seed Oil By-Products on the Rheological, Microstructural, Thermal, and Sensory Properties of Low-Fat Ice Cream

This study aimed to investigate the utilization of cold-pressed chia-seed oil by-products (CSOB) in a low-fat ice cream formulation as a fat replacer and stabilizer. In the study, ice cream emulsion mixtures were formulated by using 0.2–0.4% xanthan gum (XG), 2.5–12.5% fat, and 1–3% CSOB. Optimization was performed using the response surface methodology (RSM) and full factorial central composite design (CCD) based on the flow behavior rheological properties of the emulsions obtained from 17 different experimental points. All of the emulsion samples showed non-Newtonian shear-thinning flow behavior. The consistency coefficient (Κ) values of the emulsion samples were found to be 4.01–26.05 Pasⁿ and were significantly affected by optimization parameters (p < 0.05). The optimum formulation was determined as 0.29% XG, 2.5% CSOB, 2.5% fat. The low-fat (LF-IC) and full-fat control samples (FF-IC) were compared to samples produced with an optimum formulation (CBLF-IC) based on the steady shear, frequency sweep, and 3-ITT (three interval thixotropy test) rheological properties, thermal properties, emulsion stability, light microscope images, and sensory quality. CBLF-IC showed similar rheological behavior to FF-IC. The mix of CBLF-IC showed higher emulsion stability and lower poly-dispersity index (PDI) value and fat globule diameters than those of FF-IC and LF-IC. The thermal properties of the samples were significantly affected by the addition of CSOB in an ice cream mix. CBLF-IC exhibited a lower temperature range (ΔT), enthalpy of fusion (ΔH_f), and freezing point temperature (T_f) than those of FF-IC and LF-IC. While CBLF-IC exhibited a higher overrun value than other samples, it showed similar sensory properties to the FF-IC sample. The results of this study suggested that CSOB could be used successfully in low-fat ice cream production. This study also has the potential to gain new perspectives for the evaluation of CSOB as a fat substitute in a low-fat ice cream.

Effect of Plant Biostimulants on Nutritional and Chemical Profiles of Almond and Hazelnut

The increasing interest in natural foods with functional effects demands progressively higher production levels. Nonetheless, there is an orientation towards practicing more sustainable agriculture, free from environmentally harmful pesticides and fertilizers. Plant biostimulants, a class of bio-based agriculture products designed to improve crop development, represent a feasible alternative to chemical fertilizers, or, at least, an effective way of reducing the employed quantities. Herein, different types of plant biostimulants compatible with organic farming (Phytoalgae, Foliar B, Amino Acids, Soil B, Fitoalgas Green® and Sprint Plus®) were tested in two of the most important nut products worldwide: almonds and hazelnuts, which were tested for nutritional parameters, fatty acids profiles and tocopherols contents. Overall, the most notorious effects in almond samples were obtained with phytoalgae (seaweed Ascophyllum nodosum extracts), particularly reflected in the upraising around 10% of γ-tocopherol and β-tocopherol contents. Likewise, hazelnuts treated with NPK + phytoalgae were also characterized by an increase of almost 18% in tocopherols levels, while treatment with NPK alone induced 15.1% higher percentage of linoleic acid.

Crystallization and melting properties studied by DSC and FTIR spectroscopy of goldenberry (Physalis peruviana) oil

The chemical and thermal characteristics of goldenberry pomace oil (GPO) and goldenberry seed oil (GSO) were investigated. GPO and GSO contained high levels of unsaturated fatty acids (90.1% and 85.1%, respectively), and the major fatty acid was linoleic (62.0% and 72.8%, respectively). Additionally, GPO contained eleven triacylglycerol (TAG) species, three of which represented 82.7%, namely C54:6, C54:4 and C52:4, and trilinolein was the dominant one (35.5%). GSO contained nine TAG species, two of which represented 80.3%, namely C54:6 and C52:4, and trilinolein was dominant (53.3%). The DSC analysis of GPO and GSO revealed that three exothermal peaks were detected during cooling. Three endothermal peaks (one of which is exothermal for GSO) were detected during melting, and the most significant peaks occurred at low temperatures. FTIR spectra indicated that GPO and GSO did not contain peroxides or trans fatty acids, but they did contain low concentrations of free fatty acids.

Valorization of Almond (Prunus serotina) by Obtaining Bioactive Compounds

The Capulin almond is a seed of the Prunus serotina (var. capuli) that belongs to the Rosaceae family. In this study, the valorization of the Capulin almond was performed by extracting antioxidants contained in the shell, paste, and oil (extracted by manual cold pressing process) of Prunus serotina treated with methanol, ethanol, acetone, and acidified water (pH 4) in a ratio of 1:5 (w/v). Total phenols were performed using the Folin-Ciocalteu method and expressed as gallic acid equivalents (GAE), antioxidant activity was determined by ABTS and DPPH methods and expressed as Trolox equivalents (TE). Finally, the total flavonoids were determined using a catechin calibration curve and reported as catechin equivalents (CE). The highest extraction of total phenols in shell was obtained with methanol (1.65 mg GAE/g sample) and the lowest using acidified water (0.97 mg GAE/g sample). However, extraction with acidified water favored this process in the paste (1.42 mg GAE/g sample), while the use of solvents did not influence it significantly (0.72 to 0.79 mg GAE/g sample). Regarding the total flavonoids, the values for the shell, paste, and oil were of 0.37, 0.78, and 0.34 mg CE/g sample, respectively, while that corresponding to the antioxidant activity evaluated with ABTS and DPPH were of 1527.78, 1229.17, 18894.44 μM TE/g, and, 568.45, 562.5 and 4369.05 mM TE/g sample, respectively. Finally, our results suggest that by-products such as the shell, paste, and oil obtained from Prunus serotina (var. capuli) represent a potential alternative for the recovery of bioactive compounds with antioxidant activity such as phenolic compounds and flavonoids.

Comparative evaluation of the antioxidant, antimicrobial and nutritive properties of gluten-free flours

Gluten-free flours are interesting alternative to wheat flours. They could be by-products of oilseed processing, characterized by high content of bioactive compounds. Therefore the aim of the study was to determine the antioxidant, antimicrobial properties, amino acid and fatty acid profile of flours obtained as by-products from the oil industry. The highest total polyphenol content and antioxidant activity was found to have evening primrose flour. The widest spectrum of microbial growth inhibition was indicated for corn germ extract which showed no antimicrobial activity only against Bacillus subtilis. The highest protein content was found in pumpkin, peanut and almond flours (more than 50 g/100 g). The major abundant amino acids in all the analysed oilseed cake flours were aspartic acid, glutamic acid and arginine. The analysed gluten-free flours were found to be a good source of polyunsaturated fatty acids (PUFAs), which comprised mainly linoleic acid and α-linolenic acid, whereas the best source of PUFAs was evening primrose flour. The results suggest that the cold-pressed seed flours possess valuable chemical composition and may be considered for improvement of the nutritional properties of food products.

Influence of Pressure Extraction Systems on the Performance, Quality and Composition of Virgin Almond Oil and Defatted Flours

Almond is the most cultivated nut throughout the world. The oil content of almonds in most varieties exceeds 50%, which encourages the oil extraction to be used in gastronomy or in the cosmetic industry. The preferred system to extract almond oil is by means of pressure, which leads to obtaining a virgin oil ready for consumption. In this work, almond oil has been obtained using two pressure systems: screw press (SP) and hydraulic press (HP). The performance of both methods, as well as their influence on quality and composition characteristics of the almond oils obtained are analyzed from both a physical-chemical and sensory point of view. From an industry perspective, the highest oil yield is obtained with the SP when it operates at temperatures of 100–150 °C. Regarding the quality and chemical composition, the oils obtained by HP showed better quality indices, as they are subjected to a less aggressive treatment without influence of temperature, but lower content in total sterols. Fatty acid pattern, characterized by the predominance of unsaturated fatty acids (>90%), was not affected by the pressing system. The different operational conditions tested did not greatly affect the performance or composition of the oils obtained, but sensory tests showed two clearly differentiated products, the oil obtained by HP and that obtained by SP, according to consumer preferences. The defatted almond flours obtained as a by-product of the oil extraction process are characterized by a high content in protein and fiber, and a higher content in fat when the flour is produced from the pressing cake of HP.

The Potential of Grape Pomace Varieties as a Dietary Source of Pectic Substances

Grape pomace is one of the most abundant solid by-products generated during winemaking. A lot of products, such as ethanol, tartrates, citric acid, grape seed oil, hydrocolloids, bioactive compounds and dietary fiber are recovered from grape pomace. Grape pomace represents a major interest in the field of fiber extraction, especially pectin, as an alternative source to conventional ones, such as apple pomace and citrus peels, from which pectin is obtained by acid extraction and precipitation using alcohols. Understanding the structural and functional components of grape pomace will significantly aid in developing efficient extraction of pectin from unconventional sources. In recent years, natural biodegradable polymers, like pectin has invoked a big interest due to versatile properties and diverse applications in food industry and other fields. Thus, pectin extraction from grape pomace could afford a new reason for the decrease of environmental pollution and waste generation. This paper briefly describes the structure and composition of grape pomace of different varieties for the utilization of grape pomace as a source of pectin in food industry.

The Limonene Biorefinery: From Extractive Technologies to Its Catalytic Upgrading into p-Cymene

Limonene is a renewable cyclic monoterpene that is easily obtainable from citrus peel and it is commonly used as a nutraceutical ingredient, antibacterial, biopesticide and green extraction solvent as well as additive in healthcare, fragrance and food and beverage industries for its characteristic lemon-like smell. Indeed, the lack of toxicity makes limonene a promising bio-alternative for the development of a wide range of effective products in modern biorefineries. As a consequence, industrial demand largely exceeds supply by now. Limonene can be also used as starting substrate for the preparation of building block chemicals, including p-cymene that is an important intermediate in several industrial catalytic processes. In this contribution, after reviewing recent advances in the recovery of limonene from citrus peel and residues with particular attention to benign-by-design extractive processes, we focus on the latest results in its dehydrogenation to p-cymene via heterogeneous catalysis. Indeed, the latest reports evidence that the selective production of p-cymene still remains a scientific and technological challenge since, in order to drive the isomerization and dehydrogenation of limonene, an optimal balance between the catalyst nature/content and the reaction conditions is needed.

A step closer to circular bioeconomy for citrus peel waste: A review of yields and technologies for sustainable management of essential oils

This study presents a critical overview of reported essential oil (EO) extractions from citrus peel wastes (CPW), including harmonized data on the various citrus species and cultivars. Harmonization is vital to enable sustainable management practices. The review only includes eco-efficient extraction techniques. In total, the review contains 66 quantified examples using i) mechanical cold press ii) thermal extraction with water or steam media iii) thermal microwave-assisted extraction iv) other innovative methods (such as ultrasound). The technologies were assessed for their potential use in cascading production to achieve economies of scope, particularly considering the use of extraction residues for subsequent fermentation to produce various products from energy carriers to enzymes. Two techniques were found insufficient for direct use in fermentation. Cold press extracts an inadequate amount of EO (average yield 2.85% DW) to ensure suitable fermentation, while solvent extraction contaminates the residues for its subsequent use. Extractions using water media, such as hydrodistillation and microwave-assisted hydrodistillation (average EO yield 2.87% DW), are feasible for the liquid-based fermentation processes, such as submerged fermentation. Steam extraction is feasible for any type of fermentation. Our review highlighted solvent-free microwave extraction (average EO yield 5.29% DW) as the most effective method, which provides a high yield in a short extraction time. We also uncovered and discussed several inconsistencies in existing yields and energy consumption published data.

Grape (Vitis vinifera L.) Seed Oil: A Functional Food from the Winemaking Industry

Wine production is an ancient human activity that generates several by-products, which include some constituents known for their potential in health care and for their role in the food or cosmetic industries. Any variety of grape (Vitis vinifera L.) contains nutrients and bioactive compounds available from their juice or solid parts. Grape seed extract has demonstrated many activities in disease prevention, such as antioxidant effects, which make it a potential source of nutraceuticals. Grape seed is a remarkable winery industry by-product due to the bioactivity of its constituents. Methods for recovery of oil from grape seeds have evolved to improve both the quantity and quality of the yield. Both the lipophilic and hydrophilic chemicals present in the oil of V. vinifera L. make this wine by-product a source of natural nutraceuticals. Food and non-food industries are becoming novel targets of oil obtained from grape seeds given its various properties. This review focuses on the advantages of grape seed oil intake in our diet regarding its chemical composition in industries not related to wine production and the economic and environmental impact of oil production.

Biological properties of almond proteins produced by aqueous and enzyme-assisted aqueous extraction processes from almond cake

The almond cake is a protein-rich residue generated by the mechanical expression of the almond oil. The effects of the aqueous (AEP) and enzyme-assisted aqueous extraction processes (EAEP) on the biological properties of the almond cake protein were evaluated. Total phenolic content (TPC), antioxidant capacity, inhibitory effects against crucial enzymes related to metabolic syndrome, antimicrobial potential, and in vitro protein digestibility profile were assessed. EAEP provided the best results for antioxidant capacity by both ORAC (397.2 µmol TE per g) and ABTS (650.5 µmol TE per g) methods and also showed a high (~ 98%) potential for α-glucosidase inhibition. The AEP resulted in protein extracts with the highest lipase inhibition (~ 70%) in a dose-dependent way. Enzymatic kinetic analyses revealed that EAEP generated uncompetitive inhibitors against α-glucosidase, while EAEP, AEP, and HEX-AEP (used as control) generated the same kind of inhibitors against lipase. No protein extract was effective against any of the bacteria strains tested at antimicrobial assays. An in silico theoretical hydrolysis of amandin subunits corroborated with the results found for antioxidant capacity, enzyme inhibitory experiments, and antimicrobial activity. Digestibility results indicated that the digestive proteases used were efficient in hydrolyzing almond proteins, regardless of the extraction applied and that HEX-AEP presented the highest digestibility (85%). In summary, EAEP and AEP skim proteins have the potential to be used as a nutraceutical ingredient. The biological properties observed in these extracts could help mitigate the development of metabolic syndrome where EAEP and AEP skim proteins could be potentially used as a prophylactic therapy for diabetes and obesity, respectively.

Innovative and Conventional Valorizations of Grape Seeds from Winery By-Products as Sustainable Source of Lipophilic Antioxidants

The aim of this study was to valorize the oil recovery from red and white grape seeds (Vitis vinifera L.) that remains as by-product after the winemaking process. Oils were extracted by modern techniques, ultrasound assisted (UAE), microwave assisted (MAE) and supercritical fluid extraction (SFE), and compared to the Soxhlet extraction (SE). Firstly, SFE was optimized at different operating conditions: pressure (250-350 bar), temperature (40-60 °C), CO2 flow rate (0.2, 0.3 and 0.4 kg h-1), and particle size (315-800 µm and >800 µm). The highest extraction yields were achieved by SFE at the optimal conditions: 350 bar, 60 °C, 0.4 kg h-1. Afterwards, SFE was compared to SE, UAE and MAE with respect to oil extraction yields, and analyzed for fatty acid composition and antioxidant capacity. Considering the general classification of fatty acids, it was found that samples had high content of polyunsaturated fatty acids, regardless of extraction technology. Tocopherol content was significantly influenced by all extraction methods, whereas UAE and MAE resulted in extracts richer with lipophilic antioxidants. In conclusion, modern extractions that are suited for industrial applications had better performance as compared to SE, as judging by the oil yield and quality.

Aqueous and Enzymatic Extraction of Oil and Protein from Almond Cake: A Comparative Study

The almond cake is a protein- and oil-rich by-product of the mechanical expression of almond oil that has the potential to be used as a source of valuable proteins and lipids for food applications. The objectives of this study were to evaluate the individual and combined effects of solids-to-liquid ratio (SLR), reaction time, and enzyme use on oil and protein extraction yields from almond cake. A central composite rotatable design was employed to maximize the overall extractability and distribution of extracted components among the fractions generated by the aqueous (AEP) and enzyme-assisted aqueous extraction process (EAEP). Simultaneous extraction of oil and protein by the AEP was favored by the use of low SLR (1:12.82) and longer reaction times (2 h), where extraction yields of 48.2% and 70% were achieved, respectively. Increased use of enzyme (0.85%) in the EAEP resulted in higher oil (50%) and protein (75%) extraction yields in a shorter reaction time (1 h), compared with the AEP at the same reaction time (41.6% oil and 70% protein extraction). Overall, extraction conditions that favored oil and protein extraction also favored oil yield in the cream and protein yield in the skim. However, increased oil yield in the skim was observed at conditions where higher oil extraction was achieved. In addition to improving oil and protein extractability, the use of enzyme during the extraction resulted in the production of skim fractions with smaller and more soluble peptides at low pH (5.0), highlighting possible uses of the EAEP skim in food applications involving acidic pH. The implications of the use of enzyme during the extraction regarding the de-emulsification of the EAEP cream warrant further investigation.

Carrier oils in dermatology

Wounds are a common medical infliction. With the increase in microbial resistance and a shift of interest towards complementary medicines, essential oils have been shown to be beneficial in suppressing microbial growth. However, in practice, essential oils are more often diluted into a base due to the risk of topical adverse effects, such as dermatitis. There is a lack of collated evidence-based information on toxicity and efficacy of carrier oils. The current information on the subject matter is restricted to generic, aroma-therapeutic books and pamphlets, based on anecdotal evidence rather than an experimental approach. Therefore, this review aimed at identifying the recommended carrier oils used in dermatology and thereafter collating the scientific evidence to support the use of carrier oils together with essential oils recommended for dermatological use. Aloe vera gel had multiple studies demonstrating the ability to enhance wound healing; however, several other carrier oils have been largely neglected. It was observed that the extracts for certain plant species had been used to justify the use of the carrier oils of the same plant species. This is an inaccurate cross assumption due to the difference in chemical composition and biological activities. Lastly, despite these carrier oils being recommended as a base for essential oils, very little data was found on the interactive profile of the carrier oil with the essential oil. This review provides a platform for further studies, especially if essential oils are to receive credence in the scientific field.

Unsaponifiable fraction isolated from grape (Vitis vinifera L.) seed oil attenuates oxidative and inflammatory responses in human primary monocytes

Grape seed oil has significant potential for the management of inflammatory and oxidative conditions.

Phytochemical-rich foods inhibit the growth of pathogenic trichomonads

Background

Plants produce secondary metabolites that often possess widespread bioactivity, and are then known as phytochemicals. We previously determined that several phytochemical-rich food-derived preparations were active against pathogenic foodborne bacteria. Trichomonads produce disease (trichomoniasis) in humans and in certain animals. Trichomonads are increasingly becoming resistant to conventional modes of treatment. It is of interest to test bioactive, natural compounds for efficacy against these pathogens.

Methods

Using a cell assay, black tea, green tea, grape, pomegranate, and jujube extracts, as well as whole dried jujube were tested against three trichomonads: Trichomonas vaginalis strain G3 (found in humans), Tritrichomonas foetus strain D1 (found in cattle), and Tritrichomonas foetus-like organism strain C1 (found in cats). The most effective of the test substances was subsequently tested against two metronidazole-resistant Trichomonas vaginalis strains, and on normal mucosal flora.

Results

Black tea extract inhibited all the tested trichomonads, but was most effective against the T. vaginalis organisms. Inhibition by black tea was correlated with the total and individual theaflavin content of the two tea extracts determined by HPLC. Metronidazole-resistant Trichomonas vaginalis strains were also inhibited by the black tea extract. The response of the organisms to the remaining preparations was variable and unique. We observed no effect of the black tea extract on common normal flora bacteria.

Conclusions

The results suggest that the black tea, and to a lesser degree green tea, grape seed, and pomegranate extracts might present possible natural alternative therapeutic agents to treat Trichomonas vaginalis infections in humans and the related trichomonad infections in animals, without negatively affecting the normal flora.