Coupling of a streamlined solid-liquid extraction protocol with LC-ESI-MS/MS for the regular oversight of illegal bromate additive use: An accurate and sensitive determination method in preliminary and bakery products.

A reliable solid-liquid extraction protocol coupled with liquid chromatography-electrospray ionization-tandem mass spectrometry in the negative-ion mode was developed and validated for illegal bromate determination in preliminary and bakery products. Crude and dried-treated samples were directly extracted with acetonitrile-water (4:1, v/v). Bromate was determined using a Phenomenex Synergi™ Polar reversed-phase column and MS/MS under multiple reaction monitoring. The chosen solvent efficiently extracted bromate with all applied extraction-assisting techniques (p > 0.05). Although this assay avoids cleanup procedures, matrix effect of <-11% was achieved. Rapid bromate separation in only 8 min was attained by a reversed-phase column. In both commodities, linearity range, R2, recovery%, repeatability, intermediate precision, LOD and LOQ results were 0.05-100 ng mL-1, >0.9999, 88.6-103%, 2.93-9.80% and 9.64-10.10%, 0.015 µg kg-1 and 0.05 µg kg-1, respectively. Out of 288 tested real samples, 13.9% of violations were observed. This high-sensitivity protocol offers effective oversight and consumer protection.

Nopal cladode as a novel reinforcing and antioxidant agent for starch-based films: A comparison with lignin and propolis extract.

The potential use of nopal cladode flour (NC) as reinforcing/bioactive agent in cassava starch-based films was evaluated and compared with the use of propolis extract or lignin, which are commonly used for these purposes. Cassava starch-based films containing untreated NC (S-NC), NC treated at pH 12 (S-NC12), aqueous propolis extract at two different concentrations (SP1 or SP2), or lignin (S-L) were produced by the casting technique; glycerol was used as plasticizer. NC12 and NC affected the mechanical properties of the cassava starch-based film similarly as compared to propolis extract and lignin. Moreover, NC and NC12 had different performance as reinforcing and antioxidant agent in cassava starch-based film. Thus, S-NC12 film was more elongable (28.5 ± 6.5%), more hydrophobic (contact angle: 70.8° ± 0.1), less permeable to water vapor (0.8 ± 0.0 × 10-10 g·m-1·s-1·Pa-1) and had better antioxidant activity by ABTS•+ (44.70 ± 0.3 µM Trolox·g-1 of film) than the S-NC film. SEM and TGA analysis of films showed that NC12 was better incorporated into the cassava starch matrix than NC, lignin and propolis extract. Overall, nopal cladode flour has potential use in the production of active biodegradable packaging for the food preservation with high oxidation rate.

Improvement of Physico-chemical Properties of Arbequina Extra Virgin Olive Oil Enriched with ß-Carotene from Fungi.

Nowadays the consumption of essential carotenoids is reduced due to the lower intake of fruits and vegetables, being humans not capable of synthesizing these molecules. ß-carotene is one of the most important carotenoids possessing anti-oxidation, anti-inflammation and anti-cancer properties. The aim of this work consists of preparing virgin olive oils enriched in ß-carotene from fungi at different concentrations (0.041 and 0.082 mg/mL) in order to obtain new functional foods. Values of quality parameters (free acidity, peroxide value, coefficients of specific extinction and p-anisidine) have been obtained, showing that quality of olive oils was improved. Furthermore, the effect of ß-carotene was evaluated as possible oxidative stabilizer during microwave heating and ultra violet-light exposure of the oils. As expected, the enrichment process brought changes in olive oils color, turning them orange-reddish. The use of natural antioxidants, in particular ß-carotene could be an effective way to protect virgin olive oils from degradation and is a good strategy also to enhance the consumption of bioactive compounds improving olive oils shelf-life and nutritional value.

Characteristics and function of an extracellular polysaccharide from a green alga Parachlorella.

The green alga Parachlorella sp. BX1.5 is a new strain that can significantly coproduce lipids and polysaccharides, inside and outside the cells, respectively. This study aimed to investigate the characteristics and functional properties of the extracellular polysaccharide (EPS). Ethanol-extracted EPS from the cells grown in N-starved BG11 medium was found to be a novel acidic rhamnan of straight-chain type, with a high molecular mass of > 1.75 × 106 daltons. The water-soluble EPS exhibited high viscosity as sol, even at low concentrations, with 0.5 % EPS showing almost constant viscosity at 10-40 °C. Its addition to mayonnaise resulted in improved oil-off, suggesting its possible application as a thickener or food additive. Cells with added EPS were found to exhibit resistance to environmental stress conditions, such as heat, dryness, and decompression, and ultraviolet rays. Based on these rheological and biological effects, its unique properties with respect to biorefinery have been discussed here.

Oleamide in Ipomoea and Dillenia Species and Inflammatory Activity Investigated through Ion Channel Inhibition.

BACKGROUND: Oleamide is an essential substance for human health. So, the plants with high oleamide content are great sources for health care products. OBJECTIVE: This study is conducted to investigate the quality of oleamide in plants and test the bioactivity in the selected two studied species. METHODS: The three Ipomoea and five Dillenia species including Ipomoea alba, Ipomoea aquatica and Ipomoea pes-caprae, and Dillenia indica, Dillenia obovata, Dillenia ovata, Dillenia parviflora and Dillenia pentagyna were investigated for the quantity of oleamide by high-performance liquid chromatography. The biological activity test was conducted on the powder formulation of the chosen plants, Dillenia ovata and Dillenia parviflora at a ratio of 30:70, for anti-inflammatory activity ex vivo on a panel of molecular targets through ion channel inhibition including voltage-gated sodium channel, voltage-gated potassium channel, and the cardiac ion as human ether-a-go-go related gene. RESULTS: The results showed that the leaf extracts of I. aquatica and D. ovata gave the highest and subsequent oleamide quantity i.e. 7.52 and 5.17 mg/g, respectively. Out of the Dillenia formulation which contained various compounds, oleamide showed the highest percentages of inhibition at 8.0-20.0%, and 6.2-14.2% in voltage-gated sodium channel, and voltage-gated potassium channel which had slightly lower values than the oleamide standard, and no effect as 0.0% value inhibition in the cardiac ion channel. CONCLUSION: The Dillenia formulation exhibits anti-inflammatory activity without affecting the heart. Accordingly, the three studied Ipomoea and three studied Dillenia species may be used for the same activity as a single component or formulation with effective solvent for disease treatments.

Functional compounds from olive pomace to obtain high-added value foods - a review.

Olive pomace, the solid by-product from virgin olive oil extraction, constitutes a remarkable source of functional compounds and has been exploited by several authors to formulate high value-added foods and, consequently, to foster the sustainability of the olive-oil chain. In this framework, the aim of the present review was to summarize the results on the application of functional compounds from olive pomace in food products. Phenolic-rich extracts from olive pomace were added to vegetable oils, fish burgers, fermented milk, and in the edible coating of fruit, to take advantage of their antioxidant and antimicrobial effects. Olive pomace was also used directly in the formulation of pasta and baked goods, by exploiting polyunsaturated fatty acids, phenolic compounds, and dietary fiber to obtain high value-added healthy foods and / or to extend their shelf-life. With the same scope, olive pomace was also added to animal feeds, providing healthy, improved animal products. Different authors used olive pomace to produce biodegradable materials and / or active packaging able to increase the content of bioactive compounds and the oxidative stability of foods. Overall, the results highlighted, in most cases, the effectiveness of the addition of olive pomace-derived functional compounds in improving nutritional value, quality, and / or the shelf-life of foods. However, the direct addition of olive pomace was found to be more challenging, especially due to alterations in the sensory and textural features of food. © 2020 Society of Chemical Industry.

Optimized pulsed electric field-assisted extraction of biosurfactants from Chubak (Acanthophyllum squarrosum) root and application in ice cream.

BACKGROUND: In this study, a face-centered central composite design was applied to optimize pulsed electric field parameters (voltage: 1, 4, 7 kV cm-1 ; pulse number: 10, 65, 120) for the extraction of natural saponins from Chubak root. Data analysis showed that increasing the voltage from 1 to 4 kV cm-1 and pulse number from 10 to 65 increased foaming ability (FA) and emulsion stability, and decreased foam density (FD), foam stability (FS) and lightness, due to the improved extraction of saponins. RESULTS: Whereas, an opposite trend was observed for FA, FD and FS on increasing the voltage from 4 to 7 kV cm-1 as a result of more impurities being extracted. Furthermore, the Chubak root extract (CRE) (0, 1.5, 3.0 and 4.5 g kg-1 ) obtained under the optimized conditions (voltage of 6.4 kV cm-1 and pulse number of 80) was used in ice cream formulation because of its ability to reduce surface tension. Based on the results, the samples containing higher amounts of CRE showed higher viscosity, consistency coefficient, overrun, melting resistance and creaminess, as well as lower values of flow behavior index, hardness, adhesiveness, coarseness and coldness. This could be related to the increased water retention, improved whipping ability, greater fat destabilization and smaller ice crystals. Although more bitterness was perceived as a result of an increase in the level of CRE, it had no negative effect on the overall acceptance assessed by trained sensory panelists. CONCLUSIONS: The results of this study briefly support the conclusion that CRE has a very high potential for use as a foaming, emulsifying and stabilizing agent to improve the quality of ice cream. © 2020 Society of Chemical Industry.

Multi-response optimization of alginate bleaching technology extracted from brown seaweeds by an eco-friendly agent.

Alginate only finds industrial applicability after undergoing a bleaching process to improve its visual appearance. Box-Behnken Design was used to optimize bleaching parameters (time, oxygen flow and temperature) for sodium alginate (SA) extracted from seaweeds using ozone as the bleaching agent. The optimal conditions (oxygen flow 2 L/min for 35 min at 25 °C) resulted in an ozone-bleached SA with a mannuronic/guluronic acids ratio of 0.70, viscosity-average molecular weight of 66.30 kDa and dynamic viscosity of 1.39 mPa.s, aligned to strong and brittle gels formation, which are potentially suitable for hydrogels and bioink application. Results indicated that ozonation caused depolymerization of the SA chain. Colorimetric parameters showed that ozone has a great bleaching efficacy. The bleached sample presented high antioxidant capacity, highlighting that discoloration by ozone might have minimal effects on the bioactive compounds which are valuable ingredients for food-based products.

Eurycoma longifolia-Infused Coffee-An Oral Toxicity Study.

Coffee infused with the additive Eurycoma longifolia, also known as Tongkat ali (TA), has become widely available in the Malaysian market. Safety evaluations for consumption of the products have been called for due to the herbal addition. This study investigates the acute, subacute and chronic effects of a commercial TA coffee in Sprague Dawley rats when given in a single, repeated and prolonged dosage. The dosages of 0.005, 0.05, 0.30 and 2 g/kg body weight (BW) were used in the acute study and 0.14, 0.29 and 1 g/kg BW were used in the repeated dose studies. The in-life parameters measured were food and water intake, body weight and clinical observations. Blood were collected for hematology and clinical biochemistry analyses. All animals were subjected to full necropsies. Non-toxicity-related changes were observed in the food and water consumption parameters. Body weight showed normal increments and none of the animals had any clinical signs of toxicity. Microscopically assessed organ tissues did not reveal any abnormalities. There was significant decrease of platelet count in all the chronic study male treated groups. Significant elevation of renal profile parameters in both gender groups given 0.29 g/kg BW, along with liver and lipid profile elevation in some female groups of the chronic study were noted. No dose-dependent relationship was apparent in the dosage range tested, though these changes may suggest an initial safety indication to the TA coffee. The study concludes that the no observed adverse effect level (NOAEL) for this commercial TA coffee was 1 g/kg BW.

Antioxidant activities of mamao luang (Antidesma thwaitesianum Müll. Arg.) fruit: Extraction and application in raw chicken patties.

Extraction of mamao luang (hereafter called mamao) with different solvents and varying solid to liquid (S:L) ratio was conducted to verify its antioxidant activities. Total phenolic content (TPC), total flavonoid content, total monomeric anthocyanin content, and antioxidant activities, namely, 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity and ferric reducing antioxidant power (FRAP) of the unrefined extracts, were analyzed. The extraction with 70% acetone and 70% methanol and the S:L ratio of 1:30 seemed to be more appropriate and gave significantly (P < 0.05) higher values of the previously mentioned properties. Whole ground fruits were then incorporated into the blended chicken patties to compare their antioxidant and antimicrobial properties with butylated hydroxyanisole (BHA). During refrigeration storage of 20 days, the highest level (1,000 mg TPC/kg meat) could retard lipid oxidation relatively comparable to the efficiency of BHA (200 ppm). However, when microbiological aspect was considered together, a limited storage of 12 days was consequently suggested. PRACTICAL APPLICATION: Mamao fruit is a splendid source of phenolic compounds. The antioxidant properties have been demonstrated using DPPH and FRAP assay. The suitable type of solvent and S:L ratio were provided for the extraction. Our findings have shown that addition of mamao, a source of natural antioxidants, especially at the highest level increased oxidative stability of chicken patties. The research outcomes identify the potential bioactive compound and provide beneficial information related to the feasibility of incorporation of mamao phenolics as antioxidant agents in suitable food matrices. However, further investigation is still required for successful application in meat and meat products.

Vegetable lecithins: A review of their compositional diversity, impact on lipid metabolism and potential in cardiometabolic disease prevention.

Vegetable lecithins, widely used in the food industry as emulsifiers, are a mixture of naturally occurring lipids containing more than 50% of phospholipids (PL). PL exert numerous important physiological effects. Their amphiphilic nature notably enables them to stabilise endogenous lipid droplets, conferring them an important role in lipoprotein transport, functionality and metabolism. In addition, beneficial effects of dietary lecithin on metabolic disorders have been reported since the 1990s. This review attempts to summarize the effects of various vegetable lecithins on lipid and lipoprotein metabolism, as well as their potential application in the treatment of dyslipidemia associated with metabolic disorders. Despite controversial data concerning the impact of vegetable lecithins on lipid digestion and intestinal absorption, the beneficial effect of lecithin supplementation on plasma and hepatic lipoprotein and cholesterol levels is unequivocal. This is especially true in hyperlipidemic patients. Furthermore, the immense compositional diversity of vegetable lecithins endows them with a vast range of biochemical and biological properties, which remain to be explored in detail. Data on the effects of vegetable lecithins alternative to soybean, both as supplements and as ingredients in different foods, is undoubtedly lacking. Given the exponential demand for vegetable products alternative to those of animal origin, it is of primordial importance that future research is undertaken in order to elucidate the mechanisms by which individual fatty acids and PL from various vegetable lecithins modulate lipid metabolism. The extent to which they may influence parameters associated with metabolic disorders, such as intestinal integrity, low-grade inflammation and gut microbiota must also be assessed.

Chia seed mucilage - a vegan thickener: isolation, tailoring viscoelasticity and rehydration.

Chia seeds and their mucilage gels provide a nutritionally and functionally promising ingredient for the food and pharmaceutical industry. Application and utilization of the gel remain limited due to the tightly adhesion of the mucilage to the seeds, which affects the organoleptic properties, control of concentration and structuring possibilities. To exploit the full potential of chia mucilage gels as a functional ingredient calls for separation and purification of the gel. Herein, the gel was extracted by centrifugation and characterized rheologically and microscopically to link the viscoelastic properties to the structural properties. Subsequently, the gel was dried employing three different methods for facilitated storage and prolonged shelf life. The dried gels were readily soluble and its viscoelastic properties were fully regenerated upon rehydration demonstrating its potential to envisage industrial applications. The viscoelastic chia mucilage demonstrated shear-thinning behavior with complete relaxation upon stress removal. The gel's elasticity was enhanced with increasing mucilage concentration resulting in a highly tunable system. The extractable and rehydratable functional chia gel is a viable candidate as additive for the development of products requiring specific viscoelastic properties. Addition of the gel enhances the nutritional profile without interfering with the organoleptic properties.

Red Chicory (Cichorium intybus) Extract Rich in Anthocyanins: Chemical Stability, Antioxidant Activity, and Antiproliferative Activity In Vitro.

Red chicory leaves are appreciated sensorially and their constituents contain bioactive properties. The objectives of this study were as follows: to use an experimental design to extract anthocyanins from red chicory in aqueous solution at pH 2.5; to determine the stability of the extracts in relation to temperature and pH; and to evaluate the antioxidant activity and in vitro cytotoxic effect of the lyophilized and purified extracts. The best extraction conditions for the bioactive compounds from red chicory were a temperature of 64.2 °C for 25 min; the anthocyanin content was 73.53 ± 0.13 mg per 100 g fresh weight basis sample. The EC50 (Half maximal effective concentration) value for the antioxidant activity assay in relation to DPPH (2,2-diphenyl-1-picrylhydrazyl) with optimized extract was 0.363, which corresponds to a concentration of 39.171 µmol/L of anthocyanins. The activation energy for the degradation reaction of the anthocyanins from the red chicory extract was 84.88 kJ/mol. The optimized extract, which was rich in anthocyanins, showed chemical and biological antioxidant activity (protection against erythrocyte hemolysis) and inhibited lipid peroxidation in vitro. The Cichorium intybus L. extracts interfered on the levels of reactive oxygen species generation and the crude extract did not present procarcinogenic effect. PRACTICAL APPLICATION: Red chicory is basically consumed as a part of traditional dishes worldwide. Here, we developed a process to extract and purify the anthocyanins from Cichorium intybus leaves and test the extracts in terms of the chemical composition, thermal stability, antioxidant activity, and antiproliferative effects. The anthocyanin-rich extract presented antioxidant activity in chemical and biological assays and low cytotoxicity and cytoprotective effects in relation to HepG2, HCT8, and Caco-2 cell lines. Additionally, the red chicory extract protected human erythrocytes against hemolysis. This extract may be used as a natural colorant/antioxidant in foods.

Physiochemical Properties and Functional Characteristics of Protein Isolates from the Scallop (Patinopecten yessoensis) Gonad.

Protein isolates were recovered from scallop (Patinopecten yessoensis) gonads to develop a novel functional matrix by investigating their physiochemical and functional properties. Scallop gonad protein isolates (SGPIs) were prepared from degreased scallop gonads (DSGs) by an alkali extraction and isoelectric solubilization/precipitation (ISP) process. The protein compositions of the SGPIs were mainly vitellogenin and beta-actin with molecular weights of 266 and 42 kDa, respectively, as determined using Nano-liquid chromatography-mass/mass (Nano-LC-MS/MS). After the ISP process, the protein solubility of the SGPIs was significantly improved, and the surface hydrophobicity of SGPIs intensely increased by 1.1-fold, which were attributed to the exposure of aromatic residues such as phenylalanine, tyrosine, and tryptophan. However, the content of total/reactive sulfhydryl in SGPIs was decreased compared with that of DSGs. Meanwhile, the ISP process caused partial protein unfolding, as indicated by circular dichroism analysis, which exhibited a remarkable rise in the ß-sheet content with a parallel decline in the α-helix and random coil contents (P < 0.05). SGPIs exhibited a better oil absorption capacity and foaming property than both DSGs and soybean protein isolates (SPIs). Moreover, the emulsifying capacity of SGPIs was greatly enhanced by the ISP process, which was superior to the effect of commercial SPIs and was ascribed to its favorable solubility as well as surface characteristics. PRACTICAL APPLICATION: During the processing of scallop (Patinopecten yessoensis) adductors, scallop gonad, a high-protein part, is usually discarded as processing by-products despite its edibility. In recent years, scallop gonads are regarded as good sources to develop protein matrices due to their high protein content and numerous nutrients. In this study, scallop gonad protein isolates (SGPIs) were isolated by isoelectric solubilization/precipitation (ISP) process. The preferable solubility, foaming property coupled with high emulsifying property of SGPIs indicated that the SGPIs could be potentially utilized as a good protein emulsifier and additives in production of kamaboko gels, hamburger patties, sausages, and pet foods.

Betanin, a Natural Food Additive: Stability, Bioavailability, Antioxidant and Preservative Ability Assessments.

Betanin is the only betalain approved for use in food and pharmaceutical products as a natural red colorant. However, the antioxidant power and health-promoting properties of this pigment have been disregarded, perhaps due to the difficulty in obtaining a stable chemical compound, which impairs its absorption and metabolism evaluation. Herein, betanin was purified by semi-preparative HPLC-LC/MS and identified by LC-ESI(+)-MS/MS as the pseudomolecular ion m/z 551.16. Betanin showed significant stability up to -30 °C and mild stability at chilling temperature. The stability and antioxidant ability of this compound were assessed during a human digestion simulation and ex vivo colon fermentation. Half of the betanin amount was recovered in the small intestine digestive fluid and no traces were found after colon fermentation. Betanin high antioxidant ability was retained even after simulated small intestine digestion. Betanin, besides displaying an inherent colorant capacity, was equally effective as a natural antioxidant displaying peroxy-radical scavenger ability in pork meat. Betanin should be considered a multi-functional molecule able to confer an attractive color to frozen or refrigerated foods, but with the capacity to avoid lipid oxidation, thereby preserving food quality. Long-term supplementation by beetroot, a rich source of betanin, should be stimulated to protect organisms against oxidative stress.

Construction and application of a Xanthomonas campestris CGMCC15155 strain that produces white xanthan gum.

In the industrial production of xanthan gum using Xanthomonas campestris CGMCC15155, large amounts of ethanol are required to extract xanthan gum from the fermentation broth and remove xanthomonadin impurities. To reduce the amount of ethanol and the overall production cost of xanthan gum, a xanthomonadin-deficient strain of CGMCC15155 was constructed by inserting the Vitreoscilla globin (vgb) gene, under the control of the LacZ promoter, into the region of the pigA gene, which is involved in xanthomonadin synthesis. The insertion of vgb inactivated pigA, resulting in the production of white xanthan gum. The lack of xanthomonadins resulted in a decreased yield of xanthan gum. However, the expression product of vgb gene, VHb, could increase the metabolism of X. campestris, which allowed the production of xanthan gum to reach wild-type levels in the engineered strain. The yield, molecular weight, and rheological properties of the xanthan gum synthesized by the engineered and wild-type bacteria were essentially the same. When the same volume of ethanol was used, the whiteness values of the xanthan gum extracted from engineered and wild-type bacteria were 65.20 and 38.17, respectively. To extract xanthan gum with the same whiteness, three and seven times the fermentation volume of ethanol was required for the engineered and wild-type strains, respectively. Thus, the engineered train reduced the requirement for ethanol in xanthan gum production by 133.3%. The results demonstrated that the engineered bacteria used less ethanol, thus reducing the downstream processing cost in xanthan gum production.

Simultaneous extraction and analysis of preservatives and artificial sweeteners in juices by salting out liquid-liquid extraction method prior to ultra-high performance liquid chromatography.

A novel and fast salting out liquid-liquid extraction method was developed for simultaneous determination of food additives with different polarities in juices. Chromatographic separation was achieved in less than 6 min using Acquity UPLC BEH C 18 (100 mm × 2.1 mm d.i. × 1.7 µm) column with ammonium acetate with 0.01% of trifluoroacetic acid as eluent A and acetonitrile as eluent B at a flow rate of 0.2 mL min-1. The main factors affecting the extraction efficiency were optimized. The method was validated applying accuracy profile based on total error. The extraction recoveries ranged from 84.97 to 122%. Relative standard deviation ranged from 1.24 to 7.99% for intraday assay and from 1.69 to 9.16% for intermediate precision. The limits of detection for five food additives were from 0.3 to 1.42 µg mL-1. The method was successfully applied to 47 samples of juices from nine brands.

Covalent organic framework TpPa-1 as stationary phase for capillary electrochromatographic separation of drugs and food additives.

Because of unique properties like permanent porosity, low density and large surface area, covalent organic frameworks are attractive microporous materials as stationary phase for CEC. Among them, COF-TpPa-1 possesses extraordinary chemical stability and common features of covalent organic frameworks. So, COF-TpPa-1 could be a promising material as stationary phase to enhance separation selectivity and tolerate the acid or alkaline electrochromatographic separation conditions. Here, we report the preparation of COF-TpPa-1 modified capillary column by in situ growth for electrochromatographic separation. The immobilization of COF-TpPa-1 on the inner wall of capillary column was confirmed by Fourier transform infrared spectroscopy, scanning electron microscopy and X-ray diffraction. The fabricated COF-TpPa-1 modified capillary column indicated good resolution for the separation of neutral analytes, nonsteroidal anti-inflammatory drugs and food additives in open-tubular CEC mode. Compared with bare capillary column, the COF-TpPa-1 modified capillary column improved separation selectivity remarkably for tested analytes, including hydrophobic, π-π and hydrogen bond interactions. Besides, the prepared capillary column showed excellent repeatability and stability. The intraday, interday and column-to-column relative standard deviations of migration time for neutral analytes were less than 3.54%. This work shows enamine-linked covalent organic frameworks have great potential as stationary phases in CEC.

Layer-by-Layer Alginate and Fungal Chitosan Based Edible Coatings Applied to Fruit Bars.

Food waste is currently being generated at an increasing rate. One proposed solution would be to convert it to biopolymers for industrial applications. We recovered chitin from mushroom waste and converted it to chitosan to produce edible coatings. We then used layer-by-layer (LbL) electrostatic deposition of the polycation chitosan and the polyanion alginate to coat fruit bars enriched with ascorbic acid. The performance of the LbL coatings was compared with those containing single layers of fungal chitosan, animal origin chitosan and alginate. Bars containing alginate-chitosan LbL coatings showed increased ascorbic acid content, antioxidant capacity, firmness and fungal growth prevention during storage. Also, the origin of the chitosan did not affect the properties of the coatings. PRACTICAL APPLICATION: Mushroom stalk bases could be an alternative source for isolating chitosan with similar properties to animal-based chitosan. Also, layer-by-layer assembly is a cheap, simple method that can improve the quality and safety of fruit bars.

Maximizing carotenoid extraction from microalgae used as food additives and determined by liquid chromatography (HPLC).

Microalgae are an interesting source of natural pigments that have valuable applications. However, further research is necessary to develop processes that allow us to achieve high levels of carotenoid recovery while avoiding degradation. This work presents a comprehensive study on the recovery of carotenoids from several microalgae genera, optimizing carotenoid extraction using alkaline saponification at various temperatures and KOH concentrations. Results show that I. galbana requires a temperature of 60 °C and <10% KOH, N. gaditana and K. veneficum require 60 °C and no saponification, P. reticulatum requires 40 °C and 10% KOH, T. suecica and H. pluvialis require 25 °C and 40% KOH while C. sp. and S. almeriensis require 80 °C and 40% KOH. The influence of the solvent on carotenoid recovery was also studied. In general terms, an ethanol:hexane:water (77:17:6 v/v/v) mixture results in good yields.