Identification of lentils (Lens culinaris Medik) from Eglouvi (Lefkada, Greece) based on rare earth elements profile combined with chemometrics.

An analytical approach has been developed to verify the authenticity of premium lentils originating from Eglouvi, Lefkada, Greece. The method relies on the digestion of samples followed by the analysis of their rare earth elements (REEs) content. Lentils originating from Eglouvi exhibit higher content in most REEs compared to lentils from other regions as well as distinct Sc/Y and Sc/Yb concentration ratios. Principal component analysis effectively segregates "Eglouvi" lentils into a distinct cluster. Soft Independent Modelling of Class Analogy (SIMCA) successfully models "Eglouvi" lentils. Significant enhancement in model specificity was achieved upon inclusion of Sc/Y and Sc/Yb concentration ratios as additional variables. The model is capable of detecting adulteration in blends of Eglouvi lentils, with a minimum rejection threshold of 4.6% w/w for Greek lentil adulterants and 6.0% w/w for imported lentil adulterants.

Comparative Study of Novel Methods for Olive Leaf Phenolic Compound Extraction Using NADES as Solvents.

Natural deep eutectic solvents (NADES) composed of choline chloride with maltose (CMA), glycerol (CGL), citric (CCA) and lactic acid (CLA) combined with microwave (MAE), ultrasound (UAE), homogenate (HAE) and high hydrostatic pressure (HHPAE)-assisted extraction methods were applied to recover and compare olive leaf phenolic compounds. The resultant extracts were evaluated for their total phenol content (TPC), phenolic profile and antioxidant activity and compared with those of water and ethanol:water 70% v/v extracts. HAE was proven to be the most efficient method for the recovery of olive leaf phenolic compounds. The highest TPC (55.12 ± 1.08 mg GAE/g d.w.) was found in CCA extracts after HAE at 60 °C and 12,000 rpm, and the maximum antioxidant activity (3.32 ± 0.39 g d.w./g DPPH) was found in CGL extracts after UAE at 60 °C for 30 min. The TPCs of ethanol extracts were found to be higher than those of NADES extracts in most cases. The predominant phenolic compounds in the extracts were oleuropein, hydrohytyrosol and rutin.

Encapsulation of Bifidobacterium animalis subsp. lactis Through Emulsification Coupled with External Gelation for the Development of Synbiotic Systems.

Aim of this work was the development of integrated and complex encapsulating systems that will provide more efficient protection to the probiotic strain Bifidobacterium animalis subsp. lactis (BB-12) in comparison to the conventional plain alginate beads. Within the scope of this study, the encapsulation of BB-12 through emulsification followed by external gelation was performed. For this purpose, a variety of alginate-based blends, composed of conventional and novel materials, were used. The results demonstrated that alginate beads incorporating 1% carrageenan or 2% nanocrystalline cellulose provided great protection to the viability of the probiotic bacteria during refrigerated storage (survival rates of 50.3% and 51.1%, respectively), as well as in vitro simulation of the gastrointestinal tract (survival rates of 38.7 and 42.0%, respectively). The incorporation of glycerol into the formulation of the beads improved the protective efficiency of the beads to the BB-12 cells during frozen storage, increasing significantly their viability compared to the plain alginate beads. Beads made of milk, alginate 1%, glucose 5%, and inulin 2% provided the best results in all cases. The microstructure of beads was assessed through SEM analysis and showed absence of free bacteria on the surface of the produced beads. Consequently, the encapsulation of BB-12 through emulsification in a complex encapsulating system was proved successful and effective.

Addition of Silver Nanoparticles to Composite Edible Films and Coatings to Enhance Their Antimicrobial Activity and Application to Cherry Preservation.

The aim of this study was to examine the potential enhancement of the antimicrobial activity of edible films, composed of (i) chitosan (CH), cellulose nanocrystals (CNC) and beta-cyclodextrin (CD) (50%-37.5%-12.5%) and (ii) hydroxypropyl methylcellulose (HPMC), cellulose nanocrystals (CNC) and beta-cyclodextrin (CD) (50%-37.5%-12.5%), with silver nanoparticle (AgNP) incorporationat levels 5, 10 and 15% v/v. According to the results, the AgNP addition led to very high antimicrobial activity of both films, reducing by more than 96% the microbial growth of the Gram-negative bacterium Escherichia coli (E. coli) in all cases. On the other hand, by adding AgNPs to films, their thickness as well as oxygen and water vapor permeability decreased, while their transparency increased. Furthermore, the contribution of these specific edible films to preserve cherries under cold storage was investigated. All edible coatings resulted in an improvement of the fruit properties under consideration, and especially the color difference, hardness and total microbial load.

Edible films and coatings: properties for the selection of the components, evolution through composites and nanomaterials, and safety issues.

Edible films and coatings, despite their practical applications, have only entered the food industry in the last decade. Their main functions are to protect the food products from mechanical damage and from physical, chemical and microbiological deteriorative changes. The ingredients used for their formation are polysaccharides, proteins and lipids, in individual or combined formulations. The edible films and coatings have already been applied on various food products, such as fruits, vegetables, meat products, seafood products, cheese, baked products and deep fat fried products. The techniques for their application on foods are of particular interest. Nowadays, composite edible films and coatings are also being studied, based on combinations of the properties of individual components. In addition to conventional materials, new ones, such as nanomaterials, are being investigated, aiming to enhance the resulting properties. However, before the incorporation of new materials to films and coatings, they must be thoroughly checked according to the legislation, to assure their lawful use. This review covers the recent developments on the edible films and coatings area in terms of the contribution of novel constituting materials to the improvement of their properties.

Novel Processes for the Extraction of Phenolic Compounds from Olive Pomace and Their Protection by Encapsulation.

Olive pomace, the solid by-product derived from olive oil production consists of a high concentration of bioactive compounds with antioxidant activity, such as phenolic compounds, and their recovery by applying innovative techniques is a great opportunity and challenge for the olive oil industry. This study aimed to point out a new approach for the integrated valorization of olive pomace by extracting the phenolic compounds and protecting them by encapsulation or incorporation in nanoemulsions. Innovative assisted extraction methods were evaluated such as microwave (MAE), homogenization (HAE), ultrasound (UAE), and high hydrostatic pressure (HHPAE) using various solvent systems including ethanol, methanol, and natural deep eutectic solvents (NADESs). The best extraction efficiency of phenolic compounds was achieved by using NADES as extraction solvent and in particular the mixture choline chloride-caffeic acid (CCA) and choline chloride-lactic acid (CLA); by HAE at 60 °C/12,000 rpm and UAE at 60 °C, the total phenolic content (TPC) of extracts was 34.08 mg gallic acid (GA)/g dw and 20.14 mg GA/g dw for CCA, and by MAE at 60 °C and HHPAE at 600 MPa/10 min, the TPC was 29.57 mg GA/g dw and 25.96 mg GA/g dw for CLA. HAE proved to be the best method for the extraction of phenolic compounds from olive pomace. Microencapsulation and nanoemulsion formulations were also reviewed for the protection of the phenolic compounds extracted from olive pomace. Both encapsulation techniques exhibited satisfactory results in terms of encapsulation stability. Thus, they can be proposed as an excellent technique to incorporate phenolic compounds into food products in order to enhance both their antioxidative stability and nutritional value.

A review of the microencapsulation techniques for the incorporation of probiotic bacteria in functional foods.

Probiotic strains are claimed to confer health benefits to human organisms when consumed in adequate amounts. Thus, over the last decades there has been an increased interest in the production of functional foods containing probiotic bacteria. However, in order to display optimal probiotic functionality, these bacteria should survive through the gastrointestinal tract (GI) in high populations, reaching 106-107cfu (colony-forming unit)/g or mL at the end of product's shelf life. The food products that can be used as probiotic bacteria carriers exhibit limitations concerning the viability of the cells, associated with parameters such as the acidity of the food matrices or their processing and storage conditions. Moreover, the acid environment of the GI system may be crucial for their survival. Thus, techniques such as microencapsulation and enrichment with prebiotic substances are proposed for their protection. Aim of this review is to present the bacterial strains exhibiting probiotic properties, the microencapsulation techniques which are applied for their protection, as well as their advantages and disadvantages. Finally, the characteristics of the most important food products that have been used as possible matrices for microencapsulated probiotic cells are described.

Adsorption of indigo carmine on functional chitosan and ß-cyclodextrin/chitosan beads: Equilibrium, kinetics and mechanism studies.

The present study was designed to produce novel cross-linked Chitosan and Chitosan/ß-Cyclodextrin beads and study the adsorption of Indigo Carmine. Both adsorbents were characterized by SEM and FTIR techniques. Batch experiments were conducted in order to evaluate the effect of initial adsorbent's concentration, dye's initial concentration, initial pH and temperature. In all cases Chitosan/ß-Cyclodextrin crosslinked beads exhibited higher removal efficiency of Indigo Carmine. Higher removal rates of Indigo Carmine were observed at low values of dye's initial concentration, pH and temperature, and high concentrations of adsorbent. The equilibrium adsorption data were a good fit for both Langmuir and Freundlich models and maximum adsorption capacity was 500.0 and 1000.0 mgIC/gadsorbent for Chitosan and Chitosan/ß-Cyclodextrin crosslinked beads, respectively. Adsorption of Indigo Carmine was found to follow the pseudo-second order. The negative values of ΔGo, ΔHo and ΔSo indicate that the adsorption process is exothermic, spontaneous and favorable at low temperatures.

The properties and breadmaking potential of freshly baked and frozen bakery products during partial replacement of wheat flour with spelt flour.

The aim of this work was the evaluation of the breadmaking potential of spelt flour when combined with wheat flour in various proportions, both in freshly baked and frozen form, and determine the optimal ratio for products with satisfactory quality characteristics. Freshly baked samples were prepared using different spelt-wheat flour mixtures ranging from 0 to 100% spelt at 10% intervals, while batches containing 0, 30, 50, 80, and 100% spelt were prepared in the case of frozen dough samples. The characteristics of the final baked products (dough volume expansion, specific volume, crust and crumb color, hardness, and water activity) were evaluated. Results showed that spelt flour proportions up to 20% provide bread with quality and sensory characteristics similar to wheat, while proportions higher than 70% lead to products with inferior properties. Therefore, samples with spelt content between 30 and 60%, although slightly degraded, remained highly acceptable.

Comparison of spray, freeze and oven drying as a means of reducing bitter aftertaste of steviol glycosides (derived from Stevia rebaudiana Bertoni plant)--Evaluation of the final products.

The aim of this study was to encapsulate the steviol glycosides (SGs) by spray, freeze and vacuum oven drying in order to minimise the bitter aftertaste of the SGs, as well as to improve their properties. Different ratios of maltodextrin to inulin as agents were examined, 80:20, 75:25, 70:30, 65:35 and 60:40, while the concentration of SGs in total solids was maintained constant at 2.5%. The obtained SGs products were evaluated by microencapsulation efficiency (MEE%), hygroscopicity, solubility, moisture content, structure (SEM, XRD), FT-IR and sensory properties. Significant differences in MEE%, moisture content, structure and solubility values were observed depending on the applied drying method. The reduced hygroscopicity values (20.26-26.67 g H2O/100g dry weight) contribute to improved stability. The FT-IR technique confirmed that SGs maintained their chemical integrity during the applied drying processes. The spray dried SGs products presented the best physicochemical characteristics and the most appealing sensorial ones.

Addition of Vital Wheat Gluten to Enhance the Quality Characteristics of Frozen Dough Products.

The aim of this study was to enhance the quality and sensory characteristics of bread made from frozen dough. Both white and whole-wheat flour were used. In order to improve dough strength and stability during frozen storage, samples were supplemented with vital wheat gluten at the levels of 2%, 4%, 5%, and 6% of flour weight. The characteristics of baked samples were determined through weight loss, specific volume, crust, and crumb color, texture, and sensory evaluation. Dough behavior at sub-zero temperatures was further examined for control samples and samples with 6% gluten using Differential Scanning Calorimetry (DSC), while their low molecular sugar content (fructose, glucose, sucrose) was measured using High Pressure Liquid Chromatography (HPLC), as it can be associated with yeast viability and dough freezing point depression. The most stable samples were those with 4% and 6% gluten (for white flour) and those with 4% and 5% gluten (for whole-wheat flour). Gluten addition raised the freezing point of dough samples and preserved low molecular sugar generation after prolonged storage.

Saffron and beetroot extracts encapsulated in maltodextrin, gum Arabic, modified starch and chitosan: Incorporation in a chewing gum system.

Maltodextrin (MD-21DE), gum Arabic (GA), gum Arabic-modified starch (GA-MS), modified starch-chitosan (MS-CH) and modified starch-maltodextrin-chitosan (MS-MD-CH) were used as agents for beetroot and saffron coloring-extracts microencapsulation by freeze drying. The produced powders were evaluated in terms of coloring strength (E) during storage at 40°C for 10 weeks and a first-order kinetic was applied. Color parameters (L(*), a(*), b(*), C(*) and ΔE(*)) and water sorption behavior was also studied. Moreover, incorporation of the powders in a chewing gum model system was conducted. The type of encapsulating agent significantly (P<0.05) affected the studied parameters with the order of protection in both extracts being as follows: MD>GA>GA-MS>MS-CH>MS-MD-CH. The water sorption study revealed that MD and GA kept their structural integrity up to water activities of 0.66 and 0.82, respectively. The chewing gum samples produced with coloring extracts encapsulated in GA-MS showed the greatest a(*)(for beetroot) and b(*) (for saffron) values indicating a better protection.

Thermooxidative stability of fennel oleoresin microencapsulated in blended biopolymer agents.

UNLABELLED: In this work, the oxidative and thermal stabilities of 4 different encapsulating agents (chitosan [CH], modified starch [MS], gum arabic [GA], and maltodextrin [MD]) used in fennel oleoresin microencapsulation by the freeze-drying technique were evaluated both individually and in blends (binary and ternary ones). The oxidative stability of the encapsulated products was assessed by gas chromatography/mass spectrometry analysis of the secondary oxidation volatiles along with the use of oxidation markers (peroxide value, PV), while a differential scanning calorimetery analysis was conducted. Gum arabic, both plain and its mixtures, exhibited the lowest protection against lipid oxidation, presenting high PVs. However, good microencapsulation efficiency along with the best oxidative stability in terms of PV and thermal stability indicated that the formulations of MS-CH and MS-MD-CH could be suggested as alternative encapsulating agents. PRACTICAL APPLICATION: Herbal oleoresins including fennel can provide various nutritional benefits; however, they are sensitive to oxidation and should be microencapsulated. Therefore, there is a need for encapsulating agents that provide good microencapsulation efficiency and enhance at the same time oxidative and thermal stability.

Staling of cereal bran enriched cakes and the effect of an endoxylanase enzyme on the physicochemical and sensorial characteristics.

UNLABELLED: The staling of cakes enriched with untreated brans and endoxylanase-treated brans was evaluated by monitoring the changes in physicochemical, thermal, and sensorial properties of cakes during 7-d storage. Oat and rice bran were treated with different levels (0, 70, and 700 ppm) of an endoxylanase enzyme and added to cakes on 30% flour weight basis. Moisture losses, water activity, crumb firmness, starch retrogradation, and sensorial characteristics were used as staling indicators. Avrami-type equations were efficiently used for modeling the starch retrogradation kinetics, while linear models most adequately described crumb firming kinetics. Cake staling induced an increase in crumb firmness and enthalpy of amylopectin retrogradation, and a decrease in crumb moisture and sensory quality and acceptability scores of cakes. Oat bran-containing cakes better maintained their characteristics compared to the ones containing rice bran along the 7-d storage. Endoxylanase treatment of brans delayed the changes naturally induced during staling in crumb moisture content, amylopectin retrogradation enthalpy, and crumb firmness in the respective cakes. Deterioration of the sensorial characteristics was slower for the cakes containing endoxylanase-treated brans, as well. The level of endoxylanase treatment did not differentiate significantly (P < 0.05) any of the staling indicators. Overall, this study demonstrated that addition of endoxylanase-treated brans can result in cakes with improved nutritional characteristics and increased shelf life. PRACTICAL APPLICATION: The results of the study show the potential of using enzymes to modify underutilized food sources that can be properly incorporated in baked goods, improving their nutritional value, their quality characteristics, and providing longer shelf life. The developed procedure and results can be utilized by the bakery industry to make high fiber and low cost bakery products with improved sensorial characteristics that are appealing to the consumers.

Development of fibre-enriched gluten-free bread: a response surface methodology study.

The enrichment of gluten-free (GF) baked products with dietary fibre (DF) seems to be necessary since it has been reported that coeliac patients have generally a low intake of DF due to their GF diet. Response surface methodology was used to optimize a fibre-enriched GF bread formulation based on corn starch, rice flour and hydroxypropylmethyl cellulose. Maize fibre and water were the predictor variables (factors), and loaf specific volume, crumb firmness and crumb L value were the dependent variables (responses) used to assess the product quality. The optimal formulation, determined from the data, contained 6.5% maize fibre and 102.5% water, starch/flour base. The developed mathematical models for the measured responses could be successfully used for their prediction during baking. Shelf-life study of the optimized formulation revealed that bread stored under modified atmosphere packaging exhibited lower crumb firmness and moisture content values, and thus remained softer through storage. Scanning electron microscopy of the crumb showed a continuum matrix between starch and maize fibre, in the optimized formulation, obtaining a more aerated structure.

Kinetics of maneb degradation during thermal treatment of tomatoes.

The kinetics of maneb degradation in tomato homogenates at high temperatures and at two pH values (4 and 9) and the rate of formation of the toxic metabolite, ethylenethiourea (ETU), were studied. Maneb was measured as carbon disulfide by headspace gas-chromatography and ETU by high-performance liquid chromatography with photodiode array detection. First-order kinetics adequately described the degradation of maneb in tomato homogenates. The degradation rate constants exhibited an Arrhenius temperature dependence in the range from 50 to 90 degrees C and the apparent activation energy (E(a)) was calculated to be 36 KJ mol(-1) in homogenates with natural pH (4). Raising temperature from 60 to 75 and to 90 degrees C, ETU formation was significantly increased. Interestingly, the selectivity toward ETU showed a downward trend when the total conversion increased at longer heating times. When the pH of the tomato homogenates was adjusted to 9, the degradation of maneb proceeded faster at both 60 and 90 degrees C. The combination of alkaline pH and the highest temperature (90 degrees C) resulted in the maximum ETU conversion rates. The results of the present study on the fate of maneb and ETU residues during tomato processing, may prove valuable in estimating potential risk from dietary exposure.