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This study aims to produce a new type of healthy functional kefir by adding olive (Olea europaea) leaf extract and to determine its potential effect on the quality (physicochemical, sensory, phenolic contents and antioxidant properties) of kefir samples during storage at 4°C for 21 days.

For this purpose, four kefir samples were produced by using olive leaf extract in different amounts (A: 0% (control), B: 0.1%, C: 0.15% and D: 0.35%). The physicochemical, sensory, phenolic contents and antioxidant properties of kefir samples were investigated during Days 1, 7, 14 and 21 of storage. The study was conducted to optimize the olive leaf extract addition level to obtain better-quality kefir functional food.

From the results, it was determined that the addition of olive leaf extract affected the entire chemical components of the kefir samples (p < 0.05). It was found that the pH value decreased during storage. By contrast, it was observed that titration acidity values increased. The kefir sample with 0.35% olive leaf extract (D) had the highest total phenolic and antioxidant activity content (1,292.75 mg GAE/L and 10.20 mM TE, respectively) among the samples (p < 0.05). In the sensory analyses, the kefir sample with the highest score – in terms of sensory attributes – was the kefir sample containing 0.15% olive leaf extract (C).

Thus, it was concluded that kefir with added olive leaf extract could serve as a functional kefir of benefit to human health. When we looked at the enrichment studies on kefir as a functional product, no study has been found on the use of olive (Olea europaea) leaf extract, especially with kefir. In this sense, it is thought that the study will contribute to published literature.

The purpose of this paper is to evaluate the market potential of food obtained from olive by-products. The marketing of such by-products (e.g. olive leaves and pulp) is a challenging opportunity for the sustainable development of the sector. Yet, consumer demand is still poorly understood. The paper contributes to filling the knowledge gap with an empirical survey of a sample of Italian consumers.

The authors provide an assessment of consumers’ willingness to accept (WTA) food from olive by-products. The authors collected structured questionnaire from a sample of 289 Italian consumers. The authors asked to consumers their willingness to try a variety of food products containing olive by-products, as a proxy for their WTA the products. In order to investigate the drivers of the average WTA, the authors used the information in the questionnaire to build four constructs of interest: technophobia, neophobia, perception of benefits and awareness about sustainable consumption. The choice of the constructs and the variables was driven by the existing literature.

The paper shows how the WTA food with olive by-products is a general attitude of the consumer, rather than product-specific choice. The results suggest that consumers perceive the use of olive by-products as a new technology for preparing well-known food products. The authors did not find statistical evidence of the wariness of olive by-products as new food products. Technophobia is the most important factor hampering the marketing of olive by-products.

The paper is a first attempt of exploring the topic of WTA food with olive by-products.

This paper aims to evaluate hematological parameters, blood glutathione (GSH), serum glucose-6-phosphate dehydrogenase (G6-PD) and liver function in favism animals' models after oral intake with a mixture of pickled olives and Vicia faba (V. faba) seeds.

Favism is a life-threatening hemolytic crisis. It results from the ingestion of V. faba by the individuals. The hemoglobin (Hb), hematocrit (Hct), red blood cells (RBCs), white blood cells (WBCs), serum glucose, blood GSH, serum G6-PD, serum thiobarbaturic acid reactive substances (TBARS), liver protein and liver function were evaluated after oral administration with a mixture of pickled olives with V. faba seeds in favism animals' models.

The favism-, vicine- and convicine-treated animals showed a significant decrease (p < 0.01) in Hb (6.42, 7.23 and 5.96 g/dl), Hct (25.4, 26.4 and 25.1%), RBCs (2.56, 2.45 and 2.60 106 cells/mm³, WBCs (4.35, 4.25 and 4.30 103 cells/mm³), serum glucose (95.8, 97.1 and 96.5 mg/dl), blood GSH (24.7, 26.6 and 23.8 mg/dl), serum G6-PD (15.8, 15.9 and 15.7 U/L), serum aspartate aminotransferase (6.35, 6.59 and 5.97 U/L), alanine aminotransferase (4.49, 4.61 and 4.50 U/L), total protein (6.54, 6.59 and 6.40 g/dl), albumin (3.84, 3.91 and 3.75 g/dl), globulin (2.70, 2.48 and 2.65 g/dl) and liver protein (3.37, 3.10 and 3.42 g/g tissue) but a significant increase (p < 0.01) in serum TBARS (38.7, 38.9 and 39.4 nmol/dl), alkaline phosphatase (275, 271 and 281 U/L) and total bilirubin (0.93, 0.89 and 0.91 mg/dl) compared to Hb (16.3 g/dl), Hct (45.3%), RBCs (5.80 106 cells/mm³), WBCs (9.45 103 cells/mm³), serum glucose (96.5 mg/dl), blood GSH (39.7 mg/dl), serum G6-PD (36.1 U/L), serum TBARS (18.0 nmol/dl), serum aspartate aminotransferase (19.8 U/L), alanine aminotransferase (9.23 U/L), alkaline phosphatase (214 U/L), total bilirubin (0.57 mg/dl), total protein (8.76 g/dl), albumin (4.85 g/dl), globulin (3.91 g/dl) and liver protein (6.28 g/g tissue) in control group. The oral administration with pickled olives + V. faba, pickled olives + vicine and pickled olives + convicine into favism animals' models, vicine-treated animals and convicine-treated animals, respectively pushed all the above-mentioned parameters to near the control levels.

V. faba contains vicine and convicine glycosides. Vicine and convicine glycosides in V. faba are hydrolyzed by intestinal microflora to aglycones divicine and isouramil, respectively. Divicine and isouramil are highly reactive compounds generating free radicals where divicine and isouramil are the main factors of favism. The ß-glucosidase in pickled olives converts both vicine and convicine glycosides into aglycones divicine and isouramil, respectively, in aerobic condition outside the human body (in inactive forms) and prevent these glycosides to cause favism.

The purpose of this paper was to explore the possibility of utilization of Ocimum sanctum Linn (Tulsi) leaf extract as a natural preservative in muscle foods. The products incorporated with Ocimum sanctum leaf extract were assessed for various oxidative stability and storage quality parameters.

The Ocimum sanctum leaf extract was incorporated at 300 mg/kg level in the formulation. Chicken sausages incorporated with Ocimum sanctum leaf extract along with control samples were aerobically packaged in low-density polyethylene pouches and assessed for lipid oxidation, physicochemical, microbiological and sensory characteristics under refrigerated (4 ± 1°C) conditions.

Ocimum sanctum leaf extract showed a significant (p < 0.05) effect on the lipid stability, as the treated products exhibited significantly (p < 0.05) lower thiobarbituric acid reactive substances (mg malonaldehyde/kg) and free fatty acid (% oleic acid) values in comparison to control. A significant (p < 0.05) effect was also observed on the microbiological characteristics of the products, as the treated products showed significantly (p < 0.05) lower values for total plate count, psychrophilic count and yeast and mould count. Significantly, (p < 0.05) higher scores were also observed for various sensory parameters of the treated products.

The paper has demonstrated the use of Ocimum sanctum leaf extract as a potential natural preservative, as it successfully improved the oxidative stability and storage quality of the products during refrigerated (4 ± 1°C) storage and may be commercially exploited as a natural preservative in muscle foods.

Particles are of the controlled release delivery systems. Also, topically applied olive oil has a protective effect against ultraviolet B (UVB) exposure. Due to its sensitivity to oxidation, various studies have investigated the production of olive oil particles. The purpose of this study was to use chitosan and sodium alginate as the vehicle polymers for olive oil.

The gelation method used to prepare the sodium alginate miliparticles containing olive oil and particles were coated with chitosan. Morphology and size, zeta potential, infrared spectrum of olive oil miliparticles, encapsulation efficiency and oil release profile were investigated. Among 12 primary fabricated formulations, formulations F₅ (olive oil loaded alginate miliparticles) and F₁₁ (olive oil loaded alginate miliparticles + chitosan coat) were selected for further evaluations.

The size of the miliparticles was in the range of 1,100–1,600 µm. Particles had a spherical appearance, and chitosan coat made a smoother surface according to the scanning electron microscopy. The zeta potential of miliparticles were −30 mV for F₅ and +2.7 mV for F₁₁. Fourier transform infrared analysis showed that there was no interaction between olive oil and other excipients. Encapsulation efficiency showed the highest value of 85% in 1:4 (olive oil:alginate solution) miliparticles in F₁₁. Release study indicated a maximum release of 68.22% for F₅ and 60.68% for F₁₁ in 24 h (p-value < 0.016). Therefore, coating with chitosan had a marked effect on slowing the release of olive oil. These results indicated that olive oil in various amounts can be successfully encapsulated into the sodium-alginate capsules cross-linked with glutaraldehyde.

To the best of the authors’ knowledge, no study has used chitosan and sodium alginate as the vehicle polymers for microencapsulation of olive oil.

The purpose of the present study was to evaluate the effect of green tea extract, fig and red pepper on the quality characteristics of chicken patties during refrigerated storage.

The study was designed to evaluate the effect of green tea extract, fig and red pepper on the storage quality parameters of chicken patties. The products were developed by incorporating optimum level of green tea extract (400 mg/kg), fig (4 per cent) and red pepper (10 per cent) separately and were aerobically packaged in low-density polyethylene pouches and assessed for various storage-quality parameters under refrigerated (4 ± 1°C) conditions for 21 days of storage. The products were evaluated for various physicochemical, microbiological and sensory parameters at regular intervals of 0, 7, 14 and 21 days.

A significant (p < 0.05) effect of green tea extract, fig and red pepper was observed on the pH and TBARS (mg malonaldehyde/kg) values of the chicken patties. A significant (p < 0.05) effect was also observed on the microbiological characteristics as the products incorporated with green tea extract, fig and red pepper showed significantly (p < 0.05) lower values for total plate count, psychrophillic count and yeast and mould count during the period of storage. Coliforms were not detected throughout the period of storage. Significantly (p < 0.05) higher scores were observed for various sensory parameters of the products incorporated with green tea extract, fig and red pepper.

Green tea extract (400 mg/kg), fig (4 per cent) and red pepper (10 per cent) successfully improved the oxidative stability and storage quality of the products during refrigerated (4 ± 1°C) storage and may be commercially exploited to improve the storage quality of muscle foods without adversely affecting the sensory quality of the products.

The purpose of this paper was to evaluate the effect of pomegranate seed powder, grape seed extract and tomato powder on the quality characteristics of chicken nuggets during refrigerated storage.

The study was designed to evaluate the effect of pomegranate seed powder, grape seed extract and tomato powder on the storage quality parameters of chicken nuggets. The products were developed by incorporating optimum level of pomegranate seed powder (3 per cent), grape seed extract (0.3 per cent) and tomato powder (2 per cent) separately and were aerobically packaged in low-density polyethylene pouches and assessed for various storage quality parameters under refrigerated (4±1°C) conditions for 21 days of storage. The products were evaluated for various physico-chemical, microbiological and sensory parameters at regular intervals of 0, 7, 14 and 21 days.

A significant (p < 0.05) effect of pomegranate seed powder, grape seed extract and tomato powder was observed on the pH and thiobarbituric acid reacting substances (mg malondialdehyde/kg) values of the chicken nuggets. A significant (p < 0.05) effect was also observed on the microbiological characteristics, as the products incorporated with pomegranate seed powder, grape seed extract and tomato powder showed significantly (p < 0.05) lower values for total plate count, psychrophilic count and yeast and mould count during the period of storage. Coliforms were not detected throughout the period of storage. Significantly (p < 0.05) higher scores were observed for various sensory parameters of the products incorporated with pomegranate seed powder (3 per cent), grape seed extract (0.3 per cent) and tomato powder (2 per cent).

Pomegranate seed powder (3 per cent), grape seed extract (0.3 per cent) and tomato powder (2 per cent) successfully improved the oxidative stability and storage quality of the products during refrigerated (4±1°C) storage and may be commercially exploited to improve the storage quality of muscle foods without adversely affecting the sensory quality of the products.

This paper aims to investigate influence of extraction solvent on the efficacy of apricot pomace extract (APE) as a sustainable corrosion inhibitor for mild steel in sodium chloride solution.

The chemical profiles of the extracts were analyzed using gas chromatography–mass spectrometry. Total phenolic, total flavonoid content and antioxidant properties of the extracts were determined. Besides, gravimetric, potentiodynamic polarization and atomic force microscopy were used to study the corrosion inhibition. The effect of immersion period on inhibition efficiency was evaluated. The reaction mechanism of the inhibitor was also discussed.

Corrosion inhibition decreasing is in the following order: solution of 2-propanol/ethanol apricot pomace (E/PAPE) extract > ethanol (EAPE) > 2-propanol (PAPE). The gravimetric, polarization measurements and surface analysis revealed that the growth of inhibitory properties is prolonged, and corrosion rate reduction after 40–48 h of exposure was studied.

APEs play an important role in the corrosion inhibition of mild steel in sodium chloride solution. Moreover, its application is potentially possible in industries.

The results contribute to the integrated valorization of food waste.

The different compositions of the conversion/oxidation products of organic substances in solution were studied. The formation of polymerized flavanol-aldehyde adducts and oxidized quinone compounds or tautomers structures because of extract transformation in water causes main corrosion reduction in 40–48 h.

The purpose of this study is to determine the effect of olive cake (OC) on lipid peroxidation as well as antioxidant enzymes activities of serum, red blood cells (RBCs) and liver, in streptozotocin (STZ)-induced-diabetic rat fed cholesterol-enriched diet.

Hypercholesterolemic male rats were rendered diabetic (HC-D) by a single intraperitoneal injection dose of STZ (35 mg/kg BW). HC-D rats were divided into two groups fed for 28d a diet supplemented with OC at 7.5 percent (HC-D-OC) or not (HC-D). A control group (C) was submitted to standard diet containing 20 per cent casein for the same experimental period.

RBCs, serum and liver thiobarbituric acid reactive substances (TBARS) contents were significantly increased in HC-D, compared to C group (p = 0.04, p = 0.02 and 0.03). These values were significantly decreased (48 per cent and 64 per cent; p = 0.02 and p = 0.0007) in serum and liver of HC-D-OC vs HC-D group. In RBCs, superoxide dismutase (SOD), catalase (CAT), and glutathione S-transferase (GST) activities were, respectively, 1.5, 2- and 1.7-fold higher (p = 0.03, p = 0.008 and p = 0.03) in HC-D group compared to HC group. In serum and liver, SOD, CAT and GST activities were, respectively, 1.3-, 2.6- and 1.6-fold increased (p = 0.03, p = 0.007 and p = 0.02). In HC-D-OC compared to HC-D group, RBCs glutathione peroxidase (GSH-Px), CAT and GST activities were, respectively, 2.1-, 3.3- and 2.1-fold higher (p = 0.04, p = 0.0009 and p = 0.03). In serum, SOD and CAT activities were, respectively, 1.5- and 1.9-fold increased (p = 0.02, p = 0.02). In liver, SOD, GSH-PX, CAT and GST activities were significantly increased (p = 0.005, p = 0.03, p = 0.02 and p = 0.04).

In diabetic rats-fed cholesterol-enriched diet, OC was able to reduce oxidative stress by decreasing lipid peroxidation and increasing antioxidant enzymes activities in serum, RBCs and liver.

The purpose of this study is to explore the possibility of utilization of lemon peel extract as a natural antioxidant source in muscle foods. The products incorporated with lemon peel extract were assessed for various oxidative stability and storage quality parameters.

The study was designed to evaluate the effect of lemon peel extract on the oxidative stability and storage quality of Tabak-Maz, a popular traditional meat product. The products were prepared and treated with different concentrations of lemon peel extract (0.5, 1, 1.5 per cent) and were aerobically packaged in low-density polyethylene pouches and assessed for lipid stability and storage quality parameters under refrigerated (4 ± 1°C) conditions.

Lemon peel extract showed a significant (p < 0.05) effect on the lipid stability of the products as the treated products exhibited significantly (p < 0.05) lower thiobarbituric acid-reactive substances (TBARS) (mg malonaldehyde/kg) and free fatty acid (FFA) (per cent oleic acid) values for the entire period of storage. A significant (p < 0.05) effect was also observed on the microbiological characteristics of the products, as lemon peel extract treated products showed significantly (p < 0.05) lower values for total plate count, psychrophillic count and yeast and mould count throughout the period of storage. Coliforms were not detected throughout the period of storage. Significantly (p < 0.05) higher scores were observed for various sensory parameters of the treated products.

Lemon peel extract successfully improved the oxidative stability and storage quality of Tabak-Maz during refrigerated (4 ± 10°C) storage and may be commercially exploited as a natural antioxidant source in muscle foods.