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Abstract

Effect of coating with calcium nitrate in three concentrations (0.0, 0.5, and 1.0 wt%) on chemical and mechanical properties, and impact behaviour of two apple cultivars (Golden Delicious (GD) and Red Delicious (RD)) during time (0, 2, and 4 months) was studied. Moisture content, pH, titratable acidity, °Brix, organoleptic properties, modulus of elasticity (E), yield stress, yield strain, and toughness were measured. The effect of impact loads was determined by measuring bruise volume (BV) and bruise susceptibility (BS). The results showed that pH and °Brix significantly increased, while titratable acidity, E, yield strain, toughness, and BV decreased during storage time. As Ca(NO3)2 concentration increased, titratable acidity, E, yield strain and yield stress increased and pH decreased (P < 0.05). Highest and lowest values for °Brix were observed in GD treated with 1.0% Ca(NO3)2 after four months (13.31) and GD treated with 0.5% Ca(NO3)2 at the first day (10.65), respectively. Maximum E was obtained in GD treated with 1.0% Ca(NO3)2 on the first day (2130 kPa) and this sample also showed the lowest BS after four months of storage (2.82 mL J−1), while the uncoated GD had the highest BS on the first day (7.11 mL J−1).

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Abstract

Bovine blood samples were treated with high hydrostatic pressure (HHP) to examine the changes that may occur in the blood related to its colour, microbiological characteristics, protein denaturation, and dynamic viscosity. Pressure treatments were carried out from 100 to 600 MPa in 100 MPa scale up, with 5 min holding time. The blood samples were treated with anticoagulant (EDTA) to eliminate the possible measurement distorting effects. We found that 2 log reduction in the microbial load could be achieved with a pressure treatment above 400 MPa. According to the protein denaturation measurements (DSC), blood proteins were resistant to pressure treatment, even at 300–400 MPa a substantial part of proteins remained in native state. The colour of the samples got darker with the rising pressure, however, visible colour change was observed only above 400 MPa. It can be established, that the HHP treatment was suitable to increase the microbiological stability of blood, without significantly changing its techno-functional properties.

Open access

Abstract

The main purpose of this study was to determine the chemical composition of monofloral bee-collected pollen from the coffee (Coffea robusta) plant and its pellet morphology. According to the results coffee bee pollen (CBP) has a high nutritional value. It contains a large percentage of protein, reducing sugar, and lipid. Also, vitamins (B2 and E) and minerals (K, Ca, and P) were found in CBP. In addition, the results revealed that the total polyphenols content (TPC) was 10.62 mg GAE/g dry weight (DW) and antioxidant activity (AA) of CBP was 5.52 μmol TE/g DW. Some physical properties of CBP pellet were recorded such as moisture, relative diameter, sphericity, bulk density, and colour parameters. The pollen pellet exhibits shapes of colour from light to dark yellow. These results pointed out that CBP can be used as a remarkable source of compounds with antioxidant activity and health-protective capacity for humans.

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Abstract

Green tea or its concentrated extract is coveted for its health promoting catechin-like polyphenols, especially epigallocatechin-3-gallate (EGCG). However, its amicable efficacy is now being doubted considering the recent occurrence of several cases of hepato- and nephrotoxicity, after the ingestion of EGCG-fortified (≥85–90%) nutritional supplements. Therefore, the current study was carried out to ascertain the effect of green tea leaves extract (GTE), having low EGCG content (73.8%), on liver and kidney functions of male Wistar rats using various in vivo experiments and in vitro radical scavenging activity. In terms of acute toxicity, GTE was observed to be safe when delivered at a dosage of 2000 mg kg−1 body weight (BW). Oral delivery of GTE for 28 days at a concentration of 200 mg kg−1 BW/day did not trigger sub-acute toxicity to the liver and kidneys, as per serum biochemical analyses and histopathological examination. In contrast, GTE counteracted the effects of carbon tetrachloride (a potent hepato-degenerative compound) on the liver. Furthermore, increase in high-density lipoprotein―cholesterol with concomitant lowering of serum triglycerides and low-density lipoprotein―cholesterol were noticed in GTE-treated rats. These findings suggest that low EGCG containing GTE, with appreciable antioxidant activity (IC50 = 53.18–71.28 μg mL−1), can serve as a hepatoprotective, hypolipidemic, and hypocholesterolemic ingredient.

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Abstract

Cake is a popular bakery product consumed by almost everyone due to its low economic cost and shelflife, however, it is recognised unhealthy because of high fat and sugar contents. The aim of this study was to evaluate physicochemical and sensory properties of muffins baked using 100% of sugar and fat replacement as stevia sweetener (rebaudioside A and erythritol) and chia seed mucilage, respectively. The combination of sweetener with chia gel (SCC) had the highest moisture content, while the replacement of fat in muffin (CC) revealed similarity to the control in lightness and redness values. There was also no significant difference in terms of firmness when only the sweetener was replaced (SC). While the control muffin obtained the highest overall acceptability score, the lowest score was observed in CC. Thus, muffins with reduced fat and sugar contents can benefit the consumer in terms of health, but further optimisation of formulations for both replacers is needed for better sensory acceptance.

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Abstract

Seventeen samples of Calabrian ewe’s milk, ewe’s cheese (Pecorino del Poro) made with raw milk, goat’s milk, and goat’s cheese (Caprino d’Aspromonte) made with raw milk were used to obtain 124 yeast isolates. The most abundant species was Debaryomyces hansenii (61.3%), followed by Candida zeylanoides (32.3%) and Kluyveromyces marxianus (3.2%). The enzymatic profile of 25 selected yeast strains was determined. Lastly, they were studied for their interaction with eight dairy lactic acid bacteria – four coccal-shaped and four rod-shaped. The best strains may be used as adjunct cultures for cheese making.

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Abstract

Ball and Beam system is one of the most popular and important laboratory models for teaching control systems. This paper proposes a new control strategy to the position control for the ball and beam system. Firstly, a nonlinear controller is proposed based on the backstepping approach. Secondly, in order to adapt online the dynamic control law, adaptive laws are developed to estimate the uncertain parameters. The stability of the proposed adaptive backstepping controller is proved based on the Lyapunov theorem. Simulated results are presented to illustrate the performance of the proposed approach.

Open access
Acta Alimentaria
Authors: H. Soltanmoradi, M.S. Maniati, A. Davoodabadi, A. Mosapour, S. Samavarchi Tehrani, M. Pazhoohan, F. Daemi, and H. Khaleghzadeh-Ahangar

Abstract

Depression is a common psychiatric disorder that can be continuous or recurrent. It has been previously reported that intestine probiotics play an essential role in the bidirectional communication of the intestine and brain. This study aims to investigate the antidepressant effects of kefir, a probiotic supplement, and Lactobacillus rhamnosus GG and their potentials in depression-like behaviour treatment in two-week and four-week treatments. In the present study, BALB/c mice were used for this purpose. The saline- and fluoxetine-treated groups were designed as negative and positive control groups, respectively. The forced swimming and tail suspension tests have been performed to assess the level of depression-like activity. We have observed that two-week treatment reduces the duration of depression-like activities, and four-week treatment enhances the antidepressant properties. Overall, our results suggest that kefir, L. rhamnosus GG, and the investigated probiotic supplement have antidepressant-like properties.

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Abstract

Cyclodextrins are widely used in various fields including food industry. In this review, their role in high carbohydrate-containing, starchy foods are reviewed and discussed. Both the effects as functional ingredients affecting the structural properties of starch and as active ingredients slowing down starch digestion and, as a consequence, decreasing the glycaemic index of starchy foods are overviewed without considering the traditional applications as carriers and stabilisers of aroma and flavour, essential oils, polyunsaturated fatty acids, and other bioactive components to enrich foods, even if they are carbohydrate foods. The effect on starch metabolism is explained by the structural transformations caused by cyclodextrins on starch amylose and amylopectin. Several examples are shown how the technological and sensorial properties of bread, rice products, pasta, and other starchy foods are modified by cyclodextrin supplementation, and how the digestibility is changed resulting in reduced glycaemic and insulinaemic effects.

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Abstract

Tomato (Solanum lycopersicum L.) is one of the important vegetables in the world due to large production area and consumer interest. Biotic and abiotic stresses have negative effect on tomato production. Utilisation of rootstocks conferring resistance to biotic stresses can be considered as the most effective and environment friendly solution in tomato production to overcome this problem. Although wild tomato species is a good rootstock candidate due to its resistance to multiple plant diseases, effects of wild tomato species as rootstock on mineral nutrient composition and fruit quality are not clear. In the present study, effects of interspecific hybrids derived from two wild tomato species (Solanum habrochaites and Solanum penellii) as rootstock on tomato fruit mineral nutrient composition (phosphor (P), potassium (K), calcium (Ca), magnesium (Mg), iron (Fe), zinc (Zn), manganese (Mn), and copper (Cu)) and fruit quality traits (soluble solids content (SSC), pH, percent titratable acidity (TA), and lycopene content) were evaluated. In the study, Amaron, Armstrong, and Arazi commercial rootstocks were used as control and AK0004 F1 (candidate tomato hybrid) was used as a source of scion. As result, only lycopene content was affected by different rootstocks. S. penellii was found to be with more potential for lycopene content. For mineral nutrient composition, all hybrids and controls had similar contents of potassium, phosphor, calcium, and magnesium. Manganese and copper contents decreased in all plants. S. habrochaites had more potential regarding nitrogen, iron, and zinc contens than S. penellii. This is the first study to evaluate two interspecific hybrids derived from S. habrochaites and S. penellii, and the results might be useful to understand effects of rootstocks derived from wild tomato species on mineral nutrient content and fruit quality.

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