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Acta Alimentaria
Authors: J. Radović, A. Leković, A. Damjanović, Đ. Kopanja, M. Dodevska, T. Stanojković, T. Marinković, Č. Jelić, and T. Kundaković-Vasović

Abstract

The composition of biologically active compounds of Calocybe gambosa (Lyophyllaceae) was analysed, and the antioxidant and cytotoxic activities were tested in vitro. C. gambosa was low in energy, fat, and carbohydrates, but rich in proteins and fibres. The total polyphenol content in the extracts was low (23.08 ± 0.67 in aqueous and 24.99 ± 4.25 μg GA mg−1 of extract in methanolic extract). The methanolic extract showed anti-DPPH radical activity with an IC50 of 626.10 ± 25.20 μg mL−1. The sample of C. gambosa is rich in nucleotides and amino acids responsible for its pleasant taste. The nucleoside and 5′-monophosphates contents were 0.97 mg g−1 and 2.32 mg g−1 of dry mushroom, respectively. The contents of essential and non-essential amino acids were 18.41 ± 0.06 and 41.75 ± 0.30 mg g−1 d.w., respectively. The percentages of saturated and unsaturated fatty acids were 42.6% and 57.4%, respectively. The most abundant water-soluble and fat-soluble vitamins were B1 and E, respectively. Cytotoxic effect of the extracts was examined against different cancer cell lines, and the best cytotoxicity was showed by the peptide extract against colon cancer cell line LS174.

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Abstract

Pre-drying prior to freezing may reduce several freezing drawbacks. Nevertheless, drying may cause nutritional quality losses. Instant Controlled Pressure Drop process has been proposed to intensify pre-drying process. This research is dedicated to study the evolution of the main bioactive compounds (total phenolics, flavonoid, and tannins contents) of quince dehydrofrozen fruits. Fresh samples were subjected to air drying at 40 °C and 3 m s−1 air velocity down to a final water content of 0.3 g g−1 db. Pre-dried samples were Instant Controlled Pressure Drop (DIC) treated under different conditions, i.e. saturated steam pressure (P) and treatment time (t), following a 2-factor/5-level Experimental Design. Treated fruits were frozen at –30 °C then were thawed at 20 °C in order to study the impacts of DIC on phenolic compounds. Response Surface Methodology (RSM) confirmed that pressure was the most influencing parameter in terms of polyphenol, flavonoid, and tannins contents. Finally, DIC pre-treatment allowed the improvement of phenolic content retention compared to untreated DIC samples.

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Abstract

Quinoa is a pseudocereal having outstanding nutritional profile and health-promoting biofunctional compounds. It is able to pop into an affordable, crispy, and flavourful ready-to-eat snack by conventional oil-popping method. Oil-popping is the process of frying grains in hot oil for a short time to induce vapour-driven expansion of grains. The effects of process variables on oil-popping quality of quinoa were evaluated. The conditions of processing were optimised using Response Surface Methodology. The grains (10 g) were hydrated by adding 0.1–0.3 mL of water containing a varying salt concentration of 0–1%, w/w and popped in coconut oil maintained at a popping temperature of 200–240 °C for a popping time of 10–30 s. The developed popped quinoa was analysed for popping quality indices. It was found that the increase in popping temperature, popping time, and salt concentration, and decrease in moisture level significantly decreased bulk density but increased popping yield (% popped grains), expansion ratio (degree of volume expansion), and flake size (average kernel size) of popped quinoa. Overall acceptability of popped quinoa in terms of sensory attributes was positively correlated with popping temperature and popping time. The optimised variables generated a popping yield of 75.56%, expansion ratio of 3.07, flake size of 11.58 mm3, bulk density of 0.29 g mL−1, and overall acceptability score of 8.40. A threefold expansion and a fair popping yield obtained from oil-popped quinoa offer a significant potential to generate profit for manufacturers.

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Abstract

With the enhancement of people’s awareness of drinking health, the health factors in Wuliangye-flavour liquor is worth our attention. Bacterial communities in 4 layers of Zaopei from the same fermentation pit and amino acids as major health factors in 4 liquors directly related Zaopeis were investigated by Illumina MiSeq sequencing and liquid chromatography mass spectrometry, respectively. Results indicated that 18 amino acids were detected and 8 dominant bacteria (genus level) were observed. Meanwhile, total amino acids, 11 amino acids (Glu, Asp, Val, etc), bacterial diversity, and the percentages of Lactobacillus and Pseudomonas increased with the increase of Zaopei’s depth; 5 amino acids (Pro, Ser, Phe, etc) and the percentages of Pediococcus and Bacteroides first increased and then decreased with the increase of Zaopei’s depth. Moreover, 11 amino acids were significantly (P < 0.01) and strongly (|ρ| > 0.8) positively correlated with Lactobacillus and Pseudomonas numbers.

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Abstract

A number of methods have been applied to measure total antioxidant capacity (TAC), including FRAP, which is based on reducing the amount of iron ions in a complex compound. Researchers often use measurement of absorbance 10 min after mixing a sample with the FRAP reaction solution to calculate TAC. The FRAP solution has been shown to alter absorbance over time by ca 0.0010–0.0020 per hour, under storage conditions. This article intends to show that some substances do not fully or sufficiently react within the common analysis period. It is evident from the results that some substances react more quickly and others very slowly. Absorbance in relation to various phenols was measured. Compared to the levels of absorbance at 10 min, mean absorbance at 48 h was higher by 5,395% for vanillin, 426% for caffeic acid, 170% for sinapinic acid, 67% for gallic acid, 19% for syringic acid, and only by 4% for Trolox. Results for vanillin and caffeic acid indicate potential auto-catalysis.

Open access

Abstract

Hungarian fruit vinegars were characterised in terms of physicochemical attributes (total polyphenol content, antioxidant characteristics/FRAP, CUPRAC, ABTS/, ascorbic acid content, pH, total soluble solids), sensory profiles, and antimicrobial properties.

Both compositional and sensory profiles showed distinct patterns depending on the type of vinegar (Tokaj wine, balsamic or apple) and the additional fruit used. Balsamic vinegars maturated on rosehip, sea buckthorn, and raspberry showed outstanding antioxidant performances. Rosehip, raspberry, and quince vinegars, as well as vinegars produced from Tokaji aszú and balsamic apple obtained high scores for fruity and sweet notes.

Antimicrobial activities were tested on Gram-negative and Gram-positive organisms, including probiotic bacteria. Generally, only weak activities were obtained, which was attributed to the natural sugar content of the samples, depending on the type of the vinegar and the fruit. Similar results, but more pronounced bacterial growth inhibitions were obtained for probiotic strains, however, some probiotic strains were resistant to at least two of the vinegars. Based on these, balsamic apple, raspberry, rosehip, quince, and sea buckthorn may qualify as potential functional components of probiotic preparations containing some of the strains tested.

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Abstract

Marine organisms have attracted considerable attention in recent years. In this study, peptides with osteogenic activity from Pinctada martensii were isolated and identified. Additionally, the effects of the hydrolysates on MC3T3-E1 cell proliferation and differentiation were evaluated using the MTT and alkaline phosphatase (ALP) assays, respectively. First, trypsin, pancreatin, and neutral protease were used to hydrolyse the intact shellfish. The hydrolysates with the greatest effects on osteoblast proliferation and ALP activity were separated and purified. Second, fraction WP2 was isolated and purified using a Sephadex G-25 column. WP2, which had the highest osteogenic activity, increased cell growth by 48.57 ± 0.05% and ALP activity by 6.27 ± 0.07 mU. Finally, four novel peptides were identified in WP2 (FDNEGKGKLPEEY, IVLDSGDGVTH, IVLDSGDGVSH, and SSENSDLQRQ) by Orbitrap Fusion Lumos Tribrid orbital liquid chromatography-mass spectrometry. Our findings revealed that P. martensii contains peptides with potential osteogenic activity.

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Abstract

Aroma components of wines play an important role in the sensory quality of wines. In our paper we investigate the effect of commercially available yeast nutrients under different fermentation parameters. Caproic acid, caprylic acid, capric acid, and different fatty acid esters were used as markers of the alcoholic fermentation process. The optimal temperature for the fermentation of different white wines was at 15–16 °C, in the case of examined wines lower concentrations of fatty acids and fatty acid esters were found at this temperature. At 25–26 °C fermentation temperature very high concentrations of fatty acids and fatty acid esters were detected. Applying different nitrogen-containing wine additives we managed to achieve better aroma profiles for white wines even using musts of lower quality.

Open access

Abstract

Consumers increasingly address their attention to healthy fruits produced under organic agricultural managements. However, such produce may be less appealing in appearance influencing the purchase decisions of consumers. This research had the purpose to determine on three Italian local apple cultivars (Casciana, Rosa, Ruggine) the sensory appreciation of fruit through experiments conducted with blind (BC) and sighted (SC) consumers. The appreciation of apples differed between consumers with different visual ability. This aspect mainly concerned cvs Casciana and Rosa with contrasting fruit appearance traits. The BCs were inclined to better evaluate Casciana apples characterised by less attractive fruits. Conversely, the visual factor could have influenced the SCs’ judgment, as they appreciated Rosa more by the best outer traits of fruits. Intriguing responses were obtained when SCs were blindfolded.

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