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Volume 13, Issue 2, 2024
Online ISSN: 2182-1054
Volume 13 , Issue 2, (2024)
Published: 18.10.2024.
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Contents
18.04.2019.
Original scientific paper
Stability of vitamin C in broccoli at different storage conditions
In this study, the retention of vitamin C in fresh broccoli stored at different temperatures (i.e. chiller, room, cooking, and roasting or baking; 5-120oC) was investigated. The thermal stability of vitamin C in broccoli was analysed at 5, 20, 45, 60, 70, 80, 110, and 120oC. The vitamin C content was measured by the indophenol titration method. Vitamin C was affected negatively at all stored temperatures. The degradation of vitamin C was modelled by first-order reaction kinetics and the reaction rate constants were observed as 9.03Ö10−8 and 5.65Ö10−3 s −1 when stored at 5oC and 120oC, respectively. The activation energy was estimated as 74.2 kJ/mol within the temperature range used in this study. The lowest decay of vitamin C was observed during the chilling condition. The data on retention of vitamin C in broccoli could be used to determine their stability, when stored as raw, and when heated at different temperatures.
Nasser Al-Habsi, Sithara Suresh, Amani Al-Yhmedi, Marwa Al-Shoryani, Mostafa I. Waly, Mohammad Shafiur Rahman
18.04.2019.
Original scientific paper
Antioxidant indices and amino acid composition of phenolic containing Lima beans (Phaseolus lunatus) after simulated human gastrointestinal digestion
The present investigation was designed to characterize the phenolic profile of Lima beans (Phaseolus Lunatus) and also to evaluate the antioxidant indices: total phenolic content (TPC), total flavonoid content (TFC), ferric reducing antioxidant power (FRAP), 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity and amino acid composition at different stages of simulated gastrointestinal digestion (oral, gastric, intestinal). High Performance Liquid Chromatography (HPLC-DAD) analysis revealed the presence of some phenolic compounds (gallic acid, catechin, caffeic acid, rutin, quercitrin, quercetin, kaempferol and apigenin), with a reduced amount (mg/g) after cooking: gallic acid (raw: 1.96 ± 0.02; cooked: 1.82 ± 0.01); catechin (raw: 0.83 ± 0.01; cooked: 0.73 ± 0.01); rutin (raw: 2.61 ± 0.03; cooked:1.74 ± 0.03); quercitrin (raw: 5.73 ± 0.01; cooked: 5.68 ± 0.01); apigenin (raw: 2.09 ± 0.01; cooked: 1.79 ± 0.02), with exception of quercetin (raw: 2.11 ± 0.02; cooked: 5.73 ± 0.02) and caffeic acid (raw: 2.08±0.04; cooked 2.95 ± 0.04). The results of the antioxidant indices of in vitro enzyme digested lima beans revealed higher values for cooked Lima beans compared to the raw counterpart, with a stepwise increase at the different stages of in vitro digestion, with the exception of ferric reducing antioxidant power; TPC (oral digestion: 65.44 ± 0.96; gastric digestion:134.87 ± 0.46; intestinal digestion: 517.72 ± 4.70; mg/g tannic acid equivalent), TFC (oral digestion: 199.30 ± 6.43; gastric digestion: 1065.97± 1.22; intestinal digestion: 3691.87 ± 4.2; mg/g quercetin equivalent), DPPH (oral digestion: 85800.00 ± 305.50; gastric digestion: 99066.66 ± 115.47; intestinal digestion: 211354.20 ± 360.84; µmol TE/g sample). The results also revealed a progressive increase in the antioxidant indices and amino acid composition (mg/kg) for both raw and processed lima beans at various stages of the in vitro digestion, with the intestinal phase of simulated digestion ranking higher. This implied that the Lima beans contained some essential amino acids and antioxidant molecules that would be readily available after passing through the gastrointestinal tract and could therefore be explored as functional food in the management of free radical mediated diseases.
Sule O. Salawu, Oluwaseun M. Folorunso, Akintunde A. Akindahunsi, Aline A. Boligon
18.04.2019.
Original scientific paper
Moisture sorption isotherm and thermodynamic properties of jamun (Syzygium cumini L.) powder made from jamun pulp and seed
The present work aimed to: i) find the suitable proportion, based on sensory evaluation, of microwave-convective hot air dried jamun (Syzygium cumini L.) pulp and seed kernel powder to be mixed for the preparation of jamun powder (JP); ii) generate and model the moisture sorption isotherm (MSI) of JP; and iii) estimate net isosteric heat of sorption (qst), spreading pressure (Φ), net integral enthalpy (Qin), and net integral entropy (Sin). To formulate JP, the proportion (w/w, db) comprising 2% kernel and 98% pulp powder was the most desirable. The Peleg model was the best fit to MSI of JP. The qst decreased following linear relationship from 11.02 kJ. mol−1 at 5% equilibrium moisture content (EMC) to 0.27 kJ. mol−1 at 30% EMC. The Φ increased with increase in water activity and decreased with increase in temperature from 25 oC to 35 oC, and the values of Φ at 45 oC were even higher than at 25 oC. Net integral enthalpy (Qin) initially decreased till 6% moisture content in JP and displayed an increasing trend with further increase in moisture content. On the contrary, Sin kept on decreasing continually with increasing moisture content. The moisture zone of 7-11% was considered safe for storage of JP within the temperature range of 45-25 oC.
Indira Dey Paul, Madhusweta Das
18.04.2019.
Original scientific paper
The impact of processing methods on chemical composition, mineral bioavailability and functional properties of Nigerian-grown cashew flour
In this study, the effect of processing methods on the nutritional quality and functional properties of cashew (Anacardium occidentale Linn) kernels were investigated. The kernels were soaked, autoclaved, roasted or germinated at varying time duration; raw kernel served as control. The samples were analysed for chemical, mineral bioavailability and functional properties. Data was subjected to analysis of variance and means were separated by the Duncan multiple range test. The result of chemical composition analyses revealed that raw cashew kernels contained 3.55±0.08% moisture, 21.3±0.05% protein, 45.0±0.15% fat, 2.53±0.02% fibre, 1.59±0.02% ash, 26.1±0.01% carbohydrate, 521.75 Kcal/g energy, 2210.09±0.02mg/kg calcium, 1712.54±0.03mg/kg magnesium, 60.04±0.01 mg/kg iron and 36.74±0.02mg/kg zinc. Tannin, phytate and oxalate concentrations in the raw cashew kernel were 10.14±0.03 mg/kg, 99.30±0.02mg/kg and 11.03±0.03mg/kg respectively. Increased fat, ash and fibre levels were noted for treated samples compared to raw kernels. Mineral concentrations were increased significantly by various treatments compared to raw kernel; however, germination resulted in the highest increase of mineral content. A reduction trend was observed in phytate, oxalate and tannin concentrations in the treated samples with respect to increased processing time. Consequently, various treatments influenced the bioavailability of mineral elements. Treated samples exhibited significant differences in loose and packed bulk densities, water and oil absorption capacities when compared to raw kernels. Germination shows potential to generate not only much needed nutrients in cashew for human development, but also improved bioavailability of nutrients and functionality compared to other processing methods. This approach can used in Community Nutrition and Emergency Feeding Programmes, in developing countries, where the consequence of anti-nutritional factors may worsen the incidence of malnutrition and disease.
Folasade Makinde, Joel Ifeoluwa Hannah
18.10.2018.
Original scientific paper
Extraction kinetics of saponins from quinoa seed (Chenopodium quinoa Willd)
Quinoa has higher protein content (11-16% m/m) and better amino acid profile than cereals and represents a valuable resource for healthy nutrition. The aim of this work was to study the saponins extraction kinetics during washing of soaked quinoa. The experimental curves of saponins content as a function of time was measured at water temperatures of 20, 40, 60, and 70ºC. A spectrophotometric method was proposed to determine total saponins content, while an unsteady state diffusional model was applied to this extraction problem, assuming strict internal control to the mass transfer rate. As a first analysis, the complete analytical solution for constant diffusion coefficient (Deff) using the initial radius (R0) provided an accurate predicted curve at each temperature. The diffusion coefficients (around 10−10 m2s-1), were correlated with temperature using an Arrhenius-type relationship to obtain an activation energy Ea of 16.9 kJ mol-1. The preliminary values of Ea and preexponential factor (D0) thus obtained were used as initial values of a second, more robust fitting where the whole dataset of saponins concentrations as a function of time for all temperatures. The Arrhenius equation was directly inserted into the diffusional solution. The following parameters were obtained: Ea= 17.2 kJ mol-1 and, D0= 3.232×107 m2 s-1, respectively with an overall r2=0.985. Saponins content agreed well with experimental values. As the equation is capable of predicting saponin extraction times for various operating conditions, it can be used within equipment design schemes.
R. M. Torrez Irigoyen, Sergio Giner
18.10.2018.
Original scientific paper
Antioxidant and antibacterial activities of exopolysaccharides produced by lactic acid bacteria isolated from yogurt
The objectives of this study were to optimize the conditions for cell growth and exopolysaccharides (EPS) production by using pure and mixed microbial cultures of Streptococcus thermophilus and Lactobacillus bulgaricus, and to evaluate the antioxidant and antibacterial activities of EPS in vitro. The mixed cultures of two strains showed a higher cell growth whereas the higher EPS production was detected in pure culture with S. thermophilus. The optimal medium were determined as follows (g/l): sucrose 50, yeast extract 10, KH2PO4 3 , MgSO4.7H2O 0.05 and pH initial 6.5 at 30°C. Under the optimized conditions, the values of dry cell weight (DCW) and EPS were 5.2± 0.8 g/l and 56.8 ± 0.62 mg/ml, respectively. The EPS demonstrated a positive antioxidant potential on DDPH radical scavenging. The agar diffusion assay showed that purified EPS exhibited antibacterial activities against tested pathogens such as Escherichia coli ATCC 250922 and Staphyloccocus aureus ATCC 250923 at (62-1000) μg/mL. In conclusion, EPS have an antioxidant activity and could have applications in the food industry.
Benattouche Zouaoui, Djillali Bouhadi, Ghalem Bachir Raho
18.04.2018.
Original scientific paper
Food oral processing in humans: links between physiological parameters, release of flavour stimuli and flavour perception of food
In humans, food oral processing (FOP) is the first step in the digestive process. It prepares the food for swallowing and to undergo the process of digestion. During chewing, the food is comminuted by the combined action of chewing and saliva to form a bolus. The particle size of the bolus is reduced due to the action of the tongue and the teeth, and the saliva is continuously produced by the salivary glands to humidify and impregnate the food. Saliva lubricates the bolus and enables the cohesion of particles to prepare for swallowing. During food oral processing, the compounds responsible for food flavour and taste are released, leading to the perception of food organoleptic properties and significantly contributing to the consumer’s acceptability of the product. Understanding this process of food breakdown and bolus formation thus appears to be a way to revisit food functional properties. However, this process is extremely complex, and as such, its description necessitates a combination of many quantities from different disciplines, i.e., physics, chemistry, physiology, psychology, behavioural science and food science. It depends, on one hand, on food properties and on the other hand, it depends on oral physiology. However, large inter-individual variability is commonly observed, which has important consequences on flavour release and perception. The challenge for the food industry is to be able to develop food considering this large variability, and sensory and nutritional constraints. This challenge is particularly relevant when specific populations (i.e., elderly, infants or obese subjects) are considered.
Gilles FERON, Christian Salles
18.04.2018.
Original scientific paper
Examination of optimum test conditions for a 3-point bending and cutting test to evaluate sound emission of wafer during deformation
The purpose of this study was to investigate optimum test conditions of acoustical-mechanical measurement of wafer analysed by Acoustic Envelope Detector attached to the Texture Analyser. Forcedisplacement and acoustic signals were simultaneously recorded applying two different methods (3-point bending and cutting test). In order to study acoustical-mechanical behaviour of wafers, the parameters “maximum sound pressure”, “total count peaks” and “mean sound value” were used and optimal test conditions of microphone position and test speed were examined. With a microphone position of 45° angle and 1 cm distance and at a low test speed of 0.5 mm/s wafers of different quality could be distinguished best. The angle of microphone did not have significant effect on acoustic results and the nu
ERDEM CARSANBA, Gerhard Schleining
18.04.2018.
Original scientific paper
Fermentation of tender coconut water by probiotic bacteria Bacillus coagulans
Coconut water is currently being considered as an elixir for patients suffering from diseases like dengue and malaria as well as chikungunia to provide hydration properties to the body. It has become a popular beverage for many people owing to its palatability and high mineral content. In this study, the growth, survival and fermentation performance of the probiotic bacterium Bacillus coagulans in coconut water was assessed in order to produce a novel non-dairy, probiotic beverage. The species was characterized on the basis of morphology, physiology and biochemical parameters and its probiotic attributes were assessed. Batch fermentations were carried out for 2 days at a constant 37°C, thereafter the samples were subjected to microbiological and chemical analysis. The results suggested that the specie produced lactic acid and was acid and bile tolerant. The pH and titratable acidity of probiotic fermented coconut water were found to be 4.4 and 0.53 % lactic acid, respectively. The viscosity of fermented coconut water increased significantly from an initial 5.13 mPa.s to 5.35 mPa.s because of the increase in soluble solids content due to exopolysaccharide production by B. coagulans during fermentation. Also, the overall acceptability score of probiotic coconut water was higher than tender coconut water, suggesting its feasibility for use as a probiotic beverage.
Aishwarya Singh Gangwar, Aastha Bhardwaj, Vasudha Sharma