Showing papers in "Lwt - Food Science and Technology in 2012"
TL;DR: In this paper, an antioxidant chitosan based edible films were developed incorporated with Zataria multiflora Boiss essential oil (ZEO) and grape seed extract (GSE) alone and in combination.
Abstract: Antioxidant chitosan based edible films were developed incorporated with Zataria multiflora Boiss essential oil (ZEO) (5 and 10 g/L) and grape seed extract (GSE) (10 g/L) alone and in combination. The physico-mechanical, wettability, swelling index, color, total phenol and antioxidant characteristics of the films were investigated. Films without any agents were used as control sample. All films, with the exception of 10 g/L GSE + 10 g/L ZEO film, exhibited lower strength and elongation values, and only the addition of 10 g/L ZEO to GSE film improved the water vapor transmission rate of chitosan films. Only GSE containing films had higher swelling index. The incorporation of GSE and ZEO into chitosan film increased the wettability of the surface, total phenol and antioxidant activity. Neat chitosan and ZEO incorporated films had a light yellowish color, whereas GSE + ZEO films were gray.
353 citations
TL;DR: In this article, two essential oils (EOs), thymol and carvacrol, with similar chemical structures were encapsulated in the nanoparticles of zein using the liquid-liquid dispersion method.
Abstract: Two essential oils (EOs), thymol and carvacrol, with similar chemical structures were encapsulated in the nanoparticles of zein using the liquid–liquid dispersion method. Three different pH treatments were applied to study the nanoparticles' morphology, structure, antioxidant property, and antimicrobial activity. The nanoparticles for all treatments were well dispersed in water. After lyophilizing, samples from the acidic condition tended to form film, but the samples from the neutral and basic conditions formed nanoparticles. The antioxidant properties were analyzed by 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) and Ferric ion spectrophotometric assay. DPPH was reduced in the range of 24.8–66.8% depending on the formulation and more than 65% hydroxyl free radicals were quenched by samples. An Escherichia coli reduction of 0.8–1.8 log CFU/ml was achieved in the presence of nanoparticles encapsulating EOs.
302 citations
TL;DR: In this paper, the tensile and barrier properties of biodegradable films (BF) based on cassava starch were analyzed and it was shown that the glycerol incorporation method did not influence the results (P < 0.05).
Abstract: In this study, glycerol content and its incorporation method on tensile and barrier properties of biodegradable films (BF) based on cassava starch were analyzed. ANOVA showed that the glycerol incorporation method did not influence the results (P > 0.05), however the glycerol content influenced significantly the tensile and barrier properties of the films (P 0.05).
260 citations
TL;DR: In this paper, the effect of adding buckwheat flour to wheat bread, particularly in higher dose, was evaluated by means of FRAP and DPPH, which increased by 2.36 fold and 3.64 fold respectively, in comparison with other pseudocereal flours (amaranth, quinoa), which caused, in higher doses, the changes of above parameters within the ranges 1.20e1.79 fold, and 0.60e 1.71 fold.
Abstract: The aim of the study was to investigate the effect of adding (in two different doses 15% and 30%) pseudocereal (buckwheat, amaranth and quinoa) flour on the antioxidant properties and sensory value of breads. Buckwheat flour had the highest phenolic content (7.25 � 0.23 mg/g dw). The content of total flavonoids in flours was about 2e4 fold higher when compared to breads. The addition of buckwheat flour to wheat bread, particularly in higher dose, was more effective in enhancing antioxidant activity, as evaluated by means of FRAP and DPPH, which increased by 2.36 fold, and 3.64 fold respectively, in comparison with other pseudocereal flours (amaranth, quinoa), which caused, in higher doses, the changes of above parameters within the ranges 1.20e1.79 fold, and 0.60e1.71 fold. Analysis of sensory results of breads showed that addition of buckwheat flour to the dough might improve subjective properties of bread and increase acceptable quality attributes such as taste, colour or odour. All these observations suggest that addition of buckwheat flour into bread can improve antioxidant as well as sensory properties of bread. Bread fortified with pseudocereal flours, and especially with buckwheat flour, may be placed on the market as a functional food.
253 citations
TL;DR: In this article, the physicochemical and functional properties of residual meals (M) and fibrous fractions (FRF) of chia seeds (Salvia hispanica L.), and to compare the effect of oil extraction methods (pressing -p- and solvent extraction -s-) and sieving process on these properties.
Abstract: The objective of this study was to characterize the physicochemical and functional properties of meals (M) and fibrous fractions (FRF) of chia seeds (Salvia hispanica L.), and to compare the effect of oil extraction methods (pressing -p- and solvent extraction -s-) and sieving process on these properties. Both processes affect the physicochemical and functional properties of residual meals and their corresponding fibrous fractions. Mp and FRFp showed a significantly higher residual oil content than Ms and FRFs (11.39, 10.85, 0.21 and 0.21 g/100 dry base, respectively). The sieving process of both meals allowed to obtain fibrous fractions with a significant increase of crude fiber (27.57, 32.84, 23.81 and 28.35 g/100 g in Ms, FRFs, Mp and FRFp, respectively), and a marked decrease of protein content (41.36, 35.32, 35.00 and 33.74 g/100 g in Ms, FRFs, Mp and FRFp, respectively). Total dietary fiber and their respective components (soluble and insoluble dietary fiber) were significantly higher in FRF. All the samples exhibited a high antioxidant activity due to the presence of phenolic compounds and tocopherols in the case of Mp and FRFp. Ms and FRFs presented a better oil-holding capacity, organic molecule absorption capacity, emulsifying activity and emulsion stability than Mp and FRFp, and allowed to achieve more stable emulsions. FRFs showed the highest values of water absorption and adsorption capacity.
250 citations
TL;DR: In this paper, the physicochemical, functional, antinutritional and pasting properties of taro, rice, pigeonpea flours and their blends were determined and related to each other using Pearson correlation and Principal Component Analysis (PCA).
Abstract: Physicochemical, functional, antinutritional and pasting properties of taro, rice, pigeonpea flours and their blends were determined and related to each other using Pearson correlation and Principal Component Analysis (PCA). Taro flour was significantly (P < 0.05) different from other flours due to its highest ash, crude fiber, lower fat and protein content and exhibited lowest L∗, ΔE, foaming capacity (FC) and highest WSI (water solubility index), WAC (water absorption capacity) and OAC (oil absorption capacity) as compared to rice and pigeonpea flour. Different blends were prepared incorporating the ratio of taro flour at 20 g/100 g, 30 g/100 g, 40 g/100 g, 50 g/100 g, 60 g/100 g levels with the blends consisting of equal proportions of rice and pigeonpea flour. Increased concentration of taro flour in the blends resulted in shifting of the blends towards the right positive score of first principal component (PC1) thereby indicating the detection of blends containing 40 g/100 g taro flour with an ease in the admixture of different flours. Taro flour contained higher oxalate, pasting temperatures (PT), peak viscosity (PV), trough viscosity and polyphenol content while lesser amount of phytate and lower setback viscosity than other flours.
236 citations
TL;DR: A microencapsulated β-cyclodextrin and trans-cinnamaldehyde complex (2.5g/100g) was incorporated into a multilayered edible coating made of chitosan and pectin this paper.
Abstract: A microencapsulated beta-cyclodextrin and trans -cinnamaldehyde complex (2 g/100 g) was incorporated into a multilayered edible coating made of chitosan and pectin. Fruits were washed, peeled and cut, coated, and stored at 4 °C in Ziploc ® trays with Ziploc ® lids for 15 days. Uncoated fruits served as controls. Coated fruits were firmer, maintained color, β-carotene content, and showed lower juice leakage ( P P trans -cinnamaldehyde was successful since it had no negative impact on the fruit's flavor. A parallel study evaluated the effect of packaging on the efficacy of the multilayered coating. Coated and uncoated fruits in trays were also covered with Saran ® wrap and plain cheese cloth (ambient conditions). The Ziploc ® trays with Ziploc ® lids were the best packaging method. The Layer-by-layer assembly with incorporation of microencapsulated antimicrobial was effective in extending shelf life and quality of fresh-cut papaya.
191 citations
TL;DR: In this article, tomato processing byproducts, together with unprocessed tomatoes were analyzed for several bioactive phytochemicals, like sterols, tocopherols, carotenes, terpenes, total and simple polyphenols.
Abstract: Tomato processing byproducts, together with unprocessed tomatoes were analyzed for several bioactive phytochemicals, like sterols, tocopherols, carotenes, terpenes, total and simple polyphenols. In addition, their radical scavenging capacity and reducing power were assayed. On a dry weight (DW) basis, tomato wastes contained significantly lower amounts of lycopene and increased amounts of β-carotene, tocopherols, sterols and terpenes, while their fatty acid profile was similar to that of unprocessed tomatoes. Tomato byproducts contained similar amount of total polyphenols and exhibited similar DPPH radical scavenging activity and ferric reducing power with tomatoes. Among 18 simple polyphenols determined by GC/MS, hydroxycinnamic acids predominated in whole tomatoes, while flavonoids predominated in tomato wastes with naringenin comprising 87% of flavonoids. As most of the phytochemicals determined exert antioxidant activities, tomato processing byproducts could be successfully utilized as functional ingredient for the formulation of antioxidant rich functional foods.
173 citations
TL;DR: Over the past few years, significant breakthroughs have occurred in the replacement of fish oil with plant oils in compounded fish feeds in order to reduce dependence on fish oil as well as reduce costs.
Abstract: Fish oil constitutes a major dietary ingredient in compounded fish feeds for carnivorous marine fish due to its essential fatty acid content, in particular omega-3 polyunsaturated fatty acids (n-3 PUFA). The issue of fish oil substitution in fish feeds has come to the forefront only recently, due to the release of recent data which indicates that the aquaculture industry uses 40 and 75% of the global production of fish meal and fish oil, respectively. Within the next decade fish oil production may not meet the required quantities for aquaculture, meaning that food grade fisheries which provide fish oil and fish meal have reached their limit of sustainability. Over the past few years, significant breakthroughs have occurred in the replacement of fish oil with plant oils in compounded fish feeds in order to reduce dependence on fish oil as well as reduce costs. All recent data, focussing on the benefits of replacing fish oil with plant oils in compounded fish feeds, are presented in this review.
173 citations
TL;DR: Lovastatin, γ-aminobutyric acid (GABA) and ergothioneine were analysed in mushrooms and the Pleurotus genus contained considerably high amount of ergothionine, which might be related to their beneficial effects.
Abstract: Lovastatin, γ-aminobutyric acid (GABA) and ergothioneine were analysed in mushrooms. Among fruiting bodies, Pleurotus ostreatus (Japan) and Agaricus bisporus contained the highest amount of lovastatin (606.5 and 565.4 mg/kg, respectively) whereas among mycelia, Cordyceps sinensis and Antrodia salmonea contained the highest (1365 and 1032 mg/kg, respectively). Among fruiting bodies, Flammulina velutipes and Boletus edulis contained the highest amount of GABA (229.7 and 202.1 mg/kg, respectively) whereas among mycelia, Cordyceps cicadae , C. sinensis and Agaricus blazei contained the highest (254.9, 220.5 and 200.4 mg/kg, respectively). Among fruiting bodies, Pleurotus citrinopileatus , P. ostreatus (Korea), P. ostreatus (Taiwan) and Pleurotus salmoneostramineus contained the highest amount of ergothioneine (2850.7, 1829.4, 1458.4 and 1245.0 mg/kg, respectively) whereas among mycelia, Pleurotus eryngii contained the highest (1514.6 mg/kg). Ergothioneine was detected in all samples. However, the Pleurotus genus contained considerably high amount of ergothioneine. Overall, these results might be related to their beneficial effects.
170 citations
TL;DR: In this paper, the effect of different drying treatments on the antioxidant activity of mango peel and seed was studied and it was shown that Oven-drying at 70°C (with static or forced air) was the treatment that had the most negative effect.
Abstract: The aim of this work was to study the effect of different drying treatments on the antioxidant activity of mango peel and seed. Freeze-drying allowed the peel (when extraction was carried out with ethanol:water) and seed to be stabilised without diminishing their antioxidant activity. In addition, this treatment improved mango peel’s antiradical capacity against ABTS•+ (in ethanol:water), as well as the capacity of the seed to scavenge free radicals and to inhibit the lipid peroxidation. Oven-drying at 70 °C (with static or forced air) was the treatment that had the most negative effect on the antioxidant capacity of mango peel (when extraction was carried out with ethanol) and seed. Because the effect of drying methods on the phenol and anthocyanin content of mango peel or seed is related to antioxidant activity (with a moderately strong significant correlation, p
TL;DR: The effect of different fibers, added individually or in combination, to improve the functional properties of gluten-free layer cakes was examined in this paper, where soluble (inulin and guar gum), and insoluble (oat fiber) fibers were used to replace up to 20% of rice flour in the formulation.
Abstract: The effect of different fibers, added individually or in combination, to improve the functional properties of gluten-free layer cakes was examined. Soluble (inulin and guar gum), and insoluble (oat fiber) fibers were used to replace up to 20% of rice flour in gluten-free layer cakes formulation. The incorporation of fibers increased the batter viscosity, with the exception of inulin. Fiber enriched gluten-free cakes containing blends of oat fiber–inulin resulted in improved specific volume. Significantly brighter crust and crumb was obtained in the presence of fibers, excepting the crumb of oat–guar gum containing cake. Fibers and its blends increased the crumb hardness; but the smallest effect was observed with the addition of oat, individually or combined with inulin. Enriched cakes increased significantly their dietary fiber content, which was connected to the nature of the fibers added. Fibers significantly affected the in vitro hydrolysis of starch fractions, being the most pronounced effect the decrease in the slowly digestible starch. Overall combination of oat fiber–inulin resulted in better gluten-free cakes.
TL;DR: In this paper, three different pre-treatments were applied on grape seeds: pulsed electric fields (PEF), highvoltage electrical discharges (HVED) and grinding (180 W, 40 S).
Abstract: The polyphenols extraction from grape seeds was studied. In order to increase the polyphenols yield and the extraction kinetics, three different pre-treatments were applied on grape seeds: pulsed electric fields (PEF) (8–20 kV/cm, 0–20 ms), high-voltage electrical discharges (HVED) (10 kA/40 kV, 1 ms) and grinding (180 W, 40 s). These electrical treatments can damage cell membranes (PEF/HVED) and cell walls (HVED) thus accelerating the compounds extraction but have different effects on the product fragmentation. The diffusion was then performed after pre-treatment with a mixture of water and ethanol. The PEF efficiency was improved when the treatment was performed at 50 °C in the presence of ethanol. PEF-assisted diffusion was then compared to HVED-assisted diffusion and to diffusion of ground grape seeds. These two pre-treatments increased both the extraction kinetics and the maximum polyphenols yield. For both cases, the final polyphenols content was 9 g GAE/100 g DM after 15 min of extraction with grinding and after 60 min with HVED. When PEF were applied in a suspension containing ethanol, the maximum polyphenols yield was also reached after 60 min. The subsequent solid–liquid separation was faster with PEF as compared to ground and HVED-treatments.
TL;DR: Inhibitory mode and anti-diabetic activities of the Carols muscadine extracts on the α-glucosidase and pancreatic lipase were investigated in this paper.
Abstract: Inhibitory mode and anti-diabetic activities of the Carols muscadine extracts on the α-glucosidase and pancreatic lipase were investigated. The IC 50 values of the muscadine and its seed methanolic extracts against the α-glucosidase were 1.92 and 1.53 mg/mL, and those against the lipase were 34.41 and 8.63 mg/mL, respectively, which indicated the muscadine possessed the strong anti-diabetes activity. Particularly, the ethyl acetate (EtOAc) extract fractions exhibited the highest inhibitory activities against both enzymes. Since most of the phenolic compounds existed in the EtOAc fractions, it is suggested that phenolic compounds may be the main source against the α-glucosidase and pancreatic lipase. Twelve individual phenolics were identified by HPLC-MS. Ellagic acid and quercetin exhibited much stronger anti-diabetic activities among the selected phenolic standards. Besides, the extracts and the phenolic standards obeyed the competitive mode in their enzymatic inhibitions.
TL;DR: The effect of the addition of passion fruit peel powder (PFPP) on the fermentation kinetics and texture parameters, post-acidification and bacteria counts of probiotic yoghurts made with two milk types were evaluated during 28 days of storage at 4 °C as discussed by the authors.
Abstract: The effect of the addition of passion fruit peel powder (PFPP) on the fermentation kinetics and texture parameters, post-acidification and bacteria counts of probiotic yoghurts made with two milk types were evaluated during 28 days of storage at 4 °C. Milks were fermented by Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus (CY340), and one strain of probiotic bacteria: Lactobacillus acidophilus (L10 and NCFM), Bifidobacterium animalis subsp. lactis (Bl04 and HN019). The addition of PFPP reduced significantly fermentation time of skim milk co-fermented by the strains L10, NCFM and HN019. At the end of 28-day shelf-life, counts of B. lactis Bl04 were about 1 Log CFU mL–1 higher in whole yoghurt fermented with PFPP regarding its control but, in general, the addition of PFPP had less influence on counts than the milk type itself. The titratable acidity in yoghurts with PFPP was significantly higher than in their respective controls, and in skim yoghurts higher than in the whole ones. The PFPP increased firmness, consistency (except for the NCFM strain of L. acidophilus) and cohesiveness of all skim yoghurts. The results point out the suitability of using passion fruit by-product in the formulation of both skim and whole probiotic yoghurts.
TL;DR: In this paper, the development of nutraceutical foods with a low glycemic index is necessary because of the problem of overweight and obesity in Mexico's principal public health problems Because of this problem, the research of nut raceutical foods having a low GI is necessary.
Abstract: The Mexican government declared that overweight and obesity are Mexico’s principal public health problems Because of this problem the development of nutraceutical foods with a low glycemic index is necessary Cookies with unripe banana flour (UBF) were prepared with very few ingredients in the formulation to avoid fat and digestible carbohydrates Proximate composition and starch digestibility were carried out Moisture and dietary fiber content increased, but protein and fat decreased when the UBF level increased in the cookie Total starch in cookies added with UBF increased when this ingredient was increased in the formulation A similar pattern was found for available and resistant starch Resistant starch content is important due to the beneficial effects associated with its fermentation in the colon Hydrolysis percentage and predicted glycemic index decreased when the UBF increased in the composite that is related with the resistant starch content When the amount of UBF was increased in the cookies, the rapidly digestible starch decreased and the slowly digestible starch increased Addition of UBF to simple formulation for cookie preparation is important to obtain a product with high level of indigestible carbohydrates
TL;DR: Gel electrophoresis patterns of porcine muscle displayed that different thawing methods did not induce obvious protein aggregates and fragments, and demonstrated all the thawed methods could cause porcines lipid and protein oxidation.
Abstract: The objective of the present study was to elucidate the physicochemical changes and protein oxidation of porcine longissimus muscle as influenced by different thawing methods. Five kinds of thawing methods, comprising of refrigerator thawing (RT, 4 °C), ambient temperature thawing (AT, 20 °C), water immersion thawing (WT, 14 °C), lotic water thawing (LT, 9 °C), and microwave thawing (MT), were used. There were significant effects on the porcine meat quality due to different thawing methods. RT had the least quality loss and the physicochemical characteristics of pork were closer to fresh muscle than the other thawing methods. MT significantly increased thawing loss, cooking loss, cutting force, carbonyl content, and TBARS (thiobarbituric acid-reactive substances) value, but decreased a* value and Ca-, K-ATPase activities (P
TL;DR: In this paper, the effect of variable values on pectin yield and uronic acid content of cacao pod husks was examined. But none of the variables had a significant effect on the uronic acids content, and there was a lack of fit of the model to the urea acid content.
Abstract: Variables that influence the citric-acid extraction of pectins from cacao pod husk were examined. A screening study tested the main parameters influencing pectin yield and uronic acid content by a factorial fractional 3 3−1 design. Further, response surface methodology was applied using a central composite design to examine the effect of a greater region of variable values on pectin yield and uronic acid content. The yield was optimized by increasing the temperature and time. None of the variables had a significant effect on the uronic acid content, and there was lack of fit of the model to the uronic acid content. From the fitted model, extraction conditions with aqueous citric acid at pH 3.0 for 95 min at 95 °C provided a predicted yield of approximately 9.0 g/100 g dry cacao pod husks. The obtained experimental value for the yield was 10.1 ± 0.3 g/100 g dry cacao pod husks, with the pectins containing 65.1 ± 0.8 g uronic acid/100 g fraction, DE 40.3% and DA 15.9%. At 5 g/100 g aqueous solution, the fraction behaved as a concentrated solution and presented a non-Newtonian shear-thinning behavior, well described by Cross Model. Additionally, the fraction formed gels at acidic pH and high sucrose content.
TL;DR: In this article, the effects of various domestic cooking methods, such as boiling, microwaving and baking on total phenolics, flavonoids, lutein, anthocyanins and antioxidant activities in 5 cultivars and 9 advanced selections with different skin and flesh colors after 6 months of storage.
Abstract: Potato tubers, which are one of the richest sources of antioxidants, are always cooked before human consumption The objective of this study was to understand the effects of various domestic cooking methods, ie, boiling, microwaving and baking on total phenolics, flavonoids, flavonols, lutein, anthocyanins and antioxidant activities in 5 cultivars and 9 advanced selections with different skin and flesh colors after 6 months of storage The three cooking methods reduced the levels of these compounds and the percentage of DPPH (2,2-Diphenyl-1-pikryl-hydrazyl) radical scavenging activity in all the cultivars and selections Boiling minimized these losses Red fleshed tubers contained more flavonoids, whereas purple tubers contained more flavonols Despite severe loss of these compounds due to cooking, both the flesh types retained larger amounts of all these compounds due to higher initial levels Decline in the radical scavenging activity is directly related to loss of these compounds due to cooking treatments in all white and colored flesh tubers Red and purple fleshed tubers exhibited greater radical scavenging activity than yellow and white fleshed tubers after each of the cooking treatments Correction procedures were introduced to exclude interfering compounds (ascorbic acid, other oxidizing agents and reducing sugars) in Folin-Ciocalteu Reagent (FCR) assay of estimating total phenolics in potato
TL;DR: In this article, a study was made of the structure, texture, appearance, colour and consumer sensory analysis of low-sucrose muffins in which the sucrose had been totally or partially replaced by a sucralose:polydextrose mixture (1:1012).
Abstract: A study was made of the structure, texture, appearance, colour and consumer sensory analysis of low-sucrose muffins in which the sucrose had been totally or partially replaced (25%, 50%, 75%) by a sucralose:polydextrose mixture (1:1012). The structural characteristics of the muffin batters and of the baked muffins were studied through rheometry, microscopy, image analysis and texture analysis. The replacement of sucrose decreased the viscosity, viscoelasticiy and specific gravity of the raw muffin batter. The evolution of the batter’s viscoelastic properties during heating reveals a decrease in the thermosetting temperature with sucrose replacement. These changes in the batter were associated with a muffin with less height, hardness, springiness, cohesiveness, chewiness and resilience and fewer air cells than the control. For 50% sucrose replacement, the appearance, colour, texture, flavour and sweetness and general acceptability were similar to those of the control. Significantly less acceptable muffins were obtained with 100% sucrose replacement.
TL;DR: In this paper, the effect of domestic heating on mechanical extraction yield, quality and antioxidant properties of cold-pressed rice bran oil (RBO) was investigated, and it was found that hot air and microwave heating were the most effective methods for stabilization of RBO.
Abstract: The effect of stabilization of rice bran by domestic heating on mechanical extraction yield, quality and antioxidant properties of cold-pressed rice bran oil (RBO) was investigated. The highest extraction yield was found in hot air heating with 5.53 g/100 g bran, followed by microwave heating (4.81 g/100 g bran), roasting (4.77 g/100 g bran) and steaming (3.41 g/100 g bran). Hot air and microwave heating were the most effective methods for stabilization of rice bran ( P P P > 0.05). In conclusion, the stabilization of rice bran by domestic heating could be applied to RBO extraction prior to pressing to improve oil extraction yield, quality and antioxidant properties of cold-pressed RBO.
TL;DR: In this paper, six green tea powders (GTPs) were prepared from green tea with superfine grinding process and their main quality components were determined by chemical methods and the scavenging effects of GTPs on ·OH and O2.
Abstract: Six Green tea powders (GTPs) were prepared from green tea with superfine grinding process. Their main quality components were determined by chemical methods and the scavenging effects of GTPs on ·OH and O2.− in vitro were evaluated by using deoxyribose assay and xanthine oxidase method, respectively. The results indicated that tea polyphenols and catechins contents decreased, while the contents of water-soluble carbohydrates in GTPs increased markedly, and no significant difference in amino acids and caffein with the decrease in particle size during superfine grinding, which benefited to reduce bitterness and preserve briskness of GTPs. Meanwhile, superfine grinding increased extraction of TPS markedly, which could lead to more potent scavenging capacity of GTPEs on ·OH. Based on the above analysis, it suggested that superfine grinding time should be controlled within 30–50 min, with ideal parameters of GTP: X: 4.93–4.75%, d50: 20.3–13.5 μm, ρbulk: 0.323–0.297 kg/m3, ρtapped: 0.666–0.614 kg/m3. Under this condition, we could prepare GTP with green and bright color, narrower and more uniform particle size distribution, as well as possessing more food processing property.
TL;DR: In this article, the authors analyzed the phenolic content, antioxidant and antidiabetic properties of methanolic extract of raw and traditionally processed food ingredients, including cereals, legumes, oil seeds and vegetables.
Abstract: Certain indigenous foods commonly consumed by Kenyan vulnerable groups (the malnourished; children under 5 years of age; pregnant and lactating women; malnourished adults in cases of vitamin or mineral deficiencies, TB, diabetes, cancer, AIDS; refugees; orphans the elderly and the disabled) are not yet evaluated for phenolic content and health relevant functionality. The present study was therefore designed to analyze the phenolic content, antioxidant and antidiabetic properties of methanolic extract of raw and traditionally processed food ingredients. The total phenolic contents of the cereals, legumes, oil seeds and vegetables were ranged from 0.41 to 3.00 g/100 g DM. Amaranth grain ( Amaranthus cruentus ) and drumstick leaves ( Moringa oleifera ) exhibited significantly higher phenolic content than the other samples. The methanolic extract of the investigated samples showed promising levels of DPPH radical scavenging activity (81–89%); ferric reducing/antioxidant power (FRAP, 44–744 mmolL −1 Fe[II]/g extract DM); α-amylase (10–45%) and α-glucosidase (13–80%) inhibition activities. The food ingredients with high phenolic content exhibited relatively higher antioxidant and antidiabetic activities. The results indicate that soaking + cooking is the mild processing method to preserve the phenolic compounds and their health relevant functionality in the presently investigated cereal, legume and oil grains, while cooking is suitable treatment for vegetables.
TL;DR: In this paper, the antimicrobial properties of multilayer biodegradable cellulose-based films, incorporating sorbic acid (SA) as antimicrobial agent, have been obtained.
Abstract: Biodegradable bacterial cellulose (BC) based films, incorporating sorbic acid (SA) as antimicrobial agent, have been obtained. Monolayer films, prepared using powdered BC (BCP) and poly(vinyl) alcohol (PVA), were coated with BC membrane to obtain multilayer films. Tests indicated that both SA and BCP concentration influenced sensitivity to water, release rate and antimicrobial ability of mono and multilayer films. Swelling degree, water vapour permeability and water solubility increased with SA content, but decreased with BCP addition. However in case of multilayer films, water solubility was negligible. Colour measurements indicated no degradation of SA during film preparation. The release of SA was faster when BCP concentration was higher but significantly slower, as a consequence of formed crystals dissolution, when antimicrobial concentration was increased. Furthermore, compared to the results for the monolayer films, an important decrease of SA release rate through the multilayer films was determined. The antimicrobial effect was tested against Escherichia coli K12-MG1655. The results obtained indicated that the new biocomposite films could be promising antimicrobial food packaging materials.
TL;DR: Green banana flour (GBF) was used to partially substitute cassava starch in two types of snacks, viz. fish cracker (FC) and cassava cracker(CC).
Abstract: Green banana flour (GBF), as a functional ingredient, was used to partially substitute cassava starch in two types of snacks, viz. fish cracker (FC) and cassava cracker (CC). It is observed that use of GBF increased the nutritional value including enhancement of dietary fiber, essential minerals, polyphenol content, antioxidant capacity and decreased oil content to varying degrees depending on the substitution level in these two crackers. However, its use compromised the textural properties in terms of the linear expansion ratio, crispness, bulk density, porosity and color. Sensory evaluation showed that the products with not more than 40 g substitution level by GBF from 100 g cassava starch in CC and not more than 15 g in FC were acceptable by the panelists.
TL;DR: In this paper, the effect of ultra high pressure homogenization (UHPH) at 200 and 300 MPa in combination with different inlet temperatures (55, 65 and 75 MPa) on soymilk was studied.
Abstract: The effect of ultra high pressure homogenization (UHPH) at 200 and 300 MPa in combination with different inlet temperatures (55, 65 and 75 °C) on soymilk was studied. UHPH-treated soymilk was compared with the base product (untreated), with pasteurized (95 °C for 30 s) and with ultra high temperature (UHT; 142 °C for 6 s) treated soymilks. Microbiological (total aerobic meshophilic bacteria, aerobic spores, and Bacillus cereus ), physical (dispersion stability and particle size distribution) and chemical (lipoxygenase activity, hydroperoxide index and trypsin inhibitor activity) parameters of special relevance in soymilk were studied. Microbiological results showed that pressure and inlet temperature combination had a significant impact on the lethal effect of UHPH treatment. While most of UHPH treatments applied produced high quality of soymilks better than that pasteurized, the combination of 300 MPa and 75 °C produced a commercially sterile soymilk. UHPH treatments caused a significant decrease in particle size resulting in a high physical stability of samples compared with conventional heat treatments. UHPH treatment produced lower values of hydroperoxide index than heat treated soymilks although trypsin inhibitor activity was lower in UHT-treated products.
TL;DR: In this article, the effects of γ-irradiation treatment on the structure and physicochemical properties of maize starch granules were studied, and the results showed that peak, trough, final, and setback viscosities were significantly reduced, whereas the solubility was increased following irradiation.
Abstract: Maize starch powder was exposed to a 60 Co source (0, 1, 2, 5, 10, 20, 50, 100, 200, or 500 kGy) and the effects of γ-irradiation treatment on the structure and physicochemical properties of the starch granules were studied. The results showed that peak, trough, final, and setback viscosities were significantly reduced, whereas the solubility was increased following irradiation. Gelatinization temperature and enthalpy decreased significantly when the dose is higher than 50 kGy. On the surface, the starch granules did not display any visible physical change up to a 500 kGy dose was. X-ray diffraction (XRD) analysis showed that the relative crystallinity of starch decreased slightly, and the starch exhibited an A-pattern without any change. Fourier transform infrared (FTIR) spectral intensity at 1018 cm −1 increased with the irradiation dose up to 200 kGy. Irradiation dose was positively correlated with solubility and negatively correlated with relative crystallinity. There were high positive correlations between thermal properties and pasting properties.
TL;DR: In this article, the effect of adding winter savory (Satureja montana L.) essential oil (EO) at concentrations of 7.80, 15.60 and 31.25μl/g on color and lipid oxidation (TBARS) in mortadella-type sausages formulated with different sodium nitrite (NaNO2) levels (0, 100 and 200μ/kg) and stored at 25°C for 30 days.
Abstract: This study aimed to evaluate the effect of adding winter savory (Satureja montana L.) essential oil (EO) at concentrations of 7.80, 15.60 and 31.25 μl/g on color and lipid oxidation (TBARS) in mortadella-type sausages formulated with different sodium nitrite (NaNO2) levels (0, 100 and 200 mg/kg) and stored at 25 °C for 30 days. The EO was extracted by hydrodistillation and analyzed by gas chromatography–mass spectrometry (GC–MS). Twenty-six chemical compounds were identified; the most prominent of which were thymol (28.99 g/100 g), p-cymene (12.00 g/100 g), linalool (11.00 g/100 g) and carvacrol (10.71 g/100 g). Among the nitrite levels tested, a concentration of 100 mg/kg of sodium nitrite appeared to be sufficient for the formation of the characteristic red color. The use of EO at concentrations exceeding 15.60 μl/g adversely affected the color of the product by reducing redness (a∗) (p ≤ 0.05) and increasing yellowness (b∗ h∗). The EO antioxidant activity was confirmed by β-carotene bleaching method and DPPH assay. Reduced values of thiobarbituric acid reactive substances (TBARS) (p ≤ 0.05) were observed in mortadellas formulated with the lowest concentrations of EO without added nitrite. This significant effect on lipid oxidation was also observed in samples containing EO and reduced amounts of sodium nitrite. The results suggest possible benefits from the combined use of EOs and minimal amounts of sodium nitrite in cured meat products.
TL;DR: In this paper, high hydrostatic pressure (HHP) was applied to fruit smoothies at moderate temperatures to investigate the effect of HHP on the antioxidant capacity of the smoothies compared to fresh and HHP-450 samples.
Abstract: Fruit smoothie samples were thermally (P70 > 10 min) or high hydrostatic pressure (HHP) processed (450 MPa/20 °C/5 min or 600 MPa/20 °C/10 min) and the total antioxidant capacity (TAC), levels of antioxidant groups [total phenols (TP), anthocyanins and ascorbic acid], instrumental colour, polyphenol oxidase (PPO) enzyme activity and dissolved oxygen were examined over a storage period of 10 h at 4 °C Thermal processing of smoothies reduced (p < 0001) TAC and TP values, ascorbic acid and L and a colour attributes (lightness and redness respectively) compared to fresh and HHP-450 processed samples Conversely, it did result in complete inactivation of PPO enzyme, with no activity detected Of the HHP treatments, HHP-450 samples had higher (p < 0001) levels of total antioxidant, phenols and anthocyanin content than HHP-600 samples However, the latter was more effective in reducing (p < 0001) the endogenous enzyme activity of the smoothies Ascorbic acid content degraded over the storage for all smoothies HHP-600 samples had high initial values, which declined slowly over storage, while thermal samples had the lowest initial value (05 h) that fell below detectable limits by 10 h Despite these data, less pronounced effects were observed for storage No significant effects were observed for total anthocyanin and phenolic contents as well as L and colour change (ΔE) variables Overall, HHP processing of smoothies at moderate temperatures may be a suitable alternative to traditional thermal processing
TL;DR: In this article, a study was conducted to optimize millet-based composite flours for the preparation of breads, and the results of this sensory analysis showed that the acceptability of bread samples prepared from composite fours was almost equal to the wheat bread.
Abstract: Millets have various nutrition qualities, and have rightly been called “nutri-cereals”. Wheat is traditionally used in breads, and consumption of millet can be increased by replacing wheat by millet to a required extent. The aim of this study was to optimize millet-based composite flours for the preparation of breads. Barnyard-millet and wheat composite flour (BWCF) was formulated and prepared by mixing 61.8 g/100 g barnyard-millet, 31.4 g/100 g wheat and 6.8 g/100 g gluten. Another formulation barnyard-millet, finger-millet, proso-millet and wheat composite flour (BFPWCF) was developed using 9.1 g/100 g barnyard, 10.1 g/100 g finger-millet, 10.2 g/100 g proso-millet and 69.6 g/100 g wheat. Bread samples were prepared using two composite flours and wheat flour, which was used to compare the quality of the breads prepared from the composite flours. A sensory study was conducted for analysis of acceptability of these samples. The analysis of this sensory study was conducted using fuzzy logic. The results of sensory analysis showed that the acceptability of bread samples prepared from composite flours was almost equal to the wheat bread.