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Volume 26 (2022): Edition 1 (June 2022)

Volume 25 (2021): Edition 2 (December 2021)

Volume 25 (2021): Edition 1 (June 2021)

Volume 24 (2020): Edition 2 (December 2020)

Volume 24 (2020): Edition 1 (June 2020)

Volume 23 (2019): Edition 2 (December 2019)

Volume 23 (2019): Edition 1 (June 2019)

Volume 22 (2018): Edition 2 (December 2018)

Volume 22 (2018): Edition 1 (August 2018)

Volume 21 (2017): Edition 2 (December 2017)

Volume 21 (2017): Edition 1 (June 2017)

Volume 20 (2016): Edition 2 (December 2016)

Volume 20 (2016): Edition 1 (June 2016)

Volume 19 (2015): Edition 2 (December 2015)

Volume 19 (2015): Edition 1 (July 2015)

Volume 18 (2014): Edition 2 (December 2014)

Volume 18 (2014): Edition 1 (June 2014)

Volume 17 (2013): Edition 2 (December 2013)

Volume 17 (2013): Edition 1 (June 2013)

Détails du magazine
Format
Magazine
eISSN
2344-150X
Première publication
30 Jul 2013
Période de publication
2 fois par an
Langues
Anglais

Chercher

Volume 25 (2021): Edition 1 (June 2021)

Détails du magazine
Format
Magazine
eISSN
2344-150X
Première publication
30 Jul 2013
Période de publication
2 fois par an
Langues
Anglais

Chercher

15 Articles
access type Accès libre

Essential Oil of Cymbopogon Citratus Grown in Umuahia: A Viable Candidate for Anti-Inflammatory and Antioxidant Therapy

Publié en ligne: 28 Jun 2021
Pages: 1 - 14

Résumé

Abstract

The essential oils of Cymbopogon citratus (EOCC) has found use in medicine, food and chemical industry. This study attempts to provide evidence of its suitability for antioxidant and anti-inflammatory therapy. Total phenol and total flavonoid of EOCC was 49.83±0.39mg GAE/g of extract and 352.82±3.45 µg QEC/g of extract respectively. Gas chromatography-mass spectrometry (GC-MS) analysis of its essential oil (EOCC) showed 25 peaks with myrcenyl acetate (9.703%), caryophyllene (8.997%), citronella (6.383%) been the most abundant. The in vitro anti-inflammatory assay using human red blood cell (HRBC) membrane stabilization shows that at 200µg/mL, the percentage inhibition of EOCC was significantly higher compared to diclofenac both for heat-induced and hypotonic induced haemolysis. 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays showed a comparable and dose-dependent increase from 50 to 400 μg/mL in relation to vitamin C. Half maximal inhibitory concentration (IC50) of EOCC (73.16±12.89 μg/mL and 656.01±0.01 μmol Fe (II)/L) was remarkably higher compared to that of vitamin C (69.09±4.52 μg/mL and 246.79±0.01 μmol Fe (II)/L) both for DPPH and FRAP assays respectively. In conclusion, results from this study establish preliminary evidence on the therapeutic potential of EOCC in managing inflammation and oxidative stress caused by free radicals.

Mots clés

  • Antioxidant
  • Anti-inflammatory
  • Essential oils
  • Cymbopogon
access type Accès libre

A Comparative Analysis of Different Varietal of Fresh and Dried Figs by In Vitro Bioaccessibility of Phenolic Compounds and Antioxidant Activities

Publié en ligne: 26 Jun 2021
Pages: 15 - 30

Résumé

Abstract

Varietal and sun-drying effects on phenolic compounds and their antioxidant activity were investigated during the in vitro gastrointestinal digestion of fresh and dried figs. The total phenolic compounds (phenolic, flavonoids, and proanthocyanidin) and their antioxidant activity (ferric reducing power; free radical scavenging activity DPPH, and phosphomolybdenum test) were evaluated before and after digestion. The total phenolic compounds and the antioxidant capacities of fresh and dried figs obtained before digestion were significantly (p < 0.05) higher than those obtained after digestion. A significant decrease (p < 0.05) of phenolic compounds and their antioxidant activity was observed during different digestion phases (oral phase > gastric phase > intestinal phase). A positive correlation was found between the total phenolic compounds and the antioxidant activity tested for both fresh and dried figs. Furthermore, the results showed that the digestion has no effect on the total phenolic compounds; however, a negative influence of the pH and the enzymes was observed on these compounds and their antioxidant activity. During in vitro gastrointestinal digestion, the varietal and the sun-drying has no significant effect on the phenolic compounds and their antioxidant activity. Likewise, the fresh or dry variety kept a high content before and after the digestion.

Mots clés

  • gastrointestinal digestion
  • figs
  • phenolic compounds
  • antioxidant activity
  • varietal effect
  • sun-drying effect
access type Accès libre

Effect of Thermal and Non-Thermal Processing on the Nutritional Composition, Pasting Profile and Protein Secondary Structure of Alfalfa

Publié en ligne: 28 Jun 2021
Pages: 31 - 42

Résumé

Abstract

Alfalfa is an unconventional alternative legume and its potentiality for utilization can be improved by processing. In this study, alfalfa seeds were processed by different thermal and non-thermal techniques and evaluated for their physical properties, colour characteristics, nutritional composition, pasting profile and protein secondary structure. The results were analyzed using Principal Component Analysis to elucidate the effect of processing. Colour of the flour was more affected by thermal processing in comparison to non-thermal processing. Nutritional composition of alfalfa flour was significantly affected by germination as compared to other methods and germinated flour showed an increase in the protein content. All the processing treatments resulted in improving the pasting properties except for germination. Particularly, marked improvement in the pasting properties was observed by wet heat processing and soaking. ATR-FTIR exhibited change in the secondary structure of the protein as a result of processing and showed the dominance of intermolecular β-sheets in extrusion, germination and microwave treated flour and formation of anti-parallel β-sheets after dry heat processing. Wet heat processing and soaking treatment can be employed for alfalfa for enhancing its techno-functionality.

Mots clés

  • alfalfa
  • ATR-FTIR
  • pasting
  • processing
access type Accès libre

Effect of Brachystegia Eurycoma Flour Addition on the Physicochemical Properties of Whole Millet Flour and the Sensory Attributes of its Gluten-Free Bread

Publié en ligne: 28 Jun 2021
Pages: 43 - 52

Résumé

Abstract

This study evaluated the effect of addition of Brachystegia eurycoma flour (BEF), a natural source of hydrocolloids, on the physicochemical properties of whole millet flour (WMF) and the sensory attributes of its gluten-free bread. BEF and sodium carboxylmethyl cellulose (a reference hydrocolloid) were added to WMF at 1.5 and 3% proportions, and breads were baked from the blends. Wheat flour (100%CWF) bread served as the control. Amylose level decreased significantly (p < 0.05), while water absorption capacity, peak and final viscosities of the blends increased with increasing proportion of BEF. The 100%CWF bread had better sensory qualities than WMF-BEF breads. Hence, BEF improved the physicochemical properties of WMF-BEF blend, but did not alter the sensory qualities of its gluten-free bread.

Mots clés

  • Whole millet flour
  • Gluten-free bread
  • Celiac disease
  • Sensory qualities
access type Accès libre

Evaluation of Flours from Ancient Varieties of Wheat (Einkorn, Emmer, Spelt) used in Production of Bread

Publié en ligne: 28 Jun 2021
Pages: 53 - 66

Résumé

Abstract

The study investigates rheological properties of dough and baking process made from flour obtained by milling grains from ancient varieties of wheat (einkorn, emmer and spelt), compared to common wheat flour dough (Arkadia variety). The findings show that einkorn flour dough and emmer flour dough present poor tolerance to mechanical processing and prolonged fermentation. These types of dough should be mixed through relatively short, and fermentation time should not exceed 80 minutes for einkorn dough and 45 minutes in the case of emmer dough. In the case of spelt flour dough, the optimum duration of mechanical processing and fermentation amounted to 10 minutes and 60 minutes, respectively. In terms of technological and baking parameters, spelt flour was most similar to the flour obtained by milling conventional wheat, and the superiority of the former was in fact identified in the case of selected factors. A one-stage method was used in the baking process and the bread was then subjected to organoleptic and physicochemical assessments and to texture profile analysis (TPA). Measurements were also performed to determine the indicators reflecting the quality of the baking processes, including dough yield, baking loss and bread yield. The physical parameters of the bread produced were significantly related to the wheat variety. The loaves made from einkorn and spelt flour were of good quality, comparable to the bread made from the conventional wheat, while their baking quality indicators were satisfying. Bread dough made from emmer flour did not meet the required parameters mainly related to the organoleptic assessment and selected physical properties of the bread crumb. However, the one-stage production method should not be applied to doughs made from emmer flour. Given the specific characteristics of the breads produced from the ancient wheat varieties, including their pleasant taste and aroma, as well as attractive colour in the case of einkorn bread, these baked products may be an interesting addition to the assortment of breads on offer from bakeries, restaurants and agritourist farms.

Mots clés

  • einkorn
  • emmer
  • spelt
  • dough rheology bread baking
  • physicochemical properties of bread
  • TPA
access type Accès libre

Bioactive, Antioxidant and Antidiabetic Properties of Cooked and Uncooked Irish Potato (Solanum Tuberosum)

Publié en ligne: 28 Jun 2021
Pages: 67 - 73

Résumé

Abstract

Potatoes are considered very important staple and antioxidant-rich tubers in human diet. The present study evaluated the bioactive, antioxidant, antidiabetic and inhibition of lipid peroxidation properties of cooked and uncooked Irish potatoes. The samples were subjected to total phenolic (TPC), total antioxidant capacity (TAC), total flavonoids (TFC), ascorbic acid (AsA) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity analyses using spectrophotometric method. Also Fe2+-induced lipid peroxidation, α-glucosidase and α-amylase inhibition were assayed. The results revealed that there is no significant (p < 0.05) difference in TPC and TAC of the potatoes samples but there was a significant (p < 0.05) enhancement in TFC and reduction in AsA of the cooked potatoes. There is also dose-dependent inhibition in DPPH and α-glucosidase and α-amylase enzymes. The IC50 revealed that cooked sample has significant higher (p < 0.05) inhibition in the enzymes assay. The lipid peroxidation was also reduced upon incubation with Irish potato samples but higher inhibition was exhibited by the cooked potato. In conclusion, this study has shown that Irish potato can be a good functional food in the management of diseases.

Mots clés

  • Phenolics
  • Flavonoid
  • α-glucosidase
  • α-amylase
  • Lipid peroxidation
access type Accès libre

Evaluation of Crystalline Cellulose of Corn Straw through Different Pretreatments Via X-Ray Diffraction, Scanning Electron Microscopy and Infrared Spectroscopy

Publié en ligne: 28 Jun 2021
Pages: 74 - 82

Résumé

Abstract

Waste recycling is beneficial not only for the environment but also for the economy and the society at large. Corn stalks, the most abundant crop waste, are processed with oven drying, steaming, complex enzymatic hydrolysis (cellulase, xylanase, β-glucanase and pectinase), and fermentation (by Candida utilis and Pachysolen tannophilus), were analyzed via X-ray diffraction, Scanning Electron Microscopy (SEM) and Infrared Spectroscopy (IR). The results indicated that thermophilic digestion destroyed glycosidic bonds and fibrous crystal have a significant effect on the degradation of the corn stalks, while complex enzyme hydrolysis only slightly degraded fibrous crystal. Fermentation did not significantly reduce fibrous crystal. Therefore, our research suggested that thermophilic digestion is the appropriate way to increase the saccharification rate and feed yield of corn stalks.

Mots clés

  • Corn stalk
  • X-ray diffraction
  • Fibrous crystal
  • SEM and IR
access type Accès libre

Ethanolic Extracts from Agro-Industrial Co-Products Enhance Oxidative Stability of Candelilla Wax or Celluloses Derivatives Oleogels

Publié en ligne: 28 Jun 2021
Pages: 83 - 92

Résumé

Abstract

Ethanol oleoresins obtained from orange peel, pea pod, or pomegranate peel were employed to enrich soybean oil before elaborating two types of oleogels, one made with candelilla wax, another made with a mixture of celluloses derivatives, in order to determine their effect on oleogel oxidative stability. Orange peel oleoresin obtained a higher amount of polyphenols as catechol acid equivalent (9.09 meq/g), as compared to pea pod oleoresin or pomegranate peel (8.80 and 8.55, respectively), although pomegranate peel presented the higher TEAC (1.67, twice than the other samples). Oleogels elaborated with celluloses were presented better oxidative stability (oxidative rancidity and peroxide index) as compared to samples elaborated with candelilla wax, since waxes minor constituents employed as oleogelators could promote prooxidant activity. Samples with pomegranate oleoresin presented enhanced oxidative stability. Candelilla wax has a more marked effect on the oleogels thermal properties of due to their influence on fatty acids crystallization, because in celluloses oleogels the mechanism of gelation does not imply the formation of a highly ordered secondary structure. This finding opens the possibility to, on one hand, use oleoresins to enhance the oxidative stability of oleogels; and on the other hand, to select the oleogelator, waxes, or celluloses, based on thermal properties and other aspects, depending on the further application of oleogel thinking in oleogel thermoreversible capacity.

Mots clés

  • Oleogel
  • candelilla wax
  • celluloses
  • oxidative stability
  • agro-industrial co-product
access type Accès libre

Preparation of Vitamin K2 Mk-7 in a Process of Fermentation of Different Seeds and Cereals by Bacteria Bacillus Subtilis

Publié en ligne: 28 Jun 2021
Pages: 93 - 104

Résumé

Abstract

In this study, 10 different plant materials (seeds/beans) were fermented by Bacillus subtilis var. natto. The influence of the process on vitamin K2 MK-7 content during different fermentation periods was assessed. Fermented plant samples were analyzed by the procedure using HPLC UV/DAD. The fermented sunflower seeds, mung beans and peas appeared to be the most promising plants, reaching values of K2 of 1080.18±55.11 µg/100g, 806.45±60.95 µg/100g and 636.92±59.86 µg/100g, respectively. The experiments showed that extending of the fermentation time to 5–6 days was favorable for the menaquinone-7 yield. The results show that almost all fermented seeds/beans, apart from soybean, can be good source of vitamin K2 MK-7 and represent a new perspective, especially in terms of lower the phytoestrogen content.

Mots clés

  • (natto)
  • bacterial fermentation
  • seeds/beans
  • HPLC/UV-DAD
  • menaquinone-7
  • vitamin K2 MK-7
access type Accès libre

Effect of Complexation Conditions on Microcapsulation of Lactobacillus Casei L61 in Gellan Gum–Chitosan Gels

Publié en ligne: 28 Jun 2021
Pages: 105 - 114

Résumé

Abstract

Probiotics have many benefits for human intestinal health. However, Probiotics have poor tolerance to gastric acid and bile salts of the stomach. Microencapsulation could confer protection to probiotic against harsh environments effectively. In this experiment, Lactobacillus casei L61 was embedded by extrusion with gellan gum and chitosan as wall material. The viable cells and encapsulation yield of microcapsules were used as the indexes, the optimum values of each factor were determined by a single factor experiment. Chitosan concentration 0.50%, chitosan pH 4.5, gellan gum concentration 1.50%, the volume ratio of bacterial suspension to gellan gum is 1:6, the volume ratio of bacterial gum to chitosan is 1:4, the stirring time is 40min.

Mots clés

  • Probiotics
  • Microencapsulation
  • L61
  • gellan gum
  • Chitosan
access type Accès libre

Effect of Alcalase on Antioxidant and Antihypertensive activities of Goat Milk Fermented by Lactobacillus Plantarum L60 and Lactobacillus Rhamnosus LR22

Publié en ligne: 28 Jun 2021
Pages: 115 - 122

Résumé

Abstract

Effect of alcalase addition, inoculum size, bacterial ratio, fermentation time and temperature on antioxidant and antihypertensive activities of goat milk fermented by Lactobacillus plantarum L60 and Lactobacillus rhamnosus LR22 was studied by using DPPH free radical scavenging rate, ACE inhibition rate, pH, and titer acidity as responses through single factor experiments. The results showed that the optimal alcalase addition, inoculum size, bacterial ratio, fermentation time and temperature was 0.15%, 5%, 1:1, 12h and 37°C, respectively, the probiotic goat milk prepared under these conditions had high antioxidant and antihypertensive activities.

Mots clés

  • goat milk
  • Alcalase
  • Lactobacillus plantarum Lactobacillus rhamnosus
  • antioxidant
  • ACE inhibition
access type Accès libre

Possibility of Reinforcement the Functional Potential of Vegetable Juices with the use of Novel Strain Lactiplantibacillus Plantarum EK11 Isolated from an Unconventional Fermented Food Matrix

Publié en ligne: 28 Jun 2021
Pages: 123 - 134

Résumé

Abstract

The study investigated the suitability of a novel strain Lactiplantibacillus plantarum EK11 for obtaining fermented tomato and beetroot juices with improved functional potential. EK11 had the capability of dynamic acidification of pasteurized vegetable beverages. The lowest values of pH were noted in juices after 48 h of fermentation with the probiotic L. plantarum 299v (pH=3.72±0.01 in beet juice and pH=3.43±.0.01 in tomato juice). The fermentation increased the lycopene content in tomato juices from 27.90±0.31µg mL−1 (after 24-h fermentation by strain EK11) to 116.86 ±0.19 µg mL−1 (final products obtained using strain 299v after 7-day cold storage). The process contributed to changes in the betanin and vulgaxanthin-I concentration in beetroot beverages. All fermented products exhibited antioxidative activity, i.e. 50% inhibition of 1,1-diphenyl-2-picrylhydrazyl free radicals. Moreover, three genes involved in the biosynthesis of bacteriocins were detected in the novel strain EK11, which exhibits functional and technological potential for the production of fermented foods.

Mots clés

  • lactic acid fermentation
  • bacteriocins
  • functional food
access type Accès libre

Optimization of Fermentation Conditions for Cell Envelope Proteinase Produced by Lactobacillus Plantarum LP69

Publié en ligne: 28 Jun 2021
Pages: 135 - 142

Résumé

Abstract

Cell-envelope proteinases (CEPs) can hydrolyze casein into functional peptides, which is beneficial to the health of the host. The single factor experiment screened out that the optimal conditions for CEP production by Lactobacillus plantarum LP69 were 37°C, 20h, initial pH of 7, and optimal inoculation amount of 5%. The best conditions for this experiment were obtained by orthogonal experiment: time 22h, temperature 39°C, initial pH value of 6, and inoculation amount of 5%. Under this culture condition, the target protease activity of Lactobacillus plantarum LP69 reached 22.31±0.82U/mL, the protein content was 19.07±0.36mg/mL, and the specific activity was 1.17±0.06U/mg. The specific activity significantly increased by 15.8% compared with the control (p<0.05).

Mots clés

  • cell-envelope proteinases
  • fermentation optimization
  • Orthogonal experiment
access type Accès libre

Chemical Characteristics of Limousine Beef Depending on Finishing Diets and Muscle Type of Meat

Publié en ligne: 28 Jun 2021
Pages: 143 - 154

Résumé

Abstract

The goal of this study was to compare the chemical properties of three muscle types of beef cattle fed using different finishing diets compositions. Four finishing feeding models for bulls based on different proportions of concentrates, maise silage, grass silage and hay were evaluated. Muscles chemical composition was evaluated in m. infraspinatus (ISB), m. longissimus thoracis (LTC) and m. longissimus lumborum (LLS). The chemical composition of meat was influenced by muscle type. ISB was characterised by higher moisture, collagen content, lower protein and ash content, and net energy concentration than LTC and LLS. The differences between diets in dry matter and fat content in each of the muscle groups studied were stated. Furthermore, a difference in the collagen content in LLS and protein content in ISB was noted. High correlations (P ≤ 0.05) were found between the concentrate content in the finishing diet and protein content (r = 0.59) in ISB, and dry matter both in LLS (r = 0.69) and LTC (r = 0.58). The lowest fat content of beef was noted for all muscles obtained from animals fed with a diet composed of grass silage, hay, and concentrates (D1).

Mots clés

  • moisture
  • protein
  • collagen
  • fat
  • ash
access type Accès libre

Effect on Phytochemical Content and Microbial Contamination of Actinidia Fruit after Shock Cooling and Storage

Publié en ligne: 28 Jun 2021
Pages: 155 - 166

Résumé

Abstract

Mini kiwi fruits are tasty and contain valuable nutrients - vitamin, micro end macroelements and polyphenols. The tested cultivars (Sientiabrskaja, Geneva, Issai, Ken’s Red) belong to two species of Actinidia (A. arguta and A. kolomikta), which tolerate well the conditions of a temperate climate with negative temperatures in winter. The effect of postharvest shock cooling on fruit quality was investigated after 6 weeks of storage in CA and then after 5 days of shelf life. Shock cooling of fruit after harvest reduced adverse changes in fruit quality after storage in CA cold storage and shelf life. They were firmer, more puncture resistant, and retained more L-ascorbic acid and polyphenols. After 6 weeks of cold storage in CA, eight types of fungi and molds were found that caused the mycotoxins patulin, deoxynivalenol, and zearalenone were found in the fruit of all cultivars. Fruits of the Ken’s Red cultivar were the most firm and puncture resistant, the darkest, and contained the most anthocyanins and the least L-ascorbic acid. In contrast, fruits of the cultivar Sientaibrskaja were the least suitable for storage and transport.

Mots clés

  • colour
  • firmness
  • polyphenols
  • CA storage
  • shelf life
15 Articles
access type Accès libre

Essential Oil of Cymbopogon Citratus Grown in Umuahia: A Viable Candidate for Anti-Inflammatory and Antioxidant Therapy

Publié en ligne: 28 Jun 2021
Pages: 1 - 14

Résumé

Abstract

The essential oils of Cymbopogon citratus (EOCC) has found use in medicine, food and chemical industry. This study attempts to provide evidence of its suitability for antioxidant and anti-inflammatory therapy. Total phenol and total flavonoid of EOCC was 49.83±0.39mg GAE/g of extract and 352.82±3.45 µg QEC/g of extract respectively. Gas chromatography-mass spectrometry (GC-MS) analysis of its essential oil (EOCC) showed 25 peaks with myrcenyl acetate (9.703%), caryophyllene (8.997%), citronella (6.383%) been the most abundant. The in vitro anti-inflammatory assay using human red blood cell (HRBC) membrane stabilization shows that at 200µg/mL, the percentage inhibition of EOCC was significantly higher compared to diclofenac both for heat-induced and hypotonic induced haemolysis. 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays showed a comparable and dose-dependent increase from 50 to 400 μg/mL in relation to vitamin C. Half maximal inhibitory concentration (IC50) of EOCC (73.16±12.89 μg/mL and 656.01±0.01 μmol Fe (II)/L) was remarkably higher compared to that of vitamin C (69.09±4.52 μg/mL and 246.79±0.01 μmol Fe (II)/L) both for DPPH and FRAP assays respectively. In conclusion, results from this study establish preliminary evidence on the therapeutic potential of EOCC in managing inflammation and oxidative stress caused by free radicals.

Mots clés

  • Antioxidant
  • Anti-inflammatory
  • Essential oils
  • Cymbopogon
access type Accès libre

A Comparative Analysis of Different Varietal of Fresh and Dried Figs by In Vitro Bioaccessibility of Phenolic Compounds and Antioxidant Activities

Publié en ligne: 26 Jun 2021
Pages: 15 - 30

Résumé

Abstract

Varietal and sun-drying effects on phenolic compounds and their antioxidant activity were investigated during the in vitro gastrointestinal digestion of fresh and dried figs. The total phenolic compounds (phenolic, flavonoids, and proanthocyanidin) and their antioxidant activity (ferric reducing power; free radical scavenging activity DPPH, and phosphomolybdenum test) were evaluated before and after digestion. The total phenolic compounds and the antioxidant capacities of fresh and dried figs obtained before digestion were significantly (p < 0.05) higher than those obtained after digestion. A significant decrease (p < 0.05) of phenolic compounds and their antioxidant activity was observed during different digestion phases (oral phase > gastric phase > intestinal phase). A positive correlation was found between the total phenolic compounds and the antioxidant activity tested for both fresh and dried figs. Furthermore, the results showed that the digestion has no effect on the total phenolic compounds; however, a negative influence of the pH and the enzymes was observed on these compounds and their antioxidant activity. During in vitro gastrointestinal digestion, the varietal and the sun-drying has no significant effect on the phenolic compounds and their antioxidant activity. Likewise, the fresh or dry variety kept a high content before and after the digestion.

Mots clés

  • gastrointestinal digestion
  • figs
  • phenolic compounds
  • antioxidant activity
  • varietal effect
  • sun-drying effect
access type Accès libre

Effect of Thermal and Non-Thermal Processing on the Nutritional Composition, Pasting Profile and Protein Secondary Structure of Alfalfa

Publié en ligne: 28 Jun 2021
Pages: 31 - 42

Résumé

Abstract

Alfalfa is an unconventional alternative legume and its potentiality for utilization can be improved by processing. In this study, alfalfa seeds were processed by different thermal and non-thermal techniques and evaluated for their physical properties, colour characteristics, nutritional composition, pasting profile and protein secondary structure. The results were analyzed using Principal Component Analysis to elucidate the effect of processing. Colour of the flour was more affected by thermal processing in comparison to non-thermal processing. Nutritional composition of alfalfa flour was significantly affected by germination as compared to other methods and germinated flour showed an increase in the protein content. All the processing treatments resulted in improving the pasting properties except for germination. Particularly, marked improvement in the pasting properties was observed by wet heat processing and soaking. ATR-FTIR exhibited change in the secondary structure of the protein as a result of processing and showed the dominance of intermolecular β-sheets in extrusion, germination and microwave treated flour and formation of anti-parallel β-sheets after dry heat processing. Wet heat processing and soaking treatment can be employed for alfalfa for enhancing its techno-functionality.

Mots clés

  • alfalfa
  • ATR-FTIR
  • pasting
  • processing
access type Accès libre

Effect of Brachystegia Eurycoma Flour Addition on the Physicochemical Properties of Whole Millet Flour and the Sensory Attributes of its Gluten-Free Bread

Publié en ligne: 28 Jun 2021
Pages: 43 - 52

Résumé

Abstract

This study evaluated the effect of addition of Brachystegia eurycoma flour (BEF), a natural source of hydrocolloids, on the physicochemical properties of whole millet flour (WMF) and the sensory attributes of its gluten-free bread. BEF and sodium carboxylmethyl cellulose (a reference hydrocolloid) were added to WMF at 1.5 and 3% proportions, and breads were baked from the blends. Wheat flour (100%CWF) bread served as the control. Amylose level decreased significantly (p < 0.05), while water absorption capacity, peak and final viscosities of the blends increased with increasing proportion of BEF. The 100%CWF bread had better sensory qualities than WMF-BEF breads. Hence, BEF improved the physicochemical properties of WMF-BEF blend, but did not alter the sensory qualities of its gluten-free bread.

Mots clés

  • Whole millet flour
  • Gluten-free bread
  • Celiac disease
  • Sensory qualities
access type Accès libre

Evaluation of Flours from Ancient Varieties of Wheat (Einkorn, Emmer, Spelt) used in Production of Bread

Publié en ligne: 28 Jun 2021
Pages: 53 - 66

Résumé

Abstract

The study investigates rheological properties of dough and baking process made from flour obtained by milling grains from ancient varieties of wheat (einkorn, emmer and spelt), compared to common wheat flour dough (Arkadia variety). The findings show that einkorn flour dough and emmer flour dough present poor tolerance to mechanical processing and prolonged fermentation. These types of dough should be mixed through relatively short, and fermentation time should not exceed 80 minutes for einkorn dough and 45 minutes in the case of emmer dough. In the case of spelt flour dough, the optimum duration of mechanical processing and fermentation amounted to 10 minutes and 60 minutes, respectively. In terms of technological and baking parameters, spelt flour was most similar to the flour obtained by milling conventional wheat, and the superiority of the former was in fact identified in the case of selected factors. A one-stage method was used in the baking process and the bread was then subjected to organoleptic and physicochemical assessments and to texture profile analysis (TPA). Measurements were also performed to determine the indicators reflecting the quality of the baking processes, including dough yield, baking loss and bread yield. The physical parameters of the bread produced were significantly related to the wheat variety. The loaves made from einkorn and spelt flour were of good quality, comparable to the bread made from the conventional wheat, while their baking quality indicators were satisfying. Bread dough made from emmer flour did not meet the required parameters mainly related to the organoleptic assessment and selected physical properties of the bread crumb. However, the one-stage production method should not be applied to doughs made from emmer flour. Given the specific characteristics of the breads produced from the ancient wheat varieties, including their pleasant taste and aroma, as well as attractive colour in the case of einkorn bread, these baked products may be an interesting addition to the assortment of breads on offer from bakeries, restaurants and agritourist farms.

Mots clés

  • einkorn
  • emmer
  • spelt
  • dough rheology bread baking
  • physicochemical properties of bread
  • TPA
access type Accès libre

Bioactive, Antioxidant and Antidiabetic Properties of Cooked and Uncooked Irish Potato (Solanum Tuberosum)

Publié en ligne: 28 Jun 2021
Pages: 67 - 73

Résumé

Abstract

Potatoes are considered very important staple and antioxidant-rich tubers in human diet. The present study evaluated the bioactive, antioxidant, antidiabetic and inhibition of lipid peroxidation properties of cooked and uncooked Irish potatoes. The samples were subjected to total phenolic (TPC), total antioxidant capacity (TAC), total flavonoids (TFC), ascorbic acid (AsA) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity analyses using spectrophotometric method. Also Fe2+-induced lipid peroxidation, α-glucosidase and α-amylase inhibition were assayed. The results revealed that there is no significant (p < 0.05) difference in TPC and TAC of the potatoes samples but there was a significant (p < 0.05) enhancement in TFC and reduction in AsA of the cooked potatoes. There is also dose-dependent inhibition in DPPH and α-glucosidase and α-amylase enzymes. The IC50 revealed that cooked sample has significant higher (p < 0.05) inhibition in the enzymes assay. The lipid peroxidation was also reduced upon incubation with Irish potato samples but higher inhibition was exhibited by the cooked potato. In conclusion, this study has shown that Irish potato can be a good functional food in the management of diseases.

Mots clés

  • Phenolics
  • Flavonoid
  • α-glucosidase
  • α-amylase
  • Lipid peroxidation
access type Accès libre

Evaluation of Crystalline Cellulose of Corn Straw through Different Pretreatments Via X-Ray Diffraction, Scanning Electron Microscopy and Infrared Spectroscopy

Publié en ligne: 28 Jun 2021
Pages: 74 - 82

Résumé

Abstract

Waste recycling is beneficial not only for the environment but also for the economy and the society at large. Corn stalks, the most abundant crop waste, are processed with oven drying, steaming, complex enzymatic hydrolysis (cellulase, xylanase, β-glucanase and pectinase), and fermentation (by Candida utilis and Pachysolen tannophilus), were analyzed via X-ray diffraction, Scanning Electron Microscopy (SEM) and Infrared Spectroscopy (IR). The results indicated that thermophilic digestion destroyed glycosidic bonds and fibrous crystal have a significant effect on the degradation of the corn stalks, while complex enzyme hydrolysis only slightly degraded fibrous crystal. Fermentation did not significantly reduce fibrous crystal. Therefore, our research suggested that thermophilic digestion is the appropriate way to increase the saccharification rate and feed yield of corn stalks.

Mots clés

  • Corn stalk
  • X-ray diffraction
  • Fibrous crystal
  • SEM and IR
access type Accès libre

Ethanolic Extracts from Agro-Industrial Co-Products Enhance Oxidative Stability of Candelilla Wax or Celluloses Derivatives Oleogels

Publié en ligne: 28 Jun 2021
Pages: 83 - 92

Résumé

Abstract

Ethanol oleoresins obtained from orange peel, pea pod, or pomegranate peel were employed to enrich soybean oil before elaborating two types of oleogels, one made with candelilla wax, another made with a mixture of celluloses derivatives, in order to determine their effect on oleogel oxidative stability. Orange peel oleoresin obtained a higher amount of polyphenols as catechol acid equivalent (9.09 meq/g), as compared to pea pod oleoresin or pomegranate peel (8.80 and 8.55, respectively), although pomegranate peel presented the higher TEAC (1.67, twice than the other samples). Oleogels elaborated with celluloses were presented better oxidative stability (oxidative rancidity and peroxide index) as compared to samples elaborated with candelilla wax, since waxes minor constituents employed as oleogelators could promote prooxidant activity. Samples with pomegranate oleoresin presented enhanced oxidative stability. Candelilla wax has a more marked effect on the oleogels thermal properties of due to their influence on fatty acids crystallization, because in celluloses oleogels the mechanism of gelation does not imply the formation of a highly ordered secondary structure. This finding opens the possibility to, on one hand, use oleoresins to enhance the oxidative stability of oleogels; and on the other hand, to select the oleogelator, waxes, or celluloses, based on thermal properties and other aspects, depending on the further application of oleogel thinking in oleogel thermoreversible capacity.

Mots clés

  • Oleogel
  • candelilla wax
  • celluloses
  • oxidative stability
  • agro-industrial co-product
access type Accès libre

Preparation of Vitamin K2 Mk-7 in a Process of Fermentation of Different Seeds and Cereals by Bacteria Bacillus Subtilis

Publié en ligne: 28 Jun 2021
Pages: 93 - 104

Résumé

Abstract

In this study, 10 different plant materials (seeds/beans) were fermented by Bacillus subtilis var. natto. The influence of the process on vitamin K2 MK-7 content during different fermentation periods was assessed. Fermented plant samples were analyzed by the procedure using HPLC UV/DAD. The fermented sunflower seeds, mung beans and peas appeared to be the most promising plants, reaching values of K2 of 1080.18±55.11 µg/100g, 806.45±60.95 µg/100g and 636.92±59.86 µg/100g, respectively. The experiments showed that extending of the fermentation time to 5–6 days was favorable for the menaquinone-7 yield. The results show that almost all fermented seeds/beans, apart from soybean, can be good source of vitamin K2 MK-7 and represent a new perspective, especially in terms of lower the phytoestrogen content.

Mots clés

  • (natto)
  • bacterial fermentation
  • seeds/beans
  • HPLC/UV-DAD
  • menaquinone-7
  • vitamin K2 MK-7
access type Accès libre

Effect of Complexation Conditions on Microcapsulation of Lactobacillus Casei L61 in Gellan Gum–Chitosan Gels

Publié en ligne: 28 Jun 2021
Pages: 105 - 114

Résumé

Abstract

Probiotics have many benefits for human intestinal health. However, Probiotics have poor tolerance to gastric acid and bile salts of the stomach. Microencapsulation could confer protection to probiotic against harsh environments effectively. In this experiment, Lactobacillus casei L61 was embedded by extrusion with gellan gum and chitosan as wall material. The viable cells and encapsulation yield of microcapsules were used as the indexes, the optimum values of each factor were determined by a single factor experiment. Chitosan concentration 0.50%, chitosan pH 4.5, gellan gum concentration 1.50%, the volume ratio of bacterial suspension to gellan gum is 1:6, the volume ratio of bacterial gum to chitosan is 1:4, the stirring time is 40min.

Mots clés

  • Probiotics
  • Microencapsulation
  • L61
  • gellan gum
  • Chitosan
access type Accès libre

Effect of Alcalase on Antioxidant and Antihypertensive activities of Goat Milk Fermented by Lactobacillus Plantarum L60 and Lactobacillus Rhamnosus LR22

Publié en ligne: 28 Jun 2021
Pages: 115 - 122

Résumé

Abstract

Effect of alcalase addition, inoculum size, bacterial ratio, fermentation time and temperature on antioxidant and antihypertensive activities of goat milk fermented by Lactobacillus plantarum L60 and Lactobacillus rhamnosus LR22 was studied by using DPPH free radical scavenging rate, ACE inhibition rate, pH, and titer acidity as responses through single factor experiments. The results showed that the optimal alcalase addition, inoculum size, bacterial ratio, fermentation time and temperature was 0.15%, 5%, 1:1, 12h and 37°C, respectively, the probiotic goat milk prepared under these conditions had high antioxidant and antihypertensive activities.

Mots clés

  • goat milk
  • Alcalase
  • Lactobacillus plantarum Lactobacillus rhamnosus
  • antioxidant
  • ACE inhibition
access type Accès libre

Possibility of Reinforcement the Functional Potential of Vegetable Juices with the use of Novel Strain Lactiplantibacillus Plantarum EK11 Isolated from an Unconventional Fermented Food Matrix

Publié en ligne: 28 Jun 2021
Pages: 123 - 134

Résumé

Abstract

The study investigated the suitability of a novel strain Lactiplantibacillus plantarum EK11 for obtaining fermented tomato and beetroot juices with improved functional potential. EK11 had the capability of dynamic acidification of pasteurized vegetable beverages. The lowest values of pH were noted in juices after 48 h of fermentation with the probiotic L. plantarum 299v (pH=3.72±0.01 in beet juice and pH=3.43±.0.01 in tomato juice). The fermentation increased the lycopene content in tomato juices from 27.90±0.31µg mL−1 (after 24-h fermentation by strain EK11) to 116.86 ±0.19 µg mL−1 (final products obtained using strain 299v after 7-day cold storage). The process contributed to changes in the betanin and vulgaxanthin-I concentration in beetroot beverages. All fermented products exhibited antioxidative activity, i.e. 50% inhibition of 1,1-diphenyl-2-picrylhydrazyl free radicals. Moreover, three genes involved in the biosynthesis of bacteriocins were detected in the novel strain EK11, which exhibits functional and technological potential for the production of fermented foods.

Mots clés

  • lactic acid fermentation
  • bacteriocins
  • functional food
access type Accès libre

Optimization of Fermentation Conditions for Cell Envelope Proteinase Produced by Lactobacillus Plantarum LP69

Publié en ligne: 28 Jun 2021
Pages: 135 - 142

Résumé

Abstract

Cell-envelope proteinases (CEPs) can hydrolyze casein into functional peptides, which is beneficial to the health of the host. The single factor experiment screened out that the optimal conditions for CEP production by Lactobacillus plantarum LP69 were 37°C, 20h, initial pH of 7, and optimal inoculation amount of 5%. The best conditions for this experiment were obtained by orthogonal experiment: time 22h, temperature 39°C, initial pH value of 6, and inoculation amount of 5%. Under this culture condition, the target protease activity of Lactobacillus plantarum LP69 reached 22.31±0.82U/mL, the protein content was 19.07±0.36mg/mL, and the specific activity was 1.17±0.06U/mg. The specific activity significantly increased by 15.8% compared with the control (p<0.05).

Mots clés

  • cell-envelope proteinases
  • fermentation optimization
  • Orthogonal experiment
access type Accès libre

Chemical Characteristics of Limousine Beef Depending on Finishing Diets and Muscle Type of Meat

Publié en ligne: 28 Jun 2021
Pages: 143 - 154

Résumé

Abstract

The goal of this study was to compare the chemical properties of three muscle types of beef cattle fed using different finishing diets compositions. Four finishing feeding models for bulls based on different proportions of concentrates, maise silage, grass silage and hay were evaluated. Muscles chemical composition was evaluated in m. infraspinatus (ISB), m. longissimus thoracis (LTC) and m. longissimus lumborum (LLS). The chemical composition of meat was influenced by muscle type. ISB was characterised by higher moisture, collagen content, lower protein and ash content, and net energy concentration than LTC and LLS. The differences between diets in dry matter and fat content in each of the muscle groups studied were stated. Furthermore, a difference in the collagen content in LLS and protein content in ISB was noted. High correlations (P ≤ 0.05) were found between the concentrate content in the finishing diet and protein content (r = 0.59) in ISB, and dry matter both in LLS (r = 0.69) and LTC (r = 0.58). The lowest fat content of beef was noted for all muscles obtained from animals fed with a diet composed of grass silage, hay, and concentrates (D1).

Mots clés

  • moisture
  • protein
  • collagen
  • fat
  • ash
access type Accès libre

Effect on Phytochemical Content and Microbial Contamination of Actinidia Fruit after Shock Cooling and Storage

Publié en ligne: 28 Jun 2021
Pages: 155 - 166

Résumé

Abstract

Mini kiwi fruits are tasty and contain valuable nutrients - vitamin, micro end macroelements and polyphenols. The tested cultivars (Sientiabrskaja, Geneva, Issai, Ken’s Red) belong to two species of Actinidia (A. arguta and A. kolomikta), which tolerate well the conditions of a temperate climate with negative temperatures in winter. The effect of postharvest shock cooling on fruit quality was investigated after 6 weeks of storage in CA and then after 5 days of shelf life. Shock cooling of fruit after harvest reduced adverse changes in fruit quality after storage in CA cold storage and shelf life. They were firmer, more puncture resistant, and retained more L-ascorbic acid and polyphenols. After 6 weeks of cold storage in CA, eight types of fungi and molds were found that caused the mycotoxins patulin, deoxynivalenol, and zearalenone were found in the fruit of all cultivars. Fruits of the Ken’s Red cultivar were the most firm and puncture resistant, the darkest, and contained the most anthocyanins and the least L-ascorbic acid. In contrast, fruits of the cultivar Sientaibrskaja were the least suitable for storage and transport.

Mots clés

  • colour
  • firmness
  • polyphenols
  • CA storage
  • shelf life

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