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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
18.04.2020.
Original scientific paper
Chemical constituents in leaves and aroma products of Nicotiana rustica L. tobacco
Nicotiana rustica L. (Aztec tobacco) is the only Nicotiana species, except common tobacco (N. tabacum L.), which is cultivated for tabacco products. The leaves of N. rustica, however, accumulate various specialized metabolites of potential interest. Therefore, the objective of this study was to evaluate certain classes of metabolites (by HPLC and GC-MS) in the leaves, the essential oil (EO), concrete and resinoid of N. rustica. Three pentacyclic triterpenes were identified in the leaves (by HPLC): betulin (252.78 µg g-1), betulinic (182.53 µg g-1) and oleanolic (69.44 µg g-1) acids. The dominant free phenolic acids in the leaves (by HPLC) were rosmarinic (4257.38 µg g-1) and chlorogenic (1714.40 µg g-1), and conjugated forms of vanillic (3445.71 µg g-1), sinapic (1963.11 µg g-1), and syringic (1784.96 µg g-1). The major flavonoids in the leaves were luteolin (960.44 µg g-1), apigenin (880.66 µg g-1) and hyperosid (780.72 µg g-1). The GS-MS profiling of the EO identified 19 components and the major ones were phytol (43.68 %), solanone (5.54 %), cis-5-butyl-4-methyldihydrofuran-2(3H)-one (5.23 %), dihydro-β-ionone (4.25 %), α-ionene (3.54 %),and β-damascenone (3.03 %). The major volatiles in the concrete were isoamyl alcohol (28.82 %), oxynicotine (9.02 %), phytol (7.80 %), 4-mеthyl-1-penthanol (6.33 %), cotinine (5.55 %) and 3-metyl-3-penthanol (4.09 %). Resinoid composition was dominant by nicotine (39.75 %), phytol (11.23 %), eicosane (4.88 %), diethyl phthalate (4.19 %), dibutyl phthalate (3.48 %) and solanone (3.27 %). Concrete and resinoid showed weak antibacterial activity . These results create grounds for considering N. rustica as a source to obtain aroma or other bioproducts.
Venelina Popova, Tanya A. Ivanova, Albena S. Stoyanova, Violeta V. Nikolova, Margarita H. Docheva, Tzveta H. Hristeva, Stanka T. Damyanova, Nikolay P. Nikolov
18.10.2020.
Original scientific paper
Assessment and Evaluation of Student Learning Through a Project-Based Assignment on Note by Note Cooking
Many innovative teaching and learning methods are used in higher level education including project-based learning (PBL). Since 2012 a PBL assignment project has been undertaken by master students of the Advanced Molecular Gastronomy module at Technological University Dublin (TU Dublin). The aim is to stimulate student learning and creativity by using Note by Note cooking in a PBL assignment while at the same time complying with the requirements of the annual International Note by Note contest which is held in Paris, France. Direct and indirect assessment methods were used to assign individual grades and to gather student feedback about the module. The direct methods were both formative and summative. The indirect method used was a student feedback questionnaire. Results to date (2012-2019) showed that 92% of learners successfully passed the module. However, further evaluation of individual assessment results revealed that most students achieved higher scores for finding and using resources, asking further questions and developing their own answers than for analysing, synthesising and evaluating information (P≤0.01). Overall students were happy with the module content and said that they learnt about Note by Note cooking, chemical compounds, researching, independent-thinking and perseverance. In future students should carry out a more in-depth analysis, synthesis and evaluation of information.
Róisín M. Burke, Pauline Danaher
18.04.2020.
Original scientific paper
Zizyphus lotus (L.) extracts as prebiotics in the aggregation and adhesion of probiotic and inhibition of pathologic bacteria from patients with colorectal cancer
The mucosal surfaces of the intestinal tract harbor a complex microbiota. Bacteria enter in contact with intestinal cells and bestow important nutritional, metabolic and protective functions which benefit the host. Various factors are able to alter the balances between different intestinal bacteria. Dysbiosis has been described in various pathologies and metabolic diseases in humans, such as cancer. Colorectal cancer pathology can benefit from gut microbial imbalance. Its overgrowth may lead to acute symptoms. An alternative strategy to restore this balance is the use of plant extracts which exhibit a prebiotic activity by stimulating of probiotic bacteria and antimicrobial activity against pathogenic bacteria colonization. The present study aims to evaluate the in vitro antioxidant and antibacterial activity of phenolic extracts (Aqueous extract "AE" and Methanolic extract "ME" ) from Zizyphus lotus. It aims also to investigate the effect of this extract as a prebiotic on the aggregation of probiotic and inhibitory effects of pathogenic bacteria isolated from faeces of patients with colorectal cancer. Phytochemical analysis of different extracts from Zizyphus lotus by HPLC showed that all are rich in phenolic compounds (225.40 mgAGE/gDW for AE and 63.04 mgAGE/gDW for ME extracts). Moreover, all extracts showed an important antioxidant activity (227 µg/ml for AE and 195 µg/ml for ME). These extracts also exhibited a significant prebiotic effect and antibacterial activity. Characterization of the in vitro effect of the aqueous extract showed that the percentage of autoaggregation and adhesion of probiotic and inhibitory effects of pathogenic bacteria increased in the presence of aqueous extracts.
Sara Ouldchikh, Aicha TirTouil, Boumédiene Meddah
18.04.2020.
Original scientific paper
Mango peel ingredient as salt and phosphate replacement in chicken breast marinade
Whole mango peel powder and fibre extracted from mango peel were investigated as potential ingredients to replace salt and phosphate in chicken marinade. Whole mango peel powder possessed higher water absorption capacity than mango peel fibre, 4.57% and 1.47%, respectively (P < 0.05). Similar oil absorption capacity was observed in both mango peel ingredients (P > 0.05). Purified pectin and sorbitol syrup were also used to compare the water holding capacity in marinated chicken breasts. Mango peel ingredients exhibited less cooking loss than pectin and sorbitol syrup, however, higher cooking loss than sodium tripolyphosphate (STPP) and NaCl (P > 0.05). Marinating with mango peel ingredients significantly increased a* value of chicken breasts after cooking, while L* and b* values were similar in marinating with NaCl (P > 0.05). Hardness of frozen fully cooked chicken breast was measured after thawing. The lowest shear force of 7.13 N was observed in chicken breasts marinated with mango peel fibre (P < 0.05), while the hardness of chicken breasts marinated with whole mango peel powder was not significant different from STPP and NaCl treatments. Results from this study revealed a potential approach of utilizing fruit waste as an ingredient to substitute phosphate and salt in chicken marinade.
Sunisa Roidoung, Napatsawan Ponta, Ruttapong Intisan
18.04.2020.
Original scientific paper
Evaluation of growth and cereulide production by Bacillus cereus isolated from cooked rice
Conditions influencing Bacillus cereus growth and cereulide production, such as temperature and pH, were evaluated at varying incubation periods. The growth and cereulide production at different temperatures and pH values ranging from 10 to 40 ºC and 5.0 to 8.5, respectively showed that the temperature from 20 to 30 ºC and at pH from 6.0 to 7.0 gave the optimum growth and cereulide production by B. cereus SA105. pH below 6.0 resulted in reduced growth and cereulide production. Cereulide production increased along with the incubation period, and maximum cereulide titre (ng/mL) of 1219.1±8.90 was obtained after 6 days of incubation at 30 ºC and pH 6.5 under static conditions. There was no quantifiable toxin at incubation temperatures of 10 and 40 ºC by B. cereus SA105. This work further reveals that B. cereus growth and cereulide production was significantly affected by temperature and pH in relation to the incubation period. Furthermore, the findings of this study will serve as a means for reducing the diversity of emetic toxin-producing B. cereus population in food and food products, thus preventing food poisoning.
Damilola Seyi-Amole, Abiodun A. Onilude, Dasari S. Rani, Prakash M. Halami
18.04.2020.
Original scientific paper
Effect of olive pulp enrichment on physicochemical and antioxidant properties of wheat bread
Black and green olive pulp was added to wheat bread formulation at different levels (5, 10, 15%) with the aim to improve its nutritional value by enhancing the phenolic content and antioxidant capacity. Additionally, the effects of the fortification with olive pulp on the physical characteristics, staling rate and overall consumer acceptability of the formulated breads were explored. Both olive pulps exhibited significantly higher antioxidant activity than refined wheat flour. Baking imparted an impressive increase in TPC, TFC and antioxidant activity of breads as revealed by comparison of experimental with theoretical values but returned significant differences only in the case of TPC when a two-tailed t-test for paired data was applied. Texture measurements showed a substantial increase in hardness with storage along with decreasing loaf volume and increased density. Hydroxytyrosol was the major phenolic compound of fortified breads followed by tyrosol. Olive pulp could be incorporated in a bread formulation without interfering with the general sensory acceptability.
Anna Marinopoulou, Maria Papageorgiou, Maria Irakli, Dimitrios Gerasopoulos
01.12.2018.
Professional paper
Effects of “starch:water” ratio on gelatinization of pinhão starch from nine germplasm collections, measured by Differential Scanning Calorimetry
Camila D. Bet, Rossane C. B. Godoy, Layse P. Cordoba, Ivo M. Demiate, Luiz G. Lacerda, Egon Schnitzler
01.12.2018.
Professional paper
Development and incorporation of nanoemulsions in food
Antonio de Jesus Cenobio-Galindo, Rafael G. Campos-Montiel, Rubén Jiménez-Alvarado, Isaac Almaraz-Buendía, Gabriela Medina-Pérez, Fabián Fernández-Luqueño
01.12.2018.
Professional paper
Effect of osmotic drying on physicochemical properties of pansies (viola × wittrockiana)
Luana Fernandes, Susana Casal, Agostinho Magalhães, Paula Baptista, José A. Pereira, Jorge A. Saraiva, Elsa Ramalhosa
18.10.2019.
Original scientific paper
Consumer awareness of the use of food labels in Lagos state, Nigeria
The increase in relative level of education and the growing middle-class income earners in Nigeria have made packaged food items attractive to consumers. These foods provide handy, nutritious and convenient food for consumers; however, they also come with public health concerns. From a policy perspective, food labelling can gauge consumers’ response to the safety conditions of packaged food. However, understanding consumers’ awareness and the use of food label information has attracted little research attention in many developing countries in sub-Saharan Africa. In this study, we investigated consumers’ awareness of the use of food safety labels in Lagos state, Nigeria. We used primary data collected using pretested structured questionnaire from 220 food shoppers who bought pre-packaged foods. A two-stage sampling technique was used to select the respondents. Consumers’ awareness and use of food safety information was revealed using descriptive statistics; Ordinal Regression Analysis was used to examine the socioeconomic factors determining the frequency of reading food safety labels. We found evidence of the influence of socioeconomic characteristics on how consumers read food labels. The study therefore recommends that there should be continuous awareness campaigns on the importance of food labels in ensuring safety and food producers should make sure their food labels are legible.
Samuel Danilola, Olubunmi A. Omotesho, Jubril Animashaun