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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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18.04.2017.

Original scientific paper

A methodological approach for optimum preservation results: The packaging paradigm

The food preservation hypothesis as impacted by overall packaging applications is considered in this work. The objective was to devise a decision supportive method for the selection of “just-right” packaging materials, techniques and procedures. For that, food preservation was critically approached in order to identify the optimum outcome at experimental and packaging selection decision-making levels. A mathematically supported and proven knowledge classification, and the establishment of a straightforward coherence mode among the principles of the natural systemic phenomena, were used. The ultimate aim of this work was to justifiably surpass a simple description of packaging according to its measurable specifications, and instead, engage its inherent properties into a cyclic 8-steps-process for eventually understanding its potential to support any particular preservation hypothesis in question. The proposed methodology includes primarily, the consideration of the study hypothesis and, in parallel, the conclusive remarks and claims with respect to the experimental factors involved (properties, parameters, relations and conditions). Considering the experimentally controlled set-ups that a researcher has to expose the food system to and the role of packaging in obtaining its preservation potential, our method supports the experimenters in selecting the experimental conditions under which the preservation hypothesis can be disclaimed and furthermore, it could indicate the way to reduce experimentation research waste.

ANTONIOS KANAVOURAS, Frank A. Coutelieris

18.10.2017.

Original scientific paper

Impact of selected polyphenolics on the structural properties of model lipid membranes – a review

This review is a presentation of data gathered on the interactions of several polyphenolics (i.e., phenolic acids, stilbenes, flavonoids) with lipid bilayers of different lipid compositions. These polyphenolics have been investigated through a combination of fluorescence spectroscopy, electron paramagnetic resonance spectroscopy, and differential scanning calorimetry, to detect changes in membrane fluidity. Among the investigated phenolic acids, the least polar phenolic acid, p-coumaric acid, has the greatest effect on lipid membrane structure. It appears to have a greater ability to cross membranes by passive transport than more polar phenolic acids. On the other hand, among the flavonoids that have been studied, the anthocyanins cyanidin-3-glucoside and its aglycone are inactive. All of the flavonols tested, except for epigallocatechin-3-gallate, promote small decreases in membrane fluidity. Computer simulation of electron paramagnetic resonance spectra for flavonoids indicated two or three regions in the phosphatidylcholine/ phosphatidylserine (2.4:1) membrane with different fluidity characteristics. The effects of the different flavonoids are correlated to their structural characteristics, whereby even the difference in one -OH group can be important, as can the number of H-bonds they form. The role of membrane composition and flavonoid structure in these interactions with lipid membranes are of great importance for bioavailability of these compounds and for their biological effects in an organism.

Natasa Poklar Ulrih, Ajda Ota, Veronika Abram

18.10.2017.

Original scientific paper

Food science and technology students self-evaluate soft and technical skills

Food Scientists and Technologists (FS&T) need diverse skills in the globalized food and drink sector: Food-specific or scientific / technical skills and generic or intuitive soft skills. This study determined how satisfied FS&T students were with overall improvement, and in key technical and soft skills, based on their university work; and if satisfaction was linked to geography, degree in progress, anticipated degree, anticipated work place or anticipated job responsibility. An on-line survey was completed by 267 students in over 20 countries using a 5-point Likert scale to evaluate satisfaction. Responses were analyzed by the Friedman or Kruskal Wallis tests for more than two groups, otherwise by the Wilcoxon Signed Rank or Mann-Whitney tests. There were no differences in Overall Satisfaction with technical and soft skills training. Among soft skills, training in Working with Others and Being Responsible were more often rated “Excellent” and students were more satisfied with their training than with Solving Problems, Communication and Positive Attitude. Students anticipating a job with high responsibility were more satisfied with overall soft skill training and with 3 of the 5 specific soft skills. Among technical skills, students were more satisfied with improvement in basic sciences (Microbiology, Chemistry, Processing, Safety), and those in Northern Europe were more satisfied with overall technical training. These data show variations in perception and/or efficacy of technical and soft skill training in Food Science programmes and underline the need for separate attention to the incorporation of soft skill training into the design of FS&T courses.

Katherine M. Flynn, Peter Ho, Margarida C. Vieira, Paola Pittia, Marco Dalla Rosa

18.10.2017.

Original scientific paper

Effect of tuna skin gelatin-based coating enriched with seaweed extracts on the quality of tuna fillets during storage at 4 °C

Nowadays, consumers demand high quality food products with an extended shelf-life without chemical additives. Edible coatings (EC) containing natural compounds are a promising preservation technology for raw seafood without compromising fresh-like appeal and nutritional content. The aim of this work was to evaluate the effect of Thunnus obesus skin gelatin-based EC containing Codium spp. or Fucus vesiculosus extracts on raw tuna preservation. Three gelatin-based EC (gelatin (5 %) + glycerol (25 %); gelatin (5 %) + Codium spp. (1 %) + glycerol (25 %); gelatin (5 %) + Fucus vesiculosus (1 %) + glycerol (25 %)) were applied directly on the surface of tuna fillets. Functional properties of gelatin and gelatin-based EC containing seaweed extracts were also studied. The gelatin was extracted by an acid-swelling process in the presence/absence of pepsin, followed by subsequent heating/refrigeration, after a pre-treatment with NaOH. The type of acid, temperature and concentration of NaOH greatly influence the process yield. The higher extraction yield was achieved using acetic acid in the presence of pepsin by subsequent refrigeration, especially when skins were previously treated with NaOH (0.2 M). Tuna quality was assessed over 12 days of storage at 4 ± 1 °C in terms of chemical and microbial indices. Results showed that tuna skin gelatin-based EC avoids tuna deterioration. Microbial growth, assessed by total viable counts, and total volatile basic nitrogen were maintained below the maximum limits recommended, contrarily to the control. Additionally, the use of EC increased the stability of red colour during storage.

Milene Vala, Ana Augusto, Andre Horta, Susana Mendes, Maria M. Gil

18.10.2017.

Original scientific paper

Effect of Grewia venusta FRESEN mucilage on the proximate composition, physical and sensory properties of bread produced from wheat and cassava composite flours

Wheat and cassava composite breads are generally associated with volume and textural defects in contrast with the traditional wheat based variants. Efforts to mitigate this challenge through use of synthetic additives have been unsuccessful owing to safety concerns. The objective of this study was to explore Grewia venusta mucilage as a potential natural additive in wheat-cassava composite bread production. Sweet cassava flour was used to replace wheat flour at 100: 0 (control), 90:10, 80:20 and 70:30% ratios in bread making. Aqueous extract of G. venusta stem bark was oven dried (50±3 °C), milled and added at 0, 1.0 and 2.0% (w/w) to the flour mixtures. These, along with other conventional inputs were mixed, and used to produce bread. Proximate compositions, physical and sensory properties of the bread loaves were evaluated. Cassava flour inclusion resulted in significant (P≤0.05) decrease in the protein content of the control from 18.1% to 12.1% (90:10%), 11.5% (80:20%) and 9.9% (70:30%). Addition of mucilage marginally increased the protein and dietary fibre contents of the loaves. Loaves containing 1-2% mucilage were more regular in shape with smoother crust than those without mucilage. Cassava flour addition at 10%, 20% and 30% decreased loaf height from 6.0 cm to 5.8 cm, 5.7 cm and 5.5 cm, as well as loaf volume from 815.5 cm3 to 783.1 cm3 , 776.8 cm3 and 744.5 cm3 , respectively. Mucilage inclusion resulted in increased heights and volumes of the loaves and reduced weights of loaf fragments upon slicing. The mucilage significantly improved the texture of the bread loaves.

Arubi P. Alobo, Gibson L. Arueya

01.12.2016.

Professional paper

Cytotoxic, antioxidant and antimicrobial properties of red sweet pepper (Capsicum annuum L. var. Llanerón) extracts: In vitro study

Alcoholic and aqueous extracts were obtained from red sweet pepper (Capsicum annuum L.) by different methodologies to evaluate their cytotoxic, antioxidant and antimicrobial properties. Alcoholic extracts (MFP, MSd, SFP, SDP, SSd) from fresh red sweet pepper (FP) and dry pulp (DP) and seed (Sd) were obtained by maceration (M) and Soxhlet (S) equipment using methanol as extraction solvent; whereas aqueous extracts (LFP, LSd) were obtained by decoction followed by lyophilization (L). Human tumoral cell lines from breast (MCF-7 and SKBr3), prostate (PC3) and cervix (HeLa), and fibroblasts (as control) were used to determine the cytotoxic properties by the MTT assay. Antioxidant and antimicrobial properties were determined by DPPH and disc diffusion method, respectively. The extracts SDP and SFP showed the higher cytotoxic activity. The SDP extract had a significant (P < 0.05) in-vitro effect on HeLa (1.9 ± 1.4 µg/mL) and PC3 (< 1 µg/mL) cells with a moderated impact on fibroblasts (26.1 ± 1.2 µg/mL); whereas, SFP had a significant (p < 0.05) effect on MCF-7 cell line (2.1 ± 1.2 µg/mL) with a moderated impact on fibroblasts (25.9 ± 1.0 µg/mL). The higher antioxidant activity was found for MFP (80.3 ± 0.2%) and SFP extracts (75.5 ± 0.5%). Mild antimicrobial activity was only observed for alcoholic extracts. The results showed the potential of red sweet pepper (C. annuum L.) as a source of antioxidant and cytotoxic compounds, and suggest the need of further studies to isolate and characterize the bioactive compounds that impart those properties.

Rosa Raybaudi-Massilia, Alírica I. Suárez, Francisco Arvelo, Alexandra Zambrano, Felipe Sojo, María I. Calderón-Gabaldón, Jonathan Mosqueda-Melgar

01.12.2016.

Professional paper

Effect of inulin on dough and biscuit quality produced from different flours

One of the methods of improving the nutritional profile of baked-goods is the incorporation of dietary fibre (DF) to the formulation. However, DF retains more water than wheat flour, which affects dough rheological properties and thus the final product quality. Flour is the main ingredient in biscuits and contributes to the baked texture and shape of biscuits. There are large differences in quality among the flours from wheat cultivars and among non-wheat flours used for biscuit production. In previous works, different dietary fibres were tested and inulin was found to have a positive quality  effect on biscuits made from an all-purpose wheat flour without the need of introducing significant changes in dough properties. To know whether these results are extended to different types of flours that can be used for biscuit production, this paper aimed to analyse the effects of different levels of inulin incorporation on dough and biscuits quality made from three different wheat flours and one triticale flour. Chemical and physic-chemical characterization of the flour samples was performed and compared (moisture, ashes, gluten, solvent retention capacity (SRC) and protein content). Inulin was incorporated to biscuits formulation in two levels: 6 and 12% (wheat replacement). Dough and biscuits quality was measured by spread rate during baking and biscuit factor, texture and surface colour. Inulin incorporation increased dough spreading and biscuit factor and decreased biscuit hardness. The enhancing effect of inulin was observed in all flour. The results confirmed the effect of inulin on biscuits obtained with all flour assayed, despite the differences in flour quality that was tested.

Maria S. Blanco Canalis, Alberto E. León, Pablo D. Ribotta

01.12.2016.

Professional paper

Texture analysis of blanched vegetables using high- and low-speed measuring methods

Quality reductions of raw and cooked vegetables are caused by forces generated during industrial high-speed manufacturing. However, the transferability of low-speed texture measurement methods to high speed processes is limited. Therefore, analyses with a low-speed uniaxial compression test (breaking strength σ, breaking strain ε) and a high-speed pendulum test (relative fracture height Δh) at different speeds (3.6, 4.4, 5.3 m s-1) were carried out. Textural values for potatoes, carrots and celeriacs (0 to 25 min cooking time) were recorded to compare the two measurement methods. Furthermore, whether the increase of textural values of blanched vegetables measured with low-speed methods, was also observable with high-speed methods, was also investigated. Low to medium rank correlation coefficients (rS < 0.659) between parameters of the two methods were calculated. In contrast to σ and ε, Δh-values indicate a distinct initial increase as well as textural maxima between 5.0 to 12.5 min cooking time for all tested potato and carrot varieties. On the other hand, most celeriac samples did not exhibit an increase in texture with respect to cooking time. Therefore, a textural analysis at high speeds is necessary for the prediction of textural characteristics of blanched vegetables during high-speed processing in order to reduce quality degradation.

Christian Schmitt, Thomas Friedl, Nadine Mattes, Uwe Grupa, Oliver Hensel

01.12.2016.

Professional paper

Extrusion cooking technology: Principal mechanism and effect on direct expanded snacks – An overview

The snack industry is one of the fastest growing food sectors and is an important contributor within the global convenience food market. Nowadays snacks and convenience foods are also consumed regularly in India. Properly designed convenience foods can make an important contribution to nutrition in societies where social changes are altering traditional patterns of food preparation. Extrusion cooking as a popular means of preparing snack foods based on cereals and plant protein foodstuff has elicited considerable interest and attention over the past 30 years. Several studies on the extrusion of cereals and pulses, using various proportions, have been conducted because blends of cereals and pulses produce protein enriched products. Special importance is placed on the physicochemical and chemical modifications of protein, starch and dietary fibre. Extruded products can be categorized for a particular application based on their functional properties such as water absorption and water solubility index, expansion ratio, bulk density and viscosity of the dough.Therefore, the literature was reviewed for effect of extrusion processing on product parameters, and nutritional and anti-nutritional properties of extruded products.

Ajita Tiwari, S. K. JHA

01.12.2016.

Professional paper

In vitro investigation of antioxidant activities of Launea taraxacifolia and Crassocephalum rubens

Launea taraxacifolia and Crassocephalum rubens are among many wild, underutilized and under cultivated vegetables in Nigeria that are at risk of extinction. Total flavonoid contents (TFC), total phenolic contents (TPC), and antioxidant activities of different concentrations (1-5 mg ml-1) were evaluated; using in vitro assays to assess the scavenging properties of 2, 2-diphenyl-1-picryl hydrazyl (DPPHRSP), nitric oxide (NORSP) and hydroxyl (OHRSP). Phenolic profiles of the alcoholic extracts were characterized using high-performance liquid chromatography techniques. The results revealed higher TFC (mg/100g RE) in aqueous (6.06± 0.02-78.79±0.01) than alcohol extracts (with methanol 0.93±0.01—12.73±0.04, and with ethanol -0.85±0.01-- 7.70±0.03). In a similar trend, OHRSP (%) was higher in aqueous extracts (40.83±0.10--91.74±0.19) than alcoholic extracts (with methanol -11.67±0.3-- 30.83±0.06; and with ethanol -14.42±0.06- 40.27±0.05). TPC (mg/100g GAE) which was higher in alcoholic extracts (with methanol -21.48±0.01--133.20±0.16 and with ethanol -9.45±0.01--59.73±0.02) than aqueous extracts (14.83±0.01--52.64±0.03) was in agreement with the trend observed for NORSP (28.24±0.05-151.76±0.08 for methanolic extracts, 21.99±0.13--49.93±0.04 for ethanolic extracts and 38.47±0.11--86.15±0.05 for aqueous extracts). DPPHRSP was also higher in alcoholic extracts (methanolic -22.81±0.01-48.41±0.05 and ethanolic-- 14.53±0.01-62.68±0.07) than aqueous extracts (13.66±0.13--42.86±0.03). TFC, TPC and antioxidant activities showed concentration dependent increase and strong positive correlation with TFC (r= 0.926 – 0.997and r= 0.432 – 1.000) and TPC (r= 0.825 – 0.999 and r= 0.473 - 0.994) for L. taraxacifolia and C. rubens respectively. Caffeic acid, chlorogenic acid, ellagic acid, quercetin and kaempferol were identified as major phenolic components in the extracts. The vegetables have high antioxidant potential for promoting good health; which could be attributed to the identified phytochemicals in them. 

Funmilayo B. Borokini, Lajide Labunmi

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