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Volume 13, Issue 2, 2024
Online ISSN: 2182-1054
Volume 13 , Issue 2, (2024)
Published: 18.10.2024.
Open Access
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Contents
18.04.2015.
Original scientific paper
Evaluating the Ultra-High Pressure Homogenization (UHPH) and Pasteurization effects on the quality and shelf life of donkey milk
Donkey milk has functional properties of great interest to human nutrition. The effects of ultra-high pressure homogenization (UHPH) at 100 MPa, 200 MPa and 300 MPa in comparison with different pasteurization treatments of 70 ◦C for 1 min and 85 ◦C for 1 min on the physicochemical quality and shelf-life of treated and raw (untreated) donkey milk were studied. Gross composition and pH, total mesophilic counts, lysozyme activity and physical stability were studied during storage at 4 ◦C for 28 days. The compositional profile showed resemblance to that of human milk characterized by high lactose, low fat and low protein content and was least affected by the treatments. UHPH treatments at 200 MPa, 300 MPa and 85 ◦C were able to maintain steady pH during storage whereas the low intensity treatments showed a significant decrease. The observed lysozyme activity in the samples was generally high and appeared to have been enhanced by the applied UHPH and pasteurization treatments with no significant change during storage. Although the raw milk showed good initial microbial quality, extensive growth of mesophilic microorganisms occurred after 7 days of storage, unlike the treated samples which were able to maintain significantly low counts throughout the storage period. The physical stability of milk was negatively influenced by the higher UHPH treatments of 200 MPa and 300 MPa which exhibited sedimentation phenomenon, while creaming was insignificant.
Cephas Nii Akwei Addo, Victoria Ferragut
18.04.2015.
Original scientific paper
Training requirements for agro-food industry in Portugal
Agro-food companies are aware that the technical and soft skills of their employees directly influence business performance and, consequently, improving those skills will enhance the effectiveness and efficiency of their companies. This paper presents the main results of the AgriTraining project “Training requirements for the agro-food industry”. Activities in pursuit of the objectives of this project involved: (1) analysis of the training needs in the agro-food industry in Portugal; (2) analysis of the training provision and the training organizations; (3) analysis of market trends; (4) definition of a training strategy; and (5) adjustment and development of training strategies for the agro-food sector. This last activity comprised the development of training curricula, suitable for the food sector as a whole and adjusted for the specific needs of some traditional industries, in order to promote the development and competitiveness of the agro-food industry in Portugal. Such training curricula aimed to promote the uptake of innovative technologies and methodologies, increase the ability of agro-food industries to invest and take risks, and enable adoption of European Community standards for production and marketing. Gaps in training supply were identified and the training provision was updated according to the needs of the agro-food companies. It was determined that companies need and demand knowledge and innovation to increase their competitive position for internationalization purposes. It was possible to define a training strategy based on market-orientation for agro-food differentiation.
Pedro D. Gaspar, Rita Pinheiro, Claudia Domingues, Celestino Almeida, Teresa Paiva, Carlos D. Pereira, Manuela Vaz Velho
18.10.2015.
Original scientific paper
Microencapsulation of steviol glycosides (Stevia rebaudiana Bertoni) by a spray drying method – Evaluation of encapsulated products and prepared syrups
The aim of this study was to encapsulate the steviol glycosides (SGs), derived from Stevia rebaudiana (Bert) Bertoni leaves, by applying a spray-drying method. The purpose was to minimize the bitter aftertaste of the SGs as well as to ameliorate/improve their properties. The encapsulation agents used were maltodextrin (19 DE) and inulin in a ratio of 80 : 20, while three levels of SGs in total solids (1.5, 2.5 and 3.5 %) were studied. The encapsulated SGs products were evaluated for their hygroscopicity, solubility, moisture content and microencapsulation efficiency (MEE %). Also, syrups prepared with encapsulated SGs, at 1 % w/v, were tested for their viscosity, refractive index, turbidity and sensory properties. Significant differences (P<0.05) in MEE %, moisture content, hygroscopicity and solubility values of the encapsulated SGs products were observed depending on the level of SGs in total solids. In particular, the MEE %, the hygroscopicity and the solubility values ranged from 62.36, 82.46 to 94.67 %, 21.51, 26.67 and 24.25 % and 99.93, 97.50 to 96.03 % for encapsulated SGs products produced with 1.5, 2.5 and 3.5 % SGs in total solids, respectively. The encapsulated product produced with 2.5 % steviol glycosides in total solids presented the most appealing sensory and quality characteristics.
Charikleia Chranioti, Sofia Chanioti, Constantina Tzia
18.10.2015.
Original scientific paper
Simple and double microencapsulation of Lactobacillus acidophilus with chitosan using spray drying
The aim of this study was to evaluate the survival of Lactobacillus acidophilus that had been simple or double spray dried using chitosan to cause microencapsulation and which had been exposed to model gastrointestinal conditions. In addition, the study also determined the physicochemical properties of the powder containing the microencapsulated probiotic. Chitosan-inulin or chitosan-maltodextrin (1:15 or 1:25) solutions were inoculated with 1012 CFU mL−1 of L. acidophilus, for simple microencapsulation. The different solutions were dried using a spray dryer with an inlet air temperature of 130 ◦C and a solution flux of 4.8 g min−1 . A two-step process was used for the double microencapsulation. In the first step, the probiotic was added to a gelatin-maltodextrin (1:25) solution and then spray dried; for the second step, the microencapsulated probiotic was added to a chitosan-inulin or chitosan-maltodextrin (1:25) solution and then it was spray dried again. With the simple microencapsulated probiotic, a microbial reduction of 7 log cycles was obtained. With the double microencapsulated probiotic only 3 log reductions were achieved. The double microencapsulated probiotic thus demonstrated greater resistance to simulated gastrointestinal conditions. The powders produced were shown to have water activity values of 0.176 - 0.261 at 25 ◦C and moisture content of 0.8 – 1.0%, which are characteristic of spray dried products. The bulk density was significantly (p < 0.05) lower (300 kg m−3 ) for simple than for double (400 kg m−3 ) microencapsulated probiotic powders. Solubility and dispersibility of the powder microcapsules were better at lower pH values. Double microencapsulation using a process of spray drying is therefore recommended for probiotics, thus exploiting chitosan’s insolubility in water, which can be applied for the of development food products.
Isela A. Flores-Belmont, Enrique Palou, Aurelio Lopez-Malo, María Teresa Jiménez-Munguía, Aurelio Lopez-Malo
18.10.2015.
Original scientific paper
Probiotic fermented almond “milk” as an alternative to cow-milk yoghurt
Probiotics in almond-based matrices were considered as a means of obtaining fermented products which would cover both the current demand for health-promoting foods and for alternatives to standard yoghurts. Firstly, the combined effect of high pressure homogenisation (HPH) and heat treatment on the physical stability of almond “milk” was studied. The beverage was homogenised by applying 62, 103 and 172 MPa (MF1, MF2 and MF3 respectively); MF3 was also combined with two different heat treatments (85 °C-30 min (LH) and 121 °C-15 min (HH)). Both microstructure and colloidal stability were analysed in all the processed samples to select the most suitable treatment with which to obtain a stable product. The selected almond milk was then fermented with probiotic Lactobacillus reuteri and Streptococcus thermophilus and the final product was characterised throughout cold storage time (28 days) as to pH, acidity, serum retention and starter viability. A sensory evaluation and probiotic survival to in vitro digestion was also conducted. The results showed that the physical and structural almond-milk properties were affected by both HPH and heat treatments, obtaining the greatest stability in MF3-LH samples. The fermented milk permitted probiotic survivals above the level suggested as minimum for ensuring health benefits during the entire controlled time and, hence, can be considered as a functional food. No differences in the sensory acceptability of the product were found between 1 and 28 storage days. Therefore, a new, functional, fermented product was developed, which was suitable for targeted groups, such as the lactose-intolerant and cow-milk-protein allergic populations.
Neus Bernat, Maite Chafera, Amparo Chiralt, Chelo Gonzalez-Martınez
01.12.2014.
Professional paper
Lipid composition of seed oils of different pomegranate (Punica granatum L.) cultivars from Spain
Luana Fernandes, José A. Pereira, Isabel Lopéz-Cortés, Domingo M. Salazar, Elsa Ramalhosa, Susana Casal
01.12.2014.
Professional paper
In vitro health beneficial activities of Pumpkin seeds from Cucurbita moschata cultivated in Lemnos
Danai Sakka, Haralabos C. Karantonis
01.12.2014.
Professional paper
Information literacy training in AgroParisTech food studies
Agnès Grimal, Florence Dubois-Brissonnet, Elisabeth Dumoulin
01.12.2014.
Professional paper
Mechanical properties of cassava starch films as affected by different plasticizers and different relative humidity conditions
Jeannine Bonilla Lagos, Nívea M. Vicentini, Rodolfo M.C. Dos Santos, Ana Mônica Q.B. Bittante, Paulo J. A. Sobral
01.12.2014.
Professional paper
Effect of incorporating alum in cane juice clarification efficiency and sucrose losses
Benard M. Kimatu, Symon Maina Mahungu, Abdul K. Faraj, Symon M. Mahungu, Benard Muinde Kimatu