Contents
01.12.2014.
Professional paper
Lipid composition of seed oils of different pomegranate (Punica granatum L.) cultivars from Spain
Pomegranate (Punica granatum L.) is an ancient fruit tree traditionally cultivated in the Near and Middle East. Presently, its most important growing regions include Afghanistan, Iran, Israel, USA, Italy and Spain, the latter country the largest European exporter. The pomegranate fruit can be divided into several anatomical compartments: outside peel, inside peel, and arils (pulp and seeds), the last part being usually used for consumption as is or for juice, jams and jellies production. Even though pomegranate seeds are an industrial by-product, recent reports have highlighted their potential use as a source of oil with beneficial chemical attributes. Therefore, the main objective of the present work was to characterize the seed oil of nine European pomegranate varieties, collected in Spain, for their fatty acid and vitamin E compositions. All seed lipid fractions consisted mainly of punicic acid (c9,t11,c13 C-18:3), ranging between 77.3% and 83.6% of total fatty acids, followed by small amounts of linoleic acid (C18:2n6), oleic acid (C18:1n9) and palmitic acid (C16:0). Regarding vitamin E composition, α-, γ-, δ-tocopherols were found in all pomegranate seed oils, but mainly γ-tocopherol, with total tocopherols ranging from 174.5 to 627.3 mg/100g oil.The richness of these pomegranate varieties seed oils in punicic acid, a conjugated linolenic acid with interesting anti-carcinogenic activity, and the elevated amount of tocopherols on the extracted lipids, of technological and nutritional relevance, make this by-product interesting for further exploitation.
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
Pumpkin seeds are commonly consumed in Greece. Although Cucurbita moschata is locally grown in Lemnos and is traditionally used in pumpkin pies, the seeds are currently discarded after consumption of the fruit flesh. The aim of the present study was to investigate the nutritional functionality of pumpkin seeds from Cucurbita moschata grown in Lemnos.Cucurbita moschatas’ seeds, raw or roasted, were appropriately extracted and the results are presented for raw versus (vs) roasted seed extracts. The phenolic content was expressed as μg gallic acid/g of seeds according to Folin-Ciocalteau assay (370.3 ± 19.1 vs 551.0 ± 22.0). Antioxidant capacity was expressed as equivalent amount for 50% scavenging in mg of seeds for DPPH (50.03 ± 5.91 vs 25.82 ± 6.77) and ABTS (17.85 ± 0.77 vs 12.77 ± 0.76) assays, and as μmol of trolox/g of seeds for FRAP (1.19 ± 0.05 vs 2.50 ± 0.23) and CUPRAC (2.13 ±0.11 vs 3.25 ± 0.06) assays. Anti-inflammatory/anti-thrombotic and anti-diabetic activities were expressed as mg of seeds for 50% inhibition of platelet activating factor (0.62 vs 0.15) and as μg of seeds for 25% inhibition of alpha-glycosidase (40.0 vs 61.0) activities respectively. Moreover, anti-atherogenic activity was expressed as the % increase in lag time of human plasma oxidation (62.7 versus 163.2)Raw and roasted pumpkin seed extracts exert anti-oxidant, anti-thrombotic/anti-inflammatory, anti-atherogenic and antidiabetic activities. Cucurbita moschata seeds may represent a novel opportunity for development of functional foods, with a local interest in Lemnos that would contribute also to the regional public health improvement.
Danai Sakka, Haralabos C. Karantonis
01.12.2014.
Professional paper
Information literacy training in AgroParisTech food studies
AgroParisTech professors and librarians in Food Science and Technology have developed information literacy instruction to help students find and use relevant information. The course trains students to develop information literacy competencies: to identify the information needed and define its nature and extent; to access the information with efficiency because they select and use methods, resources and retrieval systems most appropriate to the topic; to evaluate the used methods, information, and sources; to search, access and use information ethically and legally; to read, use and write bibliographic references.AgroParisTech trains two kinds of students. For Higher Education students (engineering students), the training takes place at their arrival in AgroParisTech, including courses and practical classes: role and management of information in organizations; information on plagiarism; resources in environment, food science and technology; use of relevant tools and methods for searching in databases; reference writing.For students attending a Master of Science, the training prepares them to produce a literature review. The curriculum includes: information about scientific integrity, plagiarism; information needed for a researcher; critical reading of a journal article; how to manage a literature review: resources used, information search with databases, full text access; reference writing.The students will use these information literacy skills along their studies as well as in their future jobs.
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
The influence of plasticizer type (glycerol and sorbitol), its content (starch:plasticizer ratio of 1:0.15; 1:0.20; 1:0.25 and 1:0.30) and the relative humidity conditions (43, 58, 75 and 85%) on the mechanical properties of cassava starch films was studied. Both plasticizers seemed to integrate homogeneously in the film matrix. The incorporation of different concentrations of plasticizers affected the mechanical properties of the cassava starch films. Plasticizer ratio directly influenced the force values of the films, they showed significant flexibility when the plasticizer proportion was increased in the formulation. Under conditions of low relative humidity, sorbitol produced films more resistant to puncture than glycerol. Qualitatively, all the films were less brittle when the plasticizers were incorporated.
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
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 López-Malo, María Teresa Jiménez-Munguía
01.12.2014.
Professional paper
Effect of incorporating alum in cane juice clarification efficiency and sucrose losses
The effect of incorporating alum in the clarification stage of raw juice in sugarcane processing on the juice quality and sucrose loss was investigated. Alum was incorporated in both intermediate and hot liming clarification processes of cane juicing. One portion of the cane juice was used for With Pre-treatment Treatment (WPT) while the other portion constituted No Pre-treatment (NPT) juice. Alum at levels of 0 mg L-1, 50 mg L-1, 100 mg L-1 and 150 mg L-1 was incorporated in both intermediate and hot liming clarification processes in each of the two cane juice portions. Sugar concentration (sucrose, glucose and fructose), oBrix, pH, colour, settling performance (initial settling rates (ISR), final mud volume (MV∞), and turbidity) and residual aluminium ion concentration were evaluated. Any significant variations (p < 0.05) in these parameters were assessed. The study found significantly lower (p < 0.05) sucrose losses in clarified juice from intermediate liming of WPT after alum treatment than in the rest of the clarified juices. Colour and turbidity in the pre-treated cane juice of intermediate liming was reduced by 36.9% and 98.1%, respectively at 150 mg L-1 alum level. An initial settling rate of 260 mL min-1 in WPT cane juice of intermediate liming at 150 mg L-1 alum level resulted in the most compact final mud volume of 10.3%. The residual aluminium concentration (0.025 to 0.048 mg L-1) in alum treated clarified juices was lower than the natural aluminium concentration (0.088 mg L-1) in untreated cane juice. This study showed the potential for the use of alum in cane juice clarification to improve on clarification efficiency and lower sucrose loss.
Benard M. Kimatu, Symon Maina Mahungu, Abdul K. Faraj, Symon M. Mahungu, Benard Muinde Kimatu
18.10.2014.
Original scientific paper
Blast-cooling of beef-in-sauce catering meals: numerical results based on a dynamic zero-order model
Beef-in-sauce catering meals under blast-cooling have been investigated in a research project which aims at quantitative HACCP (hazard analysis critical control point). In view of its prospective coupling to a predictive microbiology model proposed in the project, zero-order spatial dependence has proved to suitably predict meal temperatures in response to temperature variations in the cooling air. This approach has modelled heat transfer rates via the a priori unknown convective coefficient hc which is allowed to vary due to uncertainty and variability in the actual modus operandi of the chosen case study hospital kitchen. Implemented in MS Excel®, the numerical procedure has successfully combined the 4
th order Runge-Kutta method, to solve the governing equation, with non-linear optimization, via the built-in Solver, to determine the coefficient hc. In this work, the coefficient hc was assessed for 119 distinct recently-cooked meal samples whose temperature-time profiles were recorded in situ after 17 technical visits to the hospital kitchen over a year. The average value and standard deviation results were hc = 12.0 ± 4.1 W m−2 K −1 , whilst the lowest values (associated with the worst cooling scenarios) were about hc ≈ 6.0 W m−2 K −1 .Convective heat transfer
Jose Rabi, Evelyne Derens-Bertheau, Elisabeth Morelli, Isabelle Trezzani-Harbelot
18.04.2014.
Original scientific paper
The Regulation of Food Science and Technology Professions in Europe
The regulation of a profession is justified when it improves consumer protection and public health. Higher education food science and technology (FST) degrees, widely offered in many universities in Europe open to a wide range of jobs in the food sectors where the employees could cover different positions, roles and carry out diverse activities dealing with the food production and the quality and safety of the food products.This work reviews the state of the art of the FST regulated professions requiring higher education qualifications in the European countries. The research was carried out by collecting specific information on regulated professions by contacting unions, professional associations, public servant categories/professions, and by visiting national and EU websites. The data collected for each regulated profession were: country, training/education required, date of implementation of regulation, professional training (if required), capability test (if required) and acts required by law to be signed by a regulated professional. Only professions that required a higher education diploma were included in this search.Few countries were found to have a regulated profession in FST, in particular: Food Engineering (Turkey), Food Technologist (Greece, Iceland, Italy and Slovenia), and Oenologist (Italy, Portugal and Spain). FST regulated professions in Europe are thus scarce and have a rather limited history. The Food Technologist in Italy and the Food Engineer in Turkey were found to be the only completely regulated professions found in Europe. Food and professional regulation have been evolved over the years and raised the debate on the regulation of FST professions. Academia as well as other policymakers has to further contribute to this discussion to keep high the standards for quality of education and training of the qualified workforce and professionals in the food sector.
Rui Costa, Sonja Smole Možina, Paola Pittia
01.12.2013.
Professional paper
Characterization of potent odorant compounds in Turkish olive oils by GC-MS-olfactometric techniques
The purpose of this study was to determine the most powerful aroma-active compounds of olive oils obtained from Ayvalik (AYV), Gemlik (GEM) and Memecik (MEM) cultivars harvested in 2011, using gas chromatography-mass spectrometry-olfactometry (GC-MS-O). Simultaneous distillation and extraction (SDE) with dichloromethane was used for extraction of volatile components. The aroma-active compounds of olive oils were evaluated by aroma extract dilution analysis (AEDA). A total of 14, 12 and 12 aroma-active compounds within the range of ≥64–1024 flavor dilution (FD) factors were detected in aromatic extracts of olive oils obtained from AYV, GEM and MEM cvs., respectively. The compounds having the highest FD factor (1024) were (Z)-3-hexenol (cut grass, herbal) and β-sesquiphellandrene (floral) for AYV oil and (Z)-3-hexenyl acetate (fruity) for MEM oil. Among these compounds, terpenes were the overwhelmingly largest aroma-active components followed by aldehydes.
Songul Kesen, Hasim Kelebek, Serkan Selli
01.12.2013.
Professional paper
Effects of Lactic Acid Fermentation on the Retention of Β-Carotene Content in Orange Fleshed Sweet Potatoes
This study aimed to establish the effects of lactic fermentation on the levels of β-carotene in selected orange fleshed sweet potato (OFSP) varieties from Kenya. Furthermore,it sought to demonstrate fermentation as a potential process for making new products from sweet potato with enhanced nutraceutical attributes. The varieties (Zapallo, Nyathiodiewo and SPK004/06) were fermented with Lactobacillus plantarum MTCC 1407 at 25 ± 2°C for 48 h and kept for 28 days to make lacto-pickles. During fermentation both analytical [pH, titratable acidity (TA), lactic acid (LA), starch, total sugar, reducing sugar (g/kg roots), texture (N/m2), β-carotene (mg/kg roots)] and sensory (texture, taste, flavour and after taste) attributes of sweet potato lacto-juice were evaluated. Process conditions were optimized by varying brine levels, with fermentation time. A UV-visible spectrophotometer was used to identify and quantify β-carotene. Any significant variations (p < 0.05) in analytical attributes between the fermented and unfermented samples (pH, LA, TA and β-carotene concentration) of lacto-pickles, prepared from the potato roots, were assessed. The study reported a final composition of 156.49mg/kg, 0.53mg/kg, 0.3N/m2, 1.3g/kg, 5.86g/kg, 0.5g/kg and 5.86g/kg for β-carotene, Ascorbic acid, texture; Starch, total sugars, LA and TA respectively, and a pH of 3.27. The fermented products were subjected to flavour profiling by a panel. The product sensory scores were 1.5 to 2.5 on a 5 point hedonic scale, ranging from dislike slightly to like much. The products with brine levels at 4 and 6% were most preferred. The retention of β-carotene was 93.97%. This demonstrated lactic acid fermentation as a better method for processing OFSP as the main nutritional attributes are retained. The final product was resistant to spoilage microorganisms after 28 days of fermentation. Further preservation could be obtained by addition of sodium metabisulphite. In conclusion, Lactic acid fermentation using L. plantarum is a novel method of producing Lacto pickles from Zapallo OFSP, with 93.97% β-carotene retention and adequate shelf life.
Benard O. Oloo, A. A. Shitandi, S. Mahungu, J. B. Malinga, Rose B. Ogata