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PROCEEDINGS ZBORNIK --
CETVRTA MEDUNARODNA KONFERENCIJA ODRZIVE POSLEUBIRAJUCE I PREHRAMBENE TEHNOLOGIJE INOPTEP 2015 i XXVII NACIONALNA KONFERENCIJA PROCESNA TEHNIKA I ENERGETIKA U POLJOPRIVREDI PTEP 2015 19 – 24. april, 2015, DIVCIBARE, SRBIJA -
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INOPTEP 2015 PTEP 2015
FOURTH INTERNATIONAL CONFERENCE SUSTAINABLE POSTHARVEST AND FOOD TECHNOLOGIES INOPTEP 2015 and XXVII NATIONAL CONFERENCE PROCESSING AND ENERGY IN AGRICULTURE PTEP 2015 April 19th – 24th, 2015, DIVCIBARE, SERBIA
SCIENTIFIC COMMITTEE / NAUýNI ODBOR (Scientific Committee conducted a review of conference proceedings) INTERNATIONAL MEMBERS: Prof. Dr. Costas Akritidis, Emeritus Professor, Aristotle University, Thessaloniki, Greece, Prof. Dr. Silva Cristina, Portuguese Catholic University, Porto, Portugal, President of ISEKI-Food Association Prof. Dr. Harris Lazarides, Aristotle University, Thessaloniki, Greece, coopresident Dr. Gerhard Schleining, BOKU University, Wiena, Austria, Secretary General of ISEKI-Food Association Prof. Dr. Tajana Kriþka, University of Zagreb, Croatia, Prof. Dr. Zuzana Hlavaþova, University of Agriculture in Nitra,Slovakia, Prof. Dr. Zsuzsanna Füstös, Central Agricultural Office, Budapest, Hungary, Prof. Dr. Marko Dalla Rosa, University of Bologna, Italy, Prof. Dr. Richard Gladon, Iowa State University, USA, Prof. Dr. Jozef Horabik, Institute of Agrophysics Polish Academy of Sciences, Lublin, Poland, Prof. Dr. Costas Biliaderis, Aristotle University, Thessaloniki, Greece, Prof. Dr. Vlasta Vozárová, University of Agriculture in Nitra,Slovakia, Prof. Dr. Vangelþe Mitrevski, University "St Kliment Ohridski" Bitola, FYR Macedonia, Dr. Stavros Vougioukas, Aristotle University, Thessaloniki, Greece, Prof. Dr. Selim Škaljiü, Faculty of agriculture, Sarajevo, Bosnia and Hercegovina, Prof. Dr. Ingid Bauman, University of Zagreb, Croatia, Prof. Dr, Drago Šubariü, University of Josip Juraj Strossmayer Osijek, Croatia, Prof. Dr. Dorota Kregiel, University of Technology, Lodz, Poland, Dr. Branimir Šimiü, Agricultural Institute Osijek, Croatia, Prof. Dr. Nikolai Mihailov, “Angel Kunchev” University, Ruse, Bulgaria. NATIONAL MEMBERS: Prof. Dr. Mirko Babiü, Faculty of Agriculture, Novi Sad, General Secretary of National Society of Processing and Energy in Agriculture, president Prof. Dr. Ljiljana Babiü, Faculty of Agriculture, Novi Sad, Vice-president of National Society of Processing and Energy in Agriculture, Dr. Jovanka Leviü, Institute of food technology, Novi Sad, Prof. Dr. Milica Radosavljeviü, Maize Research Institute “Zemun Polje”, Belgrade, Vice-president of National Society of Processing and Energy in Agriculture, Prof. Dr. Dragan Škoriü, Serbian Academy of Science and Arts, Belgrade Prof. Dr. Anÿelko Bajkin, Faculty of Agriculture, Novi Sad, Prof. Dr. Dušan Miliü, Faculty of Agriculture, Novi Sad, Prof. Dr. Filip Kuliü, Faculty of Technical Science, Novi Sad, Prof. Dr. Dragan Markoviü, Mechanical Faculty, Belgrade, Prof. Dr. Miloš Tešiü, Faculty of Technical Science, Novi Sad, Dr. Milka Vujakoviü, „Poljoprivredna stanica” Ltd, Novi Sad, Serbia, Dr. Lana Ĉukanoviü, Institute for Plant Protection and Environment, Belgrade, Prof. Dr. Ljiljana Mojoviü, Faculty of Technology and Metallurgy, Belgrade, Dr. Svetlana Baleševiü-Tubiü, Institute of field and vegetable crops, Novi sad, Prof. Dr. Maša Bukurov, Faculty of Technical Science, Novi Sad, Dr. Rade Stanisavljeviü, Institute for Plant Protection and Environment, Belgrade, Dr. Aleksandra Dimitrijeviü, Faculty of Agriculture, Belgrade, Dr. Branislav Karadžiü, Faculty of Agriculture, Novi Sad. Dr. Ivan Pavkov, Faculty of Agriculture, Novi Sad. Publisher / Izdavaþ National Society of Processing and Energy in Agriculture, Novi Sad, Serbia Nacionalno društvo za procesnu tehniku i energetiku u poljoprivredi, Novi Sad, Trg Dositeja Obradoviüa 8 Co-publisher / Suizdavaþ Faculty of Agriculture, Novi Sad, Serbia Poljoprivredni fakultet, Novi Sad, Trg Dositeja Obradoviüa 8 Editor in Chief / Glavni i odgovorni urednik: Prof. dr. Mirko Babiü Editors / Urednici Prof. Dr. Anÿelko Bajkin MSc Milivoj Radojþin Dr. Ivan Pavkov For Publisher / Za izdavaþa: Dr. Velimir Lonþareviü Technical editor / Tehniþki urednik: MSc Milivoj Radojþin, Dr. Ivan Pavkov Printed by / Štampa: Offsetprint, Novi Sad, Primorska 84 Edition / Tiraž: 200 ISBN: 978-86-7520-333-9 E-mail:
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4th INTERNATIONAL CONFERENCE SUSTAINABLE POSTHARVEST AND FOOD TECHNOLOGIES INOPTEP 2015 AND 27th NATIONAL CONFERENCE PROCESSING AND ENERGY IN AGRICULTURE PTEP 2015, April 19th – 24th, 2015, Divþibare, Serbia
THE INFLUENCE OF EXTRUSION PROCESSING AND STORAGE CONDITIONS ON THE FATTY ACID STABILITY IN ANIMAL FEED Sanja POPOVIû*, Ljiljana KOSTADINOVIû, Jovanka LEVIû, Ĉuro VUKMIROVIû, Radmilo ýOLOVIû, Vojislav BANJAC, Dušica ýOLOVIû University of Novi Sad, Institute of Food Technology, Bulevar cara Lazara 1, 21000 Novi Sad, Serbia Contact:
[email protected] ABSTRACT The aim of the study was to examine the thermal stability of untreated and extruded samples of animal feed and optimal shelf life of mentioned feeds. First sample was extruded mixture of linseed and sunflower meal, while untreated mixture was used as a control feed. Both samples were stored under extreme conditions in the Climate chamber (at temperature of 60ºC/ relative humidity 80 %) and in the storehouse (at temperature 23ºC/ relative humidity 54 %). The peroxide value was analyzed after each week, a total of three months. The extrusion process slightly postponed the lipid oxidation and reduced peroxide value maximum of treated sample stored under extreme conditions. Results also showed that one day in Climate Chamber has the same effect on lipid oxidation like one month of storage in storhouse. Obtained results are valuable regarding monitoring and shelf life of animal feeds that can be determined in a few days. Key words: thermal stability, lipid, storage, feed, extrusion, peroxide value INTRODUCTION In last decade, the consumption of food enriched with polyunsaturated fatty acids (PUFA) has been studied widely, considering that oxidation of these compounds is crucial for development of numerous cardiovascular diseases. The control of lipid oxidation is required in order to prevent the losses of nutritional and organoleptic values and to prevent production of potentially toxic compound in human, but animal food too (Galobart et al., 2001). In last decades, feed processing is widely used in animal feed production. The processing includes a numerous operations such as receiving, grinding, proportioning, mixing, pelleting, expanding or extrusion. All of these steps can have positive and negative effects on nutritionally value components of raw materials used in production (Behnke and Beyer, 2002). For instance, these processes are harmful to labile nutrients, such as vitamins, that can be easily oxidized (Kostadinoviü et al., 2013). A lipoxygenase, present in many plants, catalyze the oxidation of some unsaturated fatty acids (Lin et al., 1998). However, this compound can be also inactivated during heat processing (Guzman et al., 1992). Extrusion inactivation of lipase and lipoxygenase helps protect against oxidation during storage, but the porosity of expanded feed is detrimental with respect to rancidity (Zadernowski, 1997). On the other hand, the digestibility may be increased or the palatability improved using heat processing (Riaz, 2007). Moreover, the pathogen reduction may be achieved applying thermal processing of feed (Kostadinoviü et al., 2014). The feed manufacturers tend to have method which will give reasonably indication of shelf life of products in a relatively short period of time. The imitation of storage conditions, but under extreme parameters, is one of the possible ways to obtain the desired results in the shortest period of time. The objective of the present study was to examine the thermal stability of untreated and extruded samples of animal feed and optimal storage conditions regarding stability of lipids and the shelf life of mentioned feeds.
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4th INTERNATIONAL CONFERENCE SUSTAINABLE POSTHARVEST AND FOOD TECHNOLOGIES INOPTEP 2015 AND 27th NATIONAL CONFERENCE PROCESSING AND ENERGY IN AGRICULTURE PTEP 2015, April 19th – 24th, 2015, Divþibare, Serbia
MATERIAL AND METHOD Samples Two samples were investigated in present study: x Untreated mixture of linseed and sunflower meal (UTM), x Extruded mixture of linseed and sunflower meal (EXM). Grinding of linseed and sunflower meal was done by hammer mill (ABC Engineering, Panþevo, Serbia), driven by 2.2 kW electric motor, with a rotational speed of 2880 rounds per minute and 16 hammers arranged in four rows. Diameter of used sieve was 31 cm, and sieve openings diameter was 4 mm. Milled linseed and sunflower meal was mixed in a ratio 1:1 using double-shaft pedal mixer, model SLHSJ0.2A (Muyang, Yangzhou, China). Obtained mixture was used as an untreated mixture (UTM). Extrusion conditions In a mixture, obtained as described above, addition of water was done directly into mixer during mixing, in order to achieve final moisture content (12,5 ± 0,5 %). The mixture was extruded using single screw extruder, OEE 8, AMANDUS KAHL GmbH & Co. KG, Germany, with a length-to-diameter ratio of 8.5:1 and one die with 5 mm diameter opening and total opening area of 19.8 mm2. The final product was obtained at 70 °C with screw speed of 300 RPM and passage of the material that was 21.3 kg/h. The extrudates (EXM) were stored for 24 hours under room conditions in order to achieve stabile temperature and then were ground by hammer mill with a sieve openings of 4 mm. Vitamin E was added in both, starting linseed/sunflower meal mixture and grinded extruded product, at level of 1.35 g/kg. Addition of vitamin E was done in a double-shaft pedal mixer of laboratory vacuum coater F-6-RVC (Forberg International AS, Norway). Samples were stored in glass bottles (370 ml volume) in the Climate chamber Binder KBF series (E5.2), (Binder GmbH, Tuttlingen, Nemaþka), in the dark at the temperature of 60ºC and at the relative humidity of 80 %, but in the storehouse also (at temperature 23ºC and relative humidity 54 %) to carry out analysis of peroxide value. Samples stored under these conditions were analysed after each week, a total of three months (12 weeks). Extraction of total lipids Total lipids were extracted from samples using Soxhlet method with semi-automatic system (SOXTEC HT 1043, Tecator, Denmark) and petroleum ether (AOAC 920.39 Method). Determination of peroxide value The peroxide value was determined following the AOAC Method (965.33) with some modiÞcations. In brief, 1.0 g of homogenized milled sample was weighed with accuracy of ±0.001 g and was dissolved in 10 mL of a mixture of glacial acetic acid/chloroform (3:2 v/v) and 0.2 mL of saturated potassium iodide solution was added and the reaction mixtures were left to stand for 1 min at room temperature (about 25 °C) with occasional shaking. Twenty (20) milliliters of distilled water were then added to the sample and then the liberated iodine was titrated with a solution of 0.01N sodium thiosulfate. The results are reported as mmol O/kg oil. A blank titration was carried out using a sample containing all the above reagents except to oil sample. Data Analyses The one way ANOVA analysis was performed to assess data differences between various groups using Statistica software version 12 (StatSoft inc. 2013; USA). Duncan´s multiple range test was used to compare results between treated groups. The data means were considered different at P
