野鼠尾草籽中油脂氧化稳定性检测方案(氧化分析仪)

APPLICATION NOTEF&F-0-001-2016/A1 Oxidation Stability of Chia seedsflour Reference： International Standard Procedure AOCS Cd 12c-16 Tested with VELP Scientifica OXITEST Oxidation Stability Reactor (Code F30900248) Introduction Many studies have demonstrated that an increased intake of saturated lipids and trans-fatty acids is closely related tothe incidence of cardiovascular disease， whereas the consumption of lipids rich in w-3 fatty acids reduces the risk of thispathology. Chia (Salvia hispanica L.) seed is among the richest natural source of a-linolenic acid (C18：3) whichnutritionally represents the most important source of w-3. Chia is a food crop originating from central America， importantin the diet of pre-Columbian civilizations and the use of Chia seeds as a novel food ingredient has been approved by theEuropean Parliament and the European Council. Oxidation Stability in Food One of the most important quality alteration of food is due to oxygen absorption by the unsaturated fatty acids， free oresterified. The auto-oxidation of fats is a chemical reaction promoted by oxygen， light， high temperatures， metal tracesand， sometimes， enzymes. OXITEST can determine the oxidation stability of various sample types， without the need for preliminary fat separation. OXITEST Principle OXITEST speeds up the oxidation process because of the two accelerating factors， temperature and oxygen pressure，according to the most common applications. The instrument measures the absolute pressure change inside the two chambers， monitoring the oxygen uptake byreactive components in the sample and automatically generates an IP value. IP Definition： IP stands for Induction Period and it is the time required to reach the starting point of oxidation， corresponding to either alevel of detectable rancidity or a sudden change in the rate of oxidation. The longer the Induction Period， the higher the st abilityagainst oxidation over time. Sample Chia seeds flour Fat labeled value： 30 % Equipment and Chemicals ●·AAnalytical balance， 3 decimals●Silicone grease●。 Grinder· Oxygen， purity grade 5.0 Sample Preparation Store the samples at room temperature. Chia seeds flour is already milled and doesn’t require any homogenization.Pour 10 grams of sample directly on the surface of the titanium sample holder， by using a spatula. In each reaction chamber (A and B)， place 2 spacers and one sample holder containing the sample. Analysis Procedure Grease the O-rings with silicon grease and set them in their position. Close the chambers with the titanium covers andturn the discharge valves in open position. Set the following conditions on the OXISoftTM software： Temperatures： 80-90-100°C Oxygen Pressure： 6 bars When the temperature set is reached inside the chambers， close the discharge valves and start loading oxygen.Data acquisition is automatically started by the software. Typical Results on Chia seeds flour Chia seeds flour sample has been tested at 80， 90 and 100 °C. At the end of the oxidation tests， the IP of every run isautomatically calculated by the software OXISoft M. Date [dd/mm/yy] File Name Set point T[C] Set point P[bar1 IP [h：m1 SD[h：m] RSD[%] 25/04/16 Chia Seeds Flour 80°C 80.0 6.00 62：55 0：16 0.4 27/04/16 Chia Seeds Flour 90°C 90.0 6.00 20：56 0：02 0.2 26/04/16 Chia Seeds Flour 100°C 100.0 6.00 7：11 0：29 6.9 Estimated Shelf Life The graph below shows the correlation between IP and temperature. Using IP results obtained at different temperatures， in the case of a linear equation between results， it’s possible to havea prediction of the shelf life of the product at the storage temperature (e.g. 25°C)， easily extrapolated by the dedicatedOXISoftMprocedure“Estimated shelf life”. Conclusion The correlation between In(IP) results obtained at different temperatures is linear (R²=0，999932). The OXISoft resultsestimate the resistance to oxidation of the chia seeds flour at the storage temperature of 25 °C. The Oxitest allows the estimation of the shelf life of chia seeds flour in a considerably reduced time， obtaining the sameresult. Benefits of OXITEST are： Test is made directly on the whole sample No need for preliminary fat separation of the sample Resistant titanium chamber Time saving analysis， if compared to the traditional methods . Especially designed for R&D， Product Development and Quality Control labs Many investigations available through the software OXISoftTM： 1. Repeatability test： a series of tests run on the same sample or standard to verify its IP period， to calculateaccuracy and repeatability of the data 2. Freshness test： to verify the quality of different lots， for example of the same raw material， and compare them 3. Formula comparison： to identify the most stable formula of a finished product， under the same conditions 4. Packaging comparison： for testing which packaging maintains the product in the freshest condition 5. IP during ageing： to obtain a graph of the decrease of the product IP during the shelf-life period 6. Estimated shelf life： to have a prediction of oxidation stability during the shelf life Copyright C VELP Scientifica. All rights reserved.No part of this publication may be reproduced or transmitted in any form or for any purpose without the express permission of VELP.VELP Scientifica， Italy Tel： + Fax： + www.velp.com 利用VELP OXITEST野鼠尾草籽的氧化稳定性分析/货架期分析；OXITEST油脂氧化分析仪的结果可以以表格的形式显示反应温度，诱导时间，标准偏离等信息。OXITEST油脂氧化分析仪可以进行货架期预测