烘焙样本，薯片中粗脂肪检测方案(抽提萃取)

APPLICATION NOTEF&F-S-001-2015/A1 CRUDE FAT DETERMINATION IN CHIPSRANDALL METHOD Crude Fat Determination in Potato Chipsaccording to the Randall method Reference： AOAC Official Method 963.15 Tested with VELP Scientifica SER 158/6 Solvent AutoExtractor (Code F303A0380) Introduction Potato chips are the number one bestselling snack in the world followed by tortilla chips and crackers. They are thin slices of potato deep fried or baked until crunchy and salted. The snack food became massed-producedfor home consumption in 1910， when The Potato Chip Company， began manufacturing. Nowadays potato chips include flavors such as barbecue， sour cream & onion， salt & pepper， ham and many others.The food marketing in developing and developed countries is nowadays shifting on low fat diets， since diets and activity patterns had changed drastically， increasing the obesity rate at pandemic levels (Barry M. et al.， 2013). The fat content it's an important parameter to be showed in snacks labels， since the increased interest on this parameterby the consumers. Fat Determination in Potato Chips Hot solvent extraction process with SER 158 Series can be summed up in 5 steps， for a fully unattended operation： During IMMERSION the sample is immersed in boiling solvent. Then the REMOVING step automatically lowers the levelof the solvent to below the extraction thimble. During WASHING the condensed solvent flows over the sample andthrough the thimble to complete the extraction process. The fourth step involves solvent RECOVERY. Approximately90% of the solvent used is collected in the internal recovery tank. The final step is the COOLING of the extraction cupscontaining the extracted matter. The cups are raised to prevent burning. The extraction cups containing the extract areplaced in a drying oven， cooled in a desiccator and weighed for the extract percentage calculation. Sample Potato chips Fat labeled value： 28 g / 100 g Chemicals and Equipment Required ●Analytical balance， 3 decimals Petroleum Ether 40-60°C as solvent ●Extraction thimbles (33x80 mm) (Code A00000295) Sodium sulphate anhydrous Glass extraction cups Defatted cotton ●Viton seals Sample Preparation Fix the Extraction thimbles with the Extraction thimbles holders (Code A00000312). Grind around 20 g of potato chipsand put 3 g of (Sample) directly in the VELP extraction thimbles using the Thimble weighing cup (Code A00000310). Add about 2 g of sodium sulphate anhydrous and mix thoroughly using a glass rod. Clean the glass rod using a piece ofclean defatted cotton and place it into each thimble， over the sample. Position the extraction thimbles in the extraction cups. Glass Extraction Cups Preparation Position the empty extraction cups in an drying oven (105°C) for 1 hour. Cool them in a desiccator until constant weight of the tare (Tare). The extraction cups containing the extraction thimblecan now be placed on the ultra-fast heating plate of SER 158. Extraction Procedure with SER 158 On the ControlPad select“Analysis”， and then method“Fried potatoes” including the following parameters： · Immersion Time： 20 minutes Recovery Time 10 minutes ● RRemoving Time： 8 minutes自(Cooling Time： 5 minutes Washing Time： 20 minutes FPetroleum Ether 40-60°C， 100 ml Close the safety guard and add the solvent using the automatic solvent dispensing system SolventXpress to minimizeexposure to the solvent ensuring operator safety. Press START to begin the extraction process. At the end of analysis position the extraction cups containing the extractin a drying oven (1 hour at 105°C)， cooled them in a desiccator to room temperature and record the accurate weight(Total). Typical Results on Potato Chips Analysis results are calculated automatically and stored in the ControlPad when entering the weights into the software(manually or automatically through a balance). The extract percentage calculation is performed by using the followingformulas： Where： Sample= sample weight (g) Tare=weight of the empty extraction cup (g) Total = weight of the extraction cup + extract (g) Tare (g) Sample (g) Total (g) Extract (g) Extract (%) 122.191 2.857 123.006 0.815 28.52 123.298 3.018 124.157 0.859 28.46 122.994 2.922 123.821 0.827 28.30 123.221 2.954 124.062 0.841 28.46 123.307 2.804 124.111 0.804 28.67 124.817 2.904 125.646 0.829 28.54 Average±SD% 28.49±0.12 RSD% ** 0.43 Fat Labeled Value：28g/ 100 g Fat Labeled Value：28g/ 100 g ** RSD%= (Standard Deviation x 100) / Average Conclusion The results obtained are reliable and reproducible in accordance with the expected values， with a low relative standarddeviation (RSD< 1%)， that means high repeatability of the results. Therefore， SER 158 Solvent Extractor is ideal for the fat content determination in potato chips. Benefits of hot solvent extraction (Randall) by using 158 Automatic Solvent Extractor： -up to 5 times faster than Soxhlet (hot solvent vs. cold solvent) -low solvent consumption (high solvent recovery， approximately 90%)-limited cost per analysis - no exposure to solvent -worldwide official method - full traceability with automatic result calculation and on-board archive Copyright @ 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SER158全自动脂肪测定仪分析薯片中的粗脂肪含量:薯片是世界上最畅销的小吃，其次是玉米饼和饼干。它们是土豆片，油炸或烤至松脆并加盐腌。 休闲食品批量生产1910年马铃薯薯片公司开始生产时用于家庭消费。如今，薯片包括烧烤，酸奶油和洋葱，盐和胡椒粉，火腿等多种口味。发展中国家和发达国家的食品行销转向低脂饮食，因为饮食和饮食习惯这种模式已经发生了巨大变化，在大流行水平上增加了肥胖率（Barry M. et al。，2013）。脂肪含量是在零食标签上显示的重要参数，因为对此参数的兴趣有所增加受到消费者的欢迎。 具体的分析方法请下载全文。