Theander O, Aman P, Westerlund E, Andersson R, Pettersson D
Swedish University of Agricultural Sciences, Department of Chemistry, Uppsala.
J AOAC Int. 1995 Jul-Aug;78(4):1030-44.
A joint AOAC/American Association of Cereal Chemists (AACC) collaborative study was conducted to determine by the Uppsala method the dietary fiber content and its composition in various foods. The method includes preparation of a residue by treatment with thermostable alpha-amylase and amyloglucosidase and then ethanol precipitation of solubilized dietary fiber components while leaving low-molecular weight carbohydrates in solution. After acid hydrolysis of residue, neutral polysaccharide residues are determined as alditol acetates by gas-liquid chromatography, uronic acid residues are determined by colorimetry, and ash-free acid-insoluble residue (Klason lignin) is determined gravimetrically. Total dietary fiber, including enzyme-resistant starch, is calculated as the sum of nonstarch polysaccharide residues and Klason lignin. Nine laboratories completed the study, analyzing in duplicate 8 unknown dried products that included 4 cereal products, green peas, potato fiber, carrots, and apples. Total dietary fiber contents of products tested ranged from 4.6 to 84.3%, with an average RSDR value of 8.4% (range, 4.8-11.1%). Total neutral polysaccharide residues ranged from 3.8 to 64.1%, with an average RSDR value of 7.5% (range, 5.4-10.5%). Individual neutral sugars (rhamnose, arabinose, xylose, mannose, galactose, and glucose) and uronic acid residues present at more than 1% generally had good RSDR values (3.3-22.8%), whereas, as expected for Klason lignin, only the wheat bran sample with a high content (16%) had an excellent RSDR value (5.0%). The gas chromatographic-colorimetric-gravimetric method (Uppsala method) for determination of total dietary fiber (as neutral sugar residues, uronic acid residues, and Klason lignin) has been adopted first action by AOAC INTERNATIONAL.
美国官方分析化学师协会（AOAC）和美国谷物化学家协会（AACC）联合开展了一项协作研究，旨在采用乌普萨拉方法测定各类食品中的膳食纤维含量及其组成。该方法包括先用耐热α-淀粉酶和糖化酶处理制备残渣，然后对溶解的膳食纤维成分进行乙醇沉淀，使低分子量碳水化合物留在溶液中。残渣经酸水解后，中性多糖残渣通过气液色谱法测定为糖醇乙酸酯，糖醛酸残渣通过比色法测定，无灰酸不溶性残渣（克拉森木质素）通过重量法测定。包括抗酶解淀粉在内的总膳食纤维按非淀粉多糖残渣和克拉森木质素之和计算。九个实验室完成了这项研究，对8种未知干燥产品进行了双份分析，这些产品包括4种谷物产品、青豆、马铃薯纤维、胡萝卜和苹果。测试产品的总膳食纤维含量在4.6%至84.3%之间，相对标准偏差（RSDR）平均值为8.4%（范围为4.8 - 11.1%）。总中性多糖残渣在3.8%至64.1%之间，RSDR平均值为7.5%（范围为5.4 - 10.5%）。含量超过1%的单个中性糖（鼠李糖、阿拉伯糖、木糖、甘露糖、半乳糖和葡萄糖）和糖醛酸残渣通常具有良好的RSDR值（3.3 - 22.8%），而正如克拉森木质素所预期的那样，只有含量高（16%）的麦麸样品具有出色的RSDR值（5.0%）。用于测定总膳食纤维（作为中性糖残渣、糖醛酸残渣和克拉森木质素）的气相色谱 - 比色 - 重量法（乌普萨拉方法）已被AOAC INTERNATIONAL首次采用为暂行方法。
