New Method for Determining Total Dietary Fiber by Liquid Chromatography

Abstract

The molecular weight limit of water-soluble dietary fiber (SDF) determined by the Prosky method was studied by liquid chromatography (LC). It was confirmed that only SDF with an average degree of polymerization of 12 or higher can be determined by the Prosky method. Total dietary fiber (TDF) was determined by 2 additional methods using LC. In the first method, the total quantity of insoluble dietary fiber (IDF) and high molecular weight SDF (HMSDF) was determined according to the modified Prosky method (MES-TRIS buffer-based). The quantitatively collected final filtrate was analyzed by LC for the quantity of low molecular weight SDF (LMSDF), and the 2 quantities were totaled to obtain TDF. TDF values thus determined for rice, polished or unpolished, soybean flour, and pressed barley were higher than those determined by the Prosky method by approximately 6, 3.5, and 3.5%, respectively. In the second method, direct determination by LC analysis was done on samples after enzymatic treatment according to the Prosky method. Results showed that the determination of LMSDF, in particular, was highly accurate and more effective. In both of these methods, the quantity of LMSDF was determined from its chromatographic peak area ratio to glucose as an internal standard, which was produced by hydrolysis.

New starch preparations resistant to enzymatic digestion

“…Previously, it was demonstrated that the content of resistant fraction in dextrin D3, as determined by both the enzymatic-gravimetric AOAC 991.43 method 19 and the enzymatic-spectrophotometric method (Englyst method), 22 was significantly higher than that in dextrin D1. 21 In the present study the resistant fraction was determined by the official AOAC 2001.03 method 18 and the pancreatin-gravimetric method. 20 The AOAC 2001.03 method is the latest approved method for total dietary fibre determination in foods containing resistant maltodextrins.…”

“…Relative amount versus DP profiles were constructed. The average chain length of dextrins was determined by the method proposed by Koch et al 17 Determination of enzyme resistance of dextrins by AOAC 2001.03 method 18 At the first stage the sample was analysed as in the AOAC 991.43 method, 19 i.e. it was subjected to successive enzymatic hydrolysis by thermostable α-amylase, protease and amyloglucosidase.…”

Oral intake of slowly digestible α-glucan, isomaltodextrin, stimulates glucagon-like peptide-1 secretion in the small intestine of rats

“…BBMV were prepared from the mucosa by the method of Kessler et al (25) , in which maltase activity was measured by the method of Dahlqvist (26) , and frozen at -80°C until further use. In vitro digestibility of IMO and IMD was determined by our previously reported method (24) , which included the AOAC 2001.03 method (27) and an in vitro digestion method in which porcine pancreatic α-amylase (300 units/0•1 g of saccharides) and BBMV (1000-3000 units/0•1 g of saccharides as maltase activity) from rat small intestine were used (24) . In both methods, the resistance to in vitro digestion of IMO and IMD was defined as the yield of sugars after a digestion with a DP ≥ 2 and 3, respectively.…”

The Effect of Tartaric Acid-modified Enzyme-resistant Dextrin from Potato Starch on Growth and Metabolism of Intestinal Bacteria

“…392894 "Preparation with prebiotic qualities"). In previous research, Kapusniak et al [24] analyzed this dextrin in terms of the solubility and pH of its 1% aqueous solution, the content of reducing sugars, molecular mass distribution, weight average molecular mass using high performance size-exclusion chromatography (HPSEC), average chain length using high performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD), and the content of the resistant fraction using the enzymatic-gravimetric method AOAC 991.43 [25], the enzymatic-gravimetric-chromatographic method AOAC 2001.03 [26], the enzymatic-spectrophotometric method [27], and the pancreatin-gravimetric method [28]. It has been shown that the use of tartaric acid in the process of starch thermolysis yields acidic dextrin characterized by high water solubility (about 68%) and a high content of reducing sugars (about 29%).…”