High performance liquid chromatography and capillary electrophoresis in the analysis of soybean proteins and peptides in foodstuffs

Abstract

The increasing interest in functional and healthy food products has promoted the use of soybean in the manufacture of foods for human consumption. Soybean basic products (soybeans, textured soybean, soybean flour, soybean protein concentrate and soybean protein isolate) as well as soybean derivatives (soybean dairy-like products, soybean drinks with fruits, meat analogues, etc.) are commercially available. In addition, due to the interesting nutritional and functional properties of soybean proteins, they are usually employed as ingredient in the elaboration of a large number of food products such as bakery or meat products among others. In spite of the good characteristics of soybean proteins, their addition to some products is forbidden or allowed up to a certain limit. Therefore, analytical methodologies to achieve the determination of soybean proteins in foods are necessary in order to make possible adequate quality control and to prove that legal regulations controlling their addition are accomplished. However, this is not an easy task due to the diversity and complexity of the food matrices and the technological treatments to which some of these foods are submitted during their elaboration. This article presents for the first time a comprehensive review on the analytical methodologies developed using HPLC and CE to characterize soybeans and to analyse soybean proteins in meals. Moreover, the use of HPLC and CE in the characterization of soybean protein fractions and their hydrolyzates, and a study of their relationships to nutritional, functional and biomedical properties are included. Finally, the application of proteomic methodologies in soybean food technology is also reviewed.

Bioanalytical Methods for Food Allergy Diagnosis, Allergen Detection and New Allergen Discovery

“…Direct allergen detection and quantification are often realized by separation techniques such as LC [82,83] and CE [84] with UV [85][86][87][88] or fluorescence detection [89,90]. The utilization of such detectors suffers from false positive results due to the potential coelution of other compounds present in the sample matrix.…”

“…It insures unequivocal identification of amino acid order in the peptide starting from the N-terminal residue and is typically realized in parallel with de novo sequencing [82][83][84].…”

Proteomics: Emerging analytical techniques

“…An ion trap MS was used and MS conditions were optimized for both methods [65]. Furthermore, in one of the findings, CE is use to characterize soybean fractions and to analyze soybean proteins and by-products such soybean flour, soybean protein concentrate and soybean protein isolates and their hydrolyzates and a study of their relationships to nutritional, functional and biomedical properties [64].…”

Comparative Studies Involving Transgenic and Non-Transgenic Soybean: What is Going On?

“…Since the content of proteins in soybean seeds is high (ca. 40%) [7], hundreds of proteins are expected to be found after a separation process, making our proposal a hard task. Then, the utilization of the most up-to-date analytical techniques presenting high resolution in terms of enzymes, proteomics and metallomics approaches is almost imperative.…”