Quality assessments of untreated and washed quinoa (Chenopodium quinoa) seeds based on histlogical and foaming capacity investigations

Quinoa seed has a high nutritional value, but has a coating of bitter-tasting saponins, making it unpalatable. Therefore the seeds are usually processed in order to remove the naturally occurring saponins from the seeds. To investigate the impact of processing, untreated and washed seeds of the white and brown types of quinoa were investigated histologically and by foaming capacity evaluations. Reference samples of known origin and treatment were investigated as well as unknown samples. The results revealed a relationship between the presence of saponin containing papillose cells at the outermost layer of the seed hull in the histological sections and the foaming capacity of the seeds. After washing, the papillose cells were severely damaged or completely removed and virtually no foam formation was observed. This investigation indicatedthat washing resulted in an effective removal of the saponin layer, leading to quality improvement of the seeds intended for human and animal consumption. The same features were observed for the unknown samples. These results imply that the treatment of the investigated samples was based on washing. The determination of the type of treatment applied provided useful information for the correct tax classification for Custom purposes

The 2008 Dutch NRL/IAG proficiency test for detection of animal proteins in feed

The results of a proficiency test for the detection of animal proteins in animal feed by microscopy, PCR (DNA detection) and immunoassay methods are presented in this report

The microscopic detection of animal proteins in feeds

In the framework of the European Union funded research project STRATFEED for detection and identification of animal proteins in feeds, the microscopic method was optimized at several key steps and better documented. A check list was developed for uniform reporting. Characters of bone fragments, hairs, muscles and gills are fully documented. A so-called muscle ratio has been developed for the identification of muscle fibers at the level of vertebrate classes (mammals, birds and fishes). Both the improved protocol and the entire range of characters which can be observed, are documented in a Decision Support System called ARIES (Animal Remains Identification and Evaluation System). A second internet-based system called STRATFEED-DSS exclusively assists in identification of animal particles in feeds. A new strategy with microscopy as screening technique and either DNA or protein identification as confirmation technique is proposed. The advantages of this combination are the extremely low level of false negatives, low detection limits and the heat-resistant nature of microscopic detection, together with the possibility of a very specific identification of particles by one of the other methods