Chemometric analysis of amino acid profiles for detection of fruit juice adulterations - Application to verify authenticity of blood orange juice.

In this work, fruit juices have been analyzed by high-performance liquid chromatography (HPLC) to measure whole amino acid profiles for various fruit types. The fruit juice authentication capabilities of whole amino acid profiles employed in various multivariate analysis methods including principal component analysis (PCA) and partial least squares (PLS) analysis have been investigated. PCA of the profiles exhibited a good separation of most fruit types and were validated using quality control samples.

Origin authentication of distillers' dried grains and solubles (DDGS)--application and comparison of different analytical strategies.

In the context of products from certain regions or countries being banned because of an identified or non-identified hazard, proof of geographical origin is essential with regard to feed and food safety issues. Usually, the product labeling of an affected feed lot shows origin, and the paper documentation shows traceability. Incorrect product labeling is common in embargo situations, however, and alternative analytical strategies for controlling feed authenticity are therefore needed.

Screening for sulfate in distillers dried grains and solubles by FT-IR spectroscopy.

Distillers Dried Grains and Solubles (DDGS) are an animal feed containing varying levels of sulfur. As ruminants are susceptible to high sulfur diets, sulfur content is of major interest to the parties involved. The variation in levels of sulfur in DDGS is mainly due to sulfate derived from the addition of sulfuric acid during the production.

Authentication of the botanical and geographical origin of distillers dried grains and solubles (DDGS) by FT-IR spectroscopy.

Distillers dried grains and solubles (DDGS) were investigated with attenuated total reflection FT-IR spectroscopy both directly in their solid state and as the isolated oils (fat fractions). The collected spectra were evaluated in a first step with principal component analysis (PCA) according to the botanical origin (corn, rice, wheat) and the geographical origin (Canada, China, European Union, India, United States) of the DDGS. In a second step, statistical models were constructed for the characterization of the botanical and geographical origin using linear discriminant analysis (LDA) and soft independent modeling of class analogy (SIMCA).

Systematic comparison of tissue fixation with alternative fixatives to conventional tissue fixation with buffered formalin in a xenograft-based model.

In our study we systematically compared the alternative fixatives acidified formal alcohol (AFA), PAXgene®, HOPE®, and combinations of AFA or formalin with ultrasound treatment to standard (buffered) formalin fixation. We examined general morphology and detectability of protein structures by immunohistochemistry of the membrane receptors epidermal growth factor receptor (EGFR), insulin-like growth factor 1 receptor (IGF-1R), and phosphorylated human epidermal growth factor receptor 2 (phospho-HER2). In order to allow for stringent comparability of different fixation techniques, we used matched mouse xenograft tumor samples from three different human cancer cell lines (colon, ovarian, and non-small cell lung cancer), either fixed conventionally with formalin or an alternative fixative.