Phenolic composition and antioxidant activities of saskatoon berry fruit and pomace.

Total phenolic chromatographic indices (TPCI) of three commercially grown saskatoon berry varieties and a pomace from commercial juice production were determined. Northline was shown to have the highest TPCI of 504.2 mg/100 g FW.

Structural identification of compounds for use in the detection of juice-to-juice debasing between apple and pear juices.

The ability to detect the undeclared addition of a juice of lesser economic value to one of higher value (juice-to-juice debasing) is a particular concern between apple and pear juices due to similarities in their major carbohydrate/polyol profiles. Fingerprint compounds for the detection of this type of adulteration were identified in both commercial apple and pear juices by HPLC-PDA, were isolated chromatographically, and structurally identified by LC-MS/MS. The apple juice fingerprint was identified as 4-O-p-coumarylquinic acid and two pear compounds as isorhamnetin-3-O-rutinoside and abscisic acid.

Analysis of a series of chlorogenic acid isomers using differential ion mobility and tandem mass spectrometry.

Chlorogenic acids are among the most abundant phenolics found in the human diet. Of these, the mono-caffeoylquinic acids are the predominant phenolics found in fruits, such as apples and pears, and products derived from them. In this research, a comprehensive study of the electrospray ionization (ESI) tandem mass spectrometric (MS/MS) dissociation behavior of the three most common mono-caffeoylquinic acids, namely 5-O-caffeoylquinic acid (5-CQA), 3-O-caffeoylquinic acid (3-CQA) and 4-O-caffeoylquinic acid (4-CQA), were determined using both positive and negative ionization.

Oligosaccharide formation during commercial pear juice processing.

The effect of enzyme treatment and processing on the oligosaccharide profile of commercial pear juice samples was examined by high performance anion exchange chromatography with pulsed amperometric detection and capillary gas chromatography with flame ionization detection. Industrial samples representing the major stages of processing produced with various commercial enzyme preparations were studied. Through the use of commercially available standards and laboratory scale enzymatic hydrolysis of pectin, starch and xyloglucan; galacturonic acid oligomers, glucose oligomers (e.

Authenticity analysis of pear juice employing chromatographic fingerprinting.

Pear juice is predominately composed of carbohydrates/polyols (>95% of the total soluble solids), making it susceptible to adulteration by the addition of less expensive commercial sweeteners. In this research, the major carbohydrate and polyol (fructose, glucose, sucrose, and sorbitol) content of 32 pure pear juices representing five world producing regions and three years of production was determined. Additionally, methods employing oligosaccharide profiling to detect the debasing of these samples with four commercial sweeteners (HFCS 55 and 90, TIS, and HIS) were developed using capillary gas chromatography with flame ionization detection (CGC-FID) and high-performance liquid chromatography with pulsed amperometric detection (HPAE-PAD).

Major carbohydrate, polyol, and oligosaccharide profiles of agave syrup. Application of this data to authenticity analysis.

Nineteen pure agave syrups representing the three major production regions and four processing facilities in Mexico were analyzed for their major carbohydrate, polyol, and oligosaccharide profiles, as well as their physicochemical properties (pH, °Brix, total acidity, percent total titratable acidity, and color). Additionally, the detection of intentional debasing of agave syrup with four commercial nutritive sweeteners (HFCS 55 and 90, DE 42 and sucrose) was afforded by oligosaccharide profiling employing both high performance anion exchange liquid chromatography with pulsed amperometric detection (HPAE-PAD) and capillary gas chromatography with flame ionization detection (CGC-FID). Results showed that the major carbohydrate and polyol in agave syrups were fructose and inositol with mean concentrations of 84.