This project was initiated with the goal of investigating the malt quality of winter rye cultivars and hybrids grown in the United States in 2014 and 2015, but high levels of deoxynivalenol (DON) were subsequently found in many of the malt samples. DON levels in 75% of the investigated rye samples (n = 117) were actually below 1.0 mg/kg, as quantified by a gas chromatography combined with electron capture detector (GC-ECD).
View Article and Find Full Text PDFJ Agric Food Chem
March 2012
This paper reports the first isolation from cultures of two endoxylanases secreted by Fusarium graminearum Schwabe [teleomorph Gibberella zeae (Schweinitz) Petch]. When F. graminearum is grown on wheat bran hydrated with a modified synthetic medium, high xylanase activity can be extracted.
View Article and Find Full Text PDFGibberella zeae, the principal cause of Fusarium head blight (FHB) of barley, contaminates grains with several mycotoxins, which creates a serious problem for the malting barley industry in the United States, China, and Europe. However, limited studies have been conducted on the trichothecene profiles and population genetic structure of G. zeae isolates collected from barley in the United States.
View Article and Find Full Text PDFFusarium graminearum, a known producer of trichothecene mycotoxins in cereal hosts, has been recently documented as a cause of dry rot of potato tubers in the United States. Due to the uncertainty of trichothecene production in these tubers, a study was conducted to determine the accumulation and diffusion of trichothecenes in potato tubers affected with dry rot caused by F. graminearum.
View Article and Find Full Text PDFFusarium head blight occurs worldwide in barley production, and the Fusarium mycotoxins, particularly deoxynivalenol (DON), have become a major concern for barley products, such as beer. This study investigated the content of bound DON in barley samples that were naturally infected with Fusarium head blight. Free DON was determined by gas chromatography-electron capture detection after standard acetonitrile:water extraction, while total DON was determined using treatment with trifluoroacetic acid.
View Article and Find Full Text PDFThe firming and carbohydrate fractions of concentrated starch gels supplemented with four alpha-amylases from different sources were evaluated. Correlations were found between the firmness data and results for the carbohydrate fractions extracted from the gels. The thermostable (TBA) and intermediate temperature stability (ISBA) bacterial alpha-amylases were most effective in decreasing the rate of firming.
View Article and Find Full Text PDFConcentrated starch gels were supplemented with four alpha-amylases from different sources. The retrogradation and recrystallization of the gels were evaluated using differential scanning calorimetry (DSC) and X-ray crystallography. Correlations between the retrogradation data and the carbohydrate fractions extracted from these gels were determined.
View Article and Find Full Text PDFAlong with food safety issues due to mycotoxins, the effects of Fusarium infections on malt and beer quality can be disastrous. While some of the Fusarium head blight mycotoxins, such as DON, present in infected barley may be lost during steeping, the Fusarium mold is still capable of growth and mycotoxin production during steeping, germination and kilning. Therefore, detoxification of grain before malting may not be practical unless further growth of the mold is also prevented.
View Article and Find Full Text PDFBarley yellow dwarf virus (BYDV) infection occurs frequently in barley in the Upper Midwest region of the United States; however, the impact of this disease on the yield and quality of malting cultivars has not been adequately addressed. Studies were conducted at Fargo, North Dakota (from 1989 to 1990) to determine the effect of BYDV infection on yield and malt quality parameters in barley. Three malting cultivars varying in yield potential and malting characteristics were artificially inoculated at the seedling stage with a North Dakota BYDV isolate of the PAV serotype.
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