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71.
ISABELLE DUFRESNE JAMES P. SMITH JIUN NI LIU ILSEMARIE TARTE BURKE BLANCHFIELD JOHN W. AUSTIN 《Journal of Food Safety》2000,20(4):251-268
Studies were done to determine the effect of film oxygen transmission rate (OTR) on the time to toxicity in vacuum packaged cold and hot smoked rainbow trout fillets challenged with C. botulinum type E (102 spores/g) and stored at refrigerated conditions (4C), and under mild (8C) and moderate (12C) temperature abuse conditions. While no samples were toxic at 4C, toxin was detected within 28 days at 8C for cold smoked trout fillets vacuum packaged in films with high OTR. Toxin was also detected for most vacuum packaged hot smoked trout fillets within 14–28 days at 8C, with the exception of trout fillets packaged in films with an OTR > 10,000 cc/m2 /day. In most cases at 8C, spoilage, based on odor/color scores, preceded or occurred simultaneously with toxigenesis. At 12C all cold and hot smoked trout were toxic after 14–21 days and samples packaged in films with an OTR <5000 cc/m2 /day became toxic before, or at the same time as, samples became spoiled. This study has shown that vacuum packaging of trout fillets in low gas barrier films, ranging in OTR from approximately 3,000 to approximately 10,000 cc/m2 /day at 24C and 0% relative humidity (RH), did not prevent the growth and toxin production by C. botulinum in vacuum packaged cold and hot smoked trout fillets at 12C. Additional barriers, other than the OTR of the packaging film, need to be considered to ensure the safety of vacuum packaged trout fillets, particularly at mild to moderate temperature abuse storage conditions. 相似文献
72.
Two α-amylase inhibitors from black bean (Phaseolus vulgaris) were purified to homogencity using ammonium sulfate fractionation, DEAE-Sephadex chromatography, phenyl-Sepharose hydrophobic interaction chromatography and gel filtration with Sephadex G-100. The inhibitors were designated I–1 and I–2 based on their order of elution from the phenyl-Sepharose column. Both inhibitors are mannose containing glycoproteins, composed of subunits; active against porcine pancreatic, human salivary, and insect α-amylases and inactive against bacterial, mold, and plant α-amylases. The inhibitors I-1 and I–2 have molecular weights of 49,000 and 47,000 and isoelectric points 4.93 and 4.86, respectively. Both inhibitors have similar amino acid compositions and are rich in aspartic acid, serine, glutamic acid, valine, and threonine and are low in sulfur containing amino acids. I–2 is more resistant to heat denaturation than I-1. 相似文献
73.
A procedure was developed to coat peanuts with aqueous whey protein isolate (WPI) solutions based on increasing coating-solution viscosity. Oxygen uptake of WPI-coated nuts and uncoated nuts were compared. WPI coatings delayed oxygen uptake of dry roasted peanuts at intermediate (53%) and low (21%) storage relative humidity. They had similar results at 29°C and 37°C. The effects of coating thickness and storage relative humidity indicate that the mechanism of protection of the coatings was through their oxygen barrier properties. 相似文献
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75.
JOHN J. CHIN 《Journal of Urban Affairs》2009,31(4):431-460
ABSTRACT: In addition to providing a wide range of essential services in local communities, service‐providing nonprofit organizations play an important role in shaping de facto local social policy through their participation in community‐based planning processes that guide or determine the distribution of federal funding for health and social services. This social policy role has become increasingly important in the United States as the federal government continues to privatize health and human services through providing grant funds to states and cities that are ultimately used to support local nonprofit health and social service organizations. The important role of service‐providing nonprofits in shaping local social policy has been understudied, as most studies on nonprofits and policy‐making focus on citizen advocacy organizations and their lobbying and protest activities, primarily at the national level. This study uses the case of the New York HIV Planning Council to address this gap in the literature, highlighting the benefits and pitfalls of an urban community planning process dominated by service providers from local nonprofit social service organizations whose own organizations are affected by the planning group's decisions. Factors that contributed to nonprofit providers' dominance as well as factors that limited their self‐interested behavior are reviewed. The relationship between the HIV nonprofit service system and the AIDS social movement is explored in light of theory on new social movements to help explain why nonprofit providers were sometimes able to promote attentiveness to the general public good while also advocating for their more self‐interested organizational needs. 相似文献
76.
KENNETH W. MILLER JUANELL N. BOYD JOHN G. BABISH DONALD J. LISK GILBERT S. STOEWSAND 《Journal of Food Safety》1983,5(3):131-143
Cabbage (Brassica oleracea var. capitata) was grown on soil (control) or municipal sewage sludge-treated plots. The cabbage was freeze-dried and analyzed for glucosinolate content and pattern. Results showed that cabbage grown on sludge-amended soil contained only half the glucosinolate content of cabbage grown on the control plot. The pattern of individual glucosinolates present was also altered. The sludge-grown cabbage glucosinolate extract was shown to be mutagenic in the non-activated test system of S. typhimurium TA 100. Extracts of both sludge-grown and control cabbage were shown to enhance the mutagenicity on a dose-response basis of aflatoxin B1 , benzo(a)pyrene, and captan. 相似文献
77.
78.
A water conserving cooling system with water recycle for blanched vegetables was designed to complement a previously developed water recycling blancher. The two stage cooler consisted of an evaporative cooling section with forced air and water sprays and a flume cooler with water, which was both refrigerated and recycled. A pilot scale blanching and cooling system was constructed, and broccoli spears were processed. The cooling system was effective at lowering the product temperature rapidly while maintaining the quality of the product at a high level as determined by ascorbic acid concentration, percentage of total solids, percentage of retained chlorophyll, and microbial counts. 相似文献
79.
JOHN J. PETROVIC 《Journal of the American Ceramic Society》1985,68(6):348-355
The mixed-mode fracture of hot-pressed Si3 N4 was investigated using inclined indentation surface flaws in bending and large crack geometries in combined tension/torsion. Non-coplanar fracture was observed in all cases. Values of KIc , KIIc , and KIIIc stress intensity factors were obtained, with ratios KIIc /KIc = 0.79 and KIIIc /KIc = 1.55 observed. For large cracks, mode II conditions had more of an effect on mode I fracture than mode III conditions. The mixed-mode I-II fracture of surface flaws was significantly different from that for large cracks, suggesting surface flaw shear resistance effects. A model describing these effects was derived, based on the ratio of the crack-opening displacement to the crack surface asperity height. 相似文献
80.