The goal of this study was to determine how enteric viruses persist within shellfish tissues. Several lines of novel evidence show that phagocytic blood cells (hemocytes) of Eastern oysters (Crassostrea virginica) play an important role in the retention of virus particles. Our results demonstrated an association of virus contamination with hemocytes but not with hemolymph. Live oysters contaminated overnight with hepatitis A virus (HAV) and murine norovirus (MNV) had 56% and 80% of extractable virus associated with hemocytes, respectively. Transfer of HAV-contaminated hemocytes to naïve (virus-free) oysters resulted in naïve oyster meat testing HAV positive for up to 3 weeks. Acid tolerance of HAV, MNV, poliovirus (PV), and feline calicivirus (FCV) correlated with the ability of each virus to persist within oysters. Using reverse transcription-PCR (RT-PCR) to evaluate persistence of these viruses in oysters, we showed that HAV persisted the longest (>21 days) and was most acid resistant, MNV and PV were less tolerant of acidic pH, persisting for up to 12 days and 1 day, respectively, and FCV did not persist (<1 day) within oysters and was not acid tolerant. This suggests that the ability of a virus to tolerate the acidic conditions typical of phagolysosomal vesicles within hemocytes plays a role in determining virus persistence in shellfish. Evaluating oyster and hemocyte homogenates and live contaminated oysters as a prelude to developing improved viral RNA extraction methods, we found that viruses were extracted more expediently from hemocytes than from whole shellfish tissues and gave similar RT-PCR detection sensitivities.

The purpose of the study was to determine the effect of high-hydrostatic pressure (HHP) on inactivation of human norovirus (HuNoV) in oysters and to evaluate organoleptic characteristics of oysters treated at pressure levels required for HuNoV inactivation. Genogroup I.1 (GI.1) or Genogroup II.4 (GII.4) HuNoV was inoculated into oysters and treated at 300 to 600 MPa at 25 and 0 °C for 2 min. After HHP, viral particles were extracted by porcine gastric mucin-conjugated magnetic beads (PGM-MBs) and viral RNA was quantified by real-time RT-PCR. Lower initial temperature (0 °C) significantly enhanced HHP inactivation of HuNoV compared to ambient temperature (25 °C; P < 0.05). HHP at 350 and 500 MPa at 0 °C could achieve more than 4 log10 reduction of GII.4 and GI.1 HuNoV in oysters, respectively. HHP treatments did not significantly change color or texture of oyster tissue. A 1- to 5-scale hedonic sensory evaluation on appearance, aroma, color, and overall acceptability showed that pressure-treated oysters received significantly higher quality scores than the untreated control (P < 0.05). Elevated pressure levels at 450 and 500 MPa did not significantly affect scores compared to 300 MPa at 0 °C, indicating increasing pressure level did not affect sensory acceptability of oysters. Oysters treated at 0 °C had slightly lower acceptability than the group treated at room temperature on day 1 (P < 0.05), but after 1 wk storage, no significant difference in sensory attributes and consumer desirability was observed (P > 0.05).

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The present experiment was conducted to measure the extent and nature of quality loss in farmed steelhead fillets during frozen storage, to determine the possible causes of steelhead pigment fading as a result of frozen storage and to suggest some methods for improving storage conditions in order to obtain good‐quality frozen steelhead. This two‐part study confirms the importance of frozen temperature and appropriate storage conditions on the extension of product shelf life. The fading phenomenon of steelhead fillets during 10 months of frozen storage at −20C was subsequently studied in detail over a 6‐week period for fillets stored at both −5 and −30C. Associated protein denaturation, tough/dry texture and rancidity were also examined. Temperature had a stronger effect on the development of rancidity in steelhead fillets than the duration of the storage period for fillets stored for up to 6 weeks. Highest levels of oxidation products were observed in the fillets stored at −5C even in the short‐term storage experiment while extensive lipid oxidation, toughening, expressible fluid loss on thawed fillets and apparent pigment fading took place during long‐term storage at −20C. The results from sensory evaluation of texture, color and flavor agreed well with the chemical assessment of rancidity. Flavor scores from the fillets stored at −5C revealed a slightly oily/rancid taste as compared to the samples at −30C after 6 weeks of storage. The expressible fluid results indicated that the binding of water to protein decreased significantly in fillets stored at −5C as compared to the matching fillets at −30C and during long‐term storage at −20C. The increases in expressible fluid correlated positively with fading (L*) and negatively with redness (a*). The quantity of extractable protein nitrogen (EPN) decreased drastically over the 6‐week period in both temperature groups (−5 and −30C), but during this relatively short experiment, the EPN levels between temperature treatments were not significantly different. In both experiments, fillet redness faded dramatically as a result of frozen storage. Abusive cold storage at −5C resulted in far more fading than at −30C even after 6 weeks. Fading was measured both subjectively and objectively using reflectance colorimetry, and an increase in whiteness value was concomitant with a decrease in redness. It is suggested that whiteness may be used as an accurate subjective parameter for color fading in frozen storage. Redness values were significantly higher in the fillets at −30C. The study showed that pigment fading was not a result of a decrease in carotenoid concentration but may be related to protein denaturation, which causes muscle tissue appearance to change from translucent to opaque, thereby giving the illusion of pigment fading.

Given the high unit value of live American lobsters (Homarus americanus), a non‐destructive field method to assess physiological state is desirable during out‐of‐water transport conditions. This study compared an Uricon® specific gravity refractometer, with a commercial veterinary blood analyser (Vet‐Test), as a method for determining the blood total protein concentration in live, out‐of‐water individuals. Regression analysis of R2 = 0.8641 (n = 64) was observed in determination of blood total protein concentration, y = 0.0036x + 1.0163 where x is the protein concentration in mg dL−1 in Vet‐Test. Our results (R2 = 0.864, SE ± 0.003) support the results (R2 = 0.985) of the previous study conducted by Leavitt & Bayer (1977) in which serum total protein was compared with the refractometric method. We therefore confirm that the refractometric method can be used as a reliable method to indicate health of a lobster by measuring the blood total protein concentration. The results show good correlation between the protein concentrations observed using the refractometric method and a Vet‐Test blood chemistry analyser. anova analysis was significant between the protein refractometer and the Vet‐Test (P < 0.05). Although protein concentration units obtained from both methods were different the results followed the same trends. Refractometry as a method is reliable to determine blood total protein concentrations in the American lobster. Consequently, a refractometric method can be used directly by commercial growers and distributors to assess responses to holding facility conditions and to feeding regimes. Whole blood protein concentrations may provide more information than serum protein concentrations as measured in the study of Leavitt & Bayer (1977).

The world's population continues to increase at record rates along with corresponding nutritional needs and related agricultural consequences. In the United States, food waste levels serve as dominant components of landfill masses, oil and freshwater waste, methane and CO 2 emissions, damage to wildlife ecosystems, and substantial financial losses. Agricultural effects on the environment were investigated through various research studies, referenced in this document, and efforts made toward food waste recycling were discussed as noteworthy models concerning improvements in sustainable agricultural practices. Food waste levels in the United States can be traced as faults of consumers, agricultural businesses, as well as federal legislation and there is an evident need for reform to maintain consumer health, viable foreign affairs, and environmental sustainability. Present agricultural practices are intense and rapid, increasing the risk of soil infertility and commercial alterations in production yields; repercussions well documented in neighboring nations. Experts argue that food waste in developed countries damages food availability around the world and, based on current agricultural practices and production, there is debate concerning the earth's sustainability of the human population in coming generations. This article delineates the extent to which food waste in the United States serves as an integral factor toward environmental instability on a global scale with emphasis on the critical capacity of public reception of the content discussed herein.

Eastern oyster, Crassostrea virginica is a keystone species in many estuarine bays. They clean the water by filtering out suspended particulates from the water column, while their reefs serve as valuable habitat for many ecologically and economically important macrofaunal species. However, with the ever-increasing development along our coastlines, the oyster population throughout the Mid-Atlantic region has plummeted as a result of overharvesting, extreme eutrophication, and disease. In response to this detrimental decline, many conservation organizations in the area have developed communityinvolvement programs commonly referred to as 'oyster gardening' to help restore the oyster population, while instilling within the community a strong sense of stewardship for their bays. Although the oyster gardening program in Delaware is relatively new, its popularity has grown tremendously. It is the hope of many Delaware residents that the reintegration of oysters into the Inland Bays will help to return their bays to the state of health in which they once were. Despite the expansion, further development of designated reef area is necessary to ensure the successful proliferation of C. virginica in Delaware's Inland Bays.