Induction of T Lymphocytes Specific for Bovine Viral Diarrhea Virus in Calves with Maternal Antibody

Passive antibody to bovine viral diarrhea virus (BVDV) acquired through colostrum intake may interfere with the development of a protective immune response by calves to this virus. The objective of this study was to determine if calves, with a high level of maternal antibody to bovine viral diarrhea virus (BVDV), develop CD4+, CD8+, or γδ T lymphocyte responses to BVDV in the absence of a measurable humoral immune response. Colostrum or milk replacer fed calves were challenged with virulent BVDV at 2-5 weeks of age and/or after maternal antibody had waned. Calves exposed to BVDV while passive antibody levels were high did not mount a measurable humoral immune response to BVDV. However, compared to nonexposed animals, these animals had CD4+, CD8+, and γδ T lymphocytes that were activated by BVDV after exposure to in vitro BVDV. The production of IFNγ by lymphocytes after in vitro BVDV exposure was also much greater in lymphocytes from calves exposed to BVDV in the presence of maternal antibody compared to the nonexposed calves. These data indicate that calves exposed to BVDV while maternal antibody levels are high can develop antigen specific CD4+, CD8+, and γδ T lymphocytes in the absence of an active antibody response. A manuscript presented separately demonstrates that the calves with T lymphocytes specific for BVDV in this study were also protected from virulent BVDV genotype 2 challenge after maternal antibody became undetectable

Influences of packaging attributes on consumer purchase decisions for fresh produce, Appetite 59

a b s t r a c t Packaging attributes are considered to have an influence on consumer purchase decisions for food and, as a consequence, also on its consumption. To improve the current minimal understanding of these influences for fresh produce, a survey instrument in the form of an online questionnaire has been developed and launched in the US. The first part of the questionnaire covers consumers' preferences for packaging convenience features, characteristics, materials, disposal method, and others for fresh produces in general, and the second focuses on attributes like price, container size, produce shelf life for a specific fresh produce, sweet cherries, to allow us to supply specific values for these factors to the participants. Cluster and conjoint analyses of responses from 292 participants reveal that specific packaging and produce attributes affect consumer purchase decisions of fresh produce in general and of sweet cherries in particular (P 6 0.05) and that some are population segment dependent (P 6 0.05). For produce packaging in general, 'extend the ''best by'' date' was ranked as the top convenience feature, the type of packaging material was considered to affect the food product quality (92.7%) and containers made from bio-based materials were highly appealing (3.52 out of 5.00). The most important attributes that affect the purchasing decisions of consumers regarding a specific fresh produce like sweet cherries are price (25%), shelf life (19%) and container size (17.2%)

Barrier Properties of Polymeric Packaging Materials to Major Aroma Volatiles in Herbs

This study determined the main transport coefficients (diffusion, solubility and permeability) of key aroma compounds present in tropical herbs (eucalyptol and estragol) through low‒density polyethylene (LDPE), polypropylene (PP), nylon (Nylon), polyethylene terephthalate (PET), metalized‒polyethylene terephthalate (MPET) and poly(lactic acid) (PLA) films at 15 and 25 °C. The concentration of aroma compounds permeating through the films were evaluated at various time intervals using a gas chromatograph flame ionization detector (GC–FID). Results showed that the diffusion coefficients of aroma compounds were highest in LDPE whereas the solubility coefficients were highest in PLA at both temperatures. PLA had the highest permeability coefficients for estragol at both temperatures. PP and LDPE had the highest permeability coefficients for eucalyptol at 15 and 25 °C, respectively. MPET had the lowest permeability for both aroma compounds studied. Aroma barrier properties can be used when selecting polymeric packaging materials to prevent aroma loss in various food and consumer products

Barrier Properties of Polymeric Packaging Materials to Major Aroma Volatiles in Herbs

This study determined the main transport coefficients (diffusion, solubility and permeability) of key aroma compounds present in tropical herbs (eucalyptol and estragol) through low‒density polyethylene (LDPE), polypropylene (PP), nylon (Nylon), polyethylene terephthalate (PET), metalized‒polyethylene terephthalate (MPET) and poly(lactic acid) (PLA) films at 15 and 25 °C. The concentration of aroma compounds permeating through the films were evaluated at various time intervals using a gas chromatograph flame ionization detector (GC–FID). Results showed that the diffusion coefficients of aroma compounds were highest in LDPE whereas the solubility coefficients were highest in PLA at both temperatures. PLA had the highest permeability coefficients for estragol at both temperatures. PP and LDPE had the highest permeability coefficients for eucalyptol at 15 and 25 °C, respectively. MPET had the lowest permeability for both aroma compounds studied. Aroma barrier properties can be used when selecting polymeric packaging materials to prevent aroma loss in various food and consumer products