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Flue-cured tobacco (Nicotiana tabacum) has been managed to optimize the yield of high-quality cured leaf while maintaining nicotine levels within a relatively narrow range based on the Regional Minimum Standards Program. Among the 3,000 plus alkaloids found in tobacco, nicotine accounts for greater than 90% of the total alkaloids produced in commercial tobacco varieties. Precious research has demonstrated an association with nicotine levels and cured leaf yield and quality. On March 16, 2018, the Food and Drug Administration issued a notice for proposed rulemaking to limit nicotine in combustible cigarettes to 0.3-0.5 mg nicotine per gram of tobacco (an approx. 98% reduction from current levels). Studies on achieving decreased levels of nicotine in flue-cured tobacco have been conducted since the mid-1900's and some success has been found through breeding and genetics. The FDA proposal suggested changes to standard agronomic production practices as a means of achieving their proposed nicotine levels. The primary objectives of this work are: (1) evaluate the impact of standard agronomic production practices on nicotine levels and the resulting yield and cured leaf quality and (2) quantify differences in nitrogen-use efficiency between conventional and low-nicotine flue-cured tobacco varieties. Results showed that the changes to production practices did not sufficiently lower nicotine levels to the range proposed by the FDA. The only publicly available low-nicotine variety, LA FC53, did not achieve the targeted nicotine level and the yield and cured leaf quality was severely reduced. The study of nitrogen-use efficiency quantified differences between conventional and low-nicotine flue-cured tobacco varieties. Proprietary, low-nicotine varieties developed from K 326 tended to have lower nicotine levels than LA FC53 with improved yield and cured leaf quality. Both yield and quality are associated with nitrogen-use efficiency and the nitrogen-use efficiency of the new low-nicotine lines was comparable to K 326 and better than the previously developed, low-nicotine standard variety. No evaluation of smoking characteristics of the cured tobacco from these studies was conducted and would be necessary for commercial utilization of low-nicotine flue-cured tobacco. / Master of Science / Flue-cured tobacco (Nicotiana tabacum) has been managed to optimize the yield of high-quality cured leaf while maintaining nicotine levels within a relatively narrow range based on the Regional Minimum Standards Program. Among the 3,000 plus alkaloids found in tobacco, nicotine accounts for greater than 90% of the total alkaloids produced in commercial tobacco varieties. Precious research has demonstrated an association with nicotine levels and cured leaf yield and quality. On March 16, 2018, the Food and Drug Administration issued a notice for proposed rulemaking to limit nicotine in combustible cigarettes to 0.3-0.5 mg nicotine per gram of tobacco (an approx. 98% reduction from current levels). Studies on achieving decreased levels of nicotine in flue-cured tobacco have been conducted since the mid-1900's and some success has been found through breeding and genetics. The FDA proposal suggested changes to standard agronomic production practices as a means of achieving their proposed nicotine levels. The primary objectives of this work are: (1) evaluate the impact of standard agronomic production practices on nicotine levels and the resulting yield and cured leaf quality and (2) quantify differences in nitrogen-use efficiency between conventional and low-nicotine flue-cured tobacco varieties. Results showed that the changes to production practices did not sufficiently lower nicotine levels to the range proposed by the FDA. The only publicly available low-nicotine variety, LA FC53, did not achieve the targeted nicotine level and the yield and cured leaf quality was severely reduced. The study of nitrogen-use efficiency quantified differences between conventional and low-nicotine flue-cured tobacco varieties. Proprietary, low-nicotine varieties developed from K 326 tended to have lower nicotine levels than LA FC53 with improved yield and cured leaf quality. Both yield and quality are associated with nitrogen-use efficiency and the nitrogen-use efficiency of the new low-nicotine lines was comparable to K 326 and better than the previously developed, low-nicotine standard variety. No evaluation of smoking characteristics of the cured tobacco from these studies was conducted and would be necessary for commercial utilization of low-nicotine flue-cured tobacco.

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The main effects of lime, aluminium, iron and manganese were studied in field and greenhouse grown tobacco; relations between soil and plant measurements were examined. Ground limestone, ground mixed lime, ground dolomite and slaked lime at rates equivalent to 1,000 and 2,000 lb. CaC0₃/acre increased yield and quality of flue-cured tobacco both on Triassic and granite sands, whether applied early (February/March) or late (September); the highest rate and late application were often best. Yields increased with 4,000 and 6,000 lb. dolomite/acre applied late, but quality decreased when the pH was about 6.0. Lime did not affect leaf maturity as reflected by nitrogen and reducing sugars concentration . Where leaf discolouration (slate) occurred, the best quality and least discoloured leaf had the lowest manganese concentration and was grown on limed soil. On a very acid and probably nitrogen deficient soil, lime, borax and nitrogen (nitrate only tested) reduced the discolouration and improved the quality, but potassium sulphate increased discolouration and decreased quality. Calcium concentration in the leaf was increased by lime, particularly calcitic materials, and magnesium concentration was increased by dolomite. Lime also increased the filling value and petroleum ether extract, but decreased manganese, boron, chloride and sometimes potassium, and had no effect on phosphorus, nitrogen, aluminium, iron, crude fibre, nicotine, reducing sugars and equilibrium moisture. The inorganic composition of greenhouse plants was similar; generally gypsum increased calcium concentration more than calcium carbonate but it did not affect manganese concentration, which was decreased by calcium carbonate. In the stem and roots of field grown plants (dolomite only tested), the concentration of magnesium was increased but the concentrations of calcium, potassium, aluminium and iron were unaffected. Although the concentration of nitrogen was increased and that of phosphorus was decreased in the stem, these were unaffected in the roots. Aluminium and iron behaved differently to other nutrient ions, being more concentrated in the roots than aerial plant parts. Boron and magnesium deficiencies were observed in a dry and wet year, respectively, suggesting that variable mineral deficiencies can affect responses to lime. Initially soil pH was affected more by source of lime, but later mostly by rates. Slaked lime increased the soil pH more than did ground limestone, mixed lime or dolomite. In a glasshouse experiment, pH was more important than calcium supply and in the field, the largest yields were often associated with the highest pH. In pot experiments, aluminium drastically reduced yields in nutrient solution but not in soils, whereas iron was more severe in soils; manganese had little effect on yield. Manganese was readily taken up and translocated to the tops, but aluminium and iron were mainly concentrated in the roots, as was found in field grown plants. Iron decreased manganese concentration in all plant parts and aluminium decreased calcium and manganese in nutrient solution only. Although aluminium and iron generally increased the concentration of phosphorus in the roots, they did not interfere with phosphorus transport in the plant. Manganese caused the leaf to become chlorotic and when no iron was present the upper leaves became yellow, and developed brown and white lesions. However, in soil grown plants, sufficient iron was present in the soil solution to prevent break down of tissue. Yellowing of the upper leaves also occurred when plants were grown in nutrient solution with aluminium and no iron; when both were present, the plants were darker in colour. Although aluminium damaged roots in nutrient solution, high rates of iron severely damaged leaves of plants grown in soil. Since the concentrations of aluminium, iron and manganese were decreased in the soil solution by liming, they were compared with plant growth and composition in 17 different soils, with and without lime. As was expected, lime increased soil pH. It also increased exchangeable calcium, but decreased exchangeable aluminium, iron and manganese; exchangeable magnesium and potassium and resin extractable phosphorus were not affected. As the Ratio Law does not hold for all Rhodesian soils, anion adsorption will be avoided if the soils are equilibrated with O.OOOSM CaC1₂; the concentrations of the cations in solution were affected in the same way as exchangeable cations, but phosphorus was increased. There was no relationship between yield of tobacco and its chemical composition. The correlations between soil solution data and plant composition were poor, except for manganese and phosphorus; the relation between Mn ppm. in plant vsa (superscript)Mn/a (superscript)Ca + Mg (enclosed in square root sign √) in solution, and P% vs pH₂ P0₄ or pH₂ P0₄ +½ pCa, were both curvilinear. On the other hand, all measurements of exchangeable cations were poorly correlated with plant composition. Finally yield was poorly correlated with soil solution data, and pH was as satisfactory as any other measurement tested. Manganese toxicity was observed on three soils, and a probable manganese deficiency on one. It was not possible to define a limit above which manganese toxicity occurred, but manganese deficiency developed at about 63 ppm. manganese. Variations in pH and the availability of aluminium, iron and manganese occurred when soils were incubated at about field capacity, generally the main effects having developed within seven days. In all soils, there was an initial increase in soil pH and a maximum value was reached in one to four days, decreasing by variable amounts with longer periods of incubation. Although the concentration of aluminium was larger than that of iron, the relation between both ions and soil pH was curvilinear, their concentrations increasing with decreasing pH. Increased temperature of incubation increased pH with a resultant decrease in the concentration of aluminium, but in one soil it appreciably increased the availability of iron in the early periods of incubation. Autumn and spring ploughing did not affect subsequent pH or the concentration of aluminium and iron in the soil solution. Manganese concentration varied from soil to soil and was not related to soil pH. In most soils there was a decrease in manganese concentration with length of incubation and it decreased more rapidly the lower the initial concentration. Temperature effects were variable and moisture affected the behaviour of manganese more than temperature. These findings and the distribution of aluminium, iron and manganese in the plant helped to explain the poor correlations.

Sweden has experienced a surge in retail labels within the food industry the last decade and this increase has meant great changes within the meat industry. Producer brands have been faced with issues of strategy formulation and changing power structures that has affected small-and medium sized companies more than others. The purpose of this thesis is to, from a small- and medium sized producer perspective; investigate the impact the increase in retail label products have on selected producer brand producing companies in the Swedish meat industry and if they constitute a major threat to the producer brands. Furthermore, the thesis addresses issues such as the present structure of the industry and future views of the meat industry. Method A qualitative research method was used in order to investigate the impact of the increase in retail labels. Interviews were conducted with three cured meat producers operating in the region of Småland. Furthermore, a market leading producer and representatives from the market leading retailer was also included in the study to gain a deeper understanding of market conditions. Results The results of the interviews shows an industry that is mature and experiencing slow and sometimes even declining growth where companies are pretty much set in their ways. The fiercest competition, over shelf space, is between producers with similar strategies instead of between producers and retailers. The increase in retail labels has meant a drastically reduced shelf space for producers to compete over. However, the three producers have taken steps in order to secure that the threat from retail labels is kept at a minimum. Nevertheless, new retail labels that will be closer to producer brands in terms of quality and price are coming. These are seen as a greater threat than the existing labels.

<p>Sweden has experienced a surge in retail labels within the food industry the last decade and this increase has meant great changes within the meat industry. Producer brands have been faced with issues of strategy formulation and changing power structures that has affected small-and medium sized companies more than others. The purpose of this thesis is to, from a small- and medium sized producer perspective; investigate the impact the increase in retail label products have on selected producer brand producing companies in the Swedish meat industry and if they constitute a major threat to the producer brands. Furthermore, the thesis addresses issues such as the present structure of the industry and future views of the meat industry.</p><p>Method</p><p>A qualitative research method was used in order to investigate the impact of the increase in retail labels. Interviews were conducted with three cured meat producers operating in the region of Småland. Furthermore, a market leading producer and representatives from the market leading retailer was also included in the study to gain a deeper understanding of market conditions.</p><p>Results</p><p>The results of the interviews shows an industry that is mature and experiencing slow and sometimes even declining growth where companies are pretty much set in their ways. The fiercest competition, over shelf space, is between producers with similar strategies instead of between producers and retailers. The increase in retail labels has meant a drastically reduced shelf space for producers to compete over. However, the three producers have taken steps in order to secure that the threat from retail labels is kept at a minimum. Nevertheless, new retail labels that will be closer to producer brands in terms of quality and price are coming. These are seen as a greater threat than the existing labels.</p>

Dry-cured hams often become infested with ham mites (Tyrophagus putrescentiae) during the aging process. Methyl bromide has been used to fumigate dry cured ham processing plants and is the only known fumigant that is effective at controlling ham mite infestations. However, methyl bromide will be phased out of all industries by 2015. This research was designed to 1) determine the efficacy of phosphine fumigation at controlling ham mites and red-legged beetles and its impact on the sensory quality and safety of dry cured hams, and 2) to develop and evaluate the potential of using food-grade film coatings to control mite infestations without affecting the aging process or sensory properties of dry-cured hams. Fumigation trials were conducted in simulated ham aging houses and commercial ham aging houses. Mite postembryonic mortality was 99.8% in the simulated aging houses and >99.9% in commercial aging houses two weeks post fumigation. Sensory tests with trained panelists indicated that there were no detectable differences (P>0.05) between phosphine fumigated and control hams. An analytical method was developed to determine phosphine concentration in ham. In addition, residual phosphine concentration was below the legal limit of 0.01 ppm in ham slices taken from phosphine fumigated hams. Coating trials were conducted on ham cubes and slices. Cubes coated with xanthan gum+20% propylene glycol and carrageenan/propylene glycol alginate+10% propylene glycol were effective at controlling mite infestations under laboratory conditions. Barrier properties (water vapor permeability and oxygen permeability) were measured to estimate the impact of coatings during the aging process. It was evident that carrageenan/propylene glycol alginate were permeable to moisture and therefore could potentially be applied to the hams during the aging process.

Since methyl bromide is an ozone depleting substance, there is a significant need to find effective alternative compounds to control mite infestations on dry cured hams. Therefore, the objective of this study was to determine the most effective relative humidity and/or temperature to minimize mite reproduction and mold growth on dry cured hams in untreated and food grade ingredient infused nets. Mites on ham slices in untreated nets were reduced from the initial inoculum level of 50 mites per ham slice when exposed to 85% RH at 24, 28, and 32°C. Results indicated that hams should be stored at 85% RH or greater to minimize mite reproduction when xanthan gum and propylene glycol infused nets are used. Nets infused with carrageenan, propylene glycol alginate, and propylene glycol, completely inhibited mite reproduction at 85% RH and were effective at controlling mold growth.

Distillate solutions that were derived from concentrated ferment were incorporated into either a carrageenan (CG) and propylene glycol alginate (PGA) gum blend or into a CG, PGA, and xanthan gum (XG) blend. Distillate treatments were compared against a 10% propylene glycol treatment, a gum only control, and negative control using three hams that were cut into 2.5 cm thick slices and then cut into 2.5×2.5×2.5cm cubes (n=50) that were dipped into solutions prior to conducting mite bioassays. Coated and control ham cubes were inoculated with 20 adult mites from the species T. putrescentiae (Schrank), and incubated for 2 and 3 weeks. The distilled treatments with CG + PGA + XG had a greater reduction (P<0.05) in mite populations than all other treatments with the exception of the 10% PG coated treatments. In addition, there were no differences between treatments with respect to sensory texture, flavor, and moistness.