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.

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.

Tyrophagus putrescentiae, known as the ham mite, is the most difficult pest to control in the dry-cured ham industry. Food-grade propylene glycol coated nets have been studied as an alternative to conventional mite infestation treatments but were heavy and costly to ship. This study aimed to increase the ease of use of the coated nets via drying. Three drying treatments: oven dried for 7 min (OD7m), oven dried for 20 min (OD20m), and counter dried for 24 h (CD24h), were tested to determine the efficacy at controlling mites as well as the mechanical properties of the nets and sensory characteristics of ham wrapped in the treated nets. The OD7m and CD24h treatments were effective at controlling mite growth in a laboratory setting. The drying treatments did not affect the mechanical properties, or the sensory characteristics of the hams wrapped with the dried net treatments.

Tyrophagus putrescentiae, (ham mite) is difficult for commercial dry cured ham producers to control. This research was conducted to test the efficacy of C8C9C10 fatty acids combined with and without food grade coatings to control mite infestations on dry cured hams. Ham cubes were coated directly or wrapped in nets saturated with combinations of xanthan gum (XG) or carrageenan (CG), propylene glycol alginate (PGA), and either propylene glycol or C8C9C10 fatty acid. The use of 10% C8C9C10 with XG and CG + PGA in direct coatings and 1% C8C9C10 with XG or 10% with both XG and CG/PGA in saturated nets inhibited mite population growth. Unexpectedly, the soybean oil solvent effectively controlled mite infestation. Sensory evaluation indicated that 10% C8C9C10 mixed with soybean oil and 100% soybean oil did not impart sensory differences to ham when used as a coating but did impact sensory attributes when used with nets.

The objective of this research was to evaluate if chitosan and another food-grade compound can be incorporated into food-grade coatings in conjunction with propylene glycol and polysaccharides to control Tyrophagus putrescentiae growth without affecting sensory attributes, water activity, and moisture content of dry-cured hams. Each coating solution was coated on ham cubes (2.5 × 2.5 × 2.5 cm3, n = 5/treatment) or infused in ham nets, and dry-cured ham cubes were wrapped in the ham nets prior to inoculation with 20 mixed-sex adult mites. Randomized complete block designs with two replications were utilized to evaluate the efficacy of treatments at controlling mite growth on dry-cured ham cubes. When CH was mixed with XG and infused into a net, fewer mites (15.7 and 21.0 mites) were on ham cubes (P < 0.05) in comparison to the control (211.2 mites). Results indicated that CH contributed to controlling mite growth since 1% XG alone did not control mite growth. Difference from control test results indicated that no sensory differences existed (NS) between CH-treated and control ham slices. The addition of a food-grade compound (SP or 24P) to the XG coatings enhanced mite control efficacy. When 1% SP was added to 1% XG, it effectively controlled mite growth in both coating and netting treatments. Increasing 1% SP to 2% SP did not significantly (NS) control mite growth in the coating solution but did control mite growth when infused in the net. Both coating and netting treatments with 2% 24P + 1% XG controlled mite growth. When 24P was the only ingredient in the treatment, both 1% and 2% 24P controlled mites when infused in the net. The addition of SP did not (NS) impact the sensory attributes of the dry-cured ham. The 2% 24P + 1% XG treatment differed in moistness (P < 0.05) when compared to the blind control, but the rating was still less than 2 (moderately different). Overall, results from these studies indicate that chitosan can potentially be added in coatings or ham nets as tools to control mites in an integrated pest management program for dry-cured hams.

En raison de leurs excellentes propriétés, les polyoléfines telles que le polypropylène et le polyéthylène sont largement utilisées dans des applications d'emballage alimentaire. Cependant, tout au long de leur cycle de vie ou de la première utilisation, les polyoléfines peuvent être exposées à des milieux contaminés qui limitent leur recyclabilité en contact alimentaire. Par conséquence, le recyclage de polyoléfines au contact alimentaire nécessite des niveaux de décontamination rigoureux et donc une technologie de décontamination avancée. L’objectif de ce travail consiste dans un premier temps à étudier la faisabilité et la potentialité de l’extraction par CO2 supercritique en mode batch pour la purification de polyoléfines (extraction d’additifs et de contaminants modèles). On s’est plus particulièrement attaché à étudier l’effet des paramètres du procédé sur la cinétique de l’extraction ainsi que l’influence de l’extraction supercritique sur les comportements rhéologique et thermique des matériaux purifiés. Dans un deuxième temps, on s’est intéressé au développement d’un nouveau procédé continu d’extraction par couplage de l’extraction supercritique et l’extrusion bi-vis. Les résultats les plus importants ont montré la potentialité de l’extraction par CO2 supercritique en mode batch pour la purification de polyoléfines sans influencer significativement les propriétés de la matrice / Due to their excellent properties, polyolefins such as polypropylene and polyethylene are widely used in food packaging applications to preserve and protect foodstuffs. However, throughout their lifecycle or first use, polyolefins can be exposed to contaminated media which limit their recyclability in food contact applications. Therefore, the recycling of polyolefins into direct food contact applications requires rigorous decontamination levels and thus effective and advanced recycling technology. The objective of this work is, at first hand, to study the feasibility and the potential of supercritical CO2 extraction in batch process for the purification of polyolefins (extraction of additives and model contaminants). In the whole, we investigated the effects of process parameters and contaminant structure on the extraction kinetic, and the influence of the supercritical CO2 extraction on the rheological and thermal behaviors of the purified materials. On the other hand, we aimed at the development of a novel continuous extraction process by coupling supercritical extraction technique and twin-screw extrusion. The most significant results showed the potential of supercritical CO2 extraction in batch mode for the purification of polyolefins without influence significantly the matrix properties