Use of nets treated with food-grade coatings on dry-cured ham to control Tyrophagus putrescentiae infestations without impacting sensory properties

Dry-cured hams may become infested with the ham mite Tyrophagus putrescentiae during aging. Food-grade coatings have been developed to control mite infestations as a potential alternative to replace methyl bromide, but dipping or spraying these coatings requires additional labor and processing steps. Nets composed of polyester, a polyester/cotton blend and cotton were infused with coatings that consisted of propylene glycol, and either propylene glycol alginate and carrageenan or xanthan gum. Results indicated that the polyester/cotton blend and cotton nets that contained propylene glycol were effective at controlling mite infestations in assays with ham cubes covered in nets. The polyester nets slowed mite growth but were not effective at controlling mite reproduction due to low absorbance of the coatings. Polyester/cotton blend nets treated with coatings on whole hams were not different from control hams with respect to flavor, texture and moistness. Mite infestation tests on whole hams indicated that coated nets with greater stitch densities were effective at controlling mite growth. Future research will include the optimization of coating formulations and scaled-up testing in dry-cured ham plants.     

Effects of temperature,relative humidity,and protective netting on Tyrophagus putrescentiae (Schrank) (Sarcoptiformes: Acaridae) infestation,fungal growth,and product quality of dry cured hams

Since methyl bromide is an ozone depleting substance, there is a need to find effective alternative methods 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 combination to minimize mite reproduction and mold growth on dry cured hams in untreated and food-grade ingredient infused nets. Food grade coating formulations of 1) xanthan gum and propylene glycol, and 2) carrageenan, propylene glycol alginate, and propylene glycol nets were infused into nets. Dry cured ham cubes and slices were wrapped with untreated and treated nets, inoculated with 20 large mixed-sex mites per cube or 50 large mixed-sex mites per slice, and then stored for 14 d at each temperature (24, 28, and 32 °C) and RH (55, 65, 75, and 85%) combination in an environmental chamber. Tyrophagus putrescentiae on ham slices in untreated nets were reduced from the initial inoculum level of 50 mites per ham slice when exposed to 85% r.h. at 24, 28, and 32 °C. Nets infused with xanthan gum and propylene glycol or carrageenan, propylene glycol alginate, and propylene glycol, completely inhibited mite reproduction at 85% r.h. In addition, the nets infused with carrageenan, propylene glycol alginate, and propylene glycol, controlled mite reproduction below the initial inoculum level on ham cubes and ham slices at all temperatures and relative humidities that were evaluated. Six to eight trained panelists rated the amount of mold on the ham slice surfaces on a 0–100% scale and both treated nets evaluated were effective at preventing mold growth on the ham slices.     

Sampling methods to detect and estimate populations of Tyrophagus putrescentiae (Schrank) (Sarcoptiformes: Acaridae) infesting dry-cured hams

Spatial and temporal dynamics of pest populations are an important aspect of effective pest management. However, absolute sampling of some pest populations such as the ham mite, Tyrophagus putrescentiae (Schrank) (Sarcoptiformes: Acaridae), a serious pest of dry-cured ham, can be difficult. In this study sampling methods were compared and sampling plans were developed for the ham mite. In one experiment, the number of food-baited traps was maintained at four and the number of mites varied from 500 to 10,000 individuals in environmentally-controlled 18-m² rooms. The number of mites captured in traps increased linearly as the number of mites released increased. Experiments conducted in simulated ham aging rooms suggested that mites preferred the proximal (closer to the pig's body) to the distal side of the ham. The number of mites captured in traps also varied with trap location relative to hams hung from shelves. There were varying degrees of relationships between the number of mites captured in traps and the sampling methods used, such as counts of mites from the storage rack, vacuum sampling of the floor, and ham sampling. Relationships between absolute counts of mites and the number of mites captured in traps or on specific areas of ham were both moderately strong and significant. Two sampling plans were developed for the mite, and it was determined that an economic threshold close to 1 mite per sample unit on the ham can be estimated with 21 and 40 samples at precision levels of 0.35 and 0.25, respectively, or with 10 ham samples when classifying the mite's infestation level as being above or below an action threshold of 0.43. These sampling plans for the ham mite can facilitate the development and evaluation of cost-effective integrated pest management interventions.     

The application of food grade short chain fatty acids to prevent infestation of Tyrophagus putrescentiae on dry cured ham and the effects on sensory properties

Tyrophagus putrescentiae (ham mite) is difficult for commercial dry cured ham producers to control. Methyl bromide is an effective fumigant but is now banned as an ozone depleting substance, meaning alternative methods to control mite infestation must be found. 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 C₈C₉C₁₀ with combinations of either soybean oil, xanthan gum (XG) or carrageenan (CG) + propylene glycol alginate (PGA). Cubes were then inoculated with 20 large mixed sex ham mites and stored for 14 days at 22 ± 2 °C and 70 ± 5% relative humidity. The soybean oil alone or in combination with 10% C₈C₉C₁₀ in direct coating, and 1% and 10% C₈C₉C₁₀ in coated nets controlled mite population growth. In addition, the use of 10% C₈C₉C₁₀ + XG and 10% C₈C₉C₁₀ + CG + PGA in direct coatings or in saturated nets, and 1% C₈C₉C₁₀ + XG in saturated nets also inhibited mite population growth. Unexpectedly, the soybean oil solvent by itself effectively controlled mite population growth as well. Sensory evaluation was performed using a difference from control test (n = 8) and indicated that only 10% C₈C₉C₁₀ mixed with soybean oil and 100% soybean oil did not impart sensory differences to ham when used as a coating. However, for ham slices treated in saturated nets and gum with C₈C₉C₁₀ mixtures in either coating or saturated nets did impart sensory differences. Results indicated that C₈C₉C₁₀ and soybean oil could be used in coating formulations to control ham mites but long-term testing, sensory evaluation, and scaled up testing is needed prior to industrial implementation.     

A review of alternatives to organophosphorus compounds for the control of storage mites

This literature review aims to identify potential alternatives to the use of organophosphorus pesticides for the control of mite pests in stored commodities. Substances including insect growth regulators, inert dusts, botanicals, pyrethroids and other novel materials are discussed with emphasis on their efficacy against important storage mite pests. Their modes of action, together with the advantages and disadvantages of their use within a storage environment, are reviewed including cited efficacy against storage insects. Inert dusts meet criteria required for a product to be an effective replacement for OPs, and may offer the greatest potential. The future of any alternative lies in its ability to be incorporated into an integrated pest management programme.     

Biology and management of Plodia interpunctella (Lepidoptera: Pyralidae) in stored products

Plodia interpunctella (Hübner), the Indian meal moth, is a world-wide insect pest of stored-products and processed food commodities. It can infest a variety of products and is perhaps the most economically important insect pest of processed food. In this review, we summarize the biology of P. interpunctella, discuss oviposition and development in relation to temperature, environment and food source, examine studies involving sampling and detection, describe various aspects of integrated control, summarize the current knowledge regarding management of P. interpunctella, and address potential areas for new research. The use of reduced-risk insecticides, non-chemical control, targeted pest management through spatial analysis and other means of identifying specific locations of infestations, and computer models that simulate population growth, are examples of some of those new areas of research.     

The application of chitosan in food-grade coatings to control Tyrophagus putrescentiae on dry-cured hams and the effects on sensory properties

The objective of this research was to evaluate if chitosan-containing food-grade coatings can control Tyrophagus putrescentiae growth without affecting the sensory attributes of dry-cured hams. Food-grade coating treatments included (1) 0.3% chitosan (CH), (2) 0.6% CH, (3) 0.3% CH + 10% propylene glycol (PG), (4) 0.3% CH + 1% xanthan gum (XG), (5) 0.3% CH + 1% XG + 10% PG, (6) 0.3% CH + 1% carrageenan (CG) + 1% propylene glycol alginate (PGA), and (7) 0.3% CH + 1% CG + 1% PGA + 10% PG. Each coating solution was coated on ham cubes (2.54 × 2.54 × 2.54 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 adult mites. A randomized complete block design with three replications was utilized to evaluate the efficacy of treatments at controlling mite growth on dry-cured ham. When CH was mixed with XG (0.3% CH + 10% PG + 1% XG, and 0.3% CH + 1% XG) and infused into a net, fewer mites (15.7 and 21.0 mites) were on the ham cubes (P < 0.05) in comparison to the control (211.2 mites). Results indicate that CH has the efficacy to control mites 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 chitosan coated nets helped control mite growth when used in conjunction with xanthan gum and propylene glycol and collectively may be useable as part of an integrated pest management plan for ham producers to control mites in their aging houses. Therefore, these coating solutions could be scaled up to evaluate their efficacy in ham aging houses.     

Biology and management of the red-legged ham beetle,Necrobia rufipes DeGeer (Coleoptera: Cleridae)

The red-legged ham beetle, Necrobia rufipes DeGeer (Coleoptera: Cleridae), is an important world-wide insect pest of stored-products of animal origin, but it can also infest a wider range of commodities. A review detailing the biology of N. rufipes including the morphology, development and reproduction of this pest is presented. This review also illustrates various aspects of its integrated control and summarizes the current knowledge for N. rufipes management, given that there were additional data that have been produced towards this direction during the last decade. Furthermore, this paper identifies potential areas of further research on N. rufipes for practical implementation.     

Inhibition of Listeria monocytogenes using natural antimicrobials in no-nitrate-or-nitrite-added ham

Consumer demand for foods manufactured without the direct addition of chemical preservatives, such as sodium nitrite and organic acid salts, has resulted in a unique class of "naturally" cured meat products. Formulation with a natural nitrate source and nitrate-reducing bacteria results in naturally cured processed meats that possess traits similar to conventionally cured meats. However, previous research has shown that the naturally cured products are more susceptible to pathogen growth. This study evaluated Listeria monocytogenes growth on ham manufactured with natural curing methods and with commercially available clean-label antimicrobials (cultured sugar and vinegar blend; lemon, cherry, and vinegar powder blend) and assessed impacts on physicochemical characteristics of the product. Hams made with either of the antimicrobials supported L. monocytogenes growth similar to that in the traditionally cured control (P > 0.05). Hams made with prefermented celery juice powder had the lowest residual nitrite concentrations (P < 0.05), and when no antimicrobial was added, L. monocytogenes growth was similar to that of the uncured control (P > 0.05). Aside from residual nitrite and nitrate concentrations, few physicochemical differences were identified. These findings show that ham can be produced with natural curing methods and antimicrobials to provide similar L. monocytogenes inhibition and physicochemical traits as in traditionally cured ham.     

Biology, behaviour and environmentally sustainable control of Tineola bisselliella (Hummel) (Lepidoptera: Tineidae)

This review summarises the information available on the biology, behaviour and economic significance of the common or webbing clothes moth, Tineola bisselliella (Hummel), currently the most important and widespread clothes moth pest throughout the world. These moths can cause the loss of irreplacable material of aesthetic, historic and scientific importance, as well as damaging every-day items such as clothes, furnishings and other materials prepared from animal fur, wool, feathers and hides. Methods for the detection and control of this pest are outlined, with particular emphasis on control strategies that are environmentally sustainable and avoid the use of conventional pesticides and fumigants. Improvements in storage coupled with targeted use of appropriate control measures will help to reduce pest populations. However, the continuing problems with this pest highlight the need for improved methods of detection, prevention and management.     

我国烟草苗床甲基溴替代研究现状及展望

溴甲烷是一种高效、广谱的土壤熏蒸剂,在我国烟草苗床上广泛使用,由于显著消耗臭氧层,需要寻找有效替代技术。本文综述了国内外甲基溴替代技术研究现状,对我国烟草苗床替代技术进行了分析,并对我国育苗过程中存在的问题作了探讨,提出通过育苗技术和苗床害物IPM策略结合,可望有效替代甲基溴,实现良好的社会、生态和经济效益。      

Life tables and a physiologically based model application to Corcyra cephalonica (Stainton) populations

The rice moth Corcyra cephalonica is a harmful insect pest for grains stocked in storage systems. Its infestations represent a serious concern among producers, because of the non-marketability of the products affected by it and subsequent economic losses.New technologies are improving the supply chain of the stored grains, in line with the integrated pest management framework. However, a prompt control action also requires an in-depth knowledge of insect pests’ biology and their response to environmental parameters. If this information is available, it can also be translated into mathematical language. The modelling of insect pest populations is increasing in utility, particularly if the models are included in decision support systems.The aim of this work concerns two aspects of a model application and validation. Since physiologically based models require information about interactions between species and environment, C. cephalonica individuals were reared at different constant temperatures: 18, 21, 24,26, 28, 30,34 and 36 °C. This first part provided the life tables, whose data were used to estimate the parameters of the Logan, Briére, and Sharpe and De Michele development rate functions.The second part of the work concerns the application of a physiologically based model described by a first order partial differential equation. The validation of the simulations was conducted with a semi-field experimentation with three repetitions.Results showed that the life tables are well represented by the Sharpe and De Michele development rate function, and that the physiologically based model proposed is reliable in representing field populations.     

Zn-porphyrin formation in cured meat products: Effect of added salt and nitrite

Zn-porphyrin (Zn-pp) was quantified by fluorescence spectroscopy in the cured and dry cured meat products: Parma ham, Iberian ham, dry-cured ham with added nitrite, cooked ham with added nitrite, raw ham meat, raw bacon and Karree-Speck. The highest amount of Zn-pp was found in dry-cured Parma ham and Iberian ham, while the use of nitrite as curing agent was found to inhibit completely the formation of Zn-pp in meat products. A positive correlation between both Zn content and Fe content and the logarithmic transformed Zn-pp content (measured as fluorescence intensity I_fl) was found for the different cured and dry cured meat products, with correlation coefficients of 0.79 (p < 0.001) and 0.71 (p < 0.01), respectively. Log I_fl correlates best with the Zn content, indicating that the formation of Zn-pp is proportional to the Zn content. A model system with vacuum packed pork in brine with different added levels of sodium chloride with or without nitrite and Zn acetate was investigated in order to further elucidate the mechanism of Zn-pp formation. Zn-pp increased with time (up to 42 days investigated) in non-cured meat and for meat cured solely with NaCl lower than 9%. Addition of nitrite or Zn(II) in the curing brine was found to inhibit formation of Zn-pp confirming the observations from the various cured meat products. It is suggested that a chloride anion assisted dissociation of iron from myoglobin could be rate-determining for Zn-pp formation in meat products.     

干腌火腿中的螨

干腌火腿中的螨主要是腐食酪螨和长食酪螨。改变制作过程中的温度和相对湿度对控制干腌火腿中的螨的作用不大,也会降低干腌火腿的品质。几种天然单萜类化合物对于控制干腌火腿中的螨具有很好的应用前景。     

“牛干巴”质量标准探讨

研究了云南爱伲＂牛干巴＂的理化指标,结合分析腊肉、火腿等腌腊肉制品的相关质量标准及其依据,提出了科学合理的＂牛干巴＂企业标准的理化指标。     

Potential for widespread application of biological control of stored-product pests—the European perspective

“Biological control of stored product pests has substantial potential in Europe”. This is essentially the conclusion of the activities of a European working group funded by the COST system, an intergovernmental networking system. Working group 4 of COST action 842 (2000-2005) focussed on biological control of stored-product pests and has considered a number of existing and potential fields for application of biological control. Three situations were identified where biological control would be a valuable component of integrated pest management: (1) Empty room treatment against stored-product mites, beetles and moths; (2) Preventative treatment of bulk commodities against weevils (Sitophilus spp.) and storage mites; (3) Preventative application of egg-parasitoids against moths in packaged products. Development of methods for biological control and of mass production of natural enemies for these situations will contribute to ensuring that stored food products are protected from insect and mite pests using techniques that are safe for consumers, workers and the environment.     

Grain protectants: Current status and prospects for the future

Since the 1960s grain protectants have been used as a primary means of insect pest management in bulk storages, especially in countries which store large amounts of grain for domestic food production and export trade. With the increasing costs of development and registration of insecticides, the number of available protectants has begun to decrease, a trend that will no doubt continue. Furthermore, there are several biological, economic and sociological influences that are causing a gradual shift from chemical-based pest management to integrated pest management utilizing computer-based decision support systems. This paper will discuss several factors in terms of their potential impact on the use of conventional grain protectants, including insecticide residues and consumer perceptions, resistance to protectants in major pest species, the direct and indirect costs of insecticides, development and registration of biopesticides, inert dusts, new technologies for fumigation and controlled atmosphere treatments, the expanded use of aeration in management programs, biological controls, and the development of expert systems. In this paper the term ‘grain protectants’ will be used to refer to only organophosphorus, pyrethroid, or carbamate insecticides that are applied directly to grain for residual control.     

ACCELERATED DRY CURING OF PORK LEGS (HAMS): A REVIEW

Dry curing of pork legs produces a product with unique flavor. However, the process is labor intensive and time consuming and is partially responsible for dry cured ham being less competitive in the marketing arena. Dry curing can be accelerated through production techniques such as tumbling, blade tenderizing, microbial inoculation, use of nitric oxide and processing as skinned and/or boneless legs. These techniques are discussed and the major benefits and limitations are noted. Although these processes can accelerate dry curing, more research is needed to determine the optimal conditions needed to expedite the dry curing process and ensure color uniformity and stability, aged ham flavor and sufficient weight loss to conform to regulatory requirements.     

Sulfuryl fluoride as a methyl bromide alternative for fumigation of Necrobia rufipes (Coleoptera: Cleridae) and Tyrophagus putrescentiae (Sarcoptiformes: Acaridae), major pests of animal-based stored products

Sulfuryl fluoride (SF) has been registered in many countries for stored product applications as an alternative to other fumigants, especially methyl bromide (MB). Research was conducted to establish SF fumigation protocols for the mortality of pests infesting post-harvest durable commodities. The efficacy of SF against two major arthropod pests of southern dry-cured hams, the red-legged ham beetle, Necrobia rufipes, and the ham mite, Tyrophagus putrescentiae, was investigated. SF caused significant mortality in ham beetles but not for ham mites when treated for 48 h at 23 °C. Eggs of N. rufipes were more tolerant to SF than other stages fumigated. In addition, early aged (1–2 d old) eggs of N. rufipes were more susceptible to SF than late-aged (4–5 d old) eggs. Furthermore, SF fumigation led to 100% control of larvae, pupae and adults of N. rufipes by 8 g/m³ while the eggs required 20.88–24.72 g/m³ to prevent 100% hatch. However, T. putrescentiae showed high tolerance to SF as it survived concentration-time products in excess of the standard label limit 1500 g h/m³. SF studies also revealed that the eggs of T. putrescentiae were several fold more tolerant than that of the mobile stage, the nymphs and adults. SF trials under pilot-scale commercial conditions were also carried out that further supported the efficacy of SF for red-legged ham beetles but not for the ham mite. SF may not be suitable for managing ham mites based on work to date, but future work could investigate longer exposure times at higher temperatures.