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Feeding dairy cattle with safe compound feed helps farmers to ensure food safety. However, several ingredients often used in compound feed production can be contaminated with aflatoxin B1 (AFB1), which may result into milk contaminated with aflatoxin M1. Given the number of ingredients and their amounts used in the production of compound feed, it is very costly to check every batch of ingredients for AFB1 contamination. Which is the reason, why a risk-based approach is taken in the latest years. This study aimed to estimate the probability of AFB1 contamination of compound feed for dairy cattle, and to limit this contamination, by optimisation of the compound feed formulation, using a modelling approach. The modelling approach comprised integrating a linear optimisation programming model to a Monte Carlo simulation model. This model was applied to the case of producing compound feed for dairy cattle in the Netherlands, using national monitoring data on AFB1 contamination in feed materials collected in the period 2000-2010. Results from this case study showed the model can be used to produce safe compound feed with the lowest possible probability of AFB1 contamination.

In: World Mycotoxin Journal

To date, several models that predict deoxynivalenol (DON) in wheat at harvest are available. This study aimed to evaluate the performance of two of such models, including a mechanistic model developed in Italy and an empirical model developed in the Netherlands. To this end, field data collected in the periods 2002-2004 and 2009-2011 in Italy, and in the period 2001-2010 in the Netherlands were used. These historical data covered farm observations at 1,306 wheat fields, of which 155 in the Netherlands and 1,151 in Italy. A subset of 10% of the Italian data, derived by random sampling from the total Italian dataset, was used to validate both the Italian and the Dutch model. Additionally, the Italian mechanistic model was validated using the total Dutch dataset. Before validating the Dutch model, it was recalibrated using the remaining 90% of the Italian data. Results showed that predictions of both modelling approaches (mechanistic and empirical) for independent wheat fields were in accordance. Applying a threshold for DON concentration of 1,250 ?g/kg, the mechanistic DON model predicted 90% of the samples correctly. Results for cross-validation of the mechanistic DON model and the recalibrated empirical DON model showed that 93% of the samples were correctly predicted. In general, no more than 6% of underestimates were observed.

In: World Mycotoxin Journal

Projected climate change effects will influence primary agricultural systems and thus food security, directly via impacts on yields, and indirectly via impacts on its safety, with mycotoxins considered as crucial hazards. Mycotoxins are produced by a wide variety of fungal species, each having their own characteristics and requirements. The geographic distribution of toxigenic fungi reflects their ecological needs, with thermophilic fungi prevalent at lower latitudes and psychrophiles at the higher latitudes. A resulting gradient of mycotoxin contamination has been repeatedly stressed. Changes in climatic conditions will lead to shifts in the fungal population and the mycotoxin patterns. In general, climate change is expected to increase mycotoxin contamination of crops, but due to the complexity of mycoflora associated to each crop and its interaction with the environment, it appears rash to draw conclusions without specific studies. Very recently first quantitative estimations of impacts of climate change on mycotoxin occurrence have been made. Two studies each applied models of different disciplines including climate projection, crop phenology and fungal/mycotoxin prediction to cereals cultivated in Europe. They were followed by a case study on climate change effects on Alternaria moulds and their mycotoxins in tomato. Results showed that DON contamination of wheat grown in Europe was, in general, expected to increase. However, variation was large, and in some years and some regions a decrease in DON contamination was expected. Regarding aflatoxin contamination of maize grown in Europe, an increase was estimated, mainly in the +2 °C scenario. Two main research gaps were identified related to the (limited) number of existing quantitative models taking into account climate change and their validation in limited areas. Efforts are therefore mandatory to be prepared for future changes and challenges on model validation and limited mycotoxin-crop combinations.

Open Access
In: World Mycotoxin Journal

Purpose: The research described in this paper is aimed at developing a model for estimation of performance objectives (PO) in the supply chain, based on field data. As a case study, such a model has developed for Salmonella prevalence in the broiler supply chain in the Netherlands.

Methodology/approach: Food safety in the supply chain can be controlled by the application of performance objectives (PO) in the chain. A PO in the final product is pre-set, and translated into PO at previous points of the chain. Applying this concept, an analytical model has been developed for estimation of PO for Salmonella in the broiler supply chain, based on a preset PO in the finished product (end processing). Model development was based on monitoring data on Salmonella prevalence at five sampling points in the chain, covering all slaughterhouses in the Netherlands in the period 2002-2005.

Findings: Reducing the end PO from the reference situation of 2.5% to 1.5% may be practical achievable, but interventions are needed at each stage. An end PO of 0.5% or lower needs substantial effort in all stages, but particularly at the slaughterhouse.

Practical implications: Modeling PO in the supply chain based on monitoring data helps to establish realistic food safety targets and to estimate the effects of potential intervention measures to reduce the end-PO. The developed model is easy to understand by policy makers, and helps to focus on those points in the supply chain that need further attention.

In: Towards effective food chains

Barley is a small-grain cereal that can be infected by Fusarium spp. resulting in reduced quality and safety of harvested barley (products). Barley and other small-grain cereals are commonly studied together for Fusarium infection and related mycotoxin contamination, since the infection and its influencing factors are assumed to be the same for all small-grain cereals. Using relevant literature, this study reviewed Fusarium spp. infection and mycotoxin contamination, mainly T-2/HT-2 toxin and deoxynivalenol (DON), in barley specifically. For the first time, review results provide an extensive overview of the influencing factors for Fusarium infection and mycotoxin production in barley, such as weather, agricultural management and processing factors, and includes the comparison of these mechanisms in wheat. Results showed that Fusarium infection in barley is difficult to recognise in the field and mycotoxin levels cannot be estimated based on the symptoms. These factors make it difficult to establish the real severity of Fusarium infection in barley. In addition, most pre-harvest measures to mitigate initial Fusarium infection, such as cultivar use and soil cultivation, are the same for barley and wheat, but due to anatomical differences, some pre-harvest measures have a different effect on Fusarium infection in barley. For example, the effective moment (days after anthesis) of fungicide application in barley and wheat is different. Also, in wheat, there is an additional effect of multiple fungicide applications in reducing Fusarium Head Blight and DON concentrations, whereas in barley, no additional effect of multiple application is seen. Hence, care should be taken to use data from one small-grain cereal to draw conclusions on other small-grain cereals.

Open Access
In: World Mycotoxin Journal

Abstract

Insects are receiving increasing attention as a possible ingredient for feed and/or food production. When used efficiently, insects can provide a sustainable and economically favourable contribution to global food security. Housefly larvae (HFL) can grow on a variety of organic side streams and upgrade them by partial conversion into high-quality protein. Organic side streams may be chemically contaminated by naturally occurring toxins, e.g. mycotoxins, therefore, effects on insect survival and biomass as well as other feed and/or food safety issues should be investigated. In this study, the HFL were exposed to a feed substrate spiked with aflatoxin B1 (AFB1), deoxynivalenol (DON) or zearalenone (ZEN) at concentrations of either 1 or 10 times the maximum levels or guidance values set for feed materials by the European Commission. Mortality and biomass of HFL were recorded over five days of exposure. LC-MS/MS analysis was used to determine the concentration of the mycotoxins in the substrate offered, the larvae and the residual feed material. A molar mass balance was calculated to estimate how much of the spiked mycotoxins (and several metabolites), was recovered in the larval body and the residual material. Exposure to either of the three mycotoxins did not affect larval mortality and biomass, and accumulation in the larval body did not take place. Metabolism does seem to occur for AFB1 and ZEN as the molar mass balance revealed an unrecovered fraction of ca. 40-50%. Little DON metabolism occurred as most of the initially present DON was found back unchanged. The results of this study support the potential for safe use of HFL as food- and/or feed when reared on mycotoxin contaminated side-streams, as accumulation of the tested mycotoxins did not take place in HFL. Further research is needed to identify the fate of the unrecovered fractions of AFB1 and ZEN.

Open Access
In: World Mycotoxin Journal

Despite growing interest from entrepreneurs, knowledge on the profitability of commercial-scale insect production is scarce. Insight into the economic figures of insect production is needed by farmers aiming to start insect farms, by banks seeking to provide financing, and by governments planning policy interventions. This review provides an overview of the profitability and underlying economic figures relating to the production of Hermetia illucens, Alphitobius diaperinus, Tenebrio molitor and Acheta domesticus. To enhance data interpretation, we also provide a brief overview of the global insect sector, with specific attention to farm-level operational practices. Sales prices refer to fresh larvae, dried larvae or larvae meal, whereas operational costs include costs for feed, labour, electricity, water and gas. Operational cost components differ per insect species, and therefore the relevant margins are specified for three insect species. The energy, feed, and labour margin for production of H. illucens ranges from € -798 to 15,576 per tonne of dried larvae. The feed and labour margin for production of T. molitor ranges from € 7,620 to 13,770 per tonne of fresh larvae. For production of A. domesticus the feed margin ranges from € 12,268 to 78,676 per tonne of larvae meal. The margin range for A. diaperinus cannot be estimated, due to a lack of data in the literature. The ranges mainly reflect the differences in sales prices, which are found to heavily depend on the geographical market location, type of market (feed or food) and quantity sold. Major operational costs include feed and labour, with feed costs varying substantially within and between insect species. The economic figures and margins presented in this article provide a foundation for the further development of the insect production sector.

Open Access
In: Journal of Insects as Food and Feed

Abstract

Insects are increasingly considered as a relevant alternative protein source in the transition to a more circular economy and more sustainable food production. Understanding the profitability of insect farms is crucial for starting entrepreneurs, established rearers, and third parties. In this study we analysed the revenues and expenses of seven T. molitor farms in the Netherlands, representing approximately a quarter of the total sector. We calculated their gross margin and net present value. Revenues came from the sales of fresh larvae and insect frass, and from extension services. Expenses included investments, and non-allocated and variable expenses. Results cover technical and economic results, and a qualitative description of farm operations. The gross margins and net present values ranged from −180 to 2,030 and from −12,359 to 15,535 EUR/tonne fresh larvae production, respectively. The main determinants of T. molitor farms’ profitability included the sales price of larvae, and its labour and substrate expenses. Our estimates can be used by decision making of farmers, credit providers, and policy makers to support the growth of this still very small, but emerging sector.

Open Access
In: Journal of Insects as Food and Feed

Abstract

Edible insects such as lesser mealworm (Alphitobius diaperinus) are a promising new protein source for food and feed. The feed substrate on which these insects are reared may be contaminated with residues of insecticides originating from agricultural products that may impact insect performance. In this study, two generations of A. diaperinus were chronically exposed to spinosad (2.0 and 0.2 mg/kg) and imidacloprid (0.1 and 0.01 mg/kg) in the substrate. The aim was to determine sublethal effects on performance measures (total biomass (yield), mean individual weight, number of alive individuals) of larvae, pupae, and adult beetles, as well as pupation and eclosion. Exposure to spinosad at 2.0 mg/kg resulted in significant adverse effects on most performance measures of larvae, of both generations. Imidacloprid caused a reduction in yield and mean individual weight of the larvae as compared to the control at 0.1 mg/kg, while an increase in those measures was observed at 0.01 mg/kg. Significant adverse effects on adult beetles were only observed for imidacloprid at 0.1 mg/kg, and no significant effects of this insecticide on pupation and eclosion were observed. The concentrations of tested substances in larval samples were negligible for both generations, however, transfer from substrate to larval biomass was higher in the offspring generation relative to the parent generation. More research is needed to fully assess the hazard of insecticide residues to cause sublethal effects on A. diaperinus, for which method development for more cost-efficient designs is required.

Open Access
In: Journal of Insects as Food and Feed

Black soldier fly (BSF, Hermetia illucens) larvae is considered one of the insect species with great potential for large-scale production as feed and food. For this to become economically feasible and to contribute to a circular economy, BSF larvae should be reared on substrates with little or no alternative use for feed and food production. One such class of alternative substrate sources consists of former food products. However, BSF larvae may accumulate chemical contaminants from the substrate, which may originate from the foodstuff and/or the packaging materials. This study aimed to investigate the possible presence of chemical contaminants in BSF larvae being reared on former foodstuff substrates at both laboratory and industrial scale. Four experimental treatments were set up: with meat or vegetarian, and containing between 3-6% of either plastic or paperboard carton packaging material. Four-day old BSF larvae were reared for seven days on these substrates. Concentrations of heavy metals, mineral oil hydrocarbons, dioxins and PCBs, and polycyclic aromatic hydrocarbons were determined in the substrate, residual material, and the larvae. Results suggest that BSF larvae can be reared on former food products containing traces of packaging materials, without negative effects on their growth or survival. Bio-accumulation was observed for most of the tested contaminants, in particular for mineral oils and cadmium, which had a bio-accumulation rate of, respectively, about five and 20. However, none of the concentrations of the analysed contaminants in the substrate and the larvae exceeded the respective legal limits in the EU. Results of this pilot study were promising. As a next step, more different former food products should be investigated in future research.

Open Access
In: Journal of Insects as Food and Feed