Food contact materials (FCMs) i.e. materials that food is packaged or handled in, must be safe for their intended use. European FCM legislation uses a risk-based approach, with a cornerstone of FCM’s safety evaluation being measurement of migration of substances from FCMs to food simulants. The standard methods mainly developed for plastic FCMs are not always suitable for less inert and moisture sensitive materials such as paper and board. However, these are becoming increasingly common as FCMs e.g. to replace single-use plastics. In addition, there is a drive to further use recycled materials. To support this development, new methods for assessing the safety of these materials are needed. In the present feasibility study, a hydrogel crosslinked through freeze-thawing of poly(vinyl alcohol) was evaluated as a food simulant for moist foods. The migration of surrogate compounds from a spiked paperboard to the hydrogel was determined and compared to the migration to a real moist food (a slice of apple), the commonly used modified polyphenylene oxide (MPPO) and a water extract. Migration of polar surrogates to the hydrogel correlated well with the migration to the apple slice. However, our results indicate that the hydrogel is less suitable as simulant for non-polar surrogates. Overall, the study demonstrates the potential of this hydrogel-based simulant for improving risk assessment of less inert FCMs. 

The current global sodium consumption exceeds recommended daily intakes and there is a great need to reduce the sodium content in foods for a healthier society. The current study investigated the effect of combining sensory interaction principles and heterogeneous distribution of NaCl in bread on sensory properties, structure, and NaCl distribution. Breads were prepared in three different arrangements of NaCl distribution: homogenous, layered, and layered with lactic acid. Within each arrangement, four NaCl levels were tested. The breads were evaluated by a sensory panel for perceived saltiness, sourness, and qualitative texture, measured for stiffness, and the NaCl distribution was determined by X-ray fluorescence microscopy (XFM). Perceived saltiness was significantly enhanced in breads beyond heterogeneous NaCl distribution when lactic acid was added. Stiffness measurements were affected by layering of bread, the layers without NaCl were stiffer with an increase in overall salt concentration. The heterogeneous distribution of NaCl in layered breads could be visualised by XFM and textural consequences of layering bread are discussed. The current study demonstrates the potential of combining principles of pulsation of taste and sensory interactions together to enhance salt perception, and hence suggesting the approach as a possible further strategy for NaCl reduction in bread.

A new concept has been developed for characterizing the real-time evolution of the three-dimensional pore and lamella microstructure of bread during baking using synchrotron X-ray microtomography (SRµCT). A commercial, combined microwave-convective oven was modified and installed at the TOMCAT synchrotron tomography beamline at the Swiss Light Source (SLS), to capture the 3D dough-to-bread structural development in-situ at the micrometer scale with an acquisition time of 400 ms. This allowed characterization and quantitative comparison of three baking technologies: (1) convective heating, (2) microwave heating, and (3) a combination of convective and microwave heating. A workflow for automatic batchwise image processing and analysis of 3D bread structures (1530 analyzed volumes in total) was established for porosity, individual pore volume, elongation, coordination number and local wall thickness, which allowed for evaluation of the impact of baking technology on the bread structure evolution. The results showed that the porosity, mean pore volume and mean coordination number increase with time and that the mean local cell wall thickness decreases with time. Small and more isolated pores are connecting with larger and already more connected pores as function of time. Clear dependencies are established during the whole baking process between the mean pore volume and porosity, and between the mean local wall thickness and the mean coordination number. This technique opens new opportunities for understanding the mechanisms governing the structural changes during baking and discern the parameters controlling the final bread quality. © 2023 The Author(s)

As life expectancy increases so do age related problems such as swallowing disorders, dysphagia, which affects 10%–30% of people over 65 years old. For dysphagia patients the texture and rheological properties of the food, and the bolus, is critical to avoid choking and pneumonia. Texture modified foods, timbals, are often served to these patients due to their ease of swallowing. The main concern with these foods is that they do not look visually alike the food they replace, which can decrease the patient’s appetite and lead to reduced food intake and frailty. This study aims to improve both the visual appearance of texturized food as well as the energy density and fiber content of the timbal formulation. 3D scanning and additive manufacturing (3D Printing) were used to produce meals more reminiscent of original food items, increasing their visual appeal. Rheology was used to ensure the original flow profile was maintained as the timbal was reformulated by reducing starch contents and partially replacing with dietary fibers. The amount of starch was reduced from 8.7 wt% in the original formulation to 3.5 wt% and partially replaced with 3 wt% citrus fiber, while maintaining properties suitable for both swallowing and 3D printing. The resulting formulation has improved nutritional properties, while remaining suitable for constructing visually appealing meals, as demonstrated by 3Dprinting a chicken drumstick from a model generated with 3D scanning.

Preslaughter handling inevitably exposes cattle to stress, which affects beef quality and yields. Short transports to the slaughterhouse or a short walk across the yard to a mobile abattoir parked on the farm may reduce stress, with potential beneficial effects on meat quality. To compare different road transport distances to a stationary (fixed) slaughterhouse, and the stationary plant with a mobile abattoir, we studied commercial slaughter of 298 cattle in each facility over a period of 13 months. For the stationary slaughterhouse, the estimated transport distance from farm to plant was 7–250 km (mean 99 km) and 96 animals spent one night in lairage there. All animals at both slaughterhouses were stunned with a captive bolt gun. Blood levels of cortisol, glucose and lactate at exsanguination and meat quality indicators were recorded. According to two-sample t-tests, thawing loss was 1 percent unit lower (p<0.0001), Warner-Bratzler shear force was 6.9 N lower (p<0.0001) and compressive load was 3.9 MPa lower (p<0.0001), but mean lactate level was 1.02 mmol/l higher (p<0.0001) and ultimate pH was 0.05 units higher (p=0.0001) in the mobile facility compared with the stationary. Effects of slaughter facility and estimated road transport distance to the stationary plant on blood lactate, ultimate meat pH, shear force and compressive load were analysed by generalized linear mixed models, with delivering farm as random effect. According to the models, predicted shear force was 23% higher at the 95th percentile of the transport distance compared with the 5th percentile (p=0.012), and there was some evidence of a similar difference in compressive load for heifers, albeit only marginally significant (39% higher at the 95th percentile; p=0.056). Predicted blood lactate was 19% higher in the mobile abattoir than the stationary slaughterhouse (p=0.046). Ultimate meat pH was higher in the mobile unit for cows and steers (p≤0.0020), and for carcasses weighing 311–380 kg (p≤0.0020). Compressive load was 27% lower in the mobile abattoir, compared to the stationary (p<0.0001), but shear force did not differ significantly between the two facilities. This study shows a negative effect of long transport distances on beef tenderness. It also provides evidence of differences in beef quality between a mobile abattoir and a stationary slaughterhouse, although these differences may be attributable to specific routines for carcass handling and ageing at the studied facilities, and not the transport and slaughter strategy itself. 

This study evaluated the effects of different lamb production systems on live weight gain (LWG), carcass quality and meat quality. Four production systems for weaned intact male lambs were examined: Indoor feeding with grass silage and concentrate (group 1), grazing on cultivated pasture with (group 2) or without (group 3) concentrate, and grazing on semi-natural pasture (group 4). Live weight, carcass weight, dressing percentage, carcass conformation, fatness and pH decline were recorded at slaughter, and M. longissimus thoracis et lumborum was analysed for colour, thawing and cooking loss, pH after 24 hours and 6 days, and Warner-Bratzler shear force. LWG was strongly affected by production system, being highest for group 1 and lowest for group 4 (p<0.001). Group 4 had the lowest conformation (p=0.002) and fat scores (p<0.001). Hence, production system affected age at slaughter, live weight gain, weight at slaughter, carcass conformation and fatness scores, but caused no differences in meat quality attributes in intact male lambs.

Microstructure codes for the properties of food. Processing enables the microstructure. Food microstructures are in most cases hierarchical, heterogeneous, multiphase, and complex. A full understanding of the food microstructure requires the characterization at many different length scales. Light microscopy and confocal laser scanning microscopy are powerful tools to image food microstructures at the micrometer level. In this chapter, the principles and use of these microscopy techniques are described. Examples of the use of light microscopy and confocal laser scanning microscopy to characterize and understand the microstructures in bread and dough, fibrous vegetable protein structures, plant cell walls, fat-rich food, and mayonnaise are discussed. In the end, an outlook on the use of light microscopy and confocal laser scanning microscopy in foods is given..

Encapsulation of polar and non-polar bioactive compounds from bilberries was achieved by designing microcapsules with bilberry seed oil (BSO) distributed in an aqueous phase of anthocyanins (AC) stabilized by whey protein isolate (WPI). Non-thermal emulsification method (o/w/o) was developed and the effect of pH (3 or 4.5), concentration of WPI (8.4–10.8% w/w), addition of AC (72–216 ppm) and emulsifier on the structure-forming kinetics, resulting microstructure during storage and after centrifugation and washing was investigated. Agglomeration of BSO was observed in all microcapsules at pH 4.5 due to slow gelling process and in samples at pH 3 at low concentrations of WPI (≤8.4%). Capsules with pH 3 (9.6–10.8% WPI) had weak structures but as the gelling process was faster, it generated an even distribution of BSO droplets. All samples at pH 4.5 and samples with WPI concentration ≥10.8% at pH 3 exhibited intact structures after centrifugation and washing.

The objective of this work was to explore the storage properties of a structured oil-in-water emulsion containing both water- and fat-soluble bioactive compounds from bilberries (Vaccinium myrtillus L.). Bilberry seed oil (BSO) was dispersed in a continuous aqueous phase of anthocyanins (AC) and whey protein isolate. The microstructure was evaluated using light microscopy and the effect of anthocyanins on lipid oxidation and microbial growth was investigated. The results showed that it was possible to generate a stable emulsion structure that resisted phase separation during 25 weeks of storage. Gas chromatography–mass spectrometry measurements of the fatty acids in the BSO during storage showed that AC had a protective effect against lipid oxidation. The AC did not have an antimicrobial effect against the investigated strains Zygosaccharomyces bailii (ATCC 42476) and Aspergillus niger (ATCC 6275 (M68)).