Kakaopulpe : Rohmaterial mit Potential

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Single bubble deformation and breakup in simple shear flow

Experiments in a parallel band apparatus and a transparent concentric cylinder device allow the observation of bubble deformation (shape and orientation) and breakup as a function of the viscosity ratio λ and the Capillary number Ca. For viscosity ratios between 3.1×10−7 and 6.7×10−8, critical Capillary numbers Ca c for bubble breakup between 29 and 45 are found. It is furthermore shown that in the given parameter space no clear distinction between tip breakup and fracture can be made for bubble

Occurrence of zearalenone and enniatin B in Swiss wheat grains and wheat flours

Wheat is one of the world’s key staple foods, but it is often contaminated with mycotoxin-producing microorganisms, resulting in a large amount of food waste every year. The contamination of wheat grains harvested in 2020 and 2021 in Switzerland, as well as of wheat flours bought in local stores with the two mycotoxins zearalenone (ZEA) and enniatin B (ENB) was investigated. The quantification was performed using LC–MS/MS. ZEA, the level in different cereals and food products of which is regulated by law, was detected in half of the grain samples at levels below 100 µg/kg, except for one sample contaminated with 147 µg/kg. No ZEA was detected in the commercial wheat flours. The emerging mycotoxin ENB was detected in all samples of wheat grains and flours, at levels between 3 and 938 µg/kg. The harvest year was shown to affect the ENB content (p value < 0.01), and in particular the humid weather conditions encountered in 2021 during the month of harvest. The refining grade of the flours showed no influence on the contamination by ENB, indicating that the contamination with ENB can occur not only on the surface layers but also on the inner layers on the wheat grain. As chronic exposure to ENB can therefore not be excluded, decontamination solutions are needed to prevent food waste and further improve the food safety of wheat-based products

Heat and shear stability of particle stabilised foams for application in gluten‑free bread

Erworben im Rahmen der Schweizer Nationallizenzen (http://www.nationallizenzen.ch) ​Bread forms an integral part of the daily diet in many cultures worldwide. At the same time, a signifcant number of people try to avoid wheat-based products for either health reasons or due to personal preferences. The absence of a protein network in gluten free bread afects its structure, taste, texture and shelf-life. This paper suggests a technological solution to this issue that uses a pre-foamed mass of gluten free raw materials which is mixed with the bread’s ingredients, then kneaded and baked to form a high quality gluten free bread. To survive the high shear stresses during kneading and temperature increase during baking, the foam requires exceptional stability. This stability was achieved through particle stabilisation of the bubble inter faces. Both of the tested foams (with and without particles) exhibited thermal stability up to 80 °C. However, resistance to shear stresses was higher in the particle stabilised foams. Of all the tested particles, linseed press cake and banana powder led to the best results. In conclusion, particle stabilised foams seem very well suited to applications in gluten free baked goods. Further application potential is seen for vegan foamed desserts

Assessment of the suitability of millet for the production of pasta

In temperate climate zones such as Switzerland, wheat is exposed to increasing heat and water stress due to climate change. Millet is a promising alternative crop with a high heat resistance and the additional benefit of being gluten-free. However, the market for organic Swiss millet within Switzerland is saturated with the current product portfolio of flakes or dehulled millet. Therefore, novel end products with a high millet content, such as pasta, could play a key role in increasing consumer demand. Against this background, the suitability of the millet (Panicum miliaceum L.) variety Alba for producing spaghetti was investigated. To optimize the quality of the millet spaghetti, different pre-treatments and recipes were tested, i.e., hull particles were sieved out of the flours and blends with other gluten-free and gluten-containing flours were tested. Finally, the best types of spaghetti were subject to sensory testing, and the color and texture were both quantified. In addition, nutritional quality was assessed. The analytical results showed that a firmness comparable to durum spaghetti was reached for pure millet, 50% millet mixed with 50% corn and rice flour (95:5), and 15% millet mixed with 85% durum wheat. The brownish appearance, slightly rough surface, and nutty flavor of the spaghetti made from millet was especially popular among consumers with a diet-conscious lifestyle. The millet pasta had a high content of iron, zinc and dietary fiber. Since the production processes were able to be implemented in industry without major additional costs, implementation in the market seems feasible

Evaluation of the effect of a novel membrane filtration system on the life span of frying oil

Frying oil has a limited lifetime which results in the disposal of approximately 67% of all used oil. The aim of this study is to determine the suitability of different membranes for purifying frying oil and investigate the application of continuous membrane filtration in a commercial deep fryer. Eleven different membranes were tested to assess their suitability for filtrating frying oil. A prototype continuous filtration system with an integrated membrane filter was developed for a deep fryer to assess the effect of continuous membrane filtration on oil degradation. The prototype was subjected to a frying test over 13 days and the results compared to those from a standard deep fryer. The prototype maintained total polar compounds (TPC) at an acceptable level of 27%

Effect of particle characteristics and foaming parameters on resulting foam quality and stability

Highlights: • Use of particles without emulsifier reduced median bubble size and improved foam stability. • Combining PGE emulsifier and particles resulted in higher foam stability. • Particularly low drainage was observed in particle stabilized foams using banana powder. • Increases in particle size and wetting angle correlated with reduced drainage. • High shear rates were strongly associated with narrower bubble size distributions.In this study, the effects of ten different food-grade particles on bubble quality and stabilization of particle-stabilized food foams in batch and continuous foaming with and without polyglycerol ester (PGE) as an emulsifier were investigated. Particle properties, such as contact angle and porosity, and varying process parameters, such as shear rate and gas fraction, were assessed with respect to their impact on bubble size x50,0, bubble size distribution width and drainage. The smallest bubble size x50,0 in foams without PGE could be achieved with banana powder (88 μm), calcium carbonate (89 μm) and microcrystalline cellulose (79 μm) particles. In comparison, the smallest size in the reference without particles were 105 μm. Combining the use of particles with PGE further reduced bubble size by up to 57% and drainage by up to 100%. Increasing the shear rate from 4922 s−1 (35 μm) to 9844 s−1 (14 μm) resulted in smaller mean bubble sizes and significantly narrower bubble size distributions whereas no distinct correlation between gas fraction and resulting bubble size was found. This study shows that using suitable particles in combination with an optimized foaming process promotes both bubble quality and the stability of foams

Design and functionality of a prototype for cold needle perforation of wheat

Wheat is a vital crop in global food security, but up to 25% of the wheat harvested is contaminated with mycotoxins that have detrimental effects on human health. To address this issue, biological detoxification strategies have been developed using microorganisms and enzymes. Perforating the whole wheat kernel using cold needle perforation (CNP) followed by a detoxification step could be a promising approach to reduce cross-contamination during the milling of mycotoxin-containing wheat. In this study, a pilot-scale CNP prototype was developed to perforate wheat kernels, and its effectiveness was evaluated. The height-adjustable perforation unit consists of 3120 needles. The throughput of the CNP prototype was adjusted to 6 kg/h, and the kernels were perforated for 1, 5, or 10 cycles. The results show that the CNP prototype effectively perforates wheat kernels, as evidenced by the significant increase in pore count. Fluorescence microscopy confirmed the penetration of particles in the size range of enzymes and microorganisms into the kernel. This study demonstrates the successful scale-up of CNP for wheat kernel perforation and highlights the potential of CNP as a cost-effective and efficient method for the biological detoxification of mycotoxin-contaminated wheat

Portafolio evaluativo: una herramienta para la autonomía

Ningun

Evaluation of innovative technological approaches to replace palmoil with physically modified Swiss rapeseed oil in bakery products

Palm fat is often used in baked goods because of its relatively low cost, and its positive impact on texture and shelf life. Demand for alternatives has risen in recent years due to concerns about the ecological and social sustainability. This is a challenge for the bakery industry since palm oil possesses unique properties. In this study, unhydrogenated rapeseed oil was processed using novel physical technologies, such as wax crystallisation, stabilized foaming and Pickering emulsions, in order to simulate palm oil properties. Analysis showed that while the initial viscosity of the fat substitute products was low compared to palm fat, the fat replacement products behaved very similarly to palm fat in the baking experiments. The resulting biscuits baked with emulsified rapeseed oil and rapeseed oil complemented with wax crystals were judged to be suitable replacements for palm fat in terms of processability, as well as analytical and sensory assessment