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The number of people buying gluten-free breads and baked goods is increasing. To optimise the quality of gluten-free breads, fat and additives are still often used. This project investigated whether the use of particle-stabilised foams could eliminate or at least reduce the need for large amounts of fat and additives in gluten-free toast bread. Hence, particle-stabilised foams were added to bread doughs, kneaded in, baked and then analysed. The breads containing particle-stabilised foams had no significant difference in firmness nor in adhesiveness compared to gluten-free toast bread with additives or to the gluten-containing bread. While the volume of the toast bread containing foam was lower than for the gluten containing reference toast bread, it had up to 2.0–2.5 times the volume than the gluten-free bread reference without additives. These results showed a positive influence of the use of particle-stabilised foams in gluten-free bread without addition of additives.

The roller milling of sorghum and quinoa seeds into flour fractions (coarse, middle, and fine) was investigated, chemically analysed, and applied in the baking of gluten-free sourdough bread. The gap settings were adjusted to 0, 5, 8, and 10 for quinoa, and 3, 5, and 7 for sorghum. The fine fractions reached values of up to about 41% (gap 8) for quinoa and around 20% for sorghum (gap 5). SEM pictographs illustrated the clear separation of each fraction with the chemical analysis showing high contents of protein, TDF (total dietary fibre), and IDF (insoluble dietary fibre) in the coarse fraction. Up to 77% starch content was obtained in the fine fraction with significant amounts of SDF (soluble dietary fibre), which has good health benefits. Increasing the dough moisture up to 90% helped in decreasing the bread crumb firmness, while low Avrami parameters and RVA pasting behaviour indicated a slow bread-staling rate for both sourdough breads.

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.

Erworben im Rahmen der Schweizer Nationallizenzen (http://www.nationallizenzen.ch)​, Vacuum cooling of baked goods can deliver many advantages in terms of product quality and productivity, such as higher volumes and shorter cooling times. However, the associated high costs and the need to adjust baking protocols are of relevance and more information is needed. This paper examines the influence of two main baking protocol parameters on the quality of toast bread, i.e. oven temperature and baking time reduction. Resulting toast bread characteristics including specific bread volume, concavity, browning index, crust and crumb hardness and aw-value were analysed as well as process-dependent core temperature and water loss. In order to compensate for water loss during vacuum cooling and still achieve optimal toast bread quality, a final bread core temperature of 98 °C at the end of baking gave best results, regardless of oven temperature. It was further shown that cooling time can be reduced by a factor of 10 if the baking protocol is optimally adjusted, hinting at a huge potential to increase productivity for industrial applications. In summary, it can be stated that vacuum cooling requires a tailored reduction in baking time in order to compensate for water loss from vacuum cooling while retaining sufficient structural cohesion to resist deformation of the bread.

Functional lactic acid bacteria (LAB) as starter cultures used in sourdough fermentation have been researched for years. This study evaluated the LAB strains Leuconostoc citreum DCM65 (mannitol, exopolysaccharide producing, antifungal activity) and Lactiplantibacillus plantarum subsp. plantarum MA418 (amylolytic activity) and their potential as single or co-culture starters in sourdough fermented buns containing different levels of sugar (control 9% and reduced 0, 3, 6%). Cell counts, pH development, and organic acids were determined before and after sourdough fermentation (30 °C, 24 h) and physical properties (color, volume, pore structure, and texture) of buns produced thereof were determined after baking. Sourdoughs started with DCM65 and/or MA418 developed up to log 9.2 CFU/g presumptive LAB after 24 h, assertiveness of the added starter cultures species was confirmed by MALDI-TOF MS. Acetic acid and mannitol were only detected in sourdough fermented with DCM65 (single or co-culture) up to 2.5 mg/g and 9.8 mg/g, respectively. The starter cultures applied influenced physical properties of buns. Sourdough buns started with MA418 had higher volume and slice area, and softer crumb; in contrast, buns fermented with DCM65 had a finer pore structure. In summary, both starter cultures showed high potential in sourdough buns with reduced sugar content.