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The objective of this study is to investigate the effect of addition of various types of emulsifiers on the morph/ology and thermal and mechanical and properties of organogels. For the preparation of the organogels, γ-oryzanol and β-sitosterol mixed at 60:40 w/w ratio were dissolved in decane containing various types of emulsifiers, including Span 80, PGPR, and lecithin, and co-solvents (butanol and pentanone). The firmness, morphology, and thermal properties of the organogels were studied. SEM micrographs showed branched and twisted strands of the tubular network within the gels prepared in decane. Addition of emulsifiers and co-solvents increased the polarity of the continuous oil phase and noticeably changed the alignment of the tubules. More linear tubular structures that resemble ribbons with elongated tubules were observed. The firmness of the organogels dropped with addition of emulsifiers and co-solvents, except for Span-80, where the firmness is initially increased up to 10% w/w and then decreased. The firmness of the gels prepared with PGPR, lecithin, pentanone, and butanol decreased linearly on increasing the respective emulsifier or co-solvent concentration between 1% and 20% (w/w). The organogels prepared with Span-80 were stronger than those prepared with PGPR and lecithin. Moreover, the gels prepared with pentanone were stronger than those prepared with butanol. In addition, the gel-solution transition temperature of the organogels decreased with increasing emulsifier and co-solvent concentration. The addition of the emulsifiers seems to interfere with the self-assembly of the tubular structure and disturb the organization of the hydrophobic tail of oryzanol-sitosterol in the continuous decane phase. This prevents the formation of a complex branched tubular network resulting in weaker gels.

The effect of the sprouting temperature on wheat sprouting and on the properties of expanded extrudates produced from sprouted wheat flour was studied. Therefore, wheat was sprouted at five different temperatures and subsequently dried, milled, and the resulting flour was used to produce extrudates using a twin‐screw extruder. In order to understand the sprouting temperature effect, the degree of sprouting (DoS) of the differently sprouted samples and characteristic properties of flour and extrudates were studied and compared. During sprouting of wheat with increasing temperature and time an increase of the α‐amylase activity, the vitamin C and reducing sugar content, and a decrease of the peak viscosity was observed. The greatest effect was found at 20°C. Furthermore, the lowering of the viscosity of the flour suspension results in a reduction of the pressure and temperature in the extruder die. The extrudates of sprouted wheat flour were found to be easier to break, had a lower density, an increased longitudinal expansion index, and an improved cold‐water solubility. A good correlation between the DoS and other properties of flour and extrudates was found, indicating a good predictive power and applicability of the DoS concept for wheat samples and their product development and specification.

The present study investigates the use of flour from sprouted wheat for the production of extruded, directly expanded products. Until now, studies on the use of sprouted material in extrusion have not been concerned with differences in the sprouted material. This contribution documents the first attempt to study the effect of the variation of the sprouting process on extrudate properties. Extrudates were produced at standard conditions using material produced by the variation of sprouting times (steeped, 1, 3, 5, 7, and 9 days sprouted). It was found that an increasing duration of the sprouting process also increases the starch degradation and hence sugar generation. During this process, vitamin C levels showed an increase of up to 10‐fold. The accompanying changes in viscosity propagate systematically into different observations. With increased starch degradation back pressures in the extrusion die were reduced, extrudates show less sectional expansion, but densities were decreased because longitudinal expansion was increased significantly. The extrudates made with sprouted material were preferred during sensory assessment. The degree of sprouting, which was defined earlier proved to be a useful property to characterize the progress of the sprouting process and correlated well with changes observed for the sprouted flour and extrudate properties. PRACTICAL APPLICATION: The use of sprouted wheat in the production of direct expanded extrudates is a promising opportunity to change and improve extrudate properties. On the one hand, the nutritional value of the extrudates is improved due to the use of sprouted wheat flour which contains newly synthesized vitamins, more essential amino acids, and a decreased phytic acid content. On the other hand, the texture of the extrudates is improved and less additives are needed in the production. Due to the starch degradation in the sprouting process short‐chain sugars were formed, which naturally increase the sweetness of the extrudates.

The effect of dextran's molecular mass distribution (T40, T500, T2000, and enzymatically decomposed T2000) on the size and shape of calcium carbonate particles precipitated during carbonation, a step in the sugar manufacturing process, was investigated. Image analysis combined with size exclusion chromatography was used to distinguish harmful and harmless dextran sizes aiming at targeted mitigation of dextran‐related effects by dextranase. The data indicate that dextran with molecular masses above 10 kDa promotes agglomeration, indicated by an increase in particle projection area. This effect was especially found for broadly distributed intermediate but rather low molecular mass dextran (10–85 kDa). Based on particle shape data, the agglomeration of calcium carbonate crystals in the absence and in the presence of low molecular mass dextran ( 85 kDa) promotes nonoriented agglomeration and an increase in surface roughness. Once the dextran was significantly decomposed by enzyme action (10 or 50 mg/kg juice) to smaller molecules in the size range below 10 kDa, no dextran‐related effects on particle size and shape were found anymore. PRACTICAL APPLICATIONS: The presence of dextran is known to cause several adverse effects during sugar manufacture. Among them, dextran can affect the size and shape distribution of calcium carbonate particles precipitated during carbonation as a part of the sugar beet raw juice purification. As a result, the purification as well as the filtration process can be affected. These dextran‐related effects are usually mitigated by enzymatic decomposition, a gradual reduction in molecular mass. For a targeted enzyme application, the decomposition products need to be identified and the corresponding effects due to varying molecular mass fractions on the precipitation of calcium carbonate need to be analyzed. Only then, a sufficient decomposition to harmless molecule sizes can be ensured. Thus, the data gathered give a clear guidance for dextranase treatment in sugar manufacture.

The systematic study presented addresses the need to understand the co‐crystallization of beet and cane material better. This is important because of the sugar market liberalization in 2017. Here the effect of crystal growth velocity on final sugar quality is investigated. Comparing three different thermal setups, studying different cane and beet mixtures color inclusion into sucrose crystals was analyzed. Within one thermal setup supersaturation was practically constant. Almost exclusively the time necessary to complete the crystallization at 50% solids level changed. Particle size and distribution remained unchanged. Hence, only the growth velocity varied. Growth rate appears to influence color inclusion less than mixing of beet and cane syrups. In cane syrups the relative color inclusion is the highest and most sensitive to growth velocities. Admixing only 33% of beet syrup, already changes this pattern dramatically and the color transfer factor is more than halved. This effect of beet material is most prominent for the mechanism liquid inclusion but also significant for co‐crystallization of colorants. This observation is possibly due to the different nature of the colorants originating from beet and cane. The findings provide a framework to optimize the space‐time yield under consideration of highest sugar quality to manufacturers. PRACTICAL APPLICATIONS: Co‐production of beet and cane is a promising opportunity to increase competitiveness by increasing utilization of equipment in the seasonal sugar industry. To do so reliably, quality parameters have to be met. The main problem to be solved is the control of white sugar color. Since cane and sugar beet deliver different coloring minor components, their interaction and respective inclusion mechanisms need to be understood. The work presented is part of a comprehensive study to elucidate this area of sugar processing that has not been studied yet. Next to the findings on inclusion characteristic and relative contribution of different mechanisms, the conclusions can directly be transferred into practice. The data gathered give a clear guidance to producers that higher inclusion levels of “colored” material, than current conservative practice dictates, can be tolerated due to the mutual suppression mechanism found.