Functional properties of acid‐thinned potato starch: impact of modification, molecular starch characteristics, and solution preparation

A matrix of 27 acid‐thinned (AT) potato starch (PS) samples is prepared in a laboratory scale in slurry by gradation of the process parameters temperature (30, 40, and 50 °C), acid concentration (0.3, 0.6, and 0.9 m HCl) and time (4, 10, and 20 h), and is investigated in terms of functional properties (range of molar mass [Mw] between 17.7 × 106 and 1.95 × 104 g mol−1). The solubility (S) increased basically with a higher degree of molecular degradation and disintegration temperature, and the viscosity decreased systematically with decreasing Mw and increasing disintegration temperature. The existence of a specific Mw range of the starch to achieve highest gel strength is proved. However, an impact of the molecular properties on the light transmittance (Tgel) can be excluded, since all starch gels are opaque. A correlation between the strength and the specific non‐freezable bound water content (wnf) of the gels is found. High gel strength is accompanied by comparatively low wnf. In particular, the viscosity (processing) and the gel strength (final product characteristic), which are important technofunctional properties for the industrial application of AT starches, are found to be directly correlated to the Mw of the starch product. Moreover, the latter is controllable by the hydrolysis process parameters.TU Berlin, Open-Access-Mittel - 201

Sprouting of oats: a new approach to quantify compositional changes

Background and objectives: The aim of this research was to gain a deeper insight into the effect caused by the addition of sprouted oat to food products. The effect of temperature and duration of the sprouting process was systematically studied by sprouting oat grains between 10 and 30°C for up to 3 days. Findings: Overall, it was found that temperatures between 20 and 25°C yield the most dramatic changes in the properties of sprouted oats. Based on the data, a simple system to characterize the sprouting progress by a visual inspection of the lengths of the coleoptile and radicles was developed. This degree of sprouting (DoS) was correlated with further grain properties. Conclusions: It was found that an exponential relationship between the DoS and grain properties existed. Furthermore, the observed increase in the reducing sugar content (up to 14.6 g/100 g) with increasing DoS was closely related to the increase in α‐amylase activity (up to 25 U/g). Significance and novelty: The good predictive power found indicates that the application of the concept degree of sprouting could develop into a reliable characterization method for sprouted grains usable for product development and specification.TU Berlin, Open-Access-Mittel - 201

On the Relation of Entropy and Enthalpy of Fusion in Triglycerides

This contribution presents an extensive literature survey of the calorimetric properties, namely enthalpy and entropy of fusion, of alkyl‐based molecules. Building on the well‐known linear correlation of the named properties to the carbon number in n‐alkanes, saturated fatty acids (FA), and saturated monoacid triglycerides (TAGs), the calorimetric properties of TAGs are reviewed. No straightforward correlation using a single ordering parameter, i.e., carbon number, can be derived for TAGs. This is not surprising due to the complexity of this particular class of molecules differing in alkyl‐chain distribution over the glycerol backbone and chain saturation. A linear correlation of enthalpy and entropy of fusion is evident for molecule classes for which both properties correlate linearly with the carbon number, e.g., n‐alkanes. Despite the complexity of TAGs, it is possible to establish a linear correlation between enthalpy and entropy of fusion even though no underlying single ordering parameter can be identified. A linear fit reveals discrepancies between saturated and unsaturated molecules but independence of polymorphic forms and chain length differences in mixed‐acid TAGs. Moreover, the slopes of the linear fits for data on n‐alkanes, saturated FA, and saturated mono‐acid TAGs are found to be in the vicinity of the melting temperature of polyethylene

Modification of Starches with Different Amylose/Amylopectin‐Ratios Using the Dual Approach with Hydroxypropylation and Subsequent Acid‐Thinning—Impacts on Morphological and Molecular Characteristics

Commercial starches with different amylose (AM)/amylopectin (AP)‐ratios (waxy potato: WxPS, regular potato: PS, high AM corn: HACS) are hydroxypropylated (HP, pilot plant scale, two levels) and subsequently acid‐thinned (AT, laboratory scale) to produce dual‐modified samples. The gradation of the molar substitution (MS) obtained is significant for each starch basis. Investigation by means of scanning electron microscopy reveals a basically intact granular structure with surface defects. The molecular properties are comprehensively characterized using size exclusion chromatography‐multi angle laser light scattering‐differential refractive index detection (SEC‐MALS‐DRI) and corresponding conventional calibration (SEC‐cal‐DRI). The evaluation of the molecular data (MS and weight average molar mass, Mw) by means of statistical analysis (ANOVA) identifies statistically significant impacts with respect to the starch type, the substitution level, and the AT treatment.TU Berlin, Open-Access-Mittel – 202

A Configurational Approach to Model Triglyceride Pure Component Properties

In this contribution, a new model to predict the thermodynamic properties, namely enthalpy of fusion (ΔHf) and melting temperature (Tm), of pure triglycerides (TAGs) is presented. Different contributions to these properties could be expressed by means of repetitive structural attributes deduced from molecular structures. Carefully formulated configurational and geometrical simplifications enabled to attribute physical meaning to most of the parameters. Overall, the number of adjustable parameters is successfully minimized to less than half compared to the well‐known model proposed by Wesdorp in “Liquid‐multiple solid phase equilibria in fats: theory and experiments” (1990). Comparing both models revealed that the new model surpasses the reference model considering desirable prediction quality, thermodynamical consistency, and the number of adjustable parameters. Practical application: The successful description of the phase behavior of TAG mixtures is crucial to understand complex phenomena in fat‐based products. This objective is based on reliable predictions of pure component properties and non‐ideal mixing in liquid‐ and solid‐phases. The newly formulated model gives reliable descriptions of experimental data and predictions of unknown data of TAGs — both thermodynamically consistent. Those are of benefit as prerequisite for any meaningful effort to predict the solid‐liquid phase behavior of TAG mixtures as well as crystallization kinetics

Oleogelation: From Scientific Feasibility to Applicability in Food Products

Oleogels offer the possibility to replace conventional saturated fatty acid (SAFA)‐based lipids with a healthier alternative by immobilizing liquid edible oils in a 3D‐network which is provided by an oleogelator. Numerous molecules which can structure oils rich in (poly)unsaturated fatty acids have been identified. These differ greatly in their chemical composition, network formation, and interactions and thus macroscopic properties of the respective oleogels. Oleogels have been a focal point of food research for over 20 years, yet product applications are lacking. Hence, the question arises whether the application of oleogels is unfeasible or if science lost sight of its objective. This review aims to assess different structuring systems concerning their availability, their potential for the utilization in food products and, if possible, their prices. Moreover, recent studies comprising the application of oleogels in food products are reviewed with special emphasis on the state and the function of the lipid phase during processing and in the final product. Therefore, the physical properties and preparation methods of different oleogels need to be considered in connection with the respective food application. Finally, it is discussed whether the application of oleogels is justified in these products and advantageous in comparison to liquid oil. Practical Applications: A diet rich in mono‐and polyunsaturated fatty acids which make up the majority of liquid edible oils lowers the risk to suffer from cardiovascular diseases. Unfortunately, these oils cannot provide texture to food products in their native state. Oleogelation has the potential to deliver the solid structure necessary for numerous food products by transferring an oil rich in essential fatty acids into a solid‐like structure. Besides, the nutritional value of these oils remains practically unchanged. Although oleogelation has been the objective of various research groups for more than 20 years, product applications are scarce. This review aims to stimulate the mindfulness of research concerning the successful application of oleogels in food products. This hopefully enables a better connection between science and industry.TU Berlin, Open-Access-Mittel – 202

Improving the nutritional profile of culinary products: oleogel-based bouillon cubes

Structured fat phases are the basis of many consumer relevant properties of fat-containing foods. To realise a nutritional improvement – less saturated, more unsaturated fatty acids – edible oleogels could be remedy. The feasibility of traditional fat phases structured by oleogel in culinary products has been evaluated in this study. In this contribution the oleogel application in bouillon cubes as model system for culinary products is discussed. Three different gelators (sunflower wax (SFW), a mixture of β-Sitosterol and γ-Oryzanol (SO) and ethylcellulose (EC)), at two concentration levels (5% and 10% (w/w)) each, were evaluated with respect to their physical properties, in the food matrix and application. The application of pure and structured canola oil (CO) was benchmarked against the reference, palm fat (PO). The assessment of the prototypes covered attempts to correlate the physicochemical analyses and sensory data. Organoleptic and analytical studies covered storage stability (up to 6 months) monitoring texture, color and fat oxidation. The results indicate that the substitution of palm fat by oleogel is essentially possible. The characteristics of the bouillon cubes are tuneable by gelator choice and inclusion level. Most importantly, the data show that the anticipated risk of intolerable effects of oxidation during shelf life is limited if antioxidants are used.BMBF, 01EA1806C, Kompetenzcluster Ernährungsforschung: NutriAct - Ernährungsintervention für gesundes Altern, Technische Universität BerlinTU Berlin, Open-Access-Mittel – 202

Wax‐Based Oleogels—Properties in Medium Chain Triglycerides and Canola Oil

The non‐triglyceride structuring of liquid oils, so‐called oleogelation, enables new and more beneficial product designs. Natural waxes have proven to be excellent oleogelators due to their wide availability and low inclusion levels. However, waxes vary greatly in their compositions and contain different proportions of major components: wax esters (WE), fatty acids (FA), fatty alcohols (FaOH), and hydrocarbons (HC). In this study six waxes (bees (BW)‐, sunflower (SFW)‐, ricebran(RBW), carnauba (CRW)‐, candelilla (CLW)‐, and sugarcane wax(SCW)) are selected to develop a pairwise assessment regarding the major components. Commercial canola oil, rich in minor and polar components, and medium‐chain triglycerides (MCT), as a “clean” saturated solvent, are used to elucidate the effect of solvent type on the gel forming behavior of 10% w/w oleogels. The gels are analyzed rheologically, penetronomically, microscopycally, and by calorimetry. It can be shown that the solubility and presence of polar minor components are crucial factors in oleogelation. Practical applications: Useful areas of application can be found in products with high proportions of saturated and trans fatty acids, a high potential of substitution, and can for instance include bakery‐, meat‐, culinary‐ and confectionary products

Effect of sprouting temperature on selected properties of wheat flour and direct expanded extrudates

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.TU Berlin, Open-Access-Mittel - 202

Enzymatic Modification of Granular Potato Starch Using Isoamylase—Investigation of Morphological, Physicochemical, Molecular, and Techno‐Functional Properties

Granular potato starch is modified using the debranching enzyme isoamylase. The modification is performed in aqueous suspension (40% w/w) at 35 °C by grading the volume (100, 250, and 400 µL/50 g of starch, 200 U · mL−1) of enzyme solution added. The starch products obtained are comprehensively investigated in terms of morphological (scanning electron microscopy), structural (X‐ray diffraction), thermal (differential scanning calorimetry), techno‐functional (solubility, hot paste viscosity, gel strength), and molecular properties (size exclusion chromatography‐multi angle laser light scattering‐differential refractive index detection). The granular integrity is basically preserved after modification and a molecular degradation predominantly of the amylopectin by debranching is proved. However, a slight reduction of the weight average molar mass of the amylose fraction is found too. In addition, the intended partial molecular degradation of the starch polysaccharides, the effect of the preparation procedure including washing with ethanol and grinding impacts several starch characteristics conspicuously.TU Berlin, Open-Access-Mittel – 202