المؤلفون: Eliasson, A. C.

مصطلحات موضوعية: Food Engineering, Amylose and amylopectin, Crumb structure, Falling number, Firmness, Retrogradation, Starch damage, Starch gelatinization, Starch granule size distribution, Water absorption

الوصف: Starch is the most abundant component in wheat flour, but has not traditionally been regarded as responsible for differences in quality between wheat varieties. In this chapter the role of starch in the baking process is described and examples on the role of starch during mixing, fermentation, and the oven step are given. The relevance of starch for baking performance is discussed, e.g., the setting of the crumb, and also the role of starch in the staling of bread. Factors that influence starch retrogradation are discussed in depth. Starch properties are described at the granule and molecular levels. Differences in amylose and amylopectin content, and the chemical properties of these components are discussed in relation to the baking process and to staling.

العلاقة: https://lup.lub.lu.se/record/4d0c4ef4-08f0-4dd8-822f-1c5e2d1afbb2Test; http://dx.doi.org/10.1016/B978-0-08-102519-2.00005-0Test; scopus:85126403344

الإتاحة: https://doi.org/10.1016/B978-0-08-102519-2.00005-0Test
https://lup.lub.lu.se/record/4d0c4ef4-08f0-4dd8-822f-1c5e2d1afbb2Test

المؤلفون: Fuentes, Catalina, Kang, In, Lee, Jangjae, Song, Dongsup, Sjöö, Malin, Choi, Jaeyeong, Lee, Seungho, Nilsson, Lars

المصدر: Analytical and Bioanalytical Chemistry; 411(16), pp 3665-3674 (2019) ; ISSN: 1618-2642

مصطلحات موضوعية: Food Engineering, Differential scanning calorimetry (DSC), Gravitational field-flow fractionation (GrFFF), Split-flow thin cell fractionation (SF), Starch granule

الوصف: Starch is one of the main carbohydrates in food; it is formed by two polysaccharides: amylose and amylopectin. The granule size of starch varies with different botanical origins and ranges from less than 1 μm to more than 100 μm. Some physicochemical and functional properties vary with the size of the granule, which makes it of great interest to find an efficient and accurate size-based separation method. In this study, the full-feed depletion mode of split-flow thin cell fractionation (FFD-SF) was employed for a size-based fractionation of two types of starch granules (corn and potato) on a large scale. The fractionation efficiency (FE) of fraction-a for corn and potato granules was 98.4 and 99.4%, respectively. The FFD-SF fractions were analyzed using optical microscopy (OM) and gravitational field-flow fractionation (GrFFF). The respective size distribution results were in close agreement for the corn starch fractions, while they were slightly different for the potato starch fractions. The thermal properties of FFD-SF fractions were analyzed, and the results for the potato starch showed that the peak temperature of gelatinization (T p ) slightly decreases as the size of the granules increases. Additionally, the enthalpy of gelatinization (ΔH) increases when the granule size increases and shows negative correlation with the gelatinization range (ΔT).

العلاقة: https://lup.lub.lu.se/record/1ef81a66-79cf-4d39-8d1d-3b9677114078Test; http://dx.doi.org/10.1007/s00216-019-01852-9Test; scopus:85065577145; pmid:31069435

الإتاحة: https://doi.org/10.1007/s00216-019-01852-9Test
https://lup.lub.lu.se/record/1ef81a66-79cf-4d39-8d1d-3b9677114078Test

المؤلفون: Matos, María, Timgren, Anna, Sjöö, Malin, Dejmek, Petr, Rayner, Marilyn

المصدر: Colloids and Surfaces A: Physicochemical and Engineering Aspects; 423, pp 147-153 (2013) ; ISSN: 0927-7757

مصطلحات موضوعية: Food Engineering, Double emulsions, starch granule, encapsulation, Pickering emulsions

الوصف: Double emulsions have potential applications in the food, cosmetic and pharmaceutical industries as vehicles for encapsulation and delivery of nutrients during food digestion or as drug release. The major drawback of this type of emulsions is that they are often difficult to stabilize. Particle stabilized emulsions, known as Pickering emulsions, show special features, such as being extremely stable with respect to coalescence. Starch granules have proved to be a suitable stabiliser for food grade Pickering emulsions. In this work, starch double W1/O/W2 Pickering emulsions were prepared and their encapsulation stability was studied as well as the impact of varying the lipophilic emulsifier (PGPR90) content and salt concentration in the W1 inner aqueous phase. Encapsulation properties were quantified by monitoring the release of a hydrophilic dye from the inner aqueous phase spectrophotometrically. Two double emulsion systems were studied, one with an inner aqueous phase with 0.1M NaCl and the other with 0.2M NaCl. The initial encapsulation efficiency was over 98.5% immediately after emulsification production. The encapsulation stability (ES) remained over 90% after 21 days for both systems studied, where 0.1 M NaCl W1 emulsion had a ES of 95.2% and the 0.2 M NaCl W1 emulsion had a ES of 91.1% respectively.

العلاقة: https://lup.lub.lu.se/record/3460941Test; http://dx.doi.org/10.1016/j.colsurfa.2013.01.060Test; wos:000316831200021; scopus:84874556413

الإتاحة: https://doi.org/10.1016/j.colsurfa.2013.01.060Test
https://lup.lub.lu.se/record/3460941Test

المؤلفون: Rojas, Carola

مصطلحات موضوعية: Electrical Engineering, Electronic Engineering, Information Engineering, Food Engineering, amylopectin, hydrodynamic radius, field flow fractionation, overlap concentration, minerals, enzymes, cassava, hydrolyses, glucose, maltose, sucros, amylase, hydrolyses kinetics, starch granule structure, radius of gyration, drying kinetics, heat transfer, high pressure homogenisation, mass transfer

الوصف: The objective of the present thesis was to understand how the quality and performance of dried cassava products could be developed by drying and other processing steps. This goal was achieved in several stages. First, a survey of the composition of six cassava varieties from Bolivia, was performed, which resulted in the report of chemical and mineral compositions of the tubers. The mineral compositions of the tubers were compared to the elemental composition of the soil in order to identify depleted and enriched elements. In a second step, an enzymatic assay for the determination of lower sugars in cassava was developed. This technique rendered it possible to measure the content of free glucose, maltose and sucrose in six varieties of cassava. The third step implied the development of a process for partial hydrolysis of non-gelatinized cassava starch. In this study, the kinetics of the enzymatic hydrolysis of raw cassava starch were described as a heterogeneous system, and the investigation involved leaching of amylose during starch granule swelling, and morphological characterizations of starch granules using SEM as well as light microscopy. Results included a model describing the kinetics of the enzymatic hydrolysis and which assumed a blocklet structure of the starch granule and reveals that the enzymatic attack occurs mainly at the interior starch-water interface of the granule. Fourth, a model describing the kinetics of the drying of cassava starch was put forward. From this investigation, a quasi steady state model was developed based on heat and mass transfer. Finally, the impact of high pressure homogenization of dissolved starch was studied, which involved the degradation and conformational changes of starch as caused by the process. The characterization was performed with AsFlFFF with MALS and RI detection. Upon high pressure homogenization, the molar mass, mean square radius and hydrodynamic radius were found to decrease. The process also induced an increase and scaling with size in the apparent ...

العلاقة: https://lup.lub.lu.se/record/1290138Test; urn:isbn:978-91-976695-5-9

الإتاحة: https://lup.lub.lu.se/record/1290138Test

المؤلفون: Larsson, Helena

مصطلحات موضوعية: Food Engineering, starch gel, gluten, water distribution, lipids, starch granule surface, starch content, mixing, ultracentrifugation, structure, rheological measurements, wheat flour dough, phase separation, ethyl(hydroxyethyl)cellulose, Food and drink technology, Livsmedelsteknik

الوصف: The thesis presents a rheological study on wheat flour dough, in relation to the structural influence of the different dough constituents, added components and mixing time. Rheological investigations have been focused on measurements at small deformations, including dynamic oscillation and stress relaxation, although complementing measurements have been performed in large deformation viscosity experiments. The dough (flour and water) accommodate two dispersed phases, air cells and starch granules. Due to the insolubility of gluten in water, starch granules and excess water (including solubles) can be considered to constitute a second aqueous phase in developed dough. This suggests that dough can be described as a phase-separated system. Ultracentrifugation of dough was demonstrated to provide a simple tool for studies of the separation properties of wheat flour dough. The advantage of this technique is that information about the components and possible interactions is obtained with only minor influence on the dough constituents. The separation properties were found to be influenced by dough water content, wheat variety, mixing time, and the presence of lipids and ascorbic acid. By studying the corresponding effect on the stress-relaxation modulus, further information useful for the interpretation of the rheological results was obtained. A difference in location of water in overmixed dough and dough mixed with excess amounts of water was found. The gluten phase was only capable of accommodating a certain amount of water (= 55%), independent of the dough water content. Prolonged mixing, however, influenced the water content of the separated gluten phase, i.e. more water was occluded with extended mixing. A considerable effect of starch content on the rheological properties of dough was demonstrated. It was also found that the influence of starch on the rheological properties increased with prolonged mixing. When the starch granule surface was modified, the rheological behaviour of the dough was influenced. This ...

العلاقة: https://lup.lub.lu.se/record/29112Test; other:ISRN: LUTKDH/TKL0-1030/1-80

الإتاحة: https://lup.lub.lu.se/record/29112Test