Spray-dried Starch Research Articles

A new pre-gelatinized starch preparing by spray drying and electron beam irradiation of oat starch

As a green and safe physical technology, irradiation is increasingly used to improve starch properties. In the study, oat starch was pre-gelatinized at 70 °C followed by spray drying. Subsequently, the spray-dried starch (SDS) was exposed to electron beam (e-beam) irradiation at different doses to obtain new pre-gelatinized starch. Spray drying caused a decrement in the ratio of long B3 chains and the molecular weight of starch. Spray-dried starch (SDS) slightly increased solubility and swelling power than native starch. When SDS was subjected to e-beam irradiation, its solubility and swelling power increased dramatically, but the pasting viscosities, gelatinization temperatures, apparent viscosity, storage modulus (G′) and lost modulus (G″) reduced. The depolymerization of starch molecules and the breakage of amylopectin chains might be responsible for changing the physicochemical properties of e-beam irradiated starch. These results showed that spray drying combined with e-beam irradiation would potentially produce new pre-gelatinized starch.

Production of spray-dried starch molecular inclusion complexes on an industrial scale

Pregelatinized maize starch and fatty acids were employed as test material to develop a process for the production of molecular inclusion complexes for nutritional and therapeutic purposes, using a pilot scale spray dryer. Structural and morphological characteristics of samples were assessed using X-ray diffractometry, scanning electron microscopy, differential scanning calorimetry and confocal laser scanning microscopy. Functional properties such as particle size distribution and apparent density were also determined. The results indicated that the complexes were effectively formed prior to drying and remained stable during spray-drying. Their degree of crystallinity was about 10–15% whereas their average particle size was 20–40μm and the tapped density was 0.25–0.50g/mL. The process was evaluated for being well suited for the production of starch complexes with sensitive to oxidation and thermal stability compounds having the appropriate functional properties.

Green isolation and physical modification of pineapple stem waste starch as pharmaceutical excipient

The waste of inedible parts of pineapple, particularly in tropical countries, contributes to environmental burden. This study aimed to utilize pineapple stem waste as a source of starch-based pharmaceutical excipient. The starch was isolated from pineapple stem waste using a simple process without applying harsh chemicals. The isolated starch (PSS) was then physically modified through gelatinization and spray drying to improve its physical properties. Starch characteristics were identified by FTIR, TGA, and XRD analysis. The SEM imaging showed morphological change with reduced surface roughness due to physical modification of the starch. Decreased crystallinity of modified starch (MPS) was confirmed by our XRD results: the peaks of A-type crystalline at 2θ of 13°, 15°, 18°, and 23° were present in PSS, yet mostly absent in MPS. Thermogravimetric analysis showed that MPS behaved differently from PSS and the degradation events occurred at lower temperature. When the starch was spray-dried without prior gelatinization process, the physicochemical characteristics of spray-dried starch resembled untreated starch. Moisture content in PSS (10.66%) decreased after gelatinization to 7.3%. Potential use of MPS was demonstrated by its powder flowability (Student’s t test, p < 0.05), swelling capacity (Student’s t test, p < 0.05), and compaction profile. In summary, our findings demonstrated that modified pineapple starch showed better physical characteristics and quite promising as a tablet binder and disintegrant.

Effect of spray-drying and extrusion on physicochemical characteristics of sweet potato starch.

This study aimed to understand the physicochemical characteristics of sweet potato starch following spray-drying and extrusion processes for desirable applications. Spray-dried starch showed formation of agglomerates and decreased in average granular size from 16.5μm of the native starch granules to 14.1μm. Spray-drying reduced the percentage crystallinity from 25.3 to 22.6% and showed a slight decrease in the molecular weight of amylopectin from 3.1 to 2.6 × 108 gmol-1. In addition, changes in the pasting and gelatinization properties, higher final viscosity (454.4 RVU), and less enthalpy change (8.73Jg-1) were reported after spray-drying. Thus, spray-drying resulted in partially gelatinized starch, which can be selected for making more viscous products. Extruded sweet potato starch displayed an amorphous structure, showed total loss of crystallinity, and significant reduction in molecular weight of amylopectin to 0.41 × 108gmol-1, reflecting complete gelatinization of starch granules during extrusion. Extruded starch showed significant changes in pasting properties, including a display cold viscosity (9.4 RVU). Therefore, extruded starch was suitable for products that require quick solubility and a low final viscosity. Thus, the spray-drying and extrusion processes produce sweet potato starches with particular characteristics that can be used for different and potential applications in industries.

Rheological properties of dough and quality of bread supplemented with emulsifying polysaccharides

The aim of present study was to evaluate the effects of emulsifying starches used as additives in breadmaking. In order to achieve this, the partial replacement (5-10%) of wheat flour with starch sodium octenyl succinate (OSA starch), pregelatinized starch sodium octenyl succinate (Pregel OSA starch) and hydrolyzed spray-dried starch sodium octenyl succinate (Hydrol OSA starch) was performed. The quality characteristics of obtained bread were compared to control wheat flour bread and bread containing 0.5% hydroxypropyl methylcellulose (HPMC). The obtained results indicated that addition of Pregel and OSA starches influenced the increase in water absorption, whilst addition of Hydrol OSA starch exhibited the opposite effect. Moreover, the addition of all chosen starches influenced the decrease in dough stability. On the other hand, the positive effects of implementation of emulsifying starches on specific volume and texture were observed, where Pregel OSA and OSA starch have expressed the highest effect.

Understanding the role of plasticisers in spray-dried starch

Amorphous thermoplastic starch (TPS) films were produced by compression moulding of solution spray-dried TPS powder and by direct solution casting. Oxidised potato starch was used as a feedstock for production of plasticised formulations containing glycerol or urea, or their combinations with maltodextrin (DE=19.1) as processing aid.The crystallinity index of freshly moulded films made from solution spray-dried powder was significantly lower than that for casted films. FTIR analysis showed that starch interacted in hydrogen bond formation with glycerol and urea plasticisers, reducing the glass transition temperature to 136°C and 106°C, respectively. Formulations containing maltodextrin did not show a Tg. Glycerol-plasticised and co-plasticised films immediately started to retrogradate in the presence of moisture, while urea based systems only showed slow recrystallization at the highest moisture exposure. In line with retrogradation behaviour, urea plasticised and co-plasticised films exhibited a more ductile behaviour, whereas glycerol based ones showed more brittle behaviour.

A Statistical Approach to Optimize the Spray Drying of Starch Particles: Application to Dry Powder Coating

This article describes the preparation of starch particles, by spray drying, for possible application to a dry powder coating process. Dry powder coating consists of spraying a fine powder and a plasticizer on particles. The efficiency of the coating is linked to the powder morphological and dimensional characteristics. Different experimental parameters of the spray-drying process were analyzed, including type of solvent, starch concentration, rate of polymer feeding, pressure of the atomizing air, drying air flow, and temperature of drying air. An optimization and screening of the experimental parameters by a design of the experiment (DOE) approach have been done. Finally, the produced spray-dried starch particles were conveniently tested in a dry coating process, in comparison to the commercial initial starch. The obtained results, in terms of coating efficiency, demonstrated that the spray-dried particles led to a sharp increase of coating efficiency value.

Mechanical properties and structure of swollen crosslinked high amylose starch tablets

Crosslinked high amylose starch (CLHAS) has been introduced as an excipient for controlled oral drug delivery. The kinetics of delivery is governed by the diffusion of the medication through a hydrogel matrix, which forms as water penetrates the CLHAS tablet. The formation of the gel from the compressed spray-dried starch powder comes from pseudo-crosslinking of particles by the self-assembly of amylose and amylopectin segments into double helices. Tablets reach equilibrium swelling after more than 24 h and contain about 200% water. They demonstrated nearly reversible non-linear viscoelastic properties. Under compression, water flows out and vice-versa for decompression suggesting a sponge-like behaviour. A series of tablets fabricated under increasing compression force in the dry state showed a decrease of wet equilibrium stiffness with increasing fabrication pressure. Scanning electron microscopy on freeze-dried tablets reveals a fine porous texture at the surface of the tablets, which forms, in the first minutes of water penetration. On the other hand the internal texture which develops over longer periods has much larger pores which account for the high equilibrium water content and the observed sponge-like behaviour.