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The synthesis and stimulating effects of isomalto-oligosaccharides from Chinese chestnut starch (CN-IMOs) on Lactobacillus proliferation were investigated in this paper. The synthesis process of CN-IMOs mainly consisted of liquefaction, saccharification and transglycosylation in sequence. The optimal liquefaction time with heat-stable α-amylase and CaCl 2 was 120 min, and the dextrose equivalent value of the liquefied slurry was 13.8. Saccharification was performed at 60 °C for 2 h by using a complex enzyme system comprising fungal α-amylase, β-amylase and pullulanase. The hydrolysate was then subjected to transglycosylation with α-transglucosidase for 20 h. The syrup contained 30.53% total CN-IMOs, and then was purified by 732 cation exchange resins (Na + ). The recovery rate and total content of it was 91.6% and 61.5%, respectively. Moreover, the proliferative effects of CN-IMOs, purified CN-IMOs (CN-IMOs-P), and commercial isomalto-oligosaccharides (IMOs-50) on Lactobacillus were observed in vitro. CN-IMOs-P was the best effective carbon source for Lactobacillus growth at an optimal dosage of 2.0% in the medium. All the results showed that Chinese chestnut could be a potential raw material for IMOs production, which was a new further processing area of chestnut utilization, and CN-IMOs-P can be explored as a novel prebiotic healthcare product for human gastrointestinal health.

The release of aldehydes from aqueous model systems containing starch or maltodextrins with different dextrose-equivalent (DE) values was evaluated using static headspace analysis. The patterns of aldehydes released differed significantly between starch and maltodextrin solutions with DE values of 4.0–7.0, 13.0–17.0, and 16.5–19.5. The release of most of aldehydes showed an increasing tendency according to DE values of maltodextrins. The release of most aldehydes decreased up to around 24 h, but then increased slightly at 48 h. In addition, the absorbance values of iodine-polysaccharide complexes and the particle sizes of the polysaccharides were measured to investigate the effects of hydrophobic regions and the intermolecular aggregation of polysaccharides on the releases of aldehydes. The absorbance values of iodine-polysaccharide complexes, which could be related to the internal hydrophobic regions, decreased in the maltodextrin and starch solutions as the equilibrium time increased up to 24 h, but then increased at 48 h. Also, the particle size increased gradually to 48 h, suggesting that the intermolecular aggregation of polysaccharides affects the release of aldehydes.

This study seeks to evaluate the influence of different dextrose equivalent values on the characteristics of emulsions assisted by ultrasound and lime essential oil microparticles. Four treatments were evaluated: whey protein concentrate (WPC), and blends of maltodextrin with dextrose equivalents of 5 (WM5), 10 (WM10) and 20 (WM20). The physicochemical properties of the emulsions (viscosity and droplet size) and dry powders, by spray drying (moisture content, water activity, particle size, surface oil, encapsulation efficiency, oil and limonene retention, x-ray diffraction, thermal and antioxidant activity analysis), were studied to measure the quality of the encapsulated materials. Maltodextrins with high DE values (10 and 20) had lower viscosities and consequently smaller droplet and particle sizes. The treatments showed significantly different and good retention for the majority compounds of the lime essential oil and maintained high antioxidant activity. Maltodextrin of DE 20 presented better significant oil retention values (77.6%) and encapsulation efficiency (83.3%). In conclusion, the degree of maltodextrin hydrolyzation can interfere with the physicochemical parameters of lime essential oil microparticles, observing the best results at higher DE values.

The purpose of this work was to study the influence of maltodextrins produced from chemically modified starches (stabilised, cross-linked, and double modified) on the stability and rheological characteristics of foam produced from egg albumin. A significant effect was found, related to the type of chemically modified starch used to produce the maltodextrins, on the stabilising properties of the latter and on the viscoelastic properties of the foam systems. Maltodextrins produced from distarch phosphate exhibited the best foam stabilising properties, while maltodextrins from acetylated starch had no favourable effect on the stability of the foam. Moreover, it was found that foam stability decreased as the dextrose equivalent (DE) value of the maltodextrin increased. The foams stabilised with maltodextrins exhibited viscoelastic properties, with domination of the storage modulus over the loss modulus, and behaviour similar to weak gels. The susceptibility of the foams to deformation was dependent on the type of maltodextrin and its DE value. The foam stabilised with the DE 6 maltodextrin produced from acetylated distarch phosphate was the most resistant to deformation, while foam with maltodextrin produced from acetylated starch was the least resistant to deformation.

Conjugation of whey protein isolate (WPI) and maltodextrin (MD, dextrose equivalent of 6) was achieved by dry-heating at an initial pH of 7.0, at 60 °C and 79% relative humidity, with WPI: MD6 ratio of 1:1, for up to 24 h. Conjugation was achieved with limited development of colour and advanced Maillard products on 24 h of heating. Conjugation increased the protein solubility at pH 4.5, by 7.1–8.5%, compared to the unheated and heated WPI controls. Conjugation of WPI with MD6 enhanced the stability and retention of clarity in protein solutions heated at 85 °C for 10 min with 50 mM added NaCl.

Concentrated mate (CM) obtained by nanofiltration, which is a rich source of phenolic compounds, was microencapsulated by spray drying using three different DE (dextrose equivalent)-values of maltodextrin: DE10.2 (M10), DE15.2 (M15) and DE18.6 (M20). A sample of CM with no addition of maltodextrin was also spray dried and denominated as Control. All the samples were characterized in relation to their yield, phenolic compounds, antioxidant activity, moisture content, water activity, dissolution, hygroscopicity, color, SEM particle microstructure, and thermal properties. The storage stability of the microcapsules was investigated at three different storage temperatures (5 °C, 25 °C and 45 °C) for 90 days. The M10 sample showed higher drying yield and better results for dissolution, hygroscopicity, moisture content and thermal properties than the M15 and M20 samples. However, the DE-values of the maltodextrin used as wall material had no effects on the total phenolic content or on the antioxidant activity of the microcapsules. In comparison to maltodextrins DE15.2 (M15) and DE18.6 (M20), maltodextrin DE10.2 (M10) produced more stable microcapsules, and thus was considered to be the most effective wall material for stabilizing the phenolic compounds and antioxidant activity of CM.

Summary A semi-industrial spray drying process of chokeberry juice concentrate using maltodextrin was analysed. The influence of the content and dextrose equivalent (DE) of maltodextrin, inlet air temperature and rotary disc atomiser speed was studied on the physicochemical properties of the obtained powders. The size and structure of the powder particles, bulk density, moisture content, flowability, yield and total polyphenol content were analysed. An increase in carrier content from 50% to 70% caused a 4.9% increase in total polyphenol retention, better flowability (Hausner ratio decrease of 0.17) and greater yield of the powder (60%). An increase in the drying temperature (150–170 °C) caused larger particle size and improved powder flowability but also resulted in greater loss of total polyphenols. A decrease in rotary atomiser speed (11 000–15 000 rpm) had a moderate influence on particle size and improvement in flowability but had no effect on polyphenol retention. Changes in the DE (8–22) of maltodextrin as a carrier indicated a moderate growing dependence on particle size and worse flowability.

The objective of the study was the kinetic modelling of the shelf-life of osmotically pre-treated fish during refrigerated and super-chilled storage. Fresh gilthead seabream (Sparus aurata) fillets were treated for 0–360 min at 15 °C in osmotic solutions 50:5 high dextrose equivalent maltodextrin:NaCl/100 g (HDM), 40:10:5 HDM:trehalose:NaCl/100 g (HDM + treh) and 40:10:5 HDM:glucosamine:NaCl/100 g (HDM + gluc). Water loss, solid gain, salt content and water activity were monitored throughout treatment. Slices untreated and osmotically pre-treated for 45 min were aerobically packed and stored isothermally at 15, 10, 5, 2.5, 0, −1 and −3 °C. Quality assessment was based on microbial growth (total viable count, Pseudomonas spp., Brochothrix thermosphacta, Enterobacteriaceae spp., H2S-producing bacteria, lactic acid bacteria, yeasts and moulds), total volatile nitrogen (TVB-N), lipid oxidation (TBARs) and sensory scoring. Quality indices were kinetically modelled and temperature dependence of quality loss rates was modelled by Ratkowsky equation. Osmotic pre-treatment led to significant shelf-life extension of fillets, in terms of microbial growth, chemical changes and organoleptic deterioration. The pre-treatment with the alternative solutes led to depression of the freezing point (−1.8, −2.6, −3.2 and −3.5 °C for the untreated samples and the osmotically pre-treated with HDM, HDM + treh and HDM + gluc, respectively). TVB-N values were higher in untreated samples, followed by osmotically treated fillets, mainly at higher storage temperatures (i.e. 10 and 15 °C). Based on the mathematical models for sensory evaluation scoring, the shelf-life was 12, 19, 22 and 22 days at 0 °C for untreated and osmotically pre-treated with HDM, HDM + treh and HDM + gluc fish slices, respectively, while the respective values at −3 °C were 21, 35, 38 and 38 days. The alternative solutes had no significant effect on the quality and shelf-life of pre-treated fish fillet during storage at refrigerated conditions.

Maltodextrin is a hydrolysate of cornstarch and has been widely used in the food industry associated with sucrose. The addition of starch can increase the cariogenic potential of sucrose; however, there are sparse data regarding the cariogenicity of sucrose associated with maltodextrin. Therefore, the aim of this study was to test in situ if maltodextrin could increase the cariogenic potential of sucrose. This was an in situ, randomized, crossover, split-mouth, and double-blind study. Volunteers wore palatal appliances containing bovine enamel blocks for 2 periods of 14 days. They dripped the following solutions on the enamel blocks 8 times per day: deionized distilled water (DDW), maltodextrin (M), sucrose + maltodextrin (S+M), or sucrose (S). At the end of each experimental period, biofilms were collected and analyzed for microbiological (mutans streptococci, lactobacilli, and total microorganisms counts) and biochemical (calcium, inorganic phosphate, fluoride, and insoluble extracellular polysaccharides concentrations) compositions. The enamel demineralization was assessed by microhardness. Treatments S and S+M resulted in a lower inorganic composition and higher concentration of insoluble extracellular polysaccharides in the biofilms, and higher enamel mineral loss compared to DDW and M. It can be concluded that the cariogenic potential of sucrose is not changed when this carbohydrate is associated with maltodextrin (dextrose equivalent 13-17).

There is increasing interest in developing food-grade coenzyme Q 10 (CoQ 10 ) ingredients for functional food formulations. This paper reported a spray-drying microencapsulation of CoQ 10 (in olive oil) using different food-grade biopolymers [soy protein isolate (SPI), pea protein isolate (PPI), defatted milk powder and octenylsuccinic anhydride-modified starch (OSA)] as the emulsifiers and wall materials, with the aim to improve its water solubility, stability and bioaccessibility. To improve the microencapsulation, maltodextrin (with a dextrose equivalent value of 16) was blended with the emulsifiers to produce the spray-dried microencapsulates. The type of proteins affected their physicochemical characteristics, including particle size, surface hydrophobicity and ξ -potential, which accordingly led to the differences in characteristics of the formed emulsions, e.g. droplet size and distribution profile, flocculated state of droplets, stability against coalescence and creaming, as well as interfacial protein concentration. All the microencapsulate preparations exhibited high encapsulation efficiency and good redispersion and/or dissolution behavior, though the encapsulation efficiency and dissolution behavior varied with the type of applied emulsifiers. The better encapsulation efficiency and dissolution behavior were largely related to the higher interfacial emulsifier concentration of the corresponding original emulsions. Furthermore, the microencapsulation remarkably improved the UV- or heat- stability, as well as the in vitro bioaccessibility of CoQ 10 . The improvement also distinctly varied with the type of applied emulsifiers. The results suggest that the spray-drying microencapsulation is an effective technique to improve the low water solubility and bioavailability of CoQ 10 , however, the choice of emulsifiers or wall materials is important for the optimization of the CoQ 10 encapsulation.

Starch saccharification is a key step in the industrial production of syrups. A two-step saccharification of raw corn starch at high concentration (45%, w/w) using granular starch hydrolyzing enzyme (GSHE) was investigated to improve the efficiency of this process. The results showed that the two-step saccarification (reaction at 65 °C for 30 min, followed by reaction at 70 °C for 90 min) was more effective than a single-step saccarification involving reaction at 65 °C for 120 min. After saccharification, both the glucose content and dextrose equivalent (DE) value were 10% greater using the two-step saccharification than using a single-step saccharification. Assessing the mechanism indicated that the reduction in peak viscosity of the starch slurry was more obvious using the two-step saccharification, the water activity was higher, and the mobility of water was stronger. Thus, the two-step saccharification offers great advantages in the production of syrups using granular starch hydrolyzing enzyme.

A series of modified poly(urethane-urea) carriers for immobilization of maltogenase from Bacillus stearothermophilus were presented. Poly(urethane-urea) microparticles (PUU) from poly(vinyl alcohol) and isophorone diisocyanate were modified with ethylenediamine, glutaraldehyde, trichlorotriazine and gold nanoparticles (AuNPs). Covalent attachment of enzyme to carrier via active isocyanate, aldehyde or aromatic chlorine group or electrostatic adsorption to AuNPs was performed. Maximal surface area (218.3 m2/g) was estimated for PUU microparticles modified with ethylenediamine and decorated with AuNPs. The high efficiency and yield of enzyme immobilization onto PUU-EDA/AuNPs were determined. Properties of maltogenase immobilized onto PUU carriers were compared to crosslinked enzyme aggregates from maltogenase (CLEA-maltogenase). The determined values of KM were 21.29 mM, 22.46 mM and 61.72 mM for soluble, CLEA-maltogenase and immobilized onto PUU-EDA/AuNPs, respectively. Hydrolysis of wheat starch catalyzed by immobilized maltogenase in continuous mini-reactor was more effective in comparison to CLEA-maltogenase; obtained dextrose equivalent was 28.9% and amount of maltose was 26.6%.

The use of lemongrass oil as food preservative present great potential, however it has high volatility and intense aroma, making them limited to be used as food additives. Microencapsulation processes become interesting alternatives to overcome these issues. This work investigated the influence of the partial replacement of gum arabic by modified starches on the microencapsulation of lemongrass oil as core material. Gum arabic and its combinations with modified starches: cassava and corn maltodextrins with different dextrose equivalent (DE) and octenyl succinic anhydride modified starch (OSA-starch) were studied. The emulsions were spray dried at controlled temperature of 170 °C. The evaluated parameters particles solubility, moisture content, and oil composition did not showed significant differences among the treatments. Replacement of gum arabic by maltodextrin DE20 and OSA-starch resulted in higher wetting times. Oil retention was increased (81.2%) when gum arabic was replaced by OSA-starch; the treatment without substitution, with only gum arabic had 67.5% of oil retention. Application of OSA-starch in association with gum arabic in microencapsulation by spray drying of lemongrass oil presented greater potential to be used due to its higher oil retention. Polymer blends should be assessed since they present advantages over individually applied polymers. Although maltodextrins show some differences compared to the treatment with only gum arabic, it may also be a viable alternative because of its lower cost.

El objetivo fue determinar el efecto de la aplicación de la enzima Celulasa fúngica en las cáscaras de plátano de seda (Musa paradisiaca) para la obtención de jarabe glucosado. Se estudió la hidrólisis enzimática de las cáscaras de plátano de seda al 30 % (p/v) a una temperatura constante de 50 °C. Las variables independientes para controlar fueron la Concentración de la enzima Celulasa fúngica (0,5 %, 1 % y 1,5 % p/v) y el Tiempo de hidrolisis (18, 24 y 30 horas). Las variables dependientes fueron el porcentaje de Azúcar Reductor y el porcentaje de Equivalente de Dextrosa (D.E.) de las muestras hidrolizadas enzimáticamente. El diseño experimental fue completamente al azar con modelo factorial 32. Se obtuvo jarabes glucosados a partir de cáscaras de plátano de seda por la hidrólisis enzimática de la Celulasa fúngica. Los mayores porcentajes de Azúcar Reductor y de Equivalente de Dextrosa se presentaron en la Concentración de Celulasa al 1,5 % (p/v) durante un Tiempo de hidrolisis de 30 horas con valores promedio de 15,5 % de porcentaje de Azúcar Reductor y de 30,9 % de porcentaje de Equivalente de Dextrosa. En la hidrólisis enzimática con Celulasa fúngica al 1,5 % (p/v) y 30 horas se obtuvo un producto de mayor valor agregado, se definieron las condiciones de operación y las etapas del proceso que deberían ser adaptadas para la producción de jarabe glucosado a partir de cáscaras de plátano (Musa paradisiaca). The objective was to determine the effect of the application of the fungal cellulase enzyme on the silk banana peels (Musa paradisiaca) to obtain glucosed syrup. The enzymatic hydrolysis of banana shells at 30% (w / v) was studied at a constant temperature of 50 ° C. The independent variables to be controlled were the concentration of the fungal cellulase enzyme (0.5%, 1% and 1.5% w / v) and the hydrolysis time (18, 24 and 30 hours). The dependent variables were the percentage of Reducer Sugar and the percentage of Dextrose Equivalent (D.E.) of the enzymatically hydrolysed samples. The experimental design was completely randomized with factorial model 32. Glucosed syrups were obtained from silk plantain hulls by the enzymatic hydrolysis of the fungal cellulase. The highest percentages of Reducer Sugar and Dextrose Equivalent were presented in the Cellulase Concentration at 1.5% (w / v) during a hydrolysis time of 30 hours with average values ​​of 15.5% of reducing sugar percentage and 30.9% of percentage of Dextrose Equivalent. In the enzymatic hydrolysis with fungal cellulase at 1.5% (w / v) and 30 hours a higher value-added product was obtained, the operating conditions and the process steps were defined that should be adapted for the production of glucosed syrup from of banana peels (Musa paradisiaca).

Enzymes as additives in starch processing are reviewed. Properties and compositions of starch hydrolyzates from cereals and tubers, as well as the degree of hydrolysis of exogenous enzymes and crude enzymes produced from malted grains, where enzymes acted as additives in starch processing, are discussed. Enzyme actions in the food industry, especially in bread making, beer production, and cheese and syrup production are reviewed and presented. This chapter covers hydrolysis of both starch and flours using crude enzymes, exogenous starch-degrading enzymes, and the nature of substrate along with the properties of these products as well as the effectiveness of multiple crude enzyme applications compared to single crude enzyme applications. Extensive discussion is on the relationship between dextrose equivalent (DE) and viscosity, sugar spectra/profile, and the effect of the source of substrate on the type and nature of sugars obtained in the starch hydrolyzates.

Gluten-free beer could be produced with rice, although the latter would primarily serve as adjunct in combination with barley malt in today’s brewing. However, the recent growing realisation of the potential and applications of rice malt for brewing an all-rice malt beer through varying malting conditions cannot be overlooked. In this study, therefore, the characteristic changes in malt, wort, and beer from different Nigerian rice varieties (FARO 44, FARO 57, NERICA 7) as influenced by varying malting conditions (steeping duration (18, 24 and 30 h), germination periods (2, 3 and 4 days) and kilning temperatures (50 and 55 °C)), were investigated. Rice (grain) samples were examined by thousand kernel weight (TKW), germinative energy (GE), germinative capacity (GC), and degree of steeping (DoS). To ensure that rice wort/beer with unique beer style and enhanced attributes, comparable to barley wort/beer is produced, malting conditions that produced rice malts with peak diastatic power (DP), cold water extract (CWE), and hot water extract (HWE) were selected. Peak DP, CWE and HWE were obtained at FARO 44 (18 h steeping, 3 days germination, 55 °C kilning (S18G3K55°)), FARO 57 (30 h steeping, 2 days germination, 50 °C kilning (S30G2K50°)) and NERICA 7 (24 h steeping, 3 days germination, 55 °C kilning (S24G3K55°)). Selected malts were further tested for moisture content, total nitrogen, malt yield and malting loss and subsequently progressed to wort and beer production. Wort’s pH, total soluble nitrogen (TSN), brix, kolbach index (KI), free amino nitrogen (FAN), dextrose equivalent (DE), original extract (OE) and sugar profile were determined, as well as beer’s pH, colour, apparent extract (AE), alcohol by volume (%ABV), turbidity and sensory attributes. Rice grain varied significantly (p < 0.05) in TKW, GE, GC and DoS across varieties. Despite wort’s pH, TSN, DE, OE as well as beer pH, colour, AE and turbidity resembling (p > 0.05) across varieties, wort’s brix, KI, FAN, sugar profile as well as beer’s %ABV, differed significantly (p < 0.05). Sensory attributes of appearance, colour, mouthfeel, and overall acceptability in beer differed noticeably (p < 0.05), except for aroma and taste (p > 0.05). Overall, the rice beer, though very slightly hazy, represented a pale yellow light lager, which is indicative of its peculiar beer style. Besides increased DP and enhanced hydrolysis, varying malting conditions of current study could serve as a pathway of reducing the cost of exogenous (commercial) enzymes or barley malt imports, together with decreasing barley’s dependency for brewing in the tropics.

Red cabbage anthocyanin-rich extract (RCA) was encapsulated by mixtures of maltodextrin dextrose equivalent 20 (MD20) and arabic gum (AG) combined at various ratios using drum drying technique. Encapsulation efficiency ranged from 93.65 ± 1.80 to 98.85 ± 0.32%, with the highest value achieved by MD20:AG at 20:80 ratio (MD20:AG 20:80). The solubility of all encapsulates was over 90%. The moisture contents (3.40%–4.66%) and water activities (0.313 ± 0.001–0.361 ± 0.003) were low. The highest anthocyanin content (42.26 ± 0.58 mg C3G E/100 g DW) had RCA encapsulated by MD20:AG 20:80. X-ray diffraction revealed a crystalline-mixed amorphous structure. The crystalline phase increased with an increase of AG ratio. Scanning electron microscopy (SEM) analysis identified the finest particles in MD20:AG 80:20 encapsulated RCA. Fourier transform infrared spectroscopy (FTIR) analysis revealed a broken glass structure and shriveled surfaces of all particles. Based on physico-chemical properties and morphological characteristics, the MD20:AG 20:80 RCA encapsulate was selected for application in food. An addition of encapsulated RCA (10, 20 or 30 g/kg product) to a native Thai dessert ‘Aluar” increased its shelf-life and antioxidant capacity, lowered acidity, lipid oxidation and spoilage, successfully increasing its overall quality.

Stickiness of sugar solutions causes problems in various food products and operations. In this study, the effects of glucose syrup type (dextrose equivalent) and crystalline particles on stickiness of sugar solutions with water contents from 10 to 20% were determined. Four different corn syrups with varying dextrose equivalence (DE) were used to determine the effects of polysaccharide distribution on sugar syrup stickiness. The effects of particles (zirconium oxide beads (Zr2O3), fondant sucrose and granular sucrose crystals) on the surface were then evaluated to gain a better understanding of their role in reducing syrup stickiness. Stickiness was measured as tack force and work of adhesion with a texture analyzer and correlated with water content and glass transition temperature (Tg). Both tack force and work of adhesion increased to a maximum as moisture content decreased from 20% down to between 11 and 13%. Below this water content, work of adhesion decreased as syrups underwent a transition from cohesive to adhesive failure. Similar behavior was shown for T-Tg. In general, lower DE caused a reduction in both tack force and work of adhesion without a significant change in Tg. Particles at the surface, regardless of their size or origin, decreased stickiness approximately linearly with increasing surface coverage, verifying the hypothesis that a reduction in the surface area of amorphous sugar in contact with the probe causes a direct reduction in stickiness. Stickiness of a partially-crystalline coating layer was correlated to moisture content and the extent of surface coverage of particles.

Amylose granules hydrolyzed with 2 M hydrochloric acid for various periods of time were used to prepare amylose nanoparticles through ethanol precipitation. Value of dextrose equivalent, viscosity average molecular weight and molecular chain length distribution of the acid hydrolyzed amylose granules were determined. The precipitated amylose nanoparticles were characterized by using dynamic light scattering and X-ray diffraction. Results showed that, after 48 h acid hydrolysis, viscosity average molecular weight of amylose decreased from 3.35 × 105 to 0.336 × 105 and the amylose macromolecular chains with DP > 1000 were cut into short ones. The short chain sugar molecules derived from the acid hydrolysis were not involved in the ethanol precipitation or incorporated into the precipitated amylose nanoparticles. The length and quantity of the residual amylose macromolecular chains after the acid hydrolysis were the main factors to influence size and crystallinity of the precipitated amylose nanoparticles.

The use of acid hydrolysis to convert starch into dextrose can be difficult and time-consuming. The process requires high acidic medium and temperature which tends to contaminate the end-product hydrolysate. Therefore, this research was carried out to obtain optimum conditions necessary to produce a high and quality Dextrose Equivalent by varying the initial starch concentration and acid volume. The mass of corn and cassava starch and the total hydrochloric acid volume used for the hydrolysis ranged from 100 to 400 g and 1-3 liters respectively. The results showed that the optimum conditions for hydrolyzing the two starch types to Dextrose were within a temperature range of 100°C-120°C, 12 w/w% starch concentration, 4 atmospheric pressure and 30 minutes operating time. The optimum conditions produced a Dextrose Equivalent of 79.80% and 78.66% for cassava and corn starch respectively. The amount of dextrose produced in the process is a function of temperature, pressure, acid volume, operating time and initial starch concentration. Experimental results also confirmed an increase in pH of the hydrolysate with a temperature rise, and this influenced the Dextrose quality. The outcomes provided new findings to complement existing outcomes on how initial starch concentration and acid volume affect Dextrose Equivalent by acid-type hydrolysis.

The demand for the application of resistant starch as a functional ingredient is growing, thus, the analysis of its structural, thermal and digestibility properties can help food producers in optimizing industrial applications. The effect of autoclaving (120 °C/30 min)-debranching (2% pullulanase/50 °C) time (1 or 11 or 21 h) and retrogradation temperature (4 or 32 or 60 °C/24 h) on sweet potato starch fractions were studied. Further, the functional, pasting, thermal and structural properties of gelatinized, enzyme-hydrolyzed and retrograded (GEHRS) were also investigated. All the treated starches exhibited a dextrose equivalent value ranging between 3.70 and 5.30%. Debranching of starch at 50 °C for 21 h and retrogradation at 4 °C yielded 63% of RS. Results showed that most of the functional properties had been enhanced in GEHRS. GEHRS registered a lower pasting profile, higher gelatinization temperatures and displayed the B + V diffraction pattern with an increased crystallinity. The SEM of debranched starches showed rough plate-like surfaces with irregularly shaped structures. The study concludes that pullulanase debranching of sweet potato starch at 50 °C for 21 h and subsequent retrogradation at 4 °C produce a higher amount of resistant starch in sweet potato starch.

In this study, we report the direct precipitation of nano-HA in the present of maltodextrins with the different dextrose equivalent (DE) values in the range of 10–30. Characterization of the obtained samples, using X-ray diffraction and Fourier transform infrared spectrophotometry, indicated that the presence of maltodextrins, with the different DE values, does not affect the phase composition and structure of the obtained composites. Morphology studies of the samples, using field emission scanning electron microscope and transmission electron microscope, revealed that maltodextrin has obvious effect on the size, shape, and morphology of hydroxyapatite nanoparticles. In particular, in studied DE range, maltodextrin DE 28–30 with dominant structure of debranched chain is the most preferable choice to obtain the composite with highly dispersed nanoparticles. In vitro assay on pre-osteoblast MC3T3-E1 cells demonstrated the ability of the composites to stimulate alkaline phosphatase activity and mineralization during differentiation of the cells.

This study investigated the impact of glucose polymer chain length on heat and physical stability of milk protein isolate (MPI)-carbohydrate nutritional beverages containing 8.5% w/w total protein and 5% w/w carbohydrate. The maltodextrin and corn syrup solids glucose polymers used had dextrose equivalent (DE) values of 17 or 38, respectively. Increasing DE value of the glucose polymers resulted in a greater increase in brown colour development, ionic calcium, protein particle size, apparent viscosity and pseudoplastic rheological behaviour, and greater reduction in pH, hydration and heat stability on sterilisation at 120°C. Incorporation of glucose polymers with MPI retarded sedimentation of protein during accelerated physical stability testing, with maltodextrin DE17 causing a greater reduction in sedimentation velocity and compressibility of sediment formed than corn syrup solids DE38. The results demonstrate that chain length of the glucose polymer used strongly impacts heat and physical stability of MPI-carbohydrate nutritional beverages.

Slurries of canna starch treated with or without α-amylase were heated at 60 °C to investigate the mechanism of thermal and enzymatic degradation and the effects of these processes on the ultrastructure of starch residues. For this purpose, solid-state 13 C CP/MAS NMR, X-ray diffraction (XRD), and small angle X-ray scattering (SAXS) were used to estimate the short- and long-range orders within the structure. Crystal stabilization was observed in both samples of thermally degraded canna starch (TDCS) and enzymatically degraded canna starch (EDCS), and the critical time for the formation of double helical crystals was 3 h for thermal degradation and 5 h for enzymatic degradation. With longer times, imperfect sub-crystal started prevailed. The results showed that when degradation occurs, the crystal lamellae compact, as indicated by a higher crystal density in the structure of EDCS. Moreover, the relationship between crystalline weight and volume fraction as well as short-range and long-range orders were also investigated and found correlate well with each other.

Anthocyanins are sensitive compounds and easily degradable when exposed to light, oxygen and pH values higher than 7. In this context, to better take advantage of the functional properties and to increase the stability of these pigments, this work aimed to obtain extracts from jussara (Euterpe edulis Martius) pulp and to produce spray dried microparticles. Maltodextrin with different dextrose equivalent values (10, 20 and 30 DE), gum Arabic and the combination of the maltodextrin 10 DE with gum Arabic (proportions 25:75; 50:50 and 75:25) were evaluated as carrier agents. Microparticles were characterized in relation to the moisture content, water activity, hygroscopicity, glass transition temperature, particle size distribution, color, anthocyanin content and profile, antioxidant capacity and microstructure. Microparticles showed high anthocyanin retention, above 88%. Anthocyanin profiles were similar to the microparticles and jussara extract and two anthocyanins identified were cyanidin 3-rutinoside and cyanidin 3-glucoside. Carrier agents influenced on the microparticles characteristics; maltodextrin 30 DE presented higher hygroscopicity and the lowest glass transition temperature. Microparticles produced with maltodextrin 10, 20 and 30 DE have shown smoother spherical surface than particles constituted with gum Arabic. Homogeneous distribution of anthocyanin in the particle structure was observed by confocal microscopy analysis.

Freezing modifies microstructures and affects physico-chemical changes during thawing of foods. This study investigated impact of freezing temperature (−20 °C, −50 °C and −90 °C) and controlled freezing process, and dextrose equivalent (DE5, DE15 and DE18) of maltodextrin (MD) on microstructure, mechanical and structural changes (shrinkage and recrystallization) of freeze-thawed MD-agar gels. Shrinkage and turbidity of matrices were dependent on freezing conditions and microstructures of solids. X-ray tomography revealed that low cooling rate formed large ice crystals contributed to thicker solid networks. However, a slow cooling to a supercooled region (∼0 °C to −1 °C) followed by a quench cooling caused rapid ice nucleation and inhibited ice growths resulting in only few clusters of large ice with a high number of fine ice crystals. Raman spectra indicated amorphous–crystalline transition (recrystallization) of gel components particularly maltodextrin after thawing in low DE systems which increased gel turbidity and subsequently accelerated shrinkage. Lower temperature freezing gave thinner but higher connectivity of solid networks providing higher mechanical strength and delayed recrystallization of maltodextrin which primary increased firmness values. The results indicated that the manipulation of freezing process in achieving small ice crystals effectively reduced structural changes attributing to recrystallization of high DE maltodextrin components in gel systems.

Rice wine was made from broken rice (by-product of rice processing), which was hydrolyzed by amylolytic enzymes, producing syrup with high content of dextrose equivalent (51.04% DE). The must presented 164 g/L of glucose (15 oBx) and pH of 2.67 was fermented for 22 h at 25C by Saccharomyces cerevisiae. Fermented alcoholic (rice wine) reached yield value of 74.94% (Y1), 91.71% (Y2) and productivity (Pp) of 2.85 g/Lh in alcohol, with alcohol concentration of 62.8 g/L, 28.0 g/L of glucose, 2.5 °Bx and pH of 3.0. The kinetic parameters – Yp/s 27.75%, μN 0.008 h−1, gt 3.99 h, PN 0.13 logUFC/mLh – were determined. The wine contained a total of 11 volatile compounds identified by GC-FID, 7 alcohols (methanol, ethanol, n-propanol, n-butanol, iso-amylic alcohols, iso-butanol and glycerol), 2 aldehydes (acetaldehyde and acetol), 1 ester (ethyl acetate) and 1 ketone (acetone). Practical Applications The product obtained showed potential features to be employed not only as alcoholic beverage, but also as a raw material in the production of other products such as vinegar, adding value to rice processing. Considering the production outlook and the amount of generated by-product, it is a lower cost substrate for such application. The characterization of volatile flavor compounds might be made use not only for a better understanding of this new-type product, but also for the further utilization in other wine or alcohol production.

In this research, date syrup powder was produced using a twin drum dryer. Maltodextrin with dextrose equivalent of 19, as an antiplasticizer, was added to date syrup at various concentrations (30, 40, 50 and 60%, dry basis of date syrup) to improve its drying properties. Some physicochemical properties of the powders including degree of caking, density, color, glass transition temperature and sorption isotherms were studied and compared. Powder density, lightness and glass transition temperature increased with maltodextrin level. However, “a” color value and degree of caking decreased as maltodextrin increased. Moisture sorption isotherms were obtained at 5–60 °C and the data were modeled to BET, GAB, and Peleg models and GAB and Peleg were found as suitable models to fit moisture sorption data. Monolayer moisture content decreased with maltodextrin level from 0 to 60% as calculated from BET and GAB models. All date syrup powders showed type III isotherms similar to that of high-sugar foods. Maltodextrin acted as antiplasticizer in date syrup drying and date syrup powder of low caking property was produced successfully.

The effects of total protein/total solid ratio (TP/TS) and pH on the spray drying process and rehydration properties of soy powder were investigated. The results showed that a decrease in the pH of the feed from 7 to 4 resulted in an increase of particle size, wettability index (WI), dispersibility index (DI) and water content (WC) of soy powder. In contrast, the solubility index (SI) and viscosity decreased, presumably due to a decrease of surface charges near the isoelectric point of soy protein leading to the formation of insoluble complexes at pH 4. WC and DI of the powder obtained by spray drying decreased as TP in the powder increased, regardless of the dextrose equivalent (DE) of the maltodextrin (MD). The latest affects the DI and WC in the powder; with increasing DE, WC and the energy cost to manufacture the powder decreased, whereas DI slightly increased.

Sour cassava starch is a naturally modified starch produced by fermentation and sun drying, achieving the property of expansion upon baking. Sour cassava starch' bakery products can be prepared without the addition of yeast and it is gluten free. The fermentation process associated with this product has been well studied, but the wastewater, with high acidity and richness in other organic compounds derived from starch degradation, requires further investigation. In this study, the structure of solids present in this residue was studied, seeking to future applications for new materials. The solids of the wastewater were spray dried with maltodextrin (MD) with dextrose equivalent (DE) of 5 and 15 and the structure of the powder was evaluated by scanning electron microscopy. A regular structure with a network arrangement was observed for the dried material with MD of 5 DE, in contrast to the original and fermented starches structure, which suggests a regular organization of this new material, to be studied in future applications. RESUMO: O polvilho azedo é um amido naturalmente modificado, produzido por fermentação e seco ao sol, atingindo a propriedade de expansão. Produtos de panificação a partir do polvilho azedo podem ser preparados sem a adição de leveduras e são livres de glúten. O processo fermentativo tem sido exaustivamente estudado, mas as águas residuais com elevada acidez e ricas em compostos orgânicos derivados da degradação do amido, requerem futuros trabalhos. Neste estudo, a estrutura dos sólidos presentes nesse efluente foi estudada vislumbrando futuras aplicações para estes novos materiais. Os sólidos contidos na água residual foram secos em spray dryer com maltodextrina (MD), com equivalente de dextrose (DE) de 5 e 15. A estrutura das partículas foi observada por microscopia eletrônica de varredura. Uma estrutura regular com arranjo em rede foi observada para o material seco com MD DE 5, em características que diferem das estruturas do amido nativo e do amido fermentado, o que sugere uma nova e regular organização estrutural com futuras aplicações a serem determinadas.

Purple sweet potatoes were dehydrated with maltodextrin with different dextrose equivalent (DE) values of 4-7, 13-17, 16.5-19.5, and 17-20. Maltodextrin was used as a molecular press dehydrating agent. The molecular dehydration rate of the purple sweet potatoes increased over time. As the DE of maltodextrin increased, the moisture content after 12 h of dehydration decreased from 65.7% to 40.8, 36.1, 34.9, and 28.6% for DE values of 4-7, 13-17, 16.5-17.5, and 17-20, respectively. Additionally, total phenolic content, anthocyanin, and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activities decreased as the DE value of maltodextrin increased. While maltodextrins with DE values of 16.5-19.5 and 17-20 effectively dehydrated the purple sweet potatoes, total phenolic, anthocyanin, and DPPH radical scavenging activities were lowered during dehydration. The DPPH radical scavenging activities correlated to both the total phenolic content (r 2 =0.96) and anthocyanin contents (r 2 =0.95) of the purple sweet potatoes. These results indicate that the purple sweet potatoes were effectively dehydrated with maltodextrin whose DE values ranged 16.5-20, although there were losses in the total phenolic and anthocyanin contents.

Glycerol monooleate (GMO) improves creaming stability in protein-stabilised emulsions but is unsuitable for direct aqueous applications due to its low solubility in water. Encapsulation could transform waxy solid GMO into a water-dispersible powder. This study assessed spray-drying to produce instantised GMO powders, and investigated emulsion formulation (GMO concentration (33.6%, 47.0%); dextrose equivalent (DE) values of maltodextrin (DE 10, 18)) on emulsion and powder properties. Results showed that all homogenised emulsions were suitable for spray-drying due to their high emulsion stability, monomodal droplet size distributions (150–180 nm) and low viscosity (20–65 mPa s). All instantised powders exhibited good dispersibility (65–90%) in water. The instantised powder with low GMO levels showed high encapsulation efficiencies (93–94%) with low surface oils (3%) and uniform droplet size distributions when reconstituted. Results demonstrated that spray-drying can successfully produce instantised powders for food applications to improve product quality.

The spray drying process of a mixed juice of acerola and seriguela was optimized using a 2 4 full factorial design with 16 factorial points and 3 central points. The independent variables were different levels of inlet temperature (110°, 140° and 170 °C), feed flow (0.36, 0.60 and 0.84 L/h), amount of maltodextrin (14-26%) and maltodextrin dextrose equivalent (DE) (5, 10 and 15 DE). The responses were water activity (Aw), moisture content (MC), hygroscopicity (Hyg), powder recovery (PR) and retention of ascorbic acid (RAA). After optimization, an acceptance test and multiple comparison test were performed. Temperature exerted a great influence on Aw, MC and RAA. The optimal drying conditions to obtain acerola and seriguela juice mix powder were an inlet temperature of 140 °C, a flow rate of 0.60 L/h, 20% maltodextrin 10 DE. There was no significant difference in the acceptance of the quality attributes or in the multiple comparison test between the nectars made with the juice mix powder. Acceptance was approximately 70%. Therefore, this acerola and seriguela mix powder can be considered a good source of ascorbic acid and a potential ingredient for the food industry.

Dielectric properties study is important in understanding the interaction between materials within electromagnetic field. By knowing and understanding the dielectric properties of materials, an efficient and effective microwave heating process and products can be designed. In this study, the dielectric properties of several encapsulation wall materials were measured using open-ended coaxial probe method. This method was selected due to its simplicity and high accuracy. All materials exhibited similar behavior. The result inferred that β-cyclodextrin (BC), starch (S), Arabic (GA) and maltodextrin (M) with various dextrose equivalent exhibited effective encapsulation wall materials in microwave encapsulation-drying technique owing to loss tangent values which were higher than 0.1 at general application frequency of 2.45 GHz. Thus, these were found to be suitable as wall material to encapsulate the selected core material in this microwave encapsulation-drying method. On contrary, sodium caseinate showed an ineffective wall material to be used in microwave encapsulation-drying. The differences in the values of dielectric constant, loss factor and loss tangent were found to be contributed by frequency, composition and bulk density. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s13197-018-3327-3) contains supplementary material, which is available to authorized users.

Confectionery gels (CGs) form a portion of the lucrative confectionery market, however there are continual consumer demands for more interesting and innovative products that have new and exciting textures, flavors and appearances. Improving or modifying CG textures can meet these demands, but first an understanding of how the behaviour and structure of the gel is developed must be achieved. Companies that will gain a competitive advantage in the confectionery market will be those able to actively manipulate and control sensory properties to meet exacting customer demands.Due to the unfavourable characteristics of current CG forming processes, including high labour and operating costs, it is necessary to explore alternative processing methods that can overcome some of the undesirable aspects of traditional processes. Extrusion processing has been used successfully for many years in the production of food products such as pasta and cereals, and may be used to form CG products. The advantage of traditional processing methods is that they produce products that have consumer-acceptable characteristics, although how these characteristics are developed has not been fully understood.The main objective of this thesis was to achieve a fundamental understanding of the microstructure and physical properties (e.g. texture, rheology) of CGs in relation to the processing method employed. This understanding could then be utilised for developing a method for predicting the characteristics of the CGs through quantitative, measurable microstructure and rheological parameters. This allows measurable product criteria and control measures to be applied to the development of a continuous process for forming these CGs.The CGs that were studied were an Australian CG product containing acid modified wheat starch, sucrose, 42 dextrose equivalent (DE) glucose syrup, gelatin, water, citric acid, flavouring and colourings. CGs were formed using different processing techniques including lab-scale and pilot plant processing methods and studies were carried out into investigating changes in the material as a result of discrete process steps which included a high temperature cooking step to gelatinise the starch, followed by a mixing step to incorporate gelatin into a cooked starch/sucrose/glucose syrup mixture. The starch and gelatin form the gel network structure in the products, forming cross-links as a result of the processing method.Characterisation of structural, textural and rheological properties of commercial CGs allowed development of proposed structure-property relationships for these CGs, as well as some preliminary determination of how current gel compositions and processing methods affect their characteristic properties. The study also allowed the setting of benchmarks for CG characteristic properties. The CGs showed a wide range of phase-separated (starch/sugar-rich and gelatin-rich regions) microstructures between different brands of products, which were attributed to several processing attributes including differences in formulation, relative viscosity of the gelling components, gelation rate, phase separation rate, order of gel formation and gel mixing kinetics. It was found that structure, rheological behaviour and textural properties were interrelated and dependent on CG age and processing history. CG composition also had a strong effect on characteristic properties, particularly the concentration levels of starch and gelatin. Textural parameters and rheological characteristics were found to show particular dependence on proportion of gelatin-rich area and major axis length of inclusions in the microstructure.Investigation of CG formation process changes during cooking, particularly rheological changes in the mixture consisting of acid-modified starch, sucrose, glucose syrup and water (SSG system) allowed better understanding of the first step in the CG gel formation process. The SSG system showed shear-thinning behaviour upon experiencing an increase in shear rate, which would cause a subsequent reduction in gel strength. The SSG system also showed that an increase in moisture content increased the rise in viscosity of the system that was achieved through high temperature processing. The system experienced a transition from Casson equation behaviour to power law fluid behaviour upon heating, indicating that a network structure had been initiated, or that a loss of yield strength had occurred. The temperatures at which significant changes in viscosity behaviour begin to occur in the SSG system were between 70-90°C, and further changes occurred at 110-130°C due to the phenomenon of starch gelatinisation taking place.Studies of the effect of mixing speed used to mix gelatin solution and cooked SSG mixture showed that increased mixing speeds caused a reduction in the size of gelatin-rich inclusions due to break-up of the gelatin-rich material. At intermediate mixing speeds there appeared to be more variation in inclusion sizes which may be due to the mixing speed being at a rate similar to the aggregation mechanism of the gelatin-rich phases. Gels with finer inclusion sizes that were a result of increased mixing speed showed reduced values of Hardness and Chewiness. This is of great importance as a measurable modification of textural parameters as changes in mixing shear rate creates the ability to modify processing technique to provide desirable gel characteristics.Finally a study was conducted to investigate the feasibility and behaviour of a confectionery gel extrusion process by studying the effect of four processing parameters: powder feed rate, feed moisture, processing temperature and screw speed. Previous studies in literature had found these extrusion parameters to be some of the most effective at manipulating product properties without having to change extruder type or screw configuration.It was found that at a processing temperature of 170°C and feed moisture of 26% powder feed rate changes in the range of 23.5-32.1 g/min affected operating characteristics such as mass flow rate and Specific Mechanical Energy (SME), but had no significant effect on gel product characteristics. Synergistic changes in feed moisture, processing temperature and screw speed did affect some gel characteristics and this was shown through Response Surface Methods (RSM). Many gel property-processing relationships could be adequately modelled with a Response Surface Model which included: Operating characteristics - Mass flow rate (g/min), Melt temperature (°C) and SME (J/g); Structural characteristics - Proportion of gelatin-rich area (%) and Fractal dimension; Moisture content and Textural parameter Chewiness; Rheological model parameter viscous modulus (E”) b in the model E" = aωb, which is a measure of cross- linking when applying classical gel-like behaviour.Operating characteristics were affected by all three processing parameters, with melt temperature being increased by increasing feed moisture and temperature, mass flow rate achieving a maxima at intermediate levels of feed moisture and temperature (22% moisture and 150°C) and SME being affected by all three process parameters. Structural, textural and rheological properties were also significantly affected by all three processing parameters. Gel moisture content increased with feed moisture content, ranging from 14-21% over a feed moisture range of 18- 26%. The gels formed through extrusion showed homogeneous microstructures and structural parameters were mainly affected by feed moisture and screw speed with proportion of gelatin- rich area affected by both of these parameters and fractal dimension significantly affected by screw speed alone, while Chewiness was significantly affected by all three processing parameters. Viscous modulus (E”) b was significantly affected by feed moisture, indicating that this processing parameter had the greatest effect on gel cross-link (network) formation.Gels extruded with the same feed moisture content and similar processing temperature as commercial gels of identical composition showed similar Hardness values (3-4 N) but displayed differences in other characteristics. Extruded gels were more homogeneous and did not show phase separation as overtly as commercial gels. Extruded gels also had higher Chewiness values and lower rheological parameter values. The extruded gels did show higher E” b values, indicating a higher sensitivity of E” with frequency. This implies that the extruded gels deviate more from classical gel-like behaviour and may contain less cross-links than the commercial gels. The twin screw shear behaviour is the main difference from current commercial production techniques and the synergistic processing behaviour of the mechanical deformation with feed moisture and processing temperature is what causes the differences in product behaviour.This research has worked to increase knowledge in the area of confectionery gel characteristics and development of such characteristics in order to develop quantifiable property-processing models for continuous extrusion production of confectionery gels. This will allow future development of a viable control model to increase the move towards a fully controllable continuous process for confectionery gel formation. Priorities for future research include further investigation into the behaviour of the confectionery gel system as well as further development of a control model for continuous extrusion processing of confectionery gels.

By using the ramping method for humidity at a constant temperature, the release rates of d-limonene were investigated from spray-dried powders with various wall materials, such as maltodextrin (MD) (dextrose equivalent (DE) = 25 and 19), lactose (Lac), and sucrose (Suc). Spray-dried powders, which were sieved to the average powder size of 107–140 µm, contained d-limonene at about 90–97 mg/g-dry powder. d-limonene release profile was measured using a dynamic vapor sorption (DVS) system coupled gas chromatography at 30, 40, and 50 °C from 10% to 90% relative humidity (RH). The linear correlation was found between the release start humidity, sRH, of d-limonene release from the powder and the glass transition temperature of wall materials. The release rates for Suc and Lac increased rapidly at certain humidities and became the maximum rates. Then, these rates decreased gradually with increasing RH. This might have been due to the powder aggregation for Suc and to crystallization for Lac. The release behaviors significantly depended on the wall materials.

The jucara fruits (Euterpe edulis Martius), native to the Atlantic Forest, are rich in anthocyanins. To preserve the anthocyanins in jucara fruit pulp, this study aimed to evaluate the effectiveness of microencapsulation by spray drying and freeze drying with maltodextrin (dextrose equivalent 16.5 to 19.5) and gum arabic in different proportions. The obtained microparticles were characterized by quantifying the total polyphenol and anthocyanin contents, by performing differential scanning calorimetry, thermogravimetry, and infrared spectroscopy and by using scanning electron microscopy to analyze the morphology of the particles. The total amount of polyphenols in the fruit pulp was 750 ± 16.7 mg GAE/100 g of the freeze-dried sample. The total anthocyanins in the fruit pulp was 181.25 ± 5.36 (mg/100 g). The microparticles were formed by employing maltodextrin and gum arabic in a 1:1 proportion as the polymeric matrix; the mixtures of pulp and polymeric matrix were prepared in proportions of 2:3 and 2:1, preserving up to 83.69% of the anthocyanin content. Lyophilization of the 2:1 mixture resulted in an anthocyanin content of 116.89 ± 4.43 (mg/100 g), whereas lyophilization of the 2:3 mixture resulted in 151.68 ± 1.39 (mg/100 g) anthocyanin content, which did not differ from the value obtained by spray drying the 2:3 mixture (150.76 ± 5.79 (mg/100 g)). Thermal analyses showed that the microparticles obtained by freeze drying at a ratio of 2:3 presented greater resistance to degradation with increasing temperature. The incorporation of the pulp in the polymeric matrix was demonstrated by IR analyses. Microparticles obtained by freeze drying showed the formation of various-sized flakes, whereas those obtained by spray drying were spherical in shape. Microencapsulation is a possible alternative for improving the stability of the anthocyanins in this fruit.

The biodegradability and the influence of the degree of substitution of cationic groups or cross-linking level of starch were studied by using enzymatic hydrolysis and two aerobic degradation methods. Cationic starches with a degree of substitution varying from 0 to 0.54 were obtained by modifying native potato starch with 2,3-epoxypropyltrimethylammonium chloride, while cross-linked starches with a degree of cross-linking varying from 0 to 92.5% were obtained by reaction of native potato starch with epichlorohydrin. Enzymatic hydrolysis experiment was performed using α-amylase preparation, and aerobic degradation studies were carried out in liquid and solid media by using ISO 14855-2 and 14851 standards methods. The dextrose equivalent, molecular weight, viscosity and biodegradability parameters were used to assess biodegradation process. Biodegradability of modified starches decreased with increasing degree of modification. The addition of cationic groups to starch to the extent >0.1 mol/molAGU reduced the biodegradability of starch derivatives, and CS became non-biodegradable when DS ≥ 0.54. The cross-linking of starch by building the alkyl chain cross-links between the polysaccharide macromolecules reduced ultimate biodegradability of starch derivatives, when the degree of cross-linking was higher than 92.5%.

Sago pith and sago hampas mainly consist of starch and fiber. In this research, acid modification of starch and fiber was conducted by high-temperature (autoclaving) and microwave-assisted treatments and slow or mild acid hydrolysis. Autoclaving and microwave-assisted treatments influenced the gelatinization and solubilization of starch granules to produce depolymerized starch and changed the fiber structure to become more amorphous forms. Heating in dilute acid produced high soluble total sugars with high dextrose equivalent, but the process also released hydroxymethylfurfural as undesired by-products. Slow or mild acid hydrolysis attacked the amorphous regions of starch and fiber. It did not change the starch and fiber crystallinity pattern but increased the degree of crystallinity. Acid modification techniques for sago starch and its fiber can be used for producing certain products such as starch sugar, fermentable sugars, and filler for biofoam production.

A process for maltodextrin production from avocado seed starch was reported in this study. Response surface methodology was used to investigate the effects of three independent variables for hydrolysis of the starch using a commercial food-grade α-amylase, Termamyl SC. These variables included enzyme concentration (0.05 – 0.15% starch), pH (5.0 – 6.0) and hydrolysis time (1.0 – 3.0 h), while the temperature fixed at 95°C. The result showed that the optimum conditions were using enzyme concentration at 0.12%, pH at 5.5 and 2.75 h of the incubation time. Under the optimum conditions, the recovered starch yield was 79.8% and the maltodextrin powder had 15.8 of dextrose equivalent.

Alpha-amylase is an enzyme in the conversion of starch to maltodextrin. The study investigated the effect of pH and temperature on the activities of alpha-amylase in the conversion of starch to maltodextrin. The optimum condition of cassava starch hydrolysis was determined by using a pure culture of a thermostable alpha-amylase for liquefaction, and the activity of the enzyme determined at varying pH, temperature and time. A 3 x 3 x 3 completely randomized experimental design comprising 3 pH values (pH 6.0, 6.5 and 7.0); 3 temperatures (65, 70 and 75°C) and 3 time ranges (40, 50 and 60 min) were employed for liquefaction. Results showed that sample dry weight decreased with increasing value of pH, temperature and time. The optimal reducing sugar and dextrose equivalent were 17.84% and 14.74 DE, respectively at pH 6.5, 70°C and 60 min. The maltodextrin obtained may serve as a substrate in glucose syrup production

The preparation of Cross-Linked Enzyme Aggregates (CLEAs) is a simple and cost-effective technique capable of generating insoluble biocatalysts with high volumetric activity and improved stability. The standard CLEA preparation consists of the aggregation of the enzyme and its further crosslinking, usually with glutaraldehyde. However, some enzymes have too low a content of surface lysine groups to permit effective crosslinking with glutaraldehyde, requiring co-aggregation with feeders rich in amino groups to aid the formation of CLEAs. The co-aggregation with magnetic particles makes their handling easier. In this work, CLEAs of a commercial amyloglucosidase (AMG) produced by Aspergillus niger were prepared by co-aggregation in the presence of polyethyleneimine (PEI) or starch with aminated magnetic nanoparticles (MNPs) or bovine serum albumin (BSA). First, CLEAs were prepared only with MNPs at different glutaraldehyde concentrations, yielding a recovered activity of around 20%. The addition of starch during the precipitation and crosslinking steps nearly doubled the recovered activity. Similar recovered activity (around 40%) was achieved when changing starch by PEI. Moreover, under the same conditions, AMG co-aggregated with BSA was also synthesized, yielding CLEAs with very similar recovered activity. Both CLEAs (co-aggregated with MNPs or BSA) were four times more stable than the soluble enzyme. These CLEAs were evaluated in the hydrolysis of starch at typical industrial conditions, achieving more than 95% starch-to-glucose conversion, measured as Dextrose Equivalent (DE). Moreover, both CLEAS could be reused for five cycles, maintaining a DE of around 90%. Although both CLEAs had good properties, magnetic CLEAs could be more attractive for industrial purposes because of their easy separation by an external magnetic field, avoiding the formation of clusters during the filtration or centrifugation recovery methods usually used., This research was funded in part by the Conselho Nacional de Desenvolvimento Científico e Tecnológico, grant #142107/2015-8, Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Finance Code 001, and Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP), grant #2016/10636-8. We gratefully recognize financial support from Project CTQ2017-86170-R (MINECO, Spain).

Maltodextrin (MX) is an ingredient in high demand in the food industry, mainly for its useful physical properties which depend on the dextrose equivalent (DE). The DE has however been shown to be an inaccurate parameter for predicting the performance of the MXs in technological applications, hence commercial MXs were characterized by mass spectrometry (MS) to determine their molecular weight distribution (MWD) and degree of polymerization (DP). Samples were subjected to different water activities (aw). Water adsorption was similar at low aw, but radically increased with the DP at higher aw. The decomposition temperature (Td) showed some variations attributed to the thermal hydrolysis induced by the large amount of adsorbed water and the supplied heat. The glass transition temperature (Tg) linearly decreased with both, aw and DP. The microstructural analysis by X-ray diffraction showed that MXs did not crystallize with the adsorption of water, preserving their amorphous structure. The optical micrographs showed radical changes in the overall appearance of the MXs, indicating a transition from a glassy to a rubbery state. Based on these characterizations, different technological applications for the MXs were suggested.