Some properties of corn starches II: Physicochemical,gelatinization, retrogradation,pasting and gel textural properties

The physicochemical, thermal, pasting and gel textural properties of corn starches from different corn varieties (African Tall, Ageti, Early Composite, Girja, Navjot, Parbhat, Partap, Pb Sathi and Vijay) were studied. Amylose content and swelling power of corn starches ranged from 16.9% to 21.3% and 13.7 to 20.7 g/g, respectively. The enthalpy of gelatinization (ΔH_gel) and percentage of retrogradation (%R) for various corn starches ranged from 11.2 to 12.7 J/g and 37.6% to 56.5%, respectively. The range for peak viscosity among different varieties was between 804 and 1252 cP. The hardness of starch gels ranged from 21.5 to 32.3 g. African Tall and Early Composite showed higher swelling power, peak, trough, breakdown, final and setback viscosity, and lower ΔH_gel and range of gelatinization. Pearson correlations among various properties of starches were observed. Gelatinization onset temperature (T_o) was negatively correlated to peak-, breakdown-, final- and setback viscosity (r = −0.809, −0.774, −0.721 and −0.686, respectively, p < 0.01) and positively correlated to pasting temperature (r = 0.657, p < 0.01). ΔH_gel was observed to be positively correlated with T_o, peak gelatinization temperature and (T_p) and gelatinization conclusion temperature T_c (r = 0.900, 0.902 and 0.828, respectively, p < 0.01) whereas, it was negatively correlated to peak- and breakdown- (r = −0.743 and −0.733, respectively, p < 0.01), final- and setback viscosity (r = −0.623 and −0.611, respectively, p < 0.05). Amylose was positively correlated to hardness (r = 0.511, p < 0.05) and gumminess (r = 0.792, p < 0.01) of starch gels.     

Physicochemical properties,anti-nutritional and bioactive constituents,in vitro digestibility,and techno-functional properties of bioprocessed whole wheat flour

This study investigated the impact of bioprocessing techniques (germination, solid-state fermentation, the combination of germination, and solid-state fermentation) on the physicochemical properties, anti-nutritional and bioactive constituents, in vitro digestibility, and techno-functional properties of whole wheat grains were investigated. Bioprocessed whole wheat flour (WWF) samples and the raw flour (control) were prepared using standard procedures. Proximate, anti-nutritional, mineral and amino acid (AA) compositions, protein digestibility, antioxidant activities, starch characteristics, and techno-functional properties were studied using standard methods. The bioprocessing methods increased (p ≤ 0.05) the protein (13.37–16.84 g/100 g), total dietary fiber, mineral constituents, resistant starch (7.19–9.87 g/100 g), slowly digestible starch, phenolic content, antioxidant activities (ferric reducing antioxidant power (FRAP) and 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity), most AAs, and protein digestibility. Also observed were decreases (p ≤ 0.05) in rapidly digestible starch, phytic acid, tannin, and trypsin inhibitor activity. The adopted bioprocessing techniques modified the thermal, functional, color, and pasting properties of the WWF and resulted in molecular interactions in some functional groups, as revealed by Fourier transform infrared spectroscopy, compared to the raw flour. The combination of germination and fermentation improved the physicochemical (titratable acidity = 4.93%), protein (16.84/100 g) and starch digestibility (resistant starch = 9.87%), antioxidant (FRAP = 78.90 mg/GAE/100 g), and mineral contents (calcium = 195.28 mg/100 g), modified the pasting (peak viscosity = 90.34 RVU), thermal (peak temperature = 64.82°C), and color properties of WWF with reduced anti-nutritional factors. The combination of these processing techniques could serve as a natural and low-cost technique for the modification of whole wheat functionality and subsequently as an improved functional ingredient during food product development.     

Banana cultivars, cultivation practices, and physicochemical properties

The physicochemical (pH, texture, Vitamin C, ash, fat, minerals) and sensory properties of banana were correlated with the genotype and growing conditions. Minerals in particular were shown to discriminate banana cultivars of different geographical origin quite accurately. Another issue relates to the beneficial properties of bananas both in terms of the high dietary fiber and antioxidant compounds, the latter being abundant in the peel. Therefore, banana can be further exploited for extracting several important components such as starch, and antioxidant compounds which can find industrial and pharmaceutical applications. Finally, the various storage methodologies were presented with an emphasis on Modified Atmosphere Packaging which appears to be one of the most promising of technologies.     

Buckwheat starch: Structures,properties, and applications

BackgroundThere is increasing interest in utilization of buckwheat for healthy food applications. Common buckwheat (Fagopyrum esculentum) and tartary buckwheat (Fagopyrum tataricum) are cultivated in Asia, Europe, and Americas for various food formulation and production. Starch, the major component of the seeds, may account over 70% of the dry weight. Therefore, it is expected that, to a large extent, the quality of starch determines the quality of buckwheat food products. Furthermore, Buckwheat starch has great potential for various food and non-food uses due to the unique structural and functional features.Scope and approachThis review summarises the current knowledge of chemical composition, chemical structure of amylose and amylopectin, physical structure of granules, physicochemical properties, enzyme susceptibility, modifications, and uses of buckwheat starch. Suggestions on how to better understand and utilise the starch are provided.Key findings and conclusionsAmylose contents of buckwheat starch ranged from 20 to 28%. Starch granules are most polygonal with size ranging from ∼2 to 15 μm and an average diameter of ∼6–7 μm. The polymorph is A-type. The amount of extra-long unit chains of amylopectin (DP > 100) is higher than that of cereal amylopectins. Low glycaemic index of buckwheat food products could be attributed to the non-starch components. Buckwheat starch has been used as fat replacer, ingredient for extruded products, nanocomposite material, and fermentation substrate for alcoholic beverage. It may be concluded that buckwheat starch can be a unique source of specialty starch for innovative food and non-food applications.     

Fat properties during homogenization, spray-drying, and storage affect the physical properties of dairy powders

Changes in fat properties were studied before, during, and after the drying process (including during storage) to determine the consequences on powder physical properties. Several methods were combined to characterize changes in fat structure and thermal properties as well as the physical properties of powders. Emulsion droplet size and droplet aggregation depended on the homogenizing pressures and were also affected by spray atomization. Aggregation was usually greater after spray atomization, resulting in greater viscosities. These processes did not have the same consequences on the stability of fat in the powders. The quantification of free fat is a pertinent indicator of fat instability in the powders. Confocal laser scanning microscopy permitted the characterization of the structure of fat in situ in the powders. Powders from unhomogenized emulsions showed greater free fat content. Surface fat was always overrepresented, regardless of the composition and process parameters. Differential scanning calorimetry melting experiments showed that fat was partially crystallized in situ in the powders stored at 20°C, and that it was unstable on a molecular scale. Thermal profiles were also related to the supramolecular structure of fat in the powder particle matrix. Powder physical properties depended on both composition and process conditions. The free fat content seemed to have a greater influence than surface fat on powder physical properties, except for wettability. This study clearly showed that an understanding of fat behavior is essential for controlling and improving the physical properties of fat-filled dairy powders and their overall quality.     

Allitol: production,properties and applications

Allitol is a rare alcohol monosaccharide sweetener containing six carbons atoms. It is a major product of the d ‐psicose reduction pathway that exerts various physiological effects, for example laxative effects for the treatment of constipation and anti‐obesity effects by suppressing lipid accumulation. Allitol can be also used as an anticrystallisation agent. In addition, allitol cross‐links d ‐ and l ‐hexoses, thus contributing to production of l ‐psicose. This is a review of the recent studies on the sources, properties, physiological functions and applications of allitol. In addition, the biochemical properties of ribitol dehydrogenase enzymes and the biotechnological production of allitol via microbial and enzymatic synthesis from d ‐psicose and directly from d ‐fructose are reviewed.     

Saponins: properties, applications and processing

Saponins are a diverse group of compounds widely distributed in the plant kingdom, which are characterized by their structure containing a triterpene or steroid aglycone and one or more sugar chains. Consumer demand for natural products coupled with their physicochemical (surfactant) properties and mounting evidence on their biological activity (such as anticancer and anticholesterol activity) has led to the emergence of saponins as commercially significant compounds with expanding applications in food, cosmetics, and pharmaceutical sectors. The realization of their full commercial potential requires development of new processes/processing strategies to address the processing challenges posed by their complex nature. This review provides an update on the sources, properties, and applications of saponins with special focus on their extraction and purification. Also reviewed is the recent literature on the effect of processing on saponin structure/properties and the extraction and purification of sapogenins.     

Geotextiles: production,properties and performance

The monograph critically reviews most commonly used geotextile structures, their properties and performance characteristics. In general, both natural and synthetic fibres are used for the production of geotextiles, and the advantages and disadvantages of each type of fibre are discussed for various applications of geotextiles. The important functions of geotextiles, i.e. filtration, drainage, separation and reinforcement have been identified and have been related to several properties and major applications of geotextiles. Various geotextile properties, namely mechanical, hydraulic and chemical and their test methods have been critically discussed. A process–structure–property relationship for most commonly used geotextiles is also analysed. Furthermore, the design of a geotextile is of paramount importance for any civil engineering application. Thus, the design criteria for various functions of geotextiles have been addressed. Subsequently, the durability characteristics of geotextile have been introduced for analysing the performance over its lifetime.     

Starch-based noodles: Current technologies,properties, and challenges

Starch noodles are gaining interest due to the massive popularity of gluten-free foods. Modified starch is generally used for noodle production due to the functional limitations of native starches. Raw materials, methods, key processing steps, additives, cooking, and textural properties determine the quality of starch noodles. The introduction of traditional, novel, and natural chemical additives used in starch noodles and their potential effects also impacts noodle quality. This review summarizes the current knowledge of the native and modified starch as raw materials and key processing steps for the production of starch noodles. Further, this article aimed to comprehensively collate some of the vital information published on the thermal, pasting, cooking, and textural properties of starch noodles. Technological, nutritional, and sensory challenges during the development of starch noodles are well discussed. Due to the increasing demands of consumers for safe food items with a long shelf life, the development of starch noodles and other convenience food products has increased. Also, the incorporation of modified starches overcomes the shortcomings of native starches, such as lack of viscosity and thickening power, retrogradation characteristics, or hydrophobicity. Starch can improve the stability of the dough structure but reduces the strength and resistance to deformation of the dough. Some technological, sensory, and nutritional challenges also impact the production process.     

低聚异麦芽糖性质、功能、生产和应用

低聚异麦芽糖是一种集营养、保健、疗效于一体功能性低聚糖,在食品、医药、饲料等行业有着广泛应用;该文对低聚异麦芽糖性质、功能、生产及应用进行综述。     

醋的性能、源流、工艺和品质

0食药皆宜话食醋食醋 是世界上最古老、最普及的调味副食品，几乎每个国家和地区都生产食醋。人们喜爱食醋历数千年而不衰，是因为食醋有较高的营养性能和享受性能。     

Structure,physicochemical properties,and uses of millet starch

There has been increased interest in millet utilization due to the various “rediscovered” health benefits and also critical role in food security in semiarid areas of Africa and Asia. The major component of millets is starch, which may amount up to 70% of the seed and determines the quality of millet products. This review summarizes the current knowledge of the isolation, chemical composition, structure, physicochemical properties, enzyme susceptibility, modifications, and uses of millet starch. Lack of systematic knowledge of millet starch seriously hinders further development of millets as sustainable crops. Needed research to diversify the variations in the quality and to improve the utilization of this starch is suggested.     

Structures,physicochemical properties,and applications of amaranth starch

Amaranth as a rediscovered “new” crop is becoming a research focus in the recent two decades. The major carbohydrate of some amaranth species is starch, which accounts up to around 60% of the dry grains. This review summarizes the present knowledge of the isolation, composition, structures, physiochemical properties, modifications, and applications of amaranth starches, and provides suggestions for research to further improve the utilization.     

Biochemical properties,nutritional quality,colour profile and techno-functional properties of whole grain sourdough and malted cowpea and quinoa flours

The particular interest in biomodifications of underutilised but nutritionally distinct whole grains is vital to promote diet diversity, nutrition transition and food security. This study investigated the use of short-term solid-state fermentation and germination to ease processability and improve the quality characteristics of whole grain (WG) cowpea and quinoa flours. The fermented and germinated WG flours were prepared at 28 °C for 48 h. The biochemical, nutritional quality and techno-functional properties of the obtained flours were determined. The macromolecules’ biomodification by microbial metabolism and endogenous enzymes activation influenced quality variations in the biomodified flours. The cowpea sourdough flour (CSF) presented lower acidity (pH 4.72), higher total flavonoid (29.63 mg QE/g), total phenolic (8.21 mg GAE/g) and antioxidant activity. The flour also showed high contents of fibre (5.30%), ash (4.42%), calcium (864.49 mg/kg), potassium (12848.64 mg/kg), zinc (33.83 mg/kg), good protein (21.43%) and a moderate fat level (2.65%). Higher oil absorption and water solubility indices were also noted for CSF. In contrast, malted quinoa flour (MQF) exhibited higher swelling power, increased dispersibility and improved final, peak and trough viscosities. The CSF displayed higher redness and browning index, whereas MQF had greater lightness. The results suggest that CSF and MQF had the best complementary quality attributes. Their formulation as gluten-free, whole and multigrain ingredients may promote healthy choices for individualised growing dietary needs.     

微孔淀粉的制备性质及应用

微孔淀粉是用具有生淀粉酶活力的酶在低于淀粉糊化温度下水解生淀粉形成的一种新型变性淀粉。微孔淀粉经交联、表面活性处理后，能改善其机械性能和表面性质。目前微孔淀粉主要用作微胶囊芯材、吸附剂和脂肪替代物等。     

壳聚糖的性质、生产及应用

壳聚糖可应用于水处理、医疗卫生、食品及保健食品等领域,通常从虾、蟹壳中提取,但由于原料的不稳定性使壳聚糖的产量和质量受到影响。因此,从20世纪80年代后期,日本和美国先后开始研究用微生物发酵的方法生产壳聚糖。现对壳聚糖的性质、应用以及生产方法作一综述。     

真菌漆酶的生产、性质和应用

本文总结了真菌漆酶的发酵法生产与活力测定方法，介绍了漆酶的结构和活性部位，重点介绍了漆酶的理化性质和乍物学功能，还详述了真菌漆酶在有机合成、环保、食品和造纸等行业中的应用。