Chapter 1: Introduction
Chapter 2: Theory of the Analytical Procedure
Chapter 3: Kit Content & Reagent Preparation
Chapter 4: Weighing of Samples
Chapter 5: Starch Pretreatment
Chapter 6: Precipitation of Amylopectin with Con A & the Determination of Amylose
Chapter 7: Determination of Total Starch
Chapter 8: Determination of D-Glucose in Amylose and Total Starch Fractions
Chapter 9: Calculation of Amylose Content
100 assays per kit
Prices exclude VAT
Available for shipping
|Content:||100 assays per kit|
Short term stability: 2-8oC,
Long term stability: See individual component labels
|Stability:||> 2 years under recommended storage conditions|
|Limit of Detection:||Amylose 5-95% of total starch content|
|Total Assay Time:||~ 120 min|
|Application examples:||Cereal starches, flours, pure starches and foods.|
|Method recognition:||Novel method|
The Amylose/Amylopectin test kit is suitable for the measurement and analysis of amylose/amylopectin ratio and content in cereal starches and flours. Based on a Con A precipitation procedure.
See our full list of polysaccharide test kits.
- Very cost effective (cost per test)
- All reagents stable for > 12 months after preparation
- Only enzymatic kit available
- Accurate and reliable amylose / amylopectin ratio determination
- Simple format
- Standard included
McCleary, B. V., Charnock, S. J., Rossiter, P. C., O’Shea, M. F., Power, A. M. & Lloyd, R. M. (2006). Journal of the Science of Food and Agriculture, 86(11), 1648-1661.
Procedures for the measurement of starch, starch damage (gelatinised starch), resistant starch and the amylose/amylopectin content of starch, β-glucan, fructan, glucomannan and galactosyl-sucrose oligosaccharides (raffinose, stachyose and verbascose) in plant material, animal feeds and foods are described. Most of these methods have been successfully subjected to interlaboratory evaluation. All methods are based on the use of enzymes either purified by conventional chromatography or produced using molecular biology techniques. Such methods allow specific, accurate and reliable quantification of a particular component. Problems in calculating the actual weight of galactosyl-sucrose oligosaccharides in test samples are discussed in detail.Hide Abstract
McCleary, B. V., Gibson, T. S. & Mugford, D. C. (1997). Journal of AOAC International, 80, 571-579.
An American Association of Cereal Chemists/AOAC collaborative study was conducted to evaluate the accuracy and reliability of an enzyme assay kit procedure for measurement of total starch in a range of cereal grains and products. The flour sample is incubated at 95 degrees C with thermostable alpha-amylase to catalyze the hydrolysis of starch to maltodextrins, the pH of the slurry is adjusted, and the slurry is treated with a highly purified amyloglucosidase to quantitatively hydrolyze the dextrins to glucose. Glucose is measured with glucose oxidase-peroxidase reagent. Thirty-two collaborators were sent 16 homogeneous test samples as 8 blind duplicates. These samples included chicken feed pellets, white bread, green peas, high-amylose maize starch, white wheat flour, wheat starch, oat bran, and spaghetti. All samples were analyzed by the standard procedure as detailed above; 4 samples (high-amylose maize starch and wheat starch) were also analyzed by a method that requires the samples to be cooked first in dimethyl sulfoxide (DMSO). Relative standard deviations for repeatability (RSD(r)) ranged from 2.1 to 3.9%, and relative standard deviations for reproducibility (RSD(R)) ranged from 2.9 to 5.7%. The RSD(R) value for high amylose maize starch analyzed by the standard (non-DMSO) procedure was 5.7%; the value was reduced to 2.9% when the DMSO procedure was used, and the determined starch values increased from 86.9 to 97.2%.Hide Abstract
Gibson, T. S., Solah, V. A. & McCleary, B. V. (1997). Journal of Cereal Science, 25(2), 111-119.
A modified procedure for the determination of amylose in cereal starches and flours based on complex formation between the lectin concanavalin A (Con A) and amylopectin has been developed and characterised. The assay format is suitable for multi-sample analysis, allowing the analysis of up to 20 samples per day. In the procedure, the amylopectin in a solubilised, lipid-free starch sample is precipitated by reaction with Con A and removed by centrifugation. The amylose remaining in the supernatant is then determined after amylolytic hydrolysis to glucose and expressed as a proportion (%) of the glucose derived from amylolytic hydrolysis of the total starch in a separate aliquot of the solubilised sample (i.e. prior to Con A treatment). The Con A procedure correlates well (r>0•993) with existing Con A-based and iodine-based procedures and yields a linear standard curve for starch samples containing from ∼0 to ∼100% amylose. Advantages of this modified Con A procedure for amylose determination include its applicability to flour samples without the need for prior starch purification; it allows the simultaneous estimation of total starch and does not require a calibration curve. Repeated analyses of a set of samples yielded repeatability (within laboratory) relative standard deviations of <5% for pure starches and ∼10% for flours. A commercially available assay kit has been developed to facilitate the use of the Con A procedure in routine amylose determinations.Hide Abstract
Storage of biofortified maize in Purdue Improved Crop Storage (PICS) bags reduces disulfide linkage-driven decrease in porridge viscosity.
Nkhata, S. G., Liceaga, A. M., Rocheford, T., Hamaker, B. R. & Ferruzzi, M. G. (2021). LWT, 136, 110262.
Assessing rheological properties of biofortified maize through post-harvest storage is critical for its successful translation to consumer foods. Changes in flour rheology were assessed following post-harvest storage in Purdue Improved Crop Storage (PICS) of a white and two biofortified orange maize genotypes (OPVI and OPVII). Whole grains were stored in PICS bags with (PICS-oxy) or without (PICS-noxy) oxygen scavenger and compared to storage in traditional polypropylene woven bags. Flour pasting profiles were assessed over 8 months of storage. Initial porridge viscosities from biofortified maize were lower than from white maize. After 8 months, higher viscosities (p < 0.05) were observed in grain stored in PICS relative to woven bags. Sequestration of oxygen had a modest but significant effect (p < 0.05) on peak and final viscosities supporting the notion that oxidative processes mediate these effects. DTT treatment partially restored porridge viscosity suggesting disulfide linkages are involved in rheological changes during storage. Raman spectral analysis suggested storage-induced structural changes to the starch matrix. Overall, storage of biofortified maize in PICS alleviated disulfide linkage-driven decreases in viscosity of cooked porridge. With the potential to improve cooking quality of biofortified maize flours, application of PICS may be useful in translation of these grains to consumers.Hide Abstract
Physicochemical, thermal and rheological properties of isolated Argentina quinoa starch.
López-Fernández, M. P., Rodríguez, S. D., Favre, L. C., Busch, V. M. & del Pilar Buera, M. (2021). LWT, 135, 110113.
The aim of the present study was to evaluate the physicochemical, thermal and pasting properties of the starch of six quinoa genotypes native to the northwest of Argentina. The genotypes belonging to two genotype groups, highlands and dry valley, were grown in Jujuy, Argentina. Significant differences among genotypes were observed (P < 0.05) in amylose content, swelling power, water-binding capacity, thermal and pasting properties. In the different genotypes, the starch was characterized by a typical A-type X-ray diffraction pattern, with relative crystallinity ranging between 26.1 and 28.5%. Granule-bound starch synthase (GBSS), which is the single enzyme responsible for amylose biosynthesis, was also identified, with the 67- and 58-kDa quinoa polypeptides corresponding to the full-length and mature GBSS proteins. Studies of the pasting properties showed that the starch of the genotypes from the highlands had lower peak viscosity and lower breakdown parameter than that of the genotypes from the dry valleys. The results showed that the genotypic background and the environment influence the pasting curves. The novel findings discussed in this study constitute a starting point for research focusing on incorporating innovative technologies in the food and biomaterials industry.Hide Abstract
Granule morphological and structural variability of Thai certified glutinous rice starches in relation to thermal, pasting, and digestible properties.
Thitisaksakul, M., Sangwongchai, W., Mungmonsin, U., Promrit, P., Krusong, K., Wanichthanarak, K. & Tananuwong, K. (2020). Cereal Chemistry, In Press.
Background and objectives: Variation in composition and functionality of glutinous rice starch greatly affects their industrial application. This study examined the starch compositional, structural, and functional variability among five Thai glutinous rice cultivars, and the effect of molecular structure and composition on starch functionality was pinpointed. Findings: Amylose content, amylopectin chain‐length distribution (CLD), and relative crystallinity were not different among the cultivars (p ≤ .05), whereas RD14 possessed largest mean granule diameter. Conclusion temperature of gelatinization and peak viscosity (PV) were lowest in RD6 and RD10, respectively, while RD6, RD10, and RD14 had lower breakdown (BD) compared to others. Despite small variation within each parameter, multivariate analysis revealed the distinct characteristic of waxy donor, RD6, and RD10 compared to others. Proportion of amylopectin B1 chains and granule size showed negative correlation (r > 0.5) with PV and BD, respectively, whereas proportion of amylopectin B2 chains positively correlated (r > 0.5) with PV and final viscosity (FV). Conclusion: Amylopectin CLD and starch granule size were the key factors determining starch pasting properties among these waxy rice genotypes. Significance and novelty: Variations in composition, structure, and properties of Thai glutinous rice starches were observed, which could be adopted for a diverse array of end uses.Hide Abstract
Soaking induced discrepancies in oenological properties, flavor profiles, microbial community and sensory characteristic of Huangjiu (Chinese rice wine).
Yang, Y., Xia, Y., Hu, W., Tao, L., Liu, H., Xie, C., Bai, W. & Ai, L. (2020). LWT, 110575.
Soaking is a crucial process in adjusting initial fermentation acidity and achieving desired flavor quality of rice wines. Effects of soaking time on physicochemical characteristic of rice, flavor profiles, microbial community and sensory characteristic of Huangjiu were investigated. Soaking caused significantly changes in amylopectin content, and rice with high amylopectin content was conducive to produce esters and aldehydes during Hungjiu brewing. High-throughput sequencing showed that bacteria types were more abundant than fungi during brewing, suggesting that bacterial community might be primarily responsible for Huangjiu flavor. Differential analysis revealed that Weissella and Enterobacter contributed greatly to the accumulation of alcohols, esters and aldehydes during Huangjiu brewing, while Clostridium, Acinetobacter, Cyanobacteria, Zymomonas and Exiguobacterium were responsible for the rancidity. Based on spearman's correlation analysis, Lactococcus, Weissella, Pediococcus, Lactobacillus and Staphylococcus were the key microbial genera responsible for the flavor characteristic of Huangjiu. While favorable soaking caused an increased intensity in alcohol-aroma, full body and continuation of resultant Huangjiu, insufficient soaking led to a higher intensity of bitter taste. Summarily, soaking acidity ranged from 2 to 3 g/L was beneficial for preventing rancidity and improving the production of flavor compounds in Huangjiu.Hide Abstract
Influence of moisture and amylose on the physicochemical properties of rice starch during heat treatment.
Yang, Z., Hao, H., Wu, Y., Liu, Y. & Ouyang, J. (2020). International Journal of Biological Macromolecules, 168, 656-662.
Moisture and amylose are important factors affecting the quality of heat-treated starches. The amylose content in heat-treated rice starch increased as moisture content (MC) increased from 8% to 30%, but decreased at MC of 70%. With the increase of MC, the paste transmittance, gelatinization temperature, and digestibility of starch increased, whereas the swelling power and enthalpy decreased. The long- and short-range molecular order and the digestive properties of starch with MC ≤ 30% changed moderately, but high MC (70%) gelatinized the starch and drastically changed the physicochemical properties. High amylose content in rice starch led to low long- and short-range molecular order, swelling power, and gelatinization temperature, but increased resistant starch. The results indicated that 30% of MC separates effects of heat treatment of starch, where low MC (≤30%) and high amylose lowers digestibility, which is beneficial for diabetics, while high MC (>30%) promotes solubility and transparency.Hide Abstract
Physicochemical, morpho-structural and rheological characterization of starches from three Phaseolus spp. landraces grown in Chiapas.
Zapata-Luna, R. L., Ayora-Talavera, T., Pacheco, N., García-Márquez, E., Espinosa-Andrews, H., Ku-González, Á., Ruiz-Ruiz, J. & Cuevas-Bernardino, J. C. (2020). Journal of Food Measurement and Characterization, 1-12.
In this study starches were isolated from Mexican bean landraces of three Phaseolus species (P. polyanthus, P. acutifolius, and P. vulgaris L.). The physicochemical, structural, morphological, and rheological properties, including yield, proximate composition, minerals, swelling power, solubility, amylose content, zeta potential, Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), Scanning electron microscopy (SEM), apparent viscosity, and viscoelastic properties were characterized. The starches of the three Phaseolus species exhibited yield, protein, and ash contents of 21.4-28.7%, 0.32-1.12%, and 0.17–0.50%, respectively. Swelling power, solubility, amylose, and zeta potential were 3.06-3.27 g/g, 0.13-0.77%, 28.51-30.99%, and - 42.03 to + 1.46 mV, respectively. The FTIR intensities showed ratios of ordered crystalline to amorphous domains from 0.702 to 0.713. All XRD results revealed that three Phaseolus species had C-type crystallinity. The majority of starch granules were oval. The rheological parameters showed that all starch gels presented shear-thinning and semi-solid viscoelastic behaviors. The native starch gels of the three Phaseolus species showed consistency indexes varying from 26.53 to 4.55 Pa sn, and gel strengths ranging from 37.15 to 109.99 Pa. The present work provides information on non-conventional bean starch properties, which should be useful tool for future studies on their applications in the food and non-food industries.Hide Abstract
Aroma, Quality, and Consumer Mindsets for Shelf-Stable Rice Thermally Processed by Reciprocal Agitation.
Dixon, W. R., Morales-Contreras, B. E., Kongchum, M., Xu, Z., Harrell, D., Moskowitz, H. R. & Wicker, L. (2020). Foods, 9(11), 1559.
Food engineering, food chemistry, and consumer segmentation were used to evaluate ready-to-eat rice. The aromatic Louisiana Clearfield Jazzman (CJ) and Thai Jasmine (TJ), and a non-aromatic parboiled (PB) rice were hydrated during the first 10 min of processing with reciprocal agitation followed by static retort processing. The aroma compound, 2-Acetyl-1-pyrroline (2-AP) was more heat-stable in CJ than TJ rice but decreased 15-fold compared to the rice cooker method. Pareto analysis indicated that rice type and agitation had the main effect on amylose and total starch and chroma and hue. Color differences of rice agitated during hydration and between rice cooker or static retort processed rice, indicated only slight differences for each rice variety. Hydration of dry rice during retort cooking and similar starch, color, and aroma quality were achieved with reciprocal compared to static or rice cooker methods. Survey responses categorized consumers into three, mindsets driven by rice consumption, convenience, or packaging.Hide Abstract
Effect of kernel type on hardness and interrelationship with endosperm chemical components of Malawian local maize (Zea mays L.) varieties during storage.
Nguma, E., Murayama, D., Munthali, C., Onishi, K., Mori, M., Tani, M., Palta, J. P., Koase, H. & Aiuchi, D. (2020). African Journal of Agricultural Research, 16(10), 1448-1456.
The aim of this study was to establish the attributes of kernel type based on kernel hardness and its interrelationship with maize endosperm chemical components, which are essential during storage. Three local varieties and one hybrid variety commonly grown by smallholder farmers in central Malawi were used. For storage experiment, the maize samples were infested with Prostephanus truncatus, larger grain borer (LGB) for eight weeks. Due to the high propensity of maize to cross-pollinate, the kernels were classified into flint and dent kernels to establish the physicochemical properties of the kernel type and variety independently. Local variety (L-3) exhibited the lowest number and weight of damaged grains and the highest adult LGB cadavers. Local variety, L-1 and L-3 had significantly the highest proportion of flint kernels type. Moreover, flint kernels of local varieties showed significantly the highest hardness, and the highest content of protein, total zein, α-zein and zinc (p < 0.05). Furthermore, hardness was significantly and positively correlated with total zein and 14 kDa β-zein content (p < 0.05). Zein in the endosperm, particularly 19 and 22 kDa α-zein mainly contributed to distinct hardness of the local varieties hence may contribute to physical barrier of the kernels against storage pests.Hide Abstract
Nutritional quality and in vitro digestion of immature rice-based processed products.
Miraji, K. F., Linnemann, A. R., Fogliano, V., Laswai, H. S. & Capuano, E. (2020). Food & Function, 11(9), 7611-7625.
Rice is commonly consumed as fully mature grain, but immature rice is considered to have better nutrient and technological properties. This is attributed to changes in content and profile of nutritional and functional compounds during maturation. This study assessed the effect of maturity on nutrient content of rice grains, and in vitro digestibility of starch and protein, for immature rice grains of TXD306 and Lawama varieties. The effect of processing of immature rice into so-called pepeta, traditionally produced from immature rice grains and widely consumed in Tanzania, was studied as well. The results showed reductions in lipid, protein, ash, thiamine, nicotinic acid, nicotinamide, and soluble and insoluble dietary fibre contents during rice grain development. However, no effect of maturity on in vitro starch and protein digestibility was observed. The contents of protein, ash, lipid, nicotinamide, iron, zinc, and total, soluble and insoluble dietary fibre were higher in pepeta from both varieties than in the corresponding rice grains. Protein digestibility of pepeta flour was 58.9% higher than that of cooked rice for variety TXD306, and 73.8% higher for Lawama. Differential scanning calorimetry indicated that starch of processed immature rice was completely gelatinized whereas its susceptibility to digestion in vitro was slightly lower than for cooked rice, possibly due to the higher cellular integrity retained after processing. These results demonstrate that pepeta-type processing improves the nutritional properties of rice and its potential use as a snack or ingredient in cereal-based formulas.Hide Abstract
Genotype-dependent and heat-induced grain chalkiness in rice correlates with the expression patterns of starch biosynthesis genes.
Gann, P. J. I., Esguerra, M. Q., Counce, P. A. & Srivastava, V. (2020). BioRxiv, In Press.
To understand the molecular basis of environment-induced and genotype-dependent chalkiness, six rice genotypes showing variable chalk levels were subjected to gene expression analysis during reproductive stages. In the high chalk genotypes, the peak expressions of ADP-Glucose Pyrophosphorylase (AGPase) Large Subunit 4 (AGPL4) occurred in the stages before grain filling commenced, creating a temporal gap with the upregulation of Granule Bound Starch Synthase I (GBSSI) and Starch Synthase IIA (SSIIA). Whereas, in the low chalk genotypes, AGPL4 expression generally occurred in later stages, close to the upregulation of GBSSI and SSIIA. However, heat treatment altered the expression pattern and created a gap between the expression peaks of AGPL4, and GBSS1 and SSIIA. This change was accompanied by transformed granular morphology, increased protein content, and chalkiness in the grains. AGPL4 expression pattern may partially explain chalkiness as it contributes to the pool of ADP-Glucose for producing amylose and amylopectin, the major components of the starch. Down-regulation of AGPase during grain filling stages could result in a limited pool of ADP-Glucose leading to inefficient grain filling and air pockets that contribute to chalkiness. The study suggests a mechanism of grain chalkiness based on the coordination of the three starch biosynthesis genes in rice.Hide Abstract
Quality matrix reveals the potential of Chak-hao as a nutritional supplement: a comparative study of matrix components, antioxidants and physicochemical attributes.
Krishnan, V., Awana, M., Rani, A. R., Bansal, N., Bollinedi, H., Srivastava, S., Sharma, S. K., Singh, A. K., Singh, A. & Praveen, S. (2020). Journal of Food Measurement and Characterization, 1-15.
In the current trend of increased health consciousness in response to increased incidence of lifestyle disorders, functional foods, and nutritional supplements got immense acceptance globally. Whole grain foods rich in functional bio-actives being a better substitute for supplements, there is an emerged interest in exploring potential candidates like pigmented rice. The present study thus aims to evaluate the natural variability in matrix composition owing nutritional and antioxidant potential of pigmented niche rice varieties like Matta (red) and Chak-hao (black) compared to non-pigmented (NJ 72 and PB 1509). Comprehensive NQM developed indicated that Chak-hao, geographical indication (GI) rice has stout nutritional makeup in terms of phenolics (2.5 mg/g GAE), anthocyanins (0.65 g/kg), proanthocyanidins (54 mg/100 g), antioxidant activity (36 µmol TE/g) and resistant starch (4.13%) compared to Matta. The content of high-quality fatty acids like oleic (38.8%), linoleic (29%), and anthocyanin forms like cyanidin-3-glucoside (C3G)- 304 mg/Kg, delphinidin-3-glucoside (D3G)- 220 mg/Kg and peonidin-3-glucoside (P3G)- 120 mg/Kg was also most expressive in the black pigmented rice Chak-hao. Highly significant (p < 0.05) antioxidant activity and positive correlation with total phenolics, anthocyanins and proanthocyanidins content were most evident in pigmented varieties. Physicochemical attributes endorsing cooking time, water uptake ratio, grain elongation ratio, gruel solid loss and swelling ratio varied between 15–35 min, 2.17–3.2, 1.5–2.3, 0.28–1.25 and 1.75–2.66 respectively. The correlation between nutritional attributes endorsing antioxidant potential being strongly positive and most significant for Chak-hao, it could be the stellar addition for functional food industry as a nutritional supplement for addressing the ever-increasing pandemics like diabetes, obesity and other chronic diseases.Hide Abstract
Effects of different combinations of dietary starch and non-starch polysaccharides on intestinal functions, and lipid and glucose metabolism in weaned pigs.
Zhou, H., Chen, D. W., He, J., Mao, X. B., Yu, J., Zheng, P., Luo, J. Q., Luo, Y. H. & Yu, B. (2020). Journal of Animal and Feed Sciences, 29(3), 241-249.
The aim of the present study was to investigate the effects of different combinations of dietary starch and non-starch polysaccharides (NSP) on intestinal functions, and lipid and glucose metabolism in pigs. Fifty-four weaned pigs weighing 6.71 ± 0.52 kg were randomly assigned according to body weight and sex to 3 treatments with 6 replicates per treatment and 3 pigs per replicate, and were fed: T1 diet containing starch with amylose/amylopectin (AM/AP) ratio of 1:1 and NSP 3% (a mixture of inulin and cellulose in a ratio 1:1), T2 diet with starch of AM/AP ratio 2:1 and NSP 1% or T3 diet containing starch with AM/AP ratio of 1:2 and NSP 2%. Pigs were fed experimental diets for 28 days. It was shown that in animals fed T1 diet mRNA expression of glucagonlike peptide-2, zonula occludens 1 and occludin (P < 0.05) were up-regulated and tended to be increased the mRNA level of insulin-like growth factor-1 (P = 0.06) in colon, the activity of lactase in jejunum was increased (P < 0.05), mRNA expression of insulin receptor substrate 1 and glucose-6-phosphatase in liver were improved (P < 0.05), and the activity of lipoprotein lipase (P < 0.05) was decreased and the activity of malate dehydrogenase tended to be enhanced (P = 0.07) in longissimus dorsi muscle. Feeding T1 diet promoted the intestinal functions and improved to some extent lipid and glucose metabolism in pigs. So, carbohydrates combination of starch with AM/AP ratio of 1:1 and NSP 3% can be recommended for weaned pigs.Hide Abstract
Pea starch exhibits good expansion characteristics under relatively lower temperatures during extrusion cooking.
Rangira, I., Gu, B. J., Ek, P. & Ganjyal, G. M. (2020). Journal of Food Science, 85(10), 3333-3344.
Extrusion processing characteristics of pea starch were studied as impacted by various extrusion cooking processing variables, including, moisture content (15%, 17.5%, and 20% w.b.), temperature (120, 135, and 150°C), and screw speed (150, 200, and 250 rpm), in a co‐rotating twin‐screw extruder. Physicochemical properties such as radial expansion ratio (ER), unit density (UD), water absorption index (WAI), and water solubility index (WSI) were measured. ER of the extrudates ranged between 2.52 and 3.63. These values of ER were significantly high, although relatively lower compared to the highest values reported in the literature for corn and rice extrudates. The UD values for all the extrudates ranged from 0.12 to 0.35 g/cm3, WAI, and WSI values ranged from 10.98 to 12.10 g/g and from 0.12% to 7.73%, respectively. Both screw speed and moisture content had significant impacts on the ER (P < 0.01). The highest ER was observed for the extrusion cooking conditions of the lowest moisture content level (15%), lowest barrel temperature (120°C), and lowest screw speed (150 rpm). The cross‐sectional microstructure of the extrudates showed that the samples with a high ER had thick and elongated pores. The results of this study indicate that pea starch is a viable ingredient for making puffed extruded products.Hide Abstract
A submerged duckweed mutant with abundant starch accumulation for bioethanol production.
Liu, Y., Xu, H., Wang, Y., Tang, X., He, G., Wang, S., Ma, Y., Kong, Y., Yu, C. & Zhou, G. (2020). GCB Bioenergy, 12(12), 1078-1091.
Duckweed is one kind of promising bioenergy plant with prominent advantages such as fast growth rate and high starch content. However, almost all previous studies focused on the natural duckweed germplasms. In this study, heavy‐ion irradiation was used to establish a mutant library of Lemna aequinoctialis 6002, and one mutant named submarine‐1 (sub‐1) was screened, which could accumulate more starch but with smaller granules. Unexpectedly, under proper external growth conditions such as poor nutritional status and insufficient growth space, sub‐1 mutant would sink underwater due to formation of dense tissue structure and large amount of fine starch particles with the extension of cultivation time. The starch content in the sinking sub‐1 increased to over 45% (dry weight) and was 12% higher than the floating sub‐1, highlighting that submergence can be considered as a spontaneous and efficient indicator for screening of high‐starch duckweed. Additionally, the saccharification efficiency of starch and ethanol yield had increased in sub‐1 mutant compared to the wild type. Based on the unique characteristics of sub‐1 mutant, a cultivation model of submerged duckweed in a simulated aquaculture pond was designed to get more starch‐rich biomass, enabling effective production of renewable bioenergy.Hide Abstract
Gelatinization and pasta making conditions for buckwheat gluten-free pasta.
De Arcangelis, E., Cuomo, F., Trivisonno, M. C., Marconi, E. & Messia, M. C. (2020). Journal of Cereal Science, 95, 103073.
The formulations and the operative conditions of the processes involved in the production of buckwheat gluten free pasta were investigated. Buckwheat flour alone and/or in combination with maize and rice flours was used to make balanced formulations that, coupled with emulsifier and stabilizers (monoglycerides of fatty acids, propylene glycol alginate and/or flour of carob and guar), appropriate technologies (gelatinization of flour), and conventional pasta making process, allowed to achieve excellent nutritional and cooking quality properties. The presence of buckwheat flour in the formulation (49.2-99.4%) resulted in an experimental pasta with a high protein and dietary fiber content (values ranging from 8.9 to 11.2% d.w., and 8.9-14.4% d.w, respectively), hence making the innovative products suitable for celiac patients. The combined use of 0.1% propylene glycol alginate, 0.5% monoglycerides of fatty acids, and the gelatinization of mixed flour (buckwheat, maize, rice) allowed to obtain pasta with the highest cooking quality and texture.Hide Abstract
Probing the functionality of physically modified corn flour as clean label thickening agent with a multiscale characterization.
Carcelli, A., Masuelli, E., Diantom, A., Vittadini, E. & Carini, E. (2020). Foods, 9(8), 1105.
A multilevel and multianalytical approach, combining both traditional and unconventional analytical tools, was used to characterize two physically modified (heated and heated-extruded) corn flours to be used as a “clean label” food ingredient. Physical treatments decreased the resistant starch content and increased the water holding capacity and water binding capacity, more extensively in the product subjected to heating-extrusion, as compared to an untreated control. Heated-extruded flour had the highest ability to form homogeneous systems in cold water while all modified flours produced homogeneous systems when mixed with hot water. Systems made with heated-extruded flour were “more rigid” than other samples at all levels of investigation as they were harder (macroscopic) and had higher storage modulus (mesoscopic), as well as lower proton 1H mobility (molecular). Overall, the results highlighted the ability of the multiscale method to give a thorough overview of the flour–water interactions and showed highest water affinity of heated-extruded flour. Heated-extruded flour was then tested in three real-food industrial applications (carrot soup, tomato sauce and a meat patty), where it was successfully implemented as a clean label thickening agent.Hide Abstract
Physicochemical characterisation of starches from six potato cultivars native to the colombian andean region.
Pineda-Gomez, P., González, N. M., Contreras-Jimenez, B. & Rodriguez-Garcia, M. E. (2020). Potato Research, 1-19.
We isolated and investigated the starch of six potato cultivars (Solanum tuberosum), grown in the Andean region in the south of Colombia, to determine their physicochemical properties. The potato cultivars are known by their common names as Mambera, Ratona, Pastusa, Capiro, Unica and Roja-huila. The minerals, amylose content, water absorption and water solubility of the starches were evaluated. Morphology, crystalline structure, gelatinisation, thermal degradation and viscosity were also determined. The results showed that Capiro starch has a high mineral content. The apparent amylose and phosphorus contents in starch isolated from Mambera, Ratona and Pastusa were higher than those from Unica and Roja-huila. The starches with higher amylose content and better-defined peak in X-ray diffraction (XRD) (Mambera, Ratona and Capiro) had higher gelatinisation temperatures and took more time to reach the viscosity peak. All starches have hexagonal crystalline structure (B-type). The final viscosity of starches isolated from Mambera and Ratona was higher than that from Unica, Roja-huila and Pastusa due to their higher apparent amylose content.Hide Abstract