脱脂脱蛋白处理对小麦A、B淀粉理化性质的影响

为阐明脂类和颗粒结合蛋白对小麦A、B淀粉理化和结构性质的影响,以豫麦49-198为试验材料,采用面团法制备小麦淀粉,沉降法分离小麦A、B淀粉,并对其进行脱脂脱蛋白处理,研究了处理前后小麦A、B淀粉组成、颗粒结构、溶解度与膨胀度、糊特性、热特性等性质的差异。结果表明:与未处理的小麦A、B淀粉相比,脱脂脱蛋白处理后小麦A、B淀粉颗粒表面较光滑,分散程度较均匀,偏光十字的位置和形状无显著性差异,清晰度显著增加;溶解度和膨胀度随温度的增长趋势显著增加;起始温度、峰值温度、终值温度、透明度、峰值黏度、衰减值、回生值显著增加;冻融稳定性、峰值时间显著降低;热焓值无显著变化。这为小麦A、B淀粉更好的应用提供理论参考。     

脱脂对三种豆类淀粉理化性质的影响

为研究脂类化合物对豆类淀粉理化性质的影响,以红豆、鹰嘴豆、蚕豆为材料,采用湿法分离淀粉并做脱脂处理,分析了脱脂前后三种豆类淀粉颗粒特性、热特性、淀粉糊特性存在的差别。结果表明：与脱脂前相比,脱脂处理后三种淀粉的偏光十字更加明显,溶解度、膨胀度和透明度升高,热焓值降低,冻融稳定性变差,淀粉晶型、起糊温度、峰值黏度、终值黏度、破损值、回生值和凝沉性无明显变化。脱脂处理使三种豆类淀粉的溶解度、膨胀度、糊透明度得到改善。     

糯玉米粉、淀粉和脱脂淀粉的理化特性研究

以4个糯玉米品种为材料,比较分析了糯玉米粉、淀粉(脱蛋白)和脱脂淀粉(脱蛋白脱脂)的理化特性.结果表现,脱蛋白或脱蛋白脱脂处理不改变材料的结晶类型,各材料均表现为典型的"A"型衍射图谱.理化特性在糯玉米粉、淀粉和脱脂淀粉间存在显著差异.结晶度、膨胀势、回复值、峰值时间和糊化温度以糯玉米粉最高,脱脂淀粉最低;溶解度、峰值黏度和谷值黏度以淀粉最高,米粉最低;透光率以脱脂淀粉最高,米粉最低;但4个糯玉米品种的终值黏度变化趋势不甚明显.     

脱脂对3种豆类淀粉理化性质的影响

为研究脂类物质对豆类淀粉理化性质的影响,以红豆、鹰嘴豆、蚕豆为材料,采用湿法分离淀粉并做脱脂处理,分析了脱脂前后3种豆类淀粉颗粒特性、热特性、淀粉糊特性存在的差别。结果表明:脱脂后3种淀粉的溶解度、膨胀度和糊透明度升高,热焓值降低,冻融稳定性变差,颗粒形貌、偏光十字、淀粉晶型、起糊温度、峰值黏度、终值黏度、破损值、回生值和凝沉性无明显变化。脱脂处理使3种豆类淀粉的溶解度、膨胀度、糊透明度得到改善。     

脱蛋白或脱脂对薏苡淀粉糊化和体外消化特性的影响

以薏苡为材料,制备脱淀粉颗粒相关蛋白(starch granule-associated proteins,SGAPs)、脱脂和脱SGAPs脱脂薏苡淀粉,探究了脱SGAPs和脱脂对薏苡淀粉糊化和体外消化特性的影响。结果表明,脱SGAPs和脱脂提高了薏苡淀粉的膨胀势、溶解度、快消化淀粉和慢消化淀粉,降低了1 045 cm^-1与1 022 cm^-1处峰强度比值、峰值黏度、谷值黏度、崩解值和抗性淀粉。脱SGAPs显著提高了薏苡淀粉的糊化转变温度、糊化焓,显著降低了糊化起始温度。脱SGAPs对淀粉短程有序结构和消化特性的影响大于脱脂,脱脂对薏苡淀粉的热力学性质无显著影响,脱SGAPs和脱脂对淀粉的晶型无显著影响。研究结果对于了解薏苡淀粉特性以及薏苡淀粉在食品加工中的应用具有潜在价值。     

青稞淀粉和小麦淀粉的理化性质比较研究

研究了青稞淀粉的理化性质,包括淀粉的颗粒形态、粒度分布及淀粉糊透明度、溶解度、膨胀力和糊化特性,并与小麦淀粉性质进行比较。结果表明:青稞淀粉颗粒的平均粒径大于小麦淀粉颗粒的平均粒径,青稞淀粉颗粒大小和形状分布均匀;青稞淀粉糊透明度大于小麦淀粉糊,但在储藏过程中,青稞淀粉糊透光率变化显著;青稞淀粉的溶解度和膨胀力均大于小麦淀粉糊,这与小麦淀粉中小颗粒淀粉含量较多有关;与小麦淀粉的糊化相比,青稞淀粉成糊温度低,糊化容易,但峰值黏度低,衰减值大,热糊稳定性差,回生值大,冷糊稳定性差,易老化。     

脱脂对糯玉米淀粉热力学特性的影响

以4个糯玉米淀粉为材料,对其进行脱脂处理,分析了其对淀粉热力学特性的影响。结果表明,脱脂使淀粉中的磷元素含量显著降低,导致淀粉的起始温度、峰值温度、终值温度、峰值指数和热焓值降低,糊化范围扩大。淀粉和脱脂淀粉糊化冷藏后发生回生,表现为脱脂增加了回生淀粉的热焓值,进而增加了淀粉的回生值和峰值指数,而起始温度、峰值温度、终值温度和糊化范围受脱脂影响较小。淀粉和脱脂淀粉的热焓值存在显著的基因型差异,淀粉的热焓值以渝糯408最低,脱脂淀粉的热焓值以郑彩糯1号最低。淀粉回生后热焓值和回生值差异较小,而脱脂淀粉回生后热焓值和回生值以YA30142最高,郑彩糯1号最低。     

筛分细度对糯玉米淀粉理化特性的影响

以糯玉米为材料,分析了不同筛分细度(100目、200目和400目)对淀粉理化特性的影响。结果表明,随着分样筛孔径的变小,淀粉中小颗粒的比例增多,结晶度升高,但淀粉颗粒并未受到破坏。淀粉的膨胀势和溶解度以过细筛(400目)处理下最大。筛分细度对淀粉的峰值时间、糊化温度和析水率影响较小,但细筛使其他黏度特征值显著升高。DSC研究表明,起始温度、峰值温度和终值温度以过200目筛时较高,过100目和400目时较低,过细筛(400目)处理下淀粉热焓值较高,回生值较低。     

超声处理对橡子淀粉理化性质的影响

该研究综合运用显微、流变、质构等手段,分析超声处理对橡子淀粉结构和理化性质的影响。结果表明,超声处理会导致橡子淀粉分解,淀粉颗粒表面亦出现凹陷,其程度与超声处理时间正相关。超声处理后淀粉颗粒的偏光十字现象虽然保留,但颗粒粒径增大,出现聚集。随着超声时间的延长,淀粉糊的透明度下降,但其冻融稳定性、沉降体积、温度大于75 ℃时的溶解度和膨胀度显著改善。淀粉糊的峰值黏度、最低黏度、终值黏度均随着超声时间的延长而下降,但糊化温度保持稳定,且适当的超声波处理可提高淀粉凝胶强度。     

黄原胶协同干热变性对紫薯淀粉特性的影响

为开发强度高、透明度好且阻水能力优的可食性淀粉膜,本试验添加黄原胶对紫薯淀粉进行干热变性处理,研究其产物特性的变化。结果表明:黄原胶协同干热变性处理后的紫薯淀粉颗粒略微膨胀,大小不均一且发生粘连现象;糊化起始温度略有降低,峰值黏度与终值黏度均升高,热稳定性提高;淀粉糊的冻融稳定性显著提高,溶解度和膨胀度降低,且透明度有所降低;淀粉糊的流变曲线表现为逆时针环状,屈服应力明显增大,其形成的凝胶呈现固体特征,储能模量G'增加,剪切结构恢复力显著提高;淀粉属C-型晶体,干热处理前后淀粉的X-射线衍射图谱无明显变化,但干热变性处理使淀粉结晶度增大。因此,添加黄原胶对紫薯淀粉进行干热变性,可使产物的特性发生明显改变。     

Physicochemical properties of thermal alkaline treated pigeonpea (Cajanus cajan L.) flour

Thermal alkaline treatment, normally used for corn, was applied to pigeonpea grains. Starch granules were isolated using wet milling and alkaline treatments. Effects of the calcium hydroxide [Ca(OH)₂] concentration in the range of 0–1% (w/v) on granule structure, crystalline structure, chemical composition, and physicochemical, thermal, and pasting properties of isolated starch granules were determined. Compared to native samples, thermal alkaline treated samples had higher protein, lipid, calcium, and phosphorus contents, but lower starch and amylose contents. Thermal alkaline treatment increased starch granular size and gelatinization temperatures, but decreased relative crystallinity, gelatinization enthalpy, swelling power, solubility, amylose leaching, and the pasting viscosity. Amylose-lipid complexes were not found in thermal alkaline treated flours. As the Ca(OH)₂ concentration increased, the amylose content, relative crystallinity, gelatinization temperature, and enthalpy also increased, but the swelling power, solubility, amylose leaching, and paste viscosity decreased. A higher Ca(OH)₂ concentration produced more stable starch granules that resisted re-gelatinization.     

超声波处理对马铃薯全粉理化性质和消化特性的影响

以马铃薯全粉为原料,研究超声处理对马铃薯全粉理化性质和消化特性的影响。结果表明:超声处理使得马铃薯全粉的结晶度增大,晶体结构明显改变,溶解度、膨胀度、吸油性、崩解值、糊化温度和消化特性显著降低。随着超声波处理时间的延长,马铃薯全粉的结晶度、峰值黏度、谷值黏度和最终黏度先升高后降低。随着超声波处理时间的延长,快消化淀粉(RDS)含量降低,慢消化淀粉(SDS)和抗性淀粉(RS)含量升高。研究表明,超声处理显著影响马铃薯全粉的理化性质和消化特性(P0.05)。     

不同物理方法处理对碎米中淀粉特性的影响

采用挤压、微波、超声波三种物理方法对水分含量18%的碎米淀粉进行处理,研究分析碎米淀粉经物理方法处理前后的理化性质和结构变化。结果表明,碎米淀粉经微波和超声处理后酶解力增加,糊化黏度下降,而溶解度、膨胀力、糊化温度和直链淀粉含量变化不显著;两种淀粉颗粒表面棱角减少,淀粉颗粒晶型基本没有发生变化,淀粉结晶区降低。挤压后的碎米淀粉变化较大,颗粒形状为片状,凝沉性强,1.0 h后体积仅为3 mL,糊化温度明显降低至55.0 ℃,直链淀粉含量增长为30.75%,溶解度强,为0.59%,酶解力达到45%,X-射线主要衍射峰的强度降低。     

马铃薯抗性淀粉理化性质的研究

以马铃薯原淀粉为对照,研究了纤维素酶-压热法制备的马铃薯抗性淀粉的理化性质。结果表明,马铃薯原淀粉颗粒呈椭球形,表面光滑;而抗性淀粉的颗粒状结构消失,形成了连续的致密结构,表面不再光滑。红外光谱分析表明,抗性淀粉分子中未出现新的基团,只较原淀粉形成了更多的氢键。马铃薯原淀粉的分子晶型为A型,整体结晶度为22.82%;抗性淀粉的分子晶型为B型,整体结晶度为29.64%。马铃薯抗性淀粉的溶解度、透明度远远低于原淀粉;膨润度、持水性优于原淀粉。抗性淀粉的沉降速度较快,沉降性比原淀粉强。原淀粉糊化温度为65.8 ℃,峰值黏度可达到10 770 mPa·s;而抗性淀粉其糊化温度高于95 ℃。     

Physicochemical Properties of Canna edulis Ker Starch on Heat-Moisture Treatment

Canna edulis Ker starch was modified by heat-moisture treatment at moisture levels ranging from 18 to 27 g/100 g starch and its physicochemical properties were investigated. Amylose content, swelling power, solubility as well as water and oil absorption capacity in native starch were higher than in all treated starches. However, alkaline water retention and acid susceptibility of native starch were lower, along with different extent of amylose leaching. The result in the X-ray diffraction measurement revealed that the crystalline type of the starch gradually changed from B-type to A-type, and the degree of crystallinity changed. Investigation on thermal properties showed that the gelatinization enthalpy decreased, whereas the onset temperature, peak temperature, concluding temperature and transition temperature range increased in modified starch than in native starch. In addition, all modified starches exhibited remarkably low values of peak viscosity, hot pasting viscosity and final viscosity, compared to those of native starch.     

Prediction of sweetpotato starch physiochemical quality and pasting properties using near-infrared reflectance spectroscopy

A rapid predictive method based on near-infrared reflectance (NIR) spectroscopy (NIRS) was developed to measure sweetpotato starch physiochemical quality and pasting properties. The starch samples were scanned by NIRS and analyzed for quality properties by reference methods, respectively. Results of statistical modeling indicated that NIRS was reasonably accurate in predicting amylose content (AC), amylose percent (AP), total starch content (TSC), protein content (PRC), phosphorus content (PHC), solubility (SOL), swelling power (SP), average granule diameter (AGD), big granule percent (BGP), small granule percent (SGP), crystallinity (CRY), peak viscosity (PKV), hot paste viscosity (HPV), setback (SB), and pasting temperature (P_temp) with high coefficients of determination (RSQ = 0.85–0.92) and relatively low standard errors of prediction. The results showed that NIR analysis was sufficiently accurate and effective for rapid evaluation of starch physicochemical properties in sweetpotato. The NIR-based protocol developed in this study can be used for screening large number of starch samples in food enterprises and sweetpotato breeding programs.     

Effect of heat-moisture treatment on rice starch of varying amylose content

The effect of heat-moisture treatment (HMT) on the properties of rice starches with high-, medium- and low-amylose content was investigated. The starches were adjusted to 15%, 20% and 25% moisture levels, and heated at 110 °C for 1 h. The swelling power, solubility, pasting properties, morphology, enzymatic susceptibility and X-ray crystallinity of the starches were evaluated. HMT reduced the swelling power and solubility of the starches. The strongest effect of HMT occurred on the high-amylose starch; the pasting temperature was increased and the peak viscosity, breakdown, final viscosity and the setback were reduced. HMT increased the starch’s susceptibility to α-amylase and promoted a reduction in the starch relative crystallinity.     

Comparison of Morphology and Physicochemical Properties of Starch Among 3 Arrowhead Varieties

Arrowhead (Sagittaria trifolia var. sinensis) is a source of starch worldwide, but arrowhead starch has been rarely studied. In this work, starch was separated from arrowhead corm. The morphology and physicochemical properties of starch were then investigated and compared among 3 different arrowhead varieties (Purple‐corm, Hongta, and Japanese). Results showed that starches from the 3 varieties similarly featured an oval shape containing a visible polarization cross, a C_A‐type crystalline structure, and an ordered structure in the external granule region. However, starch content, granule size, crystal characteristics, and pasting properties differed among the 3 varieties. Japanese arrowhead exhibited the highest starch content and degree of ordered structure in the external granule region, as well as onset, peak, and final gelatinization temperature. Purple‐corm arrowhead starch demonstrated the highest amylose content and relative degree of crystallinity, smallest granule size, and lowest swelling power and solubility. Purple‐corm arrowhead starch also showed the highest gelatinization enthalpy, as well as peak, trough, final, and setback viscosities. This starch further presented the lowest breakdown viscosity and degree of hydrolysis by HCl and porcine pancreatic α‐amylase. These findings can provide useful references for arrowhead variety selection in food and nonfood industries.     

Physicochemical, crystallinity, pasting and morphological properties of bean starch oxidised by different concentrations of sodium hypochlorite

The effect of bean starch oxidation at different active chlorine concentrations (0.5%, 1.0% and 1.5%) on the physicochemical, crystallinity, pasting and morphological properties of starch was investigated. The carbonyl content, carboxyl content, starch colour, swelling power, solubility, gel hardness, X-ray crystallinity, pasting properties, gelatinisation characteristics and morphology of the starches were evaluated. The bean starch oxidised with 0.5% active chlorine had the characteristic of a slightly crosslinked starch. As compared to the native and 0.5% active chlorine-oxidised starches, active chlorine at 1.0% and 1.5% increased the carbonyl content, carboxyl content and solubility of the starches. Moreover, these concentrations of active chlorine decreased the swelling power, gel hardness, relative crystallinity, breakdown, peak viscosity and setback, as compared to the native and 0.5% active chlorine-oxidised starches. The starch granules oxidised with 1.5% active chlorine had imperfections in their structure, and its surface appears to be rougher than the other granules.