Retarding Retrogradation Research Articles

Improving cyclodextrin yield via retarding retrogradation of debranched starches during the preparation of cyclodextrin with cyclodextrin glycosyltransferase and pullulanase

Improving substrate utilization is crucial for industrial conversion of starch. The introduction of pullulanase in cyclodextrin (CD) production has improved substrate utilization. However, complete utilization of debranched starches has not been achieved, mainly due to the retrogradation of debranched starches and the inhibitory effect of CDs on pullulanase during the catalytic reaction. This study aimed to establish an efficient CD preparation system by regulating the substrate concentration and reaction temperature. A Bacillus thermoleovorans pullulanase (BtPul) was selected for investigation of its interaction with CDs through inhibition pattern assays, fluorescence spectroscopy, and molecular docking. Results clarified that CDs inhibited BtPul, with α-CD showing the highest inhibition, followed by β-CD and γ-CD. γ-CD inhibited BtPul through a mixed mode of competitive and noncompetitive inhibition, while the other CDs inhibited BtPul competitively. When pullulan was used as the substrate, increasing the substrate concentration weakened the inhibitory effect of CDs to some degree, while changes in reaction temperature only had a minor contribution. When BtPul and β-CGTase collaboratively converted 30% (w/v) starch substrate, an increase in reaction temperature improved the conversion rate of β-CD from 67.6% to 86.8%. Optimization of substrate concentration showed that high concentration starch substrate had an adverse effect on CDs yield due to retrogradation. The optimal yields of α-CD and β-CD produced by BtPul and α-/β-CGTases were 55.7% and 90.3%, respectively. This study provides a reliable method and reference for the efficient conversion of starch into CDs.

Regulation of multi-scale structures and retrogradation property of A- and B-type wheat starch granules with maltogenic α-amylase

Maltogenic α-amylase (MA) is widely used to modify starch for improving properties. In this work, A- and B-type starches were separated from wheat completely and submitted to MA hydrolysis. Firstly, research in morphological features (SEM) suggested that MA treatment did not destroy the granule integrity. Next, crystalline features from XRD and SAXS assay showed that MA treatment did not change the crystal form, but deceased crystalline sheet (dc) and amorphous sheet (da) thickness in both modified starches. And amorphous sheet was more severely destroyed at higher MA dosage than crystalline sheet. Then changes in molecule structure (HPAEC) showed that MA mainly acted on sides chains with degree of polymerization 12–24 in amylopectin for both starches, resulting in a reduce in peak, trough, and final viscosity obtained from RVA assay. At last, RVA and DSC assay showed that the short-term and long-term retrogradation were retarded in both modified starches. This range of techniques covered changes in multi-scale structures and retrogradation property resulted from MA treatment on both starches, which provided references for studying the changes in structures and properties of MA modified starch granules and provided an important method for retarding retrogradation of starchy foods without gelatinization processing.

Insight into the retardation of retrogradation of chestnut starch by heat-moisture treatment with flavonoids

With the concern of rapid retrogradation of chestnut starch, the effect of heat-moisture treatment (HMT) with flavonoids on the retrogradation of chestnut starch was studied. The retrogradation of starch could be inhibited by HMT combined with flavonoid addition up to 65.88%. Flavonoids with different structures showed significant differences in retarding retrogradation, which followed the order of epicatechin>epicatechin gallate>oligmeric proanthocyanidins. Structural analysis, infrared spectra and theoretical calculations showed that hydrogen bond interactions between starch and flavonoids retarded starch retrogradation by inhibiting the aggregation of starch molecules to form crystalline and aggregation structures. The retarding effect of flavonoids was related to their steric hindrance, flexibility and phenolic hydroxyl number. Epicatechin with minor steric hindrance and more flexibility favored its hydrogen bond interactions with starch, leading to the best retardation effect of starch retrogradation. This study would provide a theoretical and experimental basis for creating high-quality chestnut products.

Effects of Citrus Peel Hydrolysates on Retrogradation of Wheat Starch.

Retrogradation is the principal cause for bread staling and, therefore, it has attracted a lot of interest from the food industry. In this study, the inhibitory effect of citrus peel hydrolysates (CPH) on retrogradation of wheat starch (WS) in the presence of sucrose was investigated. The pasting properties showed that further addition of CPH caused a lower setback value than the addition of sucrose alone. Hardness of the gel, retrograded at 4 °C for five days, showed a similar tendency, which was reduced more in CPH addition than WS itself or sucrose addition alone. The low retrogradation enthalpy of the CPH including starch gel also indicated the positive effect of CPH on retarding retrogradation. These results suggested that incorporation of CPH in starch-based foods would be effective for inhibiting retrogradation, preventing the deterioration of the quality of food products.

Long-term retrogradation properties of rice starch modified with transglucosidase

The retrogradation properties of rice starch (RS) treated with transglucosidase (TG) were investigated. The degree of branching (DB) increased from 12.26 to 15.16% with increasing TG treatment time except for 20 h. The relative crystalline of the retrograded TG-treated starches decreased from 26.44 to 21.57% with increasing DB. While the crystalline peak intensity became narrower and sharpener due to the formation of a much more uniform crystal structure, hence resulting in a lower mobility of water. Also, the spin-spin relaxation time (T2) decreased with increasing DB. The T22 and T23 significantly decreased by 80.47 and 64.46%, respectively. The Avrami kinetics demonstrated that the retrogradation rate of rice starch was retarded due to the decrease of rate constant k after TG treatment. The study may provide a promising theoretical basis on retarding retrogradation of rice starch to improve the qualities and extend shelf life of the rice staple foods.

Enhanced Resistance to Amylolysis in Rice Kernels through Interaction with Chlorogenic Acid

In this study, rice-phenolic acid complexes were prepared by processing rice kernels in chlorogenic acid (CGA) solutions of different concentrations, followed by heating at different adsorption times. An adsorption treatment of 80 °C for 3 h effectively enhanced the complexation of rice samples with CGA (3.86 mg/g) and imparted antioxidant capacities to the complex. An apparent interaction between CGA and rice starch molecules was suggested by electrospray ionization mass spectrometry analysis. Our results revealed that rice samples were functionalized with CGA by modifying their physicochemical properties by increasing swelling ability (9.1%) and breakdown value (24.7%), and retarding retrogradation (−9.8%). The complexation of rice with a high dose of CGA could significantly reduce in vitro and in vivo starch digestibility by 41.9% and 23.0%, respectively, relative to control. This treatment is considered a potential way to confer rice with an increased resistance to digestion, along with desirable pasting properties.

쌀 품종이 스펀지케이크의 품질에 미치는 영향

This study aimed to compare the physicochemical properties of four rice varieties (‘Suwon 541’, ‘Suwon 542’, ‘Ilmi’, ‘Goami’) and their effect on the quality of sponge cake. The amylose contents in ‘Suwon 541’, ‘Suwon 542’, ‘Ilmi’, and ‘Goami’ were 19.69%, 18.15%, 18.62%, and 26.92%, respectively. The average particle size of ‘Suwon 542’ (21.87 μm) was significantly lower than that of the other varieties. The water absorption index (WAI) was highest for ‘Goami’ and the water solubility index (WSI) was highest for ‘Suwon 541’. The amylogram results indicated that initial pasting temperature was the highest for ‘Suwon 541’, where as the setback was the highest for ‘Goami’ and the lowest for ‘Ilmi’. ‘Suwon 541’ flour exhibited low volume and high cake hardness because of its high initial pasting temperature. Sponge cakes prepared with ‘Suwon 542’, which exhibited fine grain size and low WAI and WSI, had low hardness owing the low specific gravity of the batter and high cake volume. The low-setback ‘Ilmi’ flour was expected to have a retarding retrogradation effect on cakes. Sponge cakes prepared with ‘Goami’ flour possessed good characteristics although its high setback was expected to degrade the texture due to rapid retrogradation. The overall acceptability was the highest for ‘Suwon 542’ and ‘Ilmi’. Thus, ‘Suwon 542’ and ‘Ilmi’ were found to have a more positive effect on the quality of sponge cakes compared with the other varieties.

유산균 배양액과 계피추출물을 첨가한 sourdough bread의 저장 중 품질변화

This study investigated the changes in moisture content, pH, titrated acidity, Hunter’s color value, textural properties, and retarding retrogradation during the storage of sourdough bread made with lactic acid bacteria culture (LCBC) and cinnamon extract. The measurement results showed that the moisture content and pH of all the samples tended to decrease during the storage period; the CE0 sample exhibited the least variation in moisture content, whereas the CE100 sample showed the least variation in pH. The titrated acidity of all the samples increased during storage, but the extent decreased with the amount of cinnamon extract added. During the storage period, the redness, hardness, and gumminess increased; the whiteness, adhesiveness, springiness, and cohesiveness decreased; and the chewiness decreased after an initial increase. The retarding retrogradation was stronger for the group with LCBC and cinnamon extract, compared to that of the control, whereas the CE50 sample presented the strongest retarding retrogradation effect with the lowest Avrami exponent. These results suggested that the addition of LCBC and cinnamon extract during the manufacture of sourdough bread improved the storage period efficiency and retarding retrogradation.

Effects of preprocessing at low or ultralow temperatures combined with sodium alginate on retrogradation properties of normal cornstarch during chill storage

In this research, normal cornstarch (NCS) was preprocessed at low and ultralow temperatures, both with and without the addition of sodium alginate (AG), and then stored at 4 °C for 14 days to evaluate the retrogradation properties. The results showed that preprocessing with low (−18 °C) or ultralow (−80 °C) temperature could reduce the gel hardness, retrogradation enthalpy (ΔHr), the ratio of intensity at a value of 1047–1022 cm−1 (R1047/1022), and the relative crystallinity (RC) value of NCS. These four parameters were obviously decreased when NCS was preprocessed at low or ultralow temperature and combined with AG. The results suggested that the preprocessing combined with the addition of AG could retard NCS gel retrogradation much more effectively than the preprocessing by itself. These results provided a good method for retarding retrogradation of starch gel or starchy food.

Effect of black carrot (Daucus carota L.) flour on quality properties and retarding retrogradation by shelf-life of Sulgidduck (rice cake)

Black carrot (Daucus carota L.) contains anthocyanins, which are natural pigments that confer a bright red color. It has gained attention as a functional food that reduces the risk of diseases such as diabetes and heart disease and also demonstrates antioxidant activity. The goal of the present study was to identify the optimal proportion of black carrot flour for use in Sulgidduck (rice cake) in order to achieve high quality and retard retrogradation or tendency to become stale. Sulgidduck was prepared by replacing 0%, 0.5%, 1%, 2%, 3%, and 4% of the rice flour with black carrot flour; these preparations were designated as the control (without BC flour), BC0.5, BC1, BC2, BC3, and BC4.

호박잎 분말을 첨가한 설기떡의 품질 특성, 항산화 활성 및 저장 기간에 따른 노화 억제 효과

본 연구에서는 멥쌀가루를 이용하여 한국의 전통 떡인 설기떡을 제조한 후, 멥쌀가루의 0%, 1%, 2%, 3% 및 4% 비율의 호박잎 분말을 첨가하여 설기떡의 품질 특성, 항산화 특성 및 노화 억제 효과를 살펴보고자 하였다. 호박잎 설기떡의 수분 함량은 대조군(39.18%)과 비교하여 호박잎 분말 1%와 2% 첨가군에서 증가하였다가 3% 첨가군과 4% 첨가군에서는 감소하는 경향을 나타내었다. pH는 호박잎 분말의 첨가량이 증가함에 따라 4.50~6.16으로 유의적으로 증가하는 경향을 나타내었다(P0.05). 색도의 경우 호박잎 분말의 첨가량이 증가할수록 L값은 감소하고 b값은 증가하는 경향을 나타내었다. 호박잎 설기떡에서 경도는 대조군이 207.50 g/㎠, 호박잎 분말 1% 첨가군에서 186.10 g/㎠로 감소하였다가 2~4%에서 225.77~249.70 g/㎠로 다시 증가하였다. 탄력성은 81.72~88.02%로 유의적인 차이가 없었으며, 씹힘성과 부착성은 호박잎 분말 첨가량이 증가할수록 증가하는 경향을 나타내었다. 호박잎 분말을 첨가한 설기떡의 노화도 분석은 호박잎 분말 첨가군이 대조군(7.47)에 비해 높은 시간상수 값으로 노화 억제 효과가 있는 것으로 보였으며, 호박잎 분말 첨가군 중 2% 첨가군이 낮은 Avrami 지수 값으로 호박잎 첨가군 중 노화 억제 효과가 가장 크게 나타났다. 총 페놀화합물 및 ABTS 라디칼 소거 활성은 호박잎 분말의 첨가량이 증가함에 따라 증가하는 경향을 나타내었다. 7점 척도법을 이용한 소비자 기호도 조사 결과 색, 향, 촉촉함, 단맛, 씹힘성 및 전반적인 기호도에서 호박잎 분말 2% 첨가군이 가장 높은 기호도를 나타낸 반면, 4% 첨가군은 다른 시료들에 비해 낮은 기호도를 나타내었다. 이상의 결과로 미루어 보아 호박잎 분말의 첨가는 설기떡의 품질 특성 및 항산화 효과를 증진시킬 수 있는 것으로 여겨지며, 저장성을 고려한 노화 억제 효과를 위해서는 2%의 호박잎 분말의 첨가가 적합한 것으로 사료된다.

말티톨 첨가 구운떡의 품질 특성

This study investigated the quality characteristics of baked rice cake added with maltitol syrup. The hardness, adhesiveness, cohesiveness, gumminess, and chewiness of baked rice cake significantly decreased (P<0.05) according to the level of added maltitol syrup. Hunter"s color values of baked rice cake did not differ significantly according to the level of added maltitol syrup. Sensory evaluation indicated that appearance, moistness, chewiness, hardness, and overall acceptance of baked rice cake prepared with added maltitol syrup were improved compared to those of baked control rice cake. Hunter"s color values and texture properties of baked rice cake added with 10% maltitol syrup were compared with those of baked control rice cake during storage at room temperature for 3 days. Hunter"s color L values of baked rice cake decreased during storage, whereas a and b values increased. The rate of hardness increase in baked rice cake with maltitol syrup was lower than that in baked control rice cake during storage. The Avrami exponents (n) of baked control rice cake and baked rice cake added with 10% maltitol were 2.418 and 2.098, respectively. The time constants (1/k) of the former and latter were 43.860 and 60.976, respectively. Overall, addition of 10% maltitol syrup improved the texture, sensory properties, and retarding retrogradation of baked rice cake.

말토올리고당과 변성 전분 혼합 사용 떡의 품질 특성

The quality characteristics of Korean rice cakes (Karedduk) with a mixture of maltooligosaccharide and OSA (octenyl succinic acid starch) added, after 2 and 24 hr of storage at <TEX>$5^{\circ}C$</TEX>, was analyzed. A central composite design was used for arrangement of treatment. The two independent variables selected for retarding retrogradation analysis were amounts of maltooligosaccharide (x) and OSA (y). Maltooligosaccharide was added at 0, 3, 6, 9, and 12% levels, and OSA added at 0, 0.3, 0.6, 0.9, and 1.2% levels, to dry rice flour. The texture properties analysis using a Texture Analyzer revealed that the springiness and cohesiveness (p<0.01), chewiness, gumminess and hardness (p<0.001) were significantly different after 24 hr of storage at <TEX>$5^{\circ}C$</TEX>. The effect of retarding retrogradation of Korean rice cakes with added mixtures of maltooligosaccharide and OSA showed an increasing trend as the amount of maltooligosaccharide increased. Overall, the instrumental texture properties were highly correlated with the sensory characteristics. These results suggest that adding a mixture of 6% maltooligosaccharide and 0.6% OSA to Korean rice cakes (Karedduk) is effective for retarding retrogradation.

Thermoplastic starches: Properties, challenges, and prospects

AbstractThermoplastic starch (TPS) polymers were reviewed in this article. This review was categorized into the following studies: the role of starch as a thermoplastic polymer, transformation and melting mechanisms, plasticization and plasticizers, reactive extrusion (REX) and modifications, retrogradation, biodegradability, filler and blenders, and nano‐particle incorporation in thermoplastic starch. This categorization allows us to understand the developments in this field in recent years and shows that the major challenges in the future are reducing sensitivity to moisture and retarding retrogradation of the thermoplastic matrix. Moreover, nano‐particles such as clay can be used in TPS matrices to overcome these disadvantages.

프락토올리고당과 유화제 혼합사용 가래떡의 텍스처와 관능적 묘사 특성

본 연구는 중심합성계획법에 따라 쌀가루 기준으로 프락토올리고당(95%)은 0, 3, 6, 9 또는 12% 농도로 첨가하고, 유화제 SSL-90은 0, 0.3, 0.6, 0.9 또는 1.2% 농도로 혼합사용하여 제조한 가래떡을 5oC 저장 2시간과 24시간 후 텍스처 변화를 Texture Analyzer에 의해 측정하였고, 5oC 저장 2시간과 24시간 후 관능적 묘사특성 효과를 분석하였다. 떡의 텍스처 변화에서 제조 2시간과 24시간 후 실험군간 차이가 있었던 특성은 씹힘성, 검성 및 경도였으며, 탄성과 응집성 특성에서는 각 실험군 간의 차이가 없었다. 관능적 묘사특성 효과분석에서는 유화제 SSL-90의 함량이 높을수록 경도가 낮은 반면 프락토올리고당(95%)의 함량이 높을수록 단맛이 증가하는 경향을 보여주었다. 그리고 떡의 텍스처 변화와 관능적 특성 간의 상관관계를 분석한 결과 기계적 텍스처 변화 중에서 씹힘성, 검성, 부착성 및 경도 등은 관능적 특성 부착성, 경도 및 응집성과 높은 상관관계를 나타내었다. 따라서 프락토올리고당(95%)과 유화제 SSL-90의 혼합사용의 경우 프락토올리고당(95%) 9%와 유화제 SSL-90 0.9% 농도 수준으로 혼합 첨가하면 기계적 텍스처 변화와 관능적 특성의 변화를 보여주어 저장 중 떡의 노화 억제에 효과가 있는 것으로 나타났다.

올리고당 첨가 가래떡의 텍스처 변화와 노화 억제 분석

가래떡의 노화 특성을 분석하기 위하여 갈락토올리고당(50%)과 말토올리고당을 쌀가루 기준으로 각각 10% 농도로 첨가하여 쌀가루의 pasting 특성을 측정하였고, 가래떡을 제조하여 5℃ 냉장 보관하면서 0, 2, 6, 24 및 30시간 경과 후 텍스처의 변화를 Texture Analyzer에 의해 측정하여 실험군의 떡을 무첨가군 떡과 비교하였다. 그리고 가래떡의 노화도는 텍스처 특성 중에서 0, 2, 4, 6, 22, 24, 28 및 30시간 경과 후 경도의 변화를 이용하여 Avrami 방정식에 따라 실험군의 떡을 무첨가군 떡과 비교하였다. 갈락토올리고당(50%)과 말토올리고당을 첨가한 실험군의 pasting 특성에서 peak(P) viscosity는 무첨가군에 비해 낮게 나타났고, hot paste viscosity(H)는 높게 나타났다. Breakdown(P-H)과 consistency(C-H)는 모든 실험군에서 무첨가군에 비해 낮게 나타나 올리고당을 10%를 첨가한 실험군에서 노화억제 효과가 있는 것으로 나타났다. 텍스처 특성 중 경도의 경우 실험군은 무첨가군에 비해 감소하는 경향으로 노화를 억제하는 효과를 보여 주었다. Avrami 방정식에 따른 노화 특성 분석 결과는 Avrami(n)지수 값은 무첨가군보다 약간 높은 범위였으나 노화의 속도를 나타내는 시간상수(1/k)는 무첨가군 떡의 경우 43.29이었고 실험군의 경우는 82.64에서 84.75 범위로 무첨가군에 비해 그 값이 높았으며 노화속도가 느린 것으로 나타났다. 따라서 무첨가군에 비교하여 실험군 모두 경도가 낮고 노화 진행속도가 느린 것으로 나타나 갈락 토올리고당(50%)과 말토올리고당을 가래떡 제조 시 10% 수준으로 첨가하면 노화억제 효과가 있는 것으로 확인되었다.

Comparison of the effect of sugars on the viscoelastic properties of sweet potato starch pastes

SummaryViscoelastic properties of sweet potato starch (SPS) pastes (5% w/w) were studied in the presence of various sugars (sucrose, glucose, fructose, and xylose) at different concentrations (0, 10 and 20%) by small‐deformation oscillatory measurements. Dynamic frequency sweeps at 20 °C indicated that all SPS–sugar mixtures were more elastic than viscous with storage moduli (G′) higher than loss moduli (G′′) at all values of frequency with a frequency dependency. Dynamic moduli (G′ and G′′) values increased with the increase in sugar concentration from 10 to 20%. Changes in the dynamic moduli were more pronounced with xylose in comparison to the control (no sugar) and other sugars. G′ values as a function of ageing time (10 h) at 4 °C continuously increased with time during ageing without a plateau region. In general, G′ values of SPS–sugar mixtures during ageing decreased in the following order: pentose (xylose) &gt; hexose (glucose and fructose) &gt; control &gt; disaccharide (sucrose), indicating that the xylose had the greatest ability in retarding retrogradation of SPS.

반응표면분석을 이용한 트레할로스와 변성전분 혼합사용 떡의 품질 특성

Texture and descriptive sensory characteristics of a Korean rice cake (Karedduk) added with mixture of trehalose and Sun-Tender were investigated after 2, 24, and 48 hrs of storage at 5℃. A central composite design was used for treatment arrangement. The trehalose were added in 0, 3, 6, 9 and 12% levels and Sun-Tender added in 0, 0.3, 0.6, 0.9, and 1.2% levels to dry rice flour. The mixture amounts of trehalose and Sun-Tender on texture and descriptive sensory characteristics of a Korean rice cake (Karedduk) were optimized using response surface methodology (RSM). The two independent variables selected for the RSM were amounts of trehalose (X₁) and amounts of Sun-Tender (X₂). The predicted value at stationary point or a minimum for texture hardness by RSM was found as 591.5440 after 24 hrs of storage at 5℃. Also the adhesiveness, hardness, cohesiveness and sweetness by sensory characteristics were significantly different as compared to the control. The results suggested that a Korean rice cake (Karedduk) added with mixture of trehalose and Sun-Tender can be made from the mixture amounts of trehalose 9.5826% and Sun-Tender 0.2216% in retarding retrogradation.

가래떡 노화 억제에 대한 당류 물질의 효과

Retarding retrogradation of a Korean rice cake (Karedduk) added with carbohydrate materials after 0～30 hrs of storage at 5℃ were investigated by Avrami equation using textural characteristics. Carbohydrate materials such as powdered sugar, trehalose, fructooligosaccharide (95%), isomalto, healtholigo, and galactooligo-saccharide (50%) were added in 0, 1, 5 or 10% levels on dry rice flour. In the amylogram, the breakdown (P-H) and consistency (C-H) for Karedduk added with carbohydrate materials were lower than those of the control. Decrease in the Avrami exponent (n) and increase in the time constant (1/k) of Karedduk added with carbohydrate materials during storage determined by Avrami equation were important comparison factors to the control in terms of retrogradation rate analysis. The Avrami exponent (n) for control, fructooligosaccharide (95%) 10% and healtholigo 1% addition were 2.415, 1.977 and 3.297, respectively. The time constant (1/k) for fructooligosaccharide (95%) 5% and healtholigo 1% addition were lower than the control. Lastly, Karedduk added with carbohydrate materials, except for fructooligosaccharide (95%) 5% and healtholigo 1% addition, was effective in retarding retrogradation.

Effects of hydrocolloids and freezing rates on freeze–thaw stability of tapioca starch gels

Retrogradation in frozen starch gels was affected by hydrocolloid addition and freezing rate. A freeze–thaw cycle (FTC) treatment was used in this study to determine the effects of hydrocolloids and freezing rates on the stability in tapioca gels. Analysis of retrogradation of starch gels, determined by FTC and based on syneresis measurements, showed that xanthan gum (XG) at 0.25% and 0.50% concentrations was more effective in reducing syneresis than locust bean gum and konjac-glucomannan. Guar gum had no effect in retarding retrogradation of tapioca starch gel. When various freezing rates were used, the results showed that a fast freezing rate (2.30 °C/min) could prevent changes that occurred due to retrogradation more than medium (0.90 °C/min) and slow (0.06 °C/min) freezing rates. The best conditions for the reduction of starch retrogradation in this study was the addition of 0.50% XG with the freezing rate at 2.30 °C/min.