Sustainable production of pectin from lime peel by high hydrostatic pressure treatment

The application of high hydrostatic pressure technology for enzymatic extraction of pectin was evaluated. Cellulase and xylanase under five different combinations (cellulase/xylanase: 50/0, 50/25, 50/50, 25/50, and 0/50 U/g lime peel) at ambient pressure, 100 and 200 MPa were used to extract pectin from dried lime peel. Extraction yield, galacturonic acid (GalA) content, average molecular weight (M_w,ave), intrinsic viscosity [η]_w, and degree of esterification (DE) were compared to those parameters obtained for pectins extracted using acid and aqueous processes. Pressure level, type and concentration of enzyme significantly (p < 0.05) influenced yield and DE of pectin. Enzyme and high pressure extraction resulted in yields which were significantly (p < 0.05) higher than those using acid and aqueous extraction. Although pressure-induced enzymatic treatment improves pectin yield, it does not have any significant effect on M_w,ave and [η]_w of pectin extracts indicating the potential of high pressure treatment for enzymatic pectin production as a novel and sustainable process.     

High hydrostatic pressure assisted extraction of pectin from sugar beet pulp

This study aimed to investigate the effect of high hydrostatic pressure assisted extraction (HHPE) (250, 350 and 450 MPa at 40 °C for 5 min with/without acid addition) of pectin from sugar beet pulp and compare its properties with pectin obtained from conventional extraction (CE). Degree of esterification (DE), galacturonic acid (Gal-A) content, Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR) relaxometry experiments were performed on the obtained pectin powder. HHPE (12.23 ± 0.13%) doubled extraction yield compared to CE (6.43 ± 0.07%). Also, HHPE and acid addition were found to have a synergetic effect on the extraction. HHPE resulted in degradations in the polymer structure and reduced Gal-A content and DE. Pectin extracted with both methods was classified as low methoxyl pectin (LMP). According to the NMR Relaxometry results, HHPE decreased water holding capacity (WHC). In brief, HHP was shown to increase the pectin extraction yield and no changes in viscosity were observed at the concentrations studied (2 g/L).     

A study of factors affecting in-situ De-esterification of mango (Mangifera indica) pectin

De-esterification of mango peel pectin in situ by the action of the enzyme pectinesterase (PE) has been investigated. The rate of enzymic deesterification was highest between pH 8.5 and 9.5 with chemical deesterification also being important. In-situ PE activity declined with fruit ripening but remained relatively constant when assayed on citrus pectin. The most likely explanation for this difference is a change in suitability of the pectin substrate within the fruit during ripening. A reduction in the degree of esterification (DE) of the pectin to 36-42% was obtained following incubation of the mango peels at pH 8.5 for 90 min. A crude preparation of exogenous PE from mango peel and lime pulp was incubated at pH 8.5 with heat-treated (PE inactive) peel as a means of increasing the rate and extent of de-esterification. The PE activity of both these exogenous enzyme preparations was lower on the peel than that of the in-situ mango enzyme, but considerably higher on a hot-water-soluble fraction extracted from the peel. It is suggested that enzyme solubility and pectin accessibility are the major factors affecting in-situ de-esterification of pectin in mango peel.     

香蕉皮果胶萃取及果胶保鲜膜制备的研究

采用4种不同的方法萃取果胶,分析果胶结构,研究成膜因素对制备膜性能影响,探索制备膜的最佳工艺。结果表明,各种方法萃取的产品都为果胶,酸解盐析法萃取果胶效果最好,萃取率达1.311%;果胶底物浓度和变性淀粉用量影响制备膜的抗拉强度和断裂伸长率;影响制备膜抗拉强度的因素主要顺序为成膜助剂用量 >果胶浓度> 变性淀粉用量,但果胶+助膜剂+交联淀粉制备的膜其结构、抗拉强度都为最好,最佳制备膜的工艺参数为果胶底物浓度2.4%、助膜剂用量0.5%、变性淀粉用量1.0%。     

大豆皮果胶不同提取方法的研究

为比较不同提取方法对大豆皮果胶提取得率和产品性质方面的影响,以大豆皮为原料,分别采用水浴盐酸提取法、水浴草酸铵提取法和高压蒸汽草酸铵提取法从大豆皮中提取果胶,所得果胶提取液经乙醇沉析法得到果胶。分析比较了三种提取方法提取的果胶:提取得率、色泽、纯度、FTIR和蛋白质等指标,结果发现,草酸铵提取的果胶在色泽、纯度上优于盐酸提取的果胶,高压蒸汽加热方法能将提取时间缩短至20min。三种提取方法得到的果胶经过鉴别实验和FTIR分析都有明显的果胶特征,但果胶产品的纯度偏低,其中杂质主要是蛋白质。产品的水分和灰分含量都符合国家标准,但是其中的蛋白质含量都较高,有待进一步纯化。     

Extraction and characterization of a novel <Emphasis Type="Italic">Terminalia</Emphasis> pectin

This study reports the investigation into pectin present in Terminalia ferdinandiana—a native Australian fruit utilised in dietary supplement industry. Citric acid extraction was carried out to extract pectin from two commercially available T. ferdinandiana products—frozen puree and freeze-dried puree powder. The yields of the extracted pectin were measured at various pHs (2.0, 3.0 and 4.0) and times (30, 60 and 120 min) at 75 °C. Pectin yield ranged between 4.8 and 21%. Freeze-dried powder had a higher pectin yield compared to puree. Extraction at pH 3 for 120 min resulted in the highest yield from both puree (15%) and powder (21%). T. ferdinandiana pectins were found to have low methoxyl content with degree of esterification of 35.07 and 34.74% for puree and powder, respectively. Fourier transform infrared spectroscopy confirmed that the extracts were pectin.     

Utilisation of orange by-products—orange peel carotenoids

Carotenoids were extracted from fresh orange peel with various solvents. Acetone was the most efficient of the solvents tested. Two successive extractions with acetone after an initial washing with either acetone or methanol were adequate to remove 89% of the total carotenoids. The extracts were concentrated, the carotenoids transferred to hexane and a crude pigment concentrate was obtained by hexane evaporation. Water washings prior to acetone extraction eliminated the solvent-solvent transfer to hexane. The extraction residue was used for pectin recovery. Carotenoid removal from the peel did not affect the yield and quality of the pectin.     

酶法协同超声波辅助酸法提取柚子皮中果胶工艺条件优化

在单因素实验基础上,运用Plackett-Burnman试验设计确定对果胶得率有显著影响的因子,进一步采用Box-Behnken试验设计优化了柚子皮中果胶的提取工艺。结果表明,酶法协同超声波辅助酸法提取柚子皮中果胶的最佳工艺为:酶用量1.7%、酶解时间70 min、料液比1:25 g/mL、提取液pH2.0、超声功率260 W、提取温度83℃,提取时间50 min,在此条件下柚子皮中果胶得率达27.01%±0.91%。故采用酶法协同超声波辅助酸法能有效地提高果胶得率。     

酸法和酶法提取牦牛骨胶原蛋白的特性分析

以牦牛骨为原料,分别采用酸法和酶法提取胶原蛋白并进行理化性质分析。通过氨基酸组成、紫外光谱、傅里叶变换红外光谱、热收缩温度、十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（sodium dodecyl sulfate-polyacrylamide gelelectrophoresis,SDS-PAGE）和扫描电子显微镜图像分析对胶原蛋白进行比较。结果表明：2?种方法的提取物都为典型的胶原蛋白,在230?nm波长左右出现最大紫外吸收峰;酸溶胶原蛋白（acid-soluble collagen,ASC）和酶溶胶原蛋白（pepsin-soluble collagen,PSC）的热收缩温度分别为40.12?℃和40.94?℃,变性焓值分别为0.25?J/g和0.22?J/g;红外光谱及SDS-PAGE分析表明,ASC和PSC主要由α、β、γ三种亚基组分组成,属于I型胶原蛋白,且三股螺旋结构完整;扫描电子显微镜结果表明,2?种方法提取的胶原蛋白都保留了较为完整的纤维网状结构,但酸法提取的胶原蛋白结构分布相对均匀。综合来看,2?种方法所提胶原蛋白在理化特性上并无太大差别,但酶法提取的胶原蛋白得率较高,酸法提取成本较低。     

硒化低分子果胶的制备与结构表征及抗氧化活性

以苹果果胶为原料，经果胶酶酶解、硝酸-亚硒酸钠法超声辅助制备硒化低分子果胶，并以果胶、硒化果胶、低分子果胶作对照，采用体积排阻色谱-示差检测器-激光光散射联用技术、离子色谱法、傅里叶变换红外光谱、紫外光谱、热重分析、粒径和电位对其结构进行表征；采用氢化物-原子荧光光谱法检测硒含量，咔唑硫酸法检测半乳糖醛酸含量；利用体外实验研究其抗氧化活性以及对α-葡萄糖苷酶的抑制作用。结果表明：硒化低分子果胶的得率为（78.07±1.66）%，硒含量达（148.29±1.97）μg/g，半乳糖醛酸含量为（68.02±3.21）%；相对分子质量集中在8.905×103，在单糖组成上，硒化低分子果胶与果胶、硒化果胶、低分子果胶相同，主要由鼠李糖、阿拉伯糖、半乳糖、葡萄糖、木糖、半乳糖醛酸组成，但含量存在一定差异，红外光谱分析表明结构中含有Se＝O、C—O—Se键，实现了低分子果胶的硒化。紫外光谱在约200 nm波长处具有果胶多糖的吸收峰，经过酶解与硒化处理后，热稳定性降低，分散度变高，体系稳定性增强。果胶、硒化果胶、低分子果胶、硒化低分子果胶对羟自由基、超氧阴离子自由基的清除作用以及α-葡萄糖苷酶活力的抑制作用均较好，呈剂量效应关系，且硒化低分子果胶效果最强。     

超临界CO2萃取茯苓皮中三萜类化合物的分离纯化、鉴定

对茯苓皮中三萜化合物进行分离纯化及结构鉴定,采用超临界CO2法提取茯苓皮中的三萜化合物,通过溶剂萃取、柱层析色谱等现代分离分析手段对提取物进行分离纯化：采用紫外吸收光谱（UV）、红外吸收光谱（IR）、液质联用（LC-MS）技术对提取纯化物进行了结构解析,初步鉴定出16种茯苓三萜类化合物。     

炮制法对三叶木通果皮果胶提取及理化性质的影响

为提高三叶木通果皮果胶提取率和质量,探究不同炮制方法对三叶木通果皮果胶提取及其理化性质的影响.以未处理的三叶木通果皮生粉和炒制、砂制、醋制、酒制方法处理的果皮粉为原料,酸法提取得到果胶并进行结构表征,测定其果胶提取率、半乳糖醛酸质量分数、酯化度、乳化活性、乳化稳定性及抗氧化性.结果表明:醋制果胶提取率、半乳糖醛酸质量分...     

球磨联合碱辅助酶法改善淡竹叶水溶性膳食纤维的物化和功能特性

以淡竹叶为原料，采用酶法、球磨辅助酶法、碱辅助酶法和球磨联合碱辅助酶法4 种方法提取水溶性膳食纤维（soluble dietary fiber，SDF）。测定SDF得率以及通过高效液相色谱仪、纳米激光粒度仪、流变仪、扫描电子显微镜、傅里叶变换红外光谱仪、X射线衍射仪、差示扫描量热仪对4 种SDF的性质进行表征，并对其持水力、持油力、抗氧化性进行比较分析。结果表明：所有SDF均有明显的多糖特征和纤维素结晶类型，但其单糖组成和微观结构不同。球磨联合碱辅助酶法得到的SDF表现出最高的提取率（（30.03±1.03）%）和持水力（（4.86±0.1）g/g）、高黏度、最低的Zeta电位值（（－22.83±1.95）mV）；还具有疏松多孔的结构，较好的2,2’-联氮双(3-乙基苯并噻唑啉-6-磺酸)阳离子自由基清除活性（（49.40±0.93）%），表明具有良好的束缚水、抗氧化、形成凝胶的能力。     

超声辅助柠檬酸提取百香果果皮高酯果胶及其理化性质分析

为开发优质果胶资源,利用超声辅助柠檬酸法从百香果果皮中提取高酯果胶,采用单因素实验探讨了料液比、pH、提取时间、超声功率对果胶得率的影响,应用正交试验确定果胶的最优提取工艺,并对其理化性质进行比较分析。结果表明,提取过程中各因素对果胶得率的影响大小为:提取时间 > 料液比 > pH > 超声功率;最佳提取工艺为:料液比1:40（g/mL）、pH2.00、提取时间60 min、超声功率为180 W。该条件下百香果果皮果胶得率为13.07%。经理化性质测定,果胶干燥失重为5.92%、灰分含量为4.18%、酸不溶物含量为0.27%、pH为3.55、酯化度为72.32%,属于高酯化果胶。本研究结果可为百香果果皮果胶的工业化生产提供技术支撑。     

酸提工艺对果胶品质的影响

选用福建特产琯溪蜜柚果皮为原料,考察酸提工艺条件对果胶的酯化度、黏均分子质量和半乳糖醛酸含量的影响,设计正交试验L9(34)考察各因素的影响。结果表明:在试验范围内,酸提工艺条件对果胶的酯化度基本无影响,对半乳糖醛酸的含量有明显的影响,对果胶的分子质量影响最显著。9个不同试验条件下,酸提果胶的酯化度63.5%～63.8%,半乳糖醛酸含量74.2%～88.5%,果胶的黏均分子质量101～202ku。     

Characterization of pectin extracted from banana peels of different varieties

Pectins were extracted from banana peels of five different varieties using citric acid solution. The chemical characteristics of banana peel pectins were investigated and compared with citrus peel and apple pomace pectins which were extracted under the same extraction conditions to assess the potential of banana peels as an alternative source of commercial pectin. The yield of banana peel pectins ranged from 15.89 to 24.08%. The extracted banana peel pectins were categorized as high methoxyl pectin with the degree of esterification between 63.15 and 72.03% comparable to those of conventional pectin sources from citrus peel (62.83%) and apple pomace (58.44%). The anhydrouronic acid (AUA) content of banana peel pectins varied from 34.56 to 66.67%. Among various banana varieties being studied, pectin from Kluai Nam Wa variety had the highest AUA content (66.67%) which met the criteria for food additive pectin indicating its commercial significance as an alternative pectin source.     

Extraction and characterization of pectin from pomelo peel and its impact on nutritional properties of carrot jam during storage

Pectin was extracted using 0.1 N HCl at 90 °C for 120 min at pH 1.5 and 2.0 from pomelo peel and characterized in this study. Influence of various concentrations of extracted pomelo peel pectin on physicochemical, bioactive compounds, color, and sensory attributes of carrot jam during storage was also studied. Pectin extracted at pH 2.0 had higher ash content, equivalent weight, and total anhydrouronic acid content than that extracted at pH 1.0. Extracted pomelo peel pectin was categorized as high‐methoxyl pectin based on the degree of esterification. The β‐carotene and total phenol content were increased in jam after 90 days of storage. Ascorbic acid content decreased with increasing storage period. Jam prepared using commercial pectin had higher ΔE values than jam prepared using pomelo peel pectin. Physico‐chemical properties were influenced by pectin concentrations and storage time. Overall acceptability was similar for all samples on the basis of sensory evaluation. The results showed that pomelo peel might be used as a rich source of pectin and pomelo peel pectin could be used as an alternative to commercial pectins for carrot jam preparation.

Practical applications

Pectin is one of the main ingredients for jam and jelly making. Citrus fruits are main sources of pectin. Usually pomelo peels are discarded as waste materials. However, it could be a good source of pectin. In this article, pectin was extracted from pomelo peel and its application was observed as carrot jam during storage. Therefore, it can be concluded that extraction of pectin from pomelo peel might be used as an alternative to commercial pectin for carrot jam preparation.     

Combined Effect of High-Pressure and Conventional Heating on Pectin Extraction from Passion Fruit Peel

Passion fruit is one popular fruits in Brazil, and its annual production represents 70 % of the world production. About 60 % of fruit is mesocarp and epicarp (peel) and contains high levels of pectin that can be extracted using heating or alternative technologies. The purpose of the present work was to investigate the potential of high pressure to extract the pectin from passion fruit peel. The results showed that the extraction yield almost doubled (from 7.4 to 14.34 %) when high pressure was used as a pretreatment. The esterification degree and galacturonic acid of the pectin extracted were higher by 50 and 65 %, respectively. High pressure as a pretreatment was found to be an effective, time-saving, and eco-friendly method for the extraction of pectin from passion fruit peel.     

Extraction of pectin from passion fruit peel using moderate electric field and conventional heating extraction methods

Yellow passion fruit peel contains a high level of pectin that can be extracted from cell walls of plants. Direct boiling is a conventional method of extraction, which takes around 2 h to obtain a good yield of pectin. The long period of heating can produce degradation in the pectin, when the conventional heating is used to extract the pectin a lot of time and energy is spent. The purpose of this study was to explore the conventional and the moderate electric field extractions of pectin from passion fruit peel. The comparison of galacturonic acid content and esterification degree of the pectin obtained by different extraction methods indicated that similar values were obtained. Furthermore, moderate electric field is an efficient, timesaving, and eco-friendly method for the extraction of pectin from passion fruit peel, especially for pectin with a high esterification degree and galacturonic acid content higher than 65%.Industrial relevanceThis information is important for food industry since direct boiling, that is a conventional method of extraction, takes around 2 h to obtain a good yield of pectin and uses strong acid solutions. Also, today, this information which shows much interest in the food industry.     

Structural Characteristics of Extracted Collagen from Tilapia (Oreochromis mossambicus) Bone: Effects of Ethylenediaminetetraacetic Acid Solution and Hydrochloric Acid Treatment

Desalting is an important process of bone collagen extraction. In this present study, collagens were prepared from tilapia bone using acetic acid and pepsin. The extracted collagen was partially characterized. Prior to extraction, tilapia bone was desalted by soaking in ethylenediaminetetraacetic acid solution and hydrochloric acid. Thermo-gravimetric analysis, X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy were performed to analyze the structural characteristics. The extracted protein was classified as collagen by Fourier transform infrared spectroscopy, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and circular dichroism. Results showed that desalination with HCl was fast, but collagen yield was low. No acid-soluble collagen and only 0.5% pepsin-soluble collagen were obtained from HCl-treated fish bone. By comparison, the yields of acid-soluble collagen and pepsin-soluble collagen from ethylenediaminetetraacetic acid-treated fish bone were 3.5 and 6.0%, respectively. These values were observed higher than those from HCl-treated fish bone. In HCl-treated fish bone, the properties of collagen, such as amino acid composition, denaturation temperature, and molecular weight distribution, were different from those of collagen in ethylenediaminetetraacetic acid-treated fish bone. Collagens extracted from ethylenediaminetetraacetic acid-treated fish bone showed more integrated secondary structure. Therefore, ethylenediaminetetraacetic acid can be used more effectively than HCl to extract collagen from tilapia bone.