甘薯块根质构特性的研究进展

甘薯是重要的粮食、饲料及食品工业原料作物, 质构特性是甘薯品质的重要组成部分, 是评估其质量优劣的重要指标, 它直接影响块根食用品质以及产后加工途径、技术及其利用价值。质构特性是近年来甘薯研究的一个热点。本文对甘薯块根质构测定及评价方法、影响质构特性变化的各种因素作用等多个方面研究结果进行较为系统的综述, 对甘薯质构研究中存在的问题以及今后的发展方向和前景进行了讨论和分析, 这对于进一步深入研究甘薯以及其他根茎作物质构特性, 以及质构特性育种改良、产品品质提高具有重要理论和实践指导意义。     

改性甘薯淀粉及其在食品工业中的应用研究进展

甘薯淀粉常作为粉丝和粉条等食品加工原料,具有稳定和增稠作用。但受其固有性质的限制(如热稳定性差、淀粉糊透明度低等),难以满足现代食品工业发展的需求,而改性(如物理法、化学法、酶法及复合法等)能赋予甘薯淀粉良好的功能、流变学和加工特性(如抗老化性、淀粉糊透明度高、凝沉性小、冻融稳定性好、抗酸性和成膜性好等),可用于改善食品的物化特性、质构特性及食用品质。该文首先分析了甘薯淀粉的结构及性质,并总结了改性方法,最后概述了甘薯淀粉在食品工业(从粉丝、面制品、调味料及其他食品等方面)中的应用情况,以期为扩大甘薯淀粉资源的研究和应用提供参考。     

蔬菜鱼糊制品加工工艺研究

以罗非鱼肉和蔬菜为原料，开发一种适合咀嚼吞咽障碍人群食用的营养蔬菜鱼糊制品。以感官评分为评价指标，对鱼糊的加工工艺进行优化。结果表明，鱼糊的最佳加工工艺为低筋面粉添加量5%、冰添加量40%、蛋清添加量70%、色拉油添加量20%。在此基础上，添加鱼肉质量50%的蔬菜，制成5种营养蔬菜鱼糊。质构分析与感官评分表明，南瓜鱼糊和胡萝卜鱼糊的硬度、咀嚼性、胶着性、断裂性均较低，更适合咀嚼吞咽障碍人群食用。     

响应面法优化甘薯泥馒头加工工艺

以20%甘薯泥和小麦粉为原料,研究压面次数、醒发时间、醒发温度对甘薯泥馒头品质的影响规律。在单因素实验基础上,选取感官评价为考察指标,利用响应面分析法对甘薯泥馒头加工工艺进行优化。结果表明,甘薯泥馒头的最佳工艺为:压面次数14次,醒发时间18 min,醒发温度33℃。所制作的甘薯泥馒头品质较好,具有特殊的甘薯香味。     

甘薯全粉研究进展

甘薯全粉是近年新兴甘薯产品,我国甘薯资源丰富,较适合在我国进行规模生产。该文分析甘薯全粉概念,介绍甘薯全粉生产工艺、品质特性及在食品加工中应用,并展望我国甘薯全粉市场前景,指出发展甘薯全粉加工有利于推动我国甘薯产业良性发展。     

基于主成分分析和质构分析的甘薯泥品质综合评价

目的 利用主成分分析和综合评价建立方便、快捷的甘薯泥加工品质综合评价方法.方法 采用质构分析和多元统计学方法相结合,对7个甘薯泥的基本成分和质构品质进行了相关性和主成分分析,并进行综合评价.结果 不同品种甘薯泥的基本成分在淀粉含量和水分含量上都有显著差异(P<0.05).甘薯泥的基本成分、感官评分和质构品质指标间有部分...     

质构分析在肉制品检测中的应用

质地特性是衡量肉与肉制品食用品质的重要参数,对肉品加工、贮运及安全都具有重要意义。质构仪是一种客观、快速衡量食品质地特性的方法,此方法已在肉制品、米面制品、乳制品、糖果、果蔬等食品的物性学分析得到应用。本文介绍了质构仪检测的原理和方法,综述了目前国内外质构仪在肉与肉制品品质检测中的应用情况,包括仪器质地参数与感官质地参数之间的相关性、肉制品品质与鲜肉新鲜度的检测、加工和食用品质的判别,肉制品生产工艺的优化等的国内外研究现状。     

微波膨化甘薯鱼糜脆片的加工工艺优化

以甘薯泥和三文鱼加工副产物制作而成的鱼糜为主要加工原料,采用微波膨化技术制作甘薯鱼糜脆片,以产品的感官品质和质构特性为评价指标,通过单因素实验,研究微波膨化条件、植物油添加量、糯米粉添加量、小苏打与碳酸氢铵添加量及其添加比例对甘薯鱼糜脆片的品质影响,并通过正交试验确定最佳工艺。结果表明:以鱼糜与甘薯泥总质量为基准,添加植物油4%,糯米粉30%,小苏打和碳酸氢铵以2:1比例添加1.0%,在500 W功率下微波膨化120 s,制得的甘薯鱼糜脆片感官得分为(86.5±1.01)分,硬度值与脆度值分别为(7654.125±123.521) g、(8165.365±105.347) g,外观完整,色泽均匀,口感酥脆。     

新型天然色素——紫甘薯色素

紫甘薯色素作为一种新型天然色素,具有色泽鲜亮,无毒,无异味以及兼具多种营养、药理和保健功能等特点,适合现代人对健康、安全理念的要求。本文主要论述了紫甘薯色素结构特点、生物学特性及应用前景。     

国内外微波食品的概况及发展趋势

１国内外微波食品的概况微波食品是应用现代加工技术,对食品原料采用科学的配比和组合,预先加工成适合微波炉加热或调制,便于食用的食品。微波食品的加工技术是现代食品加工技术的组合,制造的食品及其包装需要有独特性,即适合微波炉加热。微波加热具有迅速、省时、经...     

Microbial growth and the effects of mild acidification and preservatives in refrigerated sweet potato puree

Refrigerated sweet potato puree is a convenient form of sweet potato that can be used as an ingredient in formulated foods. The microbiology of refrigerated sweet potato puree during storage for up to 5 weeks was evaluated. Because the puree was made by comminuting steam-cooked sweet potatoes before refrigeration, no naturally occurring vegetative bacterial cells were detected during a 4-week period of refrigerated storage at 4 degrees C. However, if postprocessing microbial contamination of the puree were to occur, contaminating microorganisms such as Listeria monocytogenes could grow during refrigerated storage. The effects of acidification or the addition of potassium sorbate and sodium benzoate on a population of L. monocytogenes inoculated into refrigerated (4 degrees C) sweet potato puree were determined. Inoculation of the refrigerated puree with L. monocytogenes at 10(6) CFU/ml resulted in a 3-log increase after 3 weeks storage of nonsupplemented puree. Supplementation of the sweet potato puree with 0.06% (wt/vol) sorbic acid or benzoic acid plus mild acidification of the sweet potato puree with citric acid to pH 4.2 prevented growth of L. monocytogenes during storage at 4 degrees C.     

Physicochemical and sensory properties of fresh potato-based pasta (gnocchi)

This study dealt with the characterization and quality assessment of 3 kinds of potato-based pasta (gnocchi) made with steam-cooked, potato puree (water added to potato flakes), and reconstituted potatoes as main ingredients. The aim of the research was to evaluate the quality of the products in terms of physicochemical, textural, and sensory characteristics. Water content, water activity, color (L* and h°), and texture (texture profile analysis [TPA] and shearing test) were evaluated on both raw and cooked samples. In addition, on the recovered cooking water the loss of solid substances was determined and on the cooked gnocchi a sensory assessment was performed. Eight sensory attributes (yellowness, hardness, gumminess, adhesiveness, potato taste, sweet taste, flour taste, and sapidity) were investigated. Statistically significant differences among products were obtained, especially concerning textural properties. In fact, sample made with reconstituted potatoes and emulsifiers resulted the hardest (8.53 ± 1.22 N), the gummiest (2.90 ± 0.05 N), and the "chewiest" (2.90 ± 0.58 N) after cooking. Gnocchi made with potato puree or reconstituted potatoes significantly differed from the one produced with steam-cooked potatoes in terms of sensory properties (yellowness, hardness, flour taste, and sapidity). Pearson's correlation analysis between some textural instrumental and sensory parameters showed significant correlation coefficients (0.532 < r < 0.810). Score plot of principal component analysis (PCA) confirmed obtained results from physicochemical and sensory analyses, in terms of high discriminant capacity of colorimetric and textural characteristics.     

Improved Aseptically Filled Sweet Potato Purees

A high quality sweet potato puree with better color stability than frozen purees was produced by flash sterilization followed by aseptic packaging. Starch conversion time was shortened by slicing the sweet potatoes and accurately controlling the temperature during conversion. Processing of inoculated purees for 13 sec at 138°C followed by aseptic filling was adequate for commercial stability. The effect of several processing variables on puree and sweet potato souffle quality was examined. Improved quality and storage stability of sweet potato purees were accomplished by flash sterilization at very high temperatures followed by aseptic packaging.     

添加剂对熟制甘薯抗老化作用的研究

为了抑制熟制甘薯在贮藏期间的老化,以优质甘薯为原料,经烘烤、熟刺、搅拌成泥,加入抗老化剂制成熟制甘薯食品,并进行冷冻储藏。研究了添加不同抗老化剂对熟制甘薯的保水力、糊化性质和老化程度的影响。结果表明,添加了抗老化剂的熟制甘薯保持了其特有的口感风味,且保水力较大,糊化特性和老化度都不同程度地优于不添加抗老化剂的熟制甘薯．     

Effects of combined radio frequency with hot water blanching on enzyme inactivation,color and texture of sweet potato

Sweet potato is an important food crop with rich nutritional value, and also a commonly used feed and industrial raw material. However, the quality of sweet potatoes may decline during storage and thermal processes because of enzymatic reaction induced by peroxidase (POD). Radio frequency (RF) blanching was thus proposed to reduce POD activities. Effects of electrode gaps and sample thicknesses on the RF heating rate and uniformity in sweet potato were studied. Influences of hot water blanching and combination of RF heating with hot water blanching on enzyme inactivation and physiochemical properties of sweet potatoes were also analyzed. Results showed that the optimum RF heating uniformity was obtained at an electrode gap of 90 mm and a sample thickness of 60 mm. Combined RF with hot water blanching effectively inactivated POD in sweet potatoes. Compared to hot water blanching, combined RF with hot water blanching gave better sample color, texture values, and lower weight loss when achieving the same level of enzyme inactivation (< 10%). Therefore, combined RF with hot water blanching is recommended as an effective, uniform and high-quality blanching technology for sweet potatoes.     

EFFECTS OF PUREE PROCESSING METHODS ON THE TEXTURAL CHARACTERISTICS OF AN ALGINATE- TEXTURIZED SWEET POTATO PRODUCT1

The objective was to determine the effect of sweet potato (SP) puree preparation methods on the properties of texturized SP products. The treatments were separated into two main types in which sliced SPs were cooked prior to puree preparation, or purees were prepared by grinding raw roots, followed by heat processing using steam injection. Purees from each treatment were texturized into cylinders 12.7 cm long and 5.5 cm in diameter, using an alginate-calcium system, and frozen. We found that cooked purees prepared by steam injection of raw purees had higher viscosities than did purees made from cooked SP. Texture Profile Analysis (TPA) revealed that texturized product made from SP cooked before puree preparation was the most fracturable and least springy of the texturized products. Sensory panelists did not express apreference for texturized product from any of the treatments, but 23% of the panelists noted a grainy texture and/or raw root aroma in products prepared by steam injection of raw purees. In view of these observations and the fact that puree preparation from cooked SP is the simplest process, this process appears to be the best for this type of texturized SP product.     

Evolution of the physicochemical properties of oil-free sweet potato chips during microwave vacuum drying

The demand for healthy and convenient foods is a worldwide trend. Sweet potato attracted great attention due to its carbohydrates with a low glycemic index. Dehydrated sweet potatoes can be an excellent alternative for using and adding value to this raw material. The objective of this study was to evaluate the physicochemical properties of sliced sweet potato during the microwave vacuum drying (MWVD) for producing crispy oil-free chips. Fresh sweet potato samples were selected, peeled, sliced, blanched, and then dehydrated using a microwave oven adapted with a vacuum chamber and a rotation system to operate under vacuum. It was measured the evolution of moisture, water activity, temperature, color, apparent specific mass, porosity, and acoustic/mechanical analysis of the texture during the MWVD. Crispy sweet potato chips were obtained in <30 min, presenting low moisture (0.028 g g⁻¹ db) and water activity (0.262). The dehydrated samples showed high porosity (67.5%) and a low apparent density (0.456 g cm⁻³). Optical micrographs and acoustic/mechanical properties showed an expanded (puffed) product structure with large pores, which resulted in irregular acoustic/mechanical signals, characteristics of a crispy food matrix. Colorimetric analyses indicated a little change between fresh and dried samples, with an absence of burnt spots. In conclusion, MWVD is a suitable process to produce highly porous sweet potato chips, adding value, and extending the vegetable's shelf life.     

Controlled Alpha Amylase Process for Improved Sweet Potato Puree

A process using a commercial alpha amylase was developed for producing consistent sweet potato puree independent of age or seasonal variations in the raw roots. The process includes thermal gelatinization of the puree starch, enzyme hydrolysis of a portion of the puree, and subsequent blending of the enzyme-treated portion with the untreated portion. Alcohol insoluble solids decreased as the percentage of enzyme-treated puree in the mixture was increased. Chemical and rheological differences comparing purees made from fresh and stored roots became insignificant when the proportion of enzyme-treated puree was greater than 75%. Sensory texture differences were insignificant if the proportion was greater than 50%.     

Texture Modification Technologies and Their Opportunities for the Production of Dysphagia Foods: A Review

Dysphagia or swallowing difficulty is a common morbidity experienced by those who have suffered a stroke or those undergone such treatments as head and neck surgeries. Dysphagic patients require special foods that are easier to swallow. Various technologies, including high‐pressure processing, high‐hydrodynamic pressure processing, pulsed electric field treatment, plasma processing, ultrasound‐assisted processing, and irradiation have been applied to modify food texture to make it more suitable for such patients. This review surveys the applications of these technologies for food texture modification of products made of meat, rice, starch, and carbohydrates, as well as fruits and vegetables. The review also attempts to categorize, via the use of such key characteristics as hardness and viscosity, texture‐modified foods into various dysphagia diet levels. Current and future trends of dysphagia food production, including the use of three‐dimensional food printing to reduce the design and fabrication time, to enhance the sensory characteristics, as well as to create visually attractive foods, are also mentioned.