Encapsulation of food ingredients

Microencapsulation is a relatively new technology that is used for protection, stabilization, and slow release of food ingredients. The encapsulating or wall materials used generally consist of starch, starch derivatives, proteins, gums, lipids, or any combination of them. Methods of encapsulation of food ingredients include spraydrying, freeze‐drying, fluidized bed‐coating, extrusion, cocrystallization, molecular inclusion, and coacervation. This paper reviews techniques for preparation of microencapsulated food ingredients and choices of coating material. Characterization of microcapsules, mechanisms of controlled release, and efficiency of protection/ stabilization of encapsulated food ingredients are also presented.     

Applications of emerging imaging techniques for meat quality and safety detection and evaluation: A review

With improvement in people's living standards, many people nowadays pay more attention to quality and safety of meat. However, traditional methods for meat quality and safety detection and evaluation, such as manual inspection, mechanical methods, and chemical methods, are tedious, time-consuming, and destructive, which cannot meet the requirements of modern meat industry. Therefore, seeking out rapid, non-destructive, and accurate inspection techniques is important for the meat industry. In recent years, a number of novel and noninvasive imaging techniques, such as optical imaging, ultrasound imaging, tomographic imaging, thermal imaging, and odor imaging, have emerged and shown great potential in quality and safety assessment. In this paper, a detailed overview of advanced applications of these emerging imaging techniques for quality and safety assessment of different types of meat (pork, beef, lamb, chicken, and fish) is presented. In addition, advantages and disadvantages of each imaging technique are also summarized. Finally, future trends for these emerging imaging techniques are discussed, including integration of multiple imaging techniques, cost reduction, and developing powerful image-processing algorithms.     

阴香果实主要成分分析

以烘干法、蒽酮比色法、凯氏定氮法、索氏浸提法、盐析法、比色法和正丁醇- 盐酸法分别测定阴香果实的含水量、总糖、蛋白质、粗脂肪、果胶、花色苷和原花青素的含量。结果表明：阴香果实鲜果含水量为52.29%,果肉、果核的含水量分别为64.69%、30.99%;果肉、果核占鲜果质量百分比分别为64.06%、35.88%;干果果肉总糖、蛋白质、脂肪、果胶、原花青素、花色苷的含量分别为19.08%、5.49%、23.91%、1.16%、1.27% 和1.62%;干重果核总糖、蛋白质、脂肪、果胶和原花青素的含量分别为5.12%、9.27%、61.15%、10.46% 及3.47%,果核中不含花色苷。研究表明,阴香果实中富含天然活性产物等多种可开发利用的成分,综合开发利用价值大。     

古贝春酒中的呈香呈味物质GC-MS分析研究

利用闻香,结合气相色谱-质谱仪分析方法对古贝春白酒中的各种香味成分进行定性和定量分析。结果表明,定性、定量出70多种风味化合物,包括25种酯类、13种酸类、10种醇类、5种醛类、1种酮类、10种芳香族及酚类、5种呋喃类、2种吡嗪类、2种缩醛类物质和1种硫化物。(晓文)     

大黄的降血脂生物活性成分及作用机制研究进展

大黄 (Rheum) 是蓼科 (Polygonaceae) 多年生草本植物，是我国医药学领域应用最广泛的草药之一。越来越多的研究表明大黄中的蒽醌类、蒽酮类、芪类、糖类、鞣质类、黄酮类和苯丁酮苷类等可能是预防或治疗高脂血症及其并发症的有效生物活性成分。本文综述了大黄中主要化合物及其降血脂作用的机制，主要从实验模型、剂量、作用和机制以及基本结构等对各种活性成分进行系统阐述。大黄中的主要降血脂生物活性成分可以分为蒽醌类、芪类、多糖和其他类等4类，这些成分集中在抑制外源性脂类吸收、抑制内源性脂类合成、调控脂质的转运和代谢以及调节肠道菌群等方面上发挥降血脂作用，主要涉及AMPK、PPARs、CYP7A1、SREBP、LDLR、ABCA1、PCSK9、NPC1L1等重要的降血脂作用靶点。本综述将为大黄的降血脂生物活性研究提供新的思路、借鉴与方法，为开发安全、有效的降血脂功能性产品提供一定的理论基础和科学依据。     

Evaluation of mycotoxin-contaminated cereals for their use in animal feeds in Hungary

In the period between December 5, 1991 and September 17, 1998, 760 maize, 367 wheat, 119 soybean, 222 barley, 85 bran, 32 triticale, 60 oat, 14 rye and 22 sunflower samples were investigated for the presence and concentration of seven fusariotoxins (T-2 toxin, zearalenone, deoxynivalenol, nivalenol, diacetoxyscirpenol, HT-2 toxin, fusarenone-X) and OTA. The comparison of analytical data with those of the relevant literature revealed that although the incidence rate and/ or concentration of Fusarium mycotoxins and OTA in Hungarian-grown cereals is occasionally considerable, the position of the country is not worse than the average of countries. Our findings indicate that soybean tends to be good substrate for trichothecene-producing fungi and the rate of contamination is regarded as substantial. The commodities were assorted into one of three quality categories. The proportion of objectionable samples was only 3.0, 2.2, 2.3 and 1.7% in maize, wheat, barley and soybean samples, respectively. However, this low rate of objection might still be a source of great economic loss. The proportion of objectionable samples was much higher in the case of bran, oat and triticale (7.1, 6.7, and 6.3%, respectively). The results of the present investigation indicate a need for regular screening for mycotoxins of importance and individual appraisal of each commodity from the point of their use in animal feeds.     

Microbiology of food taints

Fresh and processed foods are often spoilt by the presence of undesirable flavours and odours caused by microbial action. The aim of this paper is to review the current knowledge of microbiologically induced taints that occur in a wide range of foodstuffs, including meats, poultry, fish, crustaceans, milk, dairy products, fruits, vegetables, cereals and cereal products. Examples have been chosen where the compounds responsible for the taint have been identified and sufficient data obtained to demonstrate the involvement of microorganisms. However, in some cases the full identity of the causative organism may not have been elucidated. The types of microorganisms covered by this review include bacteria, fungi, yeasts, actinomycetes and cyanobacteria. Although cyanobacteria do not in general infect foods, their presence in aqueous systems and water supplies can lead to off-flavours in aquatic organisms and processed foodstuffs. Several examples of each of these processes are discussed. Wherever possible, the likely biosynthetic pathway used by the microorganism to produce the offending compound in a foodstuff is indicated.     

Novel quality control methods in conjunction with chemometrics (multivariate analysis) for detecting honey authenticity

The importance of honey has been recently upgraded because of its nutrient and therapeutic effect. The adulteration of honey increased exponentially in terms of both geographic and/or botanical origin. Therefore, the need has arisen for more effective quality control methods aiming at detecting adulteration. Various novel, fast, and accurate methods like AAS, HPLC, GC-MS, ES-MS, TLC, HPAED-PAD, NMR, FT-Raman, and NIR have enriched the arsenal of analytical chemist in this direction. However, apart from these novel methods, the application of multivariate analysis and, in particular, PCA, CLA, and CA, proved to be extremely useful for grouping and detecting honey of various origins. Mineral and trace element analysis were repeatedly shown to be a very effective means for the classification purposes of honey of various origins (geographical and botanical).     

采前喷施壳聚糖复合膜对猕猴桃软腐病的防控及其保鲜作用

以‘贵长’猕猴桃为试材,通过病原菌分离、致病性测定和DNA测序鉴定了修文县猕猴桃软腐病病原菌,并选用壳聚糖、钙盐和糊精分别与茶多酚、甘氨酸、柠檬酸、抗菌肽混合制备和筛选了复合膜剂,研究了采前幼果期和壮果末期果面喷施壳聚糖复合膜对猕猴桃软腐病的防控及其保鲜作用。结果表明,修文县猕猴桃软腐病病原菌为葡萄座腔菌（Botryosphaeria dothidea）和拟茎点霉菌（Phomopsis sp.）;采前喷施不同壳聚糖复合膜对其软腐病的防效均达60%以上（添加茶多酚防效86.54%、甘氨酸防效61.54%、柠檬酸防效71.15%、抗菌肽防效69.23%）,显著降低丙二醛（MDA）积累,提高果实的超氧化物歧化酶（SOD）、过氧化氢酶（CAT）和过氧化物酶（POD）活性,诱导增强果实的抗病性。同时,该复合膜能有效地增加果实单果质量和体积,显著提高果实VC、可溶性固形物、可溶性总糖、可滴定酸、叶绿素和蛋白质的含量,促进猕猴桃产量的增加和品质的改善。此外,施用该复合膜还能有效提高和维持果实硬度、降低果实呼吸强度以及果实质量损失率和营养物质的损失,明显抑制果实可溶性固形物和可溶性总糖含量的上升速率和延缓组织的衰老软化,从而提高了猕猴桃耐贮性。研究结果为猕猴桃优质栽培、病害有机防控和果实绿色保鲜提供了科学依据和新途径。