Bovidae-based gelatin: Extractions method,physicochemical and functional properties,applications, and future trends

Gelatin is one of the most important multifunctional biopolymers and is widely used as an essential ingredient in food, pharmaceutical, and cosmetics. Porcine gelatin is regarded as the leading source of gelatin globally then followed by bovine gelatin. Porcine sources are favored over other sources since they are less expensive. However, porcine gelatin is religiously prohibited to be consumed by Muslims and the Jewish community. It is predicted that the global demand for gelatin will increase significantly in the future. Therefore, a sustainable source of gelatin with efficient production and free of disease transmission must be developed. The highest quality of Bovidae-based gelatin (BG) was acquired through alkaline pretreatment, which displayed excellent physicochemical and rheological properties. The utilization of mammalian- and plant-based enzyme significantly increased the gelatin yield. The emulsifying and foaming properties of BG also showed good stability when incorporated into food and pharmaceutical products. Manipulation of extraction conditions has enabled the development of custom-made gelatin with desired properties. This review highlighted the various modifications of extraction and processing methods to improve the physicochemical and functional properties of Bovidae-based gelatin. An in-depth analysis of the crucial stage of collagen breakdown is also discussed, which involved acid, alkaline, and enzyme pretreatment, respectively. In addition, the unique characteristics and primary qualities of BG including protein content, amphoteric property, gel strength, emulsifying and viscosity properties, and foaming ability were presented. Finally, the applications and prospects of BG as the preferred gelatin source globally were outlined.     

Screening of frozen-thawed conditions for keeping nutritive compositions and physicochemical characteristics of goat milk

Frozen milk can help producers overcome the seasonality of goat milk production, low goat production and short lactation periods, and avoid discarding milk during some special periods. We investigated effects of combination between freezing (cryogenic refrigerator of ?16 to ?20°C or ultra-cryogenic refrigerator of ?76 to ?80°C) and thawing (homeothermy of 20 to 25°C or refrigeration of 2 to 4°C) on nutritive compositions and physicochemical characteristics of raw goat milk during storage period (80 d). Compared with fresh goat milk, the frozen-thawed milk decreased contents of fat, protein, and lactose, as well as surface tension and stability coefficient, whereas increased effective diameter and polydispersity index. The average values of color values (L*, a*, and b*) in 4 group samples changed from 83.01 to 82.25, ?1.40 to ?1.54, 3.51 to 3.81, respectively, and the ΔE of most samples did not exceed 2. In contrast to the other 3 frozen-thawed treatments, goat milk treated with ultra-cryogenic freezing-homeothermic thawing (UFHT) possessed higher fat (5.20 g/100 g), smaller effective particle diameter (0.32 µm), and the lowest polydispersity index value (0.26). The color and confocal laser scanning microscopy images of UFHT were similar to those of fresh goat milk, illustrating UFHT was the optimal approach to maintain the natural quality of goat milk. Our finding provides a theoretical basis for producers to freeze surplus milk.     

Changes in the physical properties of honey powder during storage

Honey powders produced by spray drying with the addition of Arabic gum and sodium caseinate were characterised in terms of the influence of storage time on the following physical properties: particle size, moisture content, water activity, bulk density, flowability and hygroscopicity. The storage affected those properties; after 12 weeks of storage, particle size decreased (except Arabic gum powder treated as a control sample), moisture content and water activity increased, hygroscopicity decreased. Changes in bulk density, particle size and moisture content caused the rise of Hausner ratio value; however, the powders were still characterised by a very good flow properties and low cohesiveness. The colour of reconstituted powders was also affected by storage; in most of samples, the darkening, reduction in redness and yellowness were observed. Colour parameters were the most stable in powders obtained with the addition of 2% w/w of sodium caseinate.     

FCC原料掺入裂解焦油的研究及其机理分析

在催化裂化固定流化床小试装置上，对裂化原料中掺入富含芳烃的添加剂－裂解焦油进行了考察，确定了添加剂的最佳掺入量为1％，与不掺添加剂的裂化原料相比，其汽油产率提高，生焦量和干气产率减少，汽油选择性变好。同时通过对添加剂的原料体系的结构研究，对添加剂影响催化裂化过程的机理进行了探讨。     

康山金矿地质地球化学特征及其成因

康山金矿产在豫西熊耳山古隆起区的结晶基底太华群和盖层中元古界熊耳群地层接触界面附近，矿体严格受构造破碎蚀变带控制。流体包裹体，稳定同位素等研究表明，成矿物质来自太华群变质岩，成矿流体的性质与变质热液截然不同，而与花岗岩浆热液相近似。该矿床的形成与燕山期发生的同构造－花岗岩浆期热液活动有关，金沉淀成矿阶段有大气水的混入。     

Physicochemical and Sensory Properties of Soymilk-incorporated Bulgur

ABSTRACT Bulgur cooked in soymilk of 6% and 9% solid content had significantly ( P < 0.05) higher bulk density compared with bulgur cooked in soymilk of 3% solid content and control bulgur cooked in water. As the soymilk solid content increased, pilav bulgur yield increased whereas fine bulgur yield decreased. The SDS-extractability of bulgur proteins increases with the increase in soymilk solid content. Water absorption capacity of fine bulgur samples was affected by soymilk incorporation, and variations in oil absorption capacity were not significant ( P > 0.05). Soymilk incorporation improved color and sensory properties of pilav and fine bulgur. The results of this study suggest that soymilk can be successfully applied to bulgur production.     

1-环丙基-7-氯-6-(1-哌嗪基)-4-氧-1,4-二氢-3-喹啉羧酸盐酸盐的熔化与离解性质研究

1－环丙基－7－氯－6－（1－哌嗪基）－4－氧－1，4－二氢－3－喹啉羧酸盐酸盐为环丙沙星合成中主要的杂质之一，研究其物化性质对于改善环丙沙星的结晶分离提纯具有重要意义。本文研究了1－环丙基－7－氯－6－（1－哌嗪基）－4－氧－1，4－二氢－3－喹啉羧酸盐酸盐的熔化，分解特性，溶解度与离子强度，温度和pH值的关系，并测定了该物质的离解常数，估算了该物质在水溶液中的活度积。