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A series of sulfate-based Gemini anionic surfactants were synthesized via etherification, ring opening and sulfation reactions using epichlorohydrin, fatty alcohol, ethylene glycol and chlorosulfonic acid as the main raw materials. Orthogonal experiments for 1,8-bisalkoxymethylene-3,6-dioxin-1,8-octane disulfate were performed on the sulfation reaction to determine the optimal reaction conditions.

A series of sulfate-based Gemini anionic surfactants were synthesized via etherification, ring opening and sulfation reactions using epichlorohydrin, fatty alcohol, ethylene glycol and chlorosulfonic acid as the main raw materials. Orthogonal experiments for 1,8-bisalkoxymethylene-3,6-dioxin-1,8-octane disulfate were performed on the sulfation reaction to determine the optimal reaction conditions. The structures of the intermediate and final products were characterized by FT-IR (Fourier transform infrared spectroscopy analysis), ¹H-NMR (proton nuclear magnetic resonance spectroscopy) methods. The thermal performance of surfactants was analyzed using thermogravimetric analysis (TGA). The thermogravimetric results showed that the sulfate-based Gemini surfactants had good heat resistance (the thermal decomposition temperature of which was in the range of 140∼170?). The Krafft point, surface tension, foaming, Hydrophile–Lipophile Balance Number (HLB), emulsifying, wetting, and lime-soap dispersing performance were measured by visual observation, hanging drop method, aqueous surfactant solution method and Borghetti–Bergman method, respectively. The results have shown that all the sulfate-based Gemini surfactants had good water solubility and lime-soap dispersing ability. When spacer group was -(CH2)2-, with the increase of the carbon chain length from C12 to C14, the micellar concentration critical micelle concentration and surface tension (CMC) gradually increased from 8.25 × 10^–4 mol/L to 8.75 × 10^–4 mol/L and 27.5 mN/m to 30.9 mN/m, respectively. Also, the sulfate-based Gemini surfactants with the different length of the spacer group had a different effect on their performance on foaming properties and foam properties, HLB and emulsifying ability and wetting ability.

In view of the important role of the spacer group and the general use of anionic surfactants in oil fields, this article considers the preparation of a series of sulfate-based Gemini surfactants by changing the spacer group and the chain length of the hydrophobic group and evaluating their surface activity, and finally its Kraffi, on the foam properties, HLB value, emulsifying performance, lime soap dispersing ability etc.

Sulfate-based Gemini surfactants have broad application prospects in the fields of oil and gas exploitation, environmental protection, chemistry and daily chemical industry and so on.

A novel two series of self‐sequestering surfactants have been prepared by the reaction of itaconic acid, phthalic anhydride, citric acid with oxypropylated 1,4‐butane diol and oxypropylated 1,6‐hexane diol. The structure features of these surfactants have been confirmed by IR and ¹H NMR spectra. These surfactants exhibit excellent properties of self‐sequestering. Besides good surface active properties including surface tension, interfacial tension, low foaming, good wetting properties, good stability towards acidic and basic media, emulsifying power and dispresent properties, solubilization properties and good biodegradability, they possess autonomous sequestering ability without any help of additional sequestering agent.

At present, the conventional method of preparing cationic fluorinated acrylic latex is to emulsify copolymerised monomers with cationic surfactants. However, there has been a wide concern about using Gemini surfactants to prepare cationic polymer latex to improve its properties. The purpose of this paper was to focus on the synthesis of novel self-crosslinked cationic fluorinated acrylic latex (SCFAL), during which the copolymerised monomers were initiated with a water soluble azo initiator and emulsified with mixed surfactants of Gemini emulsifier and alkyl polyglycoside (APG).

The novel SCFAL was prepared successfully by the semi-continuous seeded emulsion polymerisation of butyl acrylate, methyl methacrylate, hexafluorobutyl methacrylate (HFMA) and hydroxy propyl methacrylate (HPMA) in aqueous medium.

The conversion is the maximum and the coagulation percentage the minimum when the amounts of emulsifier and initiator are 8 and 0.6 per cent, respectively. The average particle size of the latex is significantly reduced with the increase of the amount of emulsifiers used. However, the average particle size of the latex is increased with the increase of the amount of HPMA. The particle size of the latex is of a unimodal distribution, which means that the particle size was reasonably uniform. Contact angle is increased with the increase of the amount of the HFMA.

The novel SCFAL can be widely used as significant components in the field of coatings, leather, textile, paper, adhesives and so on.

SCFAL, which was emulsified with novel mixed surfactants of Gemini surfactant and APG, has been prepared successfully. Influences of amount of initiator, emulsifier, HPMA and HFMA on emulsion polymerisation and/or properties of novel latex are investigated in detail.

This paper aims to investigate the physical, chemical and physicochemical characteristics of rice husk on alkaline treatment.

Rice husk (RM) was alkaline treated to produce soluble (SR) and insoluble residues (IR). Each fraction was characterized and soluble fraction was used to produce nanofibres using electrospinning method.

Alkaline treatment was effective in isolating insoluble dietary fibre rich IR from the other interfering substances such as soluble dietary fibre, protein and lipids that originally present in RM and leached into SR. The problem of silica induced toxicity and indigestibility of rice husk was overcome by alkaline treatment. Alkaline treatment altered the inherent mineral content (calcium, copper, iron, potassium, magnesium, manganese, sodium, phosphorus, zinc) of rice husk, and increased physicochemical properties such as emulsification ability and stability, water holding ability, mineral binding capacity (calcium, copper, iron, zinc), and antioxidant activity. SR had been successfully electrospun into nanofibres with the addition of polyvinyl alcohol.

The paper investigated the characteristic of rice husk (RM and IR) for the development of functional foods, pharmaceutical products and new bioactives delivery system at the expense of reducing environmental liability.

The purpose of this paper is to study the utilization of the rice bran protein concentrate (RBPC) in biscuits to upgrade the nutritional quality.

Extraction of rice bran protein concentrate (RBPC) from defatted rice bran was standardized using alkali extraction method. Defatted rice bran and RBPC were analyzed for their proximate composition. RBPC was analyzed for its bulk density, foaming capacity (FC), emulsion activity (EA), and water and oil absorption capacity. RBPC was incorporated in biscuits at 5, 10 and 15 per cent levels. The biscuits were analyzed for their physicochemical, fracture strength (texture analyzer) and sensory attributes (nine‐point hedonic scale) to assess their acceptability.

The maximum yield of 13.2 per cent for RBPC was obtained at alkaline pH of 11, temperature of 60°C and extraction time of 60 minutes. The bulk density, foaming capacity, emulsifying ability, water and oil absorption capacity of RBPC were 0.4 g/ml, 11 per cent, 40 per cent, 2.9 ml/g and 2.3 ml/g respectively. The protein content of biscuits increased significantly from 7.3 per cent in control biscuits to 15.4 per cent in the 15 per cent RBPC supplemented biscuits with their fracture strength also significantly higher than the control biscuits (p<0.05). Replacement of refined wheat flour up to 10 per cent RBPC produced protein‐enriched biscuits with desirable overall acceptability.

Rice bran protein concentrate can be beneficially utilized to formulate protein enriched biscuits with enhanced nutritional value especially for malnourished or undernourished people.

This review provides an overview of the applications of Bambara groundnuts in various food products. The genetic diversity, physical properties and chemical compositions of the crop are also elucidated.

This paper critically reviewed the physicochemical properties and applications of Bambara groundnuts from recent literature.

Bambara groundnut (Vigna subterranea) is a drought-tolerant crop from West Africa that contains not only carbohydrates and fats but is also high in protein. The cultivars of Bambara groundnut can be distinguished by the colours of seeds, which range from red, blue-eye, brown and black-eye. Bambara groundnuts contain carbohydrate (57–67%), protein (15–25%), fat (4–8%), fibre (1.4–1.5%) and ash (2.9–4%). As a percentage of protein, the essential amino acids, lysine, methionine and cysteine are relatively high in Bambara groundnuts. Meanwhile, linoleic, palmitic and linolenic acids are the fatty acids present in this crop.

Several studies have shown that Bambara groundnuts can be used as fat substitutes, emulsifiers, water binders, bulking agents and thickeners due to its water and oil absorption properties, gelling, pasting, emulsifying and foaming abilities. Bambara groundnuts are used in the development of many intermediate or final products like flour blend, cookies, bread and fermented milk. It has a positive impact on the overall proximate, functional, mineral and amino acid profiles of the food products.

Despite its high nutrient density, Bambara groundnuts are an underutilised legume due to unavailability and lack of knowledge among consumers on its benefits. There is a need to promote the use of Bambara groundnuts as a future food.

Some months ago a national organisation established to keep a watchful eye on the Nation's diet expressed concern over the eating trends of people in what to them appeared to be developing inbalances of necessary nutrient factors and the inadeuacy not so much of calories and energy values but in the nature and quality of main food factors. It was recommended that the national diet should be improved, but the authorities pointed to the National Food Survey results to show that the diet was not deficient; that the average daily intake of protein, vitamins, minerals and overall energy requirements were satisfied; all of which is true for the not‐too‐generous levels set. Even the pensioner households included in the Survey sample appear well‐fed. What causes concern is the year‐by‐year decrease in staple foods consumed—milk, red meat, bread, fresh vegetables—and the heavy reliance on refined, processed foods. In its annual reports on NFS reviews, the BFJ has almost monotonously referred to this downward trend. Individual NFS Reports do not reveal any serious deficiencies, as yet, but in the trend over the years—and herein lies the real value of the Survey and its data—few if any of the changes have been for the better; movements in food groups have tended to be downwards. If these trends continue, the time must surely come when there will be real deficiencies; that substitution within a food group cannot make good essential foods severely rationed by high prices.

Surface active agents are widely used to impart special characteristics to surface coatings formulations. The large variety of “surfactants” now commercially available may leave the coating technologist with the problem of how to choose the best for his particular system. It is hoped that by outlining the relationships between molecular structure and surfactant properties a reasonable working basis for selection of surfactants may be gained.

This paper aims to evaluate the effects of salting duration and salt concentration on the physicochemical, colour, texture and sensory attributes of buffalo meatballs.

Minced buffalo meat was mixed with salt at 1 or 2% concentration and stored for 0 h, 24 h or 48 h during the preparation of meatballs. The developed meatballs were analysed for moisture content, water holding capacity (WHC), pH, cooking yield, shrinkage, colour, texture profile analysis, gelling properties and sensory attributes.

The salting durations of 24 and 48 h had significant (p < 0.05) effects on the WHC and colour attributes of the buffalo meatballs. A 2% salt addition in meatballs significantly (p < 0.05) affected pH and cooking yield. Salting for 24 h with 2% salt concentration significantly (p < 0.05) increased the hardness, chewiness and gel strength of the meatballs. Thus, salting for 24 h with a 2% salt concentration improved the physicochemical, textural and sensory attributes of buffalo meatballs.

The study highlighted the importance of salting treatment during the preparation of meat products. For example, salting buffalo meatballs with a 2% salt concentration for 24 h could improve their functional and sensory attributes.

Studies on salting durations at different salt concentrations in buffalo meat are very limited. An optimized combination of salting duration and salt concentration during the preparation of buffalo meatballs could improve the quality attributes and acceptability of these products.

SOME four or five years ago, the Wright Air Development Centre, Wright‐Patterson Air Force Base, Ohio, began to receive an increasing number of complaints of corrosion of wheel bearings on both operational aircraft and aeroplanes which had been inactive for extended periods. Many instances of wheel bearing corrosion were also reported by the U.S. Navy, mostly on stored aircraft. The greases in question were those meeting Specification AN‐G‐15.