Puffing Effects on Functional Properties of Amaranthus paniculatas (Rajgeera) Seed Flour

Among functional properties studied, water- anf fat-holding capacities were higher for puffed grain flour. Gelation was not affected, while foaming was adversely affected by puffing. A decrease in viscosity of flour pastes also resulted due to puffing.     

Structure and morphology studies of chromium film at elevated temperature in hypersonic environment

This paper presents the after shock heated structural and morphological studies of chromium film coated on hypersonic test model as a passive drag reduction element. The structural changes and the composition of phases of chromium due to shock heating (2850?K) are characterized using X-ray diffraction studies. Surface morphology changes of chromium coating have been studied using scanning electron microscopy (SEM) before and after shock heating. Significant amount of chromium ablation and sublimation from the model surface is noticed from SEM micrographs. Traces of randomly oriented chromium oxides formed along the coated surface confirm surface reaction of chromium with oxygen present behind the shock. Large traces of amorphous chromium oxide phases are also observed.     

INFLUENCE OF WATER ACTIVITY, pH, HEAT TREATMENT AND PRESERVATIVE ON CHEMICAL CHANGES IN CANNED INDIAN COTTAGE CHEESE (PANEER) DURING STORAGE

ABSTRACT

Influence of water activity (A_w), pH and heat treatment on the chemical changes such as Maillard browning, oxidation and lipolysis in canned paneer has been studied by response surface methodology. Browning in canned paneer in terms of hydroxymethylfurfural content increased during storage; however, it was pH dependent. At pH above 5.0, the rate of browning decreased as A_w increased from 0.90 to 0.98. At pH below 5.0, the rate increased with increased A_w from 0.90 to 0.98. Maximum browning rates were observed at pH 5.2–5.6, low A_w values (0.90–0.92) and high heat treatment levels (up to F value 0.8). At all pH levels, increased A_w increased the oxidation rate, more so at low pH levels. Up to an F value of 0.3, heat treatment seemed to have aided the oxidation rate, but higher F values retarded the oxidation rate, more so at low A_w. Lipolysis occurred during storage, but pH had little effect on the rate of lipolysis. High A_w supported high lipolysis rates.

PRACTICAL APPLICATIONS

Raw paneer (Indian cottage cheese), popular with people in Indian subcontinent and with Indian diasporas scattered in several countries, has a shelf life of less than a day at ambient temperatures. Several attempts are being made by workers to improve the shelf life of paneer by canning process so that its market within the country and abroad improves. However, canning at usual canning time–temperatures is leading to intense chemical changes in paneer, which is not being accepted by consumers. Authors have tried to obviate such unacceptable chemical changes by reducing the intensity of canning process by adjusting so called “hurdles” of the product by hurdle technology. The present paper is a part of that attempt describing the chemical changes in paneer subjected to low heat intensity canning process with altered “hurdles.” Because the chemical changes occurring in a food product are a function of various parameters called “hurdles” like pH, water activity, heat treatment, etc., the present work attempted to identify the combination of the “hurdles” at which chemical changes are the slowest, which may find better acceptance with consumers.     

An approach to the detection of synthetic milk in dairy milk: 1. Detection of urea

A qualitative test for the detection of externally added urea (as synthetic milk) was developed using soybean urease. The quantitative detection of synthetic milk in dairy milk could be achieved by this method based on the 'a' value of 'L, a, b' scale of the HunterLab colorimeter and also by the diacetyl complexation method. Both methods are sensitive enough to detect amounts as low as 2% synthetic milk added to dairy milk, corresponding to 20 mg of added urea per 100 ml.
This work reports on methods to detect and estimate unionic detergents, which are important ingredients of synthetic milk formulations, based on the extraction of a detergent—Methylcne Blue complex in chloroform which can be subsequently quantified by measuring the optical density at 653 nm. A base value of 0.52 for optical density was found to represent pure cow's milk Any result above this value suggested the presence of an anionic detergeni in milk.     

Carboxymethyl cellulose (CMC) as an additive for oil reduction in deep-fat fried paneer

The effect of different levels of CMC on the uptake of vegetable oil during the deep-fat frying of paneer was studied by: (i) direct addition of CMC to the milk and (ii) dipping the paneer cubes into solutions of CMC for different time intervals. The fried paneers were evaluated for chemical composition, hardness and sensory characteristics. Method (i) proved to be beneficial in all respects as compared to (ii), as the absorption of water from the suspensions of CMC destroyed the texture of the paneer.     

Parametric and mechanical characterization of linear low density polyethylene (LLDPE) using rotational moulding technology

In this research work, extensive literature review of the rotational moulding process using linear low density polythene (LLDPE) has been carried out to summarize the present status of the characterization in order to maintain quality and reliability of the products. The present characterization of rotomoulded products using LLDPE is based on the mechanical properties which are being altered by changing process parameters. However, it is observed that in the majority of applications of the products made of LLDPE using rotational moulding technology are prone to cracking failure due to manufacturing defects at room temperature. Therefore, study of fracture characterization of the material is equally important in relation to quality and reliability. In this article, the present characterization of the rotational moulded products using different polymers is summarized in the form of review and the importance of evaluation of the fracture behaviour of rotomoulded products is emphasized.     

Synthesis and study of organically capped ultra small clusters of cadmium sulphide

Ultra small clusters of cadmium sulphide are synthesized using non-aqueous and aqueous chemical methods. Thiophenol has been used as a capping agent for non-aqueous synthesis whereas various reagents such as mercaptoethanol, hexametaphosphate, ethylene glycol and ethanol have been used as additives for an aqueous method of synthesis. Properties of the clusters synthesized are discussed based on optical absorption, X-ray diffraction, transmission electron diffraction and photoelectron spectroscopy. Particles as small as 0.7 nm diameter could be synthesized with thiophenol and mercaptoethanol as additives. The effect of varying the molarities of the different additives on the properties of the CdS nanoclusters synthesized are discussed. Systematic ageing studies of the nanoclusters showed that larger particles age faster than the smaller clusters. Ageing also leads to better crystallization of the particles. It has been observed that the smallest particles (0.7 nm diameter) possess tetrahedrally bonded fragments of CdS and intercluster structural long range order does not exist. However, bigger particles (2.0 nm diameter) show bulk cubic structure. X-ray photoelectron spectroscopy studies have been done to study the purity and stoichiometry of the clusters synthesized and strongly support the existing proposal of the formation and stability of CdS nanoclusters.