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Behavior of mode I crack tip in fiber metal laminate (FML) differs from that in homogeneous or plain specimen made of metal used in the laminate due to the load transfer effect in the laminate caused by property mismatch between dissimilar material layers. The purpose of this paper is to present a finite element investigation on the characteristics of crack tip in monotonically loaded and residually stressed FML.

Crack tip characteristics are assessed by: the sizes of various zones that form at the tip; and crack tip energy release rates. The same are found by modeling two types of Glare laminates under monotonic tension with different crack orientations in SSY regime – Type I and Type II. Residual stresses are externally introduced in the models. Delaminations are modeled by cohesive elements. Crack tip zone sizes are measured from finite element solutions. Values of J integrals are computed over cyclic paths near the crack tips. Identically cracked and loaded plain aluminum alloy specimens are also modeled for comparison.

The sizes of crack tip zones in Glare laminates are found to be different than those in plain specimens. Process zone is observed to form at crack tip in Type I laminate whereas it does not develop in Type II laminate, the reverse being true in plain specimens. Values of J integrals near crack tips are also found to deviate from those in plain specimens, higher in Type I laminate due to crack tip stress amplification and lower in Type II laminate due to stress reduction. Crack orientation decides the amplification or shielding effect in the laminate.

There is scope for validating the numerical results reported in the paper by theoretical models.

The method to quantify crack tip shielding and amplification is presented that shall be useful in checking the structural integrity/safety of the laminate during actual service conditions.

Shielding and amplification effects are explicitly described and illustrated in the paper. Suitability of using J integrals over paths crossing non-homogeneous and property mismatched material layers is tested. Use of cohesive zone method that is readily applicable in finite element procedures and is relatively simple, fast and reasonably accurate is also demonstrated.

There have been plans to merge UCO Bank with larger banks owing to its poor performance for many years. There were leaders in the history who had not been committed. The inadequate governance of the bank has been responsible for some of the major lapses. Mr. Arun Kaul took strategic initiatives and systematically strengthened the functioning of the board. It enabled the bank to turnaround and report profits in challenging economic conditions. The Bank is not yet completely safe and probably need strengthening of its competencies to emerging challenges.

Since failure of laminated composites by delaminations is common, the purpose of this paper is to present a numerical procedure to check the stability of delaminations in fiber metal laminate (Glare), with different possible damage configurations, under uni-axial tension. Deformation behavior of the laminate is also examined. Influence of the type and the extent of damage, represented by varying sizes and number of delaminations, on delamination driving force and laminate deformation is found.

Delaminated Glare is modeled by finite element method. Interface cohesive elements are used to model the delaminations. Finite element results provide the deflection/deformation characteristics of the laminate. Driving forces of delaminations are estimated by J integrals that are numerically obtained over cyclic paths near delamination tips. Laminates with different types of delaminations are also fabricated and externally delaminated for measurement of their interlaminar fracture toughness. The delamination is considered to be stable if its driving force is less than corresponding interlaminar fracture toughness of the laminate.

Delaminations are found to be stable in laminates with lower number of delaminations and unstable in laminates with higher number of delaminations. Increase in size of delaminations increases the deformations but reduces the delamination driving force whereas increase in number of delaminations increases both deformations and driving forces. The trends change in case of laminates with symmetrical damage. Shape of delamination is also found to influence the deformations and driving forces. The finite element model is validated.

There is scope for validating the numerical results reported in the paper by theoretical models.

Checking the stability of delaminations and their effect on deformation behavior of the laminate helps is assessment of safety and remaining life of the laminate. If failure is predicted, preemptive action is taken by using repair patch ups at identified critical locations in order to avoid failures in service conditions.

The paper offers the following benefits: use of cohesive zone method that is readily possible in finite element procedures and is relatively simple, fast and reasonably accurate is demonstrated; suitability of using J integrals over paths crossing non-homogeneous and property mismatched material layers is tested; and influence of the type and the extent of damage in the laminate on its deformation behavior and delamination driving forces is found. This type of work has not been reported so far.

This paper aims to explore the possibility of utilization of Asparagus racemosus as a novel natural preservative in meat products.

Chevon sausages were used as a study model and prepared by incorporating different levels of A. racemosus, namely, T1 (0.25 per cent), T2 (0.50 per cent) and T3 (0.75 per cent) and were vacuum packaged and assessed for various lipid oxidative stability and storage quality parameters under refrigerated (4  ±  1°C) conditions.

Significantly (p < 0.05) lower thiobarbituric acid reacting substances (mg malonaldehyde/kg) values were observed for the products containing A. racemosus in comparison to control indicating a significant effect on the lipid oxidative stability. The products containing A. racemosus also showed significantly (p < 0.05) lower values for various microbiological characteristics like total plate count (log cfu/g), psychrophilic count (log cfu/g), yeast and mould count (log cfu/g), anaerobic count (log cfu/g) and free fatty acid (% oleic acid) values indicating the antimicrobial and antifungal properties of A. racemosus. No significant (p > 0.05) effect was observed on the cooking yield and moisture content of the products. Significantly (p < 0.05) higher scores were observed for various sensory parameters of the products containing A. racemosus during the entire period of storage.

A. racemosus successfully improved the lipid oxidative stability and storage quality of the model meat product without compromising the sensorial characteristics and has a great potential as a novel natural preservative in muscle foods.

Pomegranate rind has been reported to have strong antioxidant and antimicrobial properties. The study was conducted to evaluate the possibility of using pomegranate rind extract as an efficient alternative to synthetic antioxidants and preservatives in fat-rich meat products, which are highly susceptible to lipid oxidation.

Tabak-Maaz, a fat-rich meat product, was used as a model system and treated with different concentrations of pomegranate rind extract (0.5, 1.0 and 1.5 per cent) and aerobically packaged within low-density polyethylene pouches and assessed for lipid oxidative stability and storage quality under refrigerated (4 to 1°C) conditions. The products were evaluated for various physicochemical, microbiological and sensory parameters at regular intervals of 0, 7, 14 and 21 days.

Pomegranate rind extract showed a significant (p < 0.05) effect on the lipid oxidative stability, as the treated products exhibited significantly (p < 0.05) lower TBARS (mg malonaldehyde/kg) values. A significant (p < 0.05) effect was also observed on the microbiological characteristics of the products, as treated products showed significantly lower values for microbial and yeast and mould counts and for free fatty-acid (% oleic acid) values. Sensory parameters showed significant (p < 0.05) decreasing trend for both control as well as treated products throughout the period of storage; however, significantly (p < 0.05) higher scores were observed for pomegranate rind extract-treated products when compared to the control.

Pomegranate rind extract successfully improved the lipid oxidative stability and storage quality of the products during refrigerated (4 ± 1°C) storage and may be commercially exploited by the meat industry as an efficient alternative without adversely affecting the sensory quality of the products.

The purpose of this study was to assess the preservative potential of Tinospora cordifolia as a novel natural preservative in muscle foods.

Chevon sausages were used as a model system and were prepared by incorporating different levels of T. cordifolia, namely, T1 (0.25 per cent), T2 (0.50 per cent) and T3 (0.75 per cent), and assessed for lipid oxidative stability and storage quality under refrigerated (4 ± 10°C) conditions.

Lipid oxidative stability showed a significant improvement as the products incorporated with T. cordifolia exhibited significantly (p = 0.001) lower thiobarbituric acid reacting substances (mg malonaldehyde/kg) in comparison to control. A significant improvement was also observed in the microbial stability as T. cordifolia-incorporated products showed significantly lower values for total plate count (log cfu/g, p = 0.001), psychrophilic count (log cfu/g, p = 0.003), yeast and mould count (log cfu/g, p = 0.02) and free fatty acid (percentage of oleic acid, p = 0.01). Significantly higher scores were observed for various sensory parameters of the treated products during storage.

Tinospora cordifolia successfully improved the lipid oxidative and microbial stability of the model meat product and may be commercially exploited as a novel preservative in muscle foods.

This paper aims to to explore the possibility of utilization of Ipomoea batatas as a novel binding agent for hot-set restructured meat products. Further, green coffee bean (GCB) extract was used as a natural ingredient to improve the lipid oxidative stability and storage quality of the developed restructured mutton blocks.

Restructured mutton blocks were used as a model and were prepared by incorporating different levels of I. batatas, namely, 1, 3 and 5 per cent and analyzed for various quality parameters. Restructured mutton blocks containing optimum level of I. batatas were further treated with GCB (1 per cent) extract as a natural ingredient and assessed for various lipid oxidative stability and storage quality parameters under refrigerated conditions (4 ± 1°C).

Restructured mutton blocks containing 3 per cent level of I. batatas were optimized as best on the basis of various quality parameters. Although a significant declining trend was observed in the sensory characteristics with storage; however, the products containing GCB extract showed significantly (p < 0.05) higher acceptability. The mean scores for overall acceptability for products with GCB extract on day 0 was 7.4 ± 0.1 and for control was 7.3 ± <0.1. Significantly (p < 0.05) lower thiobarbituric acid reacting substances (TBARS, mg malonaldehyde/kg) and free fatty acid (FFA, % oleic acid) values were observed for the products containing GCB extract. The mean TBARS and FFA values for products with GCB extract on day 0 were 0.2 ± <0.1 and 0.08 ± <0.1 and for control were 0.3 ± <0.1 and 0.09 ± <0.1, respectively. The restructured mutton blocks containing GCB extract also showed significantly (p < 0.05) lower values for various microbiological characteristics like total plate count (log cfu/g) and psychrophilic count (log cfu/g).

The results showed herein indicate a promising industrial application of I. batatas (3 per cent) as a binding agent for restructured meat products and GCB extract (1 per cent) as a novel natural ingredient for improved lipid oxidative stability and storage quality.

The purpose of this study is to explore the possibility of utilization of lemon peel extract as a natural antioxidant source in muscle foods. The products incorporated with lemon peel extract were assessed for various oxidative stability and storage quality parameters.

The study was designed to evaluate the effect of lemon peel extract on the oxidative stability and storage quality of Tabak-Maz, a popular traditional meat product. The products were prepared and treated with different concentrations of lemon peel extract (0.5, 1, 1.5 per cent) and were aerobically packaged in low-density polyethylene pouches and assessed for lipid stability and storage quality parameters under refrigerated (4 ± 1°C) conditions.

Lemon peel extract showed a significant (p < 0.05) effect on the lipid stability of the products as the treated products exhibited significantly (p < 0.05) lower thiobarbituric acid-reactive substances (TBARS) (mg malonaldehyde/kg) and free fatty acid (FFA) (per cent oleic acid) values for the entire period of storage. A significant (p < 0.05) effect was also observed on the microbiological characteristics of the products, as lemon peel extract treated products showed significantly (p < 0.05) lower values for total plate count, psychrophillic count and yeast and mould count throughout the period of storage. Coliforms were not detected throughout the period of storage. Significantly (p < 0.05) higher scores were observed for various sensory parameters of the treated products.

Lemon peel extract successfully improved the oxidative stability and storage quality of Tabak-Maz during refrigerated (4 ± 10°C) storage and may be commercially exploited as a natural antioxidant source in muscle foods.

The purpose of the study was to explore the possibility of utilization of epigallocatechin-3-gallate (EGCG) as a novel preservative in cheese. EGCG has strong antioxidant and antimicrobial properties and may be commercially exploited as a natural antioxidant and preservative in cheese like products which are highly susceptible to lipid oxidation.

The study was conducted to evaluate the possibility of using EGCG as a natural antioxidant and preservative in cheese. Kalari, a hard and dry cheese, was used as a model and treated with different concentrations of EGCG (0, 0.05 and 0.10 per cent) and aerobically packaged within low-density polyethylene pouches and assessed for oxidative stability and storage quality under refrigerated (4 ± 1°C) conditions.

EGCG showed a significant (p < 0.05) effect on the lipid oxidative stability as the treated products exhibited significantly (p < 0.05) lower thiobarbituric acid reactive substances (milligram malonaldehyde/kg) values. A significant (p < 0.05) effect was also observed on the microbiological characteristics of the products, as treated products showed significantly (p < 0.05) lower values for total plate count (log cfu/g), psychrophilic count (log cfu/g), yeast and mould count (log cfu/g) and free fatty acid (% oleic acid) values. Coliforms (log cfu/g) were not detected throughout the storage period. Significantly (p < 0.05) higher scores were observed for various sensory parameters of the treated products. EGCG successfully improved the oxidative stability and storage quality of Kalari.

The results suggest that EGCG might be useful to the dairy industry as an efficient alternative to synthetic antioxidants and preservatives.

The purpose of this study was to explore the potential of Aloe vera as a novel source of natural antioxidant and preservative in the muscle foods and to evaluate the effect of Aloe vera on the storage quality of aerobically packaged chicken nuggets.

The Aloe vera pulp was incorporated at various levels, namely, 0, 5, 10 and 15 per cent, replacing lean meat in the formulation. The products were analyzed for proximate composition, physicochemical and sensory parameters. Chicken nuggets incorporated with optimum level of Aloe vera (10 per cent) along with control nuggets (0 per cent Aloe vera) were aerobically packaged and assessed for lipid oxidation, physicochemical and microbiological characteristics under refrigerated (4°C) conditions.

pH, crude protein, ether extract and ash content of the nuggets showed significant (p < 0.05) decreasing trend with increasing levels of Aloe vera; however, there was a significant (p < 0.05) increase in the moisture content, emulsion stability and cooking yield. Aloe vera-enriched nuggets showed significantly (p < 0.05) lower values than control nuggets for almost all the lipid oxidation and microbiological parameters, i.e. free fatty acid, thiobarbituric acid-reactive substances value, total plate count, psychrophillic count and yeast and mould count. No significant (p > 0.05) difference was observed in the sensory parameters of the Aloe vera-enriched nuggets and the control samples throughout the period of storage.

The paper has demonstrated the use of Aloe vera as a potential natural antioxidant without any marginal decline in the sensorial characteristics and nutritive value of the muscle foods.