American Journal of Food Science and Technology

The objective of this study was to extract yellow pigment from powder turmeric (Curcuma longa) rhizomes and to evaluate the preservative/antioxidant activity of oil-soluble yellow pigment at concentrations 0.5, 0.1 and 0.2% (w/w) in soybean oil after accelerated oxidation at for 7 days. Soy bean oil free from antioxidant (control) and with 0.02% butylated hydroxytoluene (BHT) (synthetic antioxidant) were used to control. In addition, the effects of combined treatment of water-soluble yellow pigment at ratio 3% (w/w) and gamma irradiation at dose levels of 1, 3 and 5 kGy on the microbiological, chemical and sensory characteristics of chicken breast fillet samples during cold storage (4 ± ) to extend the shelf-life of chicken breast fillets were investigated. The results revealed that the addition of 0.2% oil-soluble yellow pigment caused detectable increments in the oxidative stability of soy bean oil compared with control and other treatments under investigation. The results showed that the ratio of 3% of water-soluble yellow pigment reduced the total bacterial count, Psychrophilic bacteria, lactic acid bacteria, enterobacteriaceae, total molds and yeasts, Staphylococcus aureus, Bacillus cereus, Enterococccus faecalis and Salmonella spp, was not detected in all treated samples. Also, shelf-life periods were increased up to 39 days for chicken breast fillet samples treated by 3% water-soluble yellow pigment and gamma radiation at dose level of 5 kGy. Thus, these results illustrate that yellow pigment extracted from turmeric rhizomes exhibit strong antioxidant and antimicrobial activities. Therefore the use of these yellow pigment extracts in food is recommended to suppress lipid oxidation and may be useful as natural food colorant and preservative and an alternative to synthetic dyes that are harmful to health.

American Journal of Food Science and Technology. 2014, 2(1), 36-47. DOI: 10.12691/ajfst-2-1-6
Pub. Date: February 15, 2014

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Effect of Microwave Power and Sample Thickness on Microwave Drying Kinetics Elephant Foot Yam (Amorphophallus Paeoniifolius)

by Harish A, Vivek B S, Sushma R, Monisha J and Krishna Murthy T P

Original Research

Elephant foot yam was dried under different microwave power ranging from 180 W to 900 W and sample thickness (5-15 mm) to study their effect on microwave drying kinetics. Drying time, drying rate, kinetic rate constant, effective moisture diffusivity and rehydration ratio are various factors studied. Increase in microwave power and decrease in sample thickness increased drying rate and decrease the drying time. The Fick’s diffusion method was also used to model the experimental data. The effective moisture diffusivity values were found to be in the drying conditions range of 4.44 x 10-9 m²/s to 1.17 x 10-7 m²/s. The modified Arrhenius type equation was used to calculate the activation and the resulting range was from 23.47 to 9.23 Wg-1 for varying thickness of the sample. On the other hand, the interaction effect of drying conditions on the average drying rate, drying time, drying rate constant and effective moisture diffusivity with high significance has been explained by the second order quadratic polynomial model.

American Journal of Food Science and Technology. 2014, 2(1), 28-35. DOI: 10.12691/ajfst-2-1-5
Pub. Date: January 31, 2014

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A Comparative Quality Assessment of Five Types of Selected Fishes Collected from Retail Market in Sri Lanka

by B.K.K.K. Jianadasa, P.H. Ginigaddarage and S. Ariyawansa

Original Research

The chemical and microbiological quality and safety of fresh fish obtained from the retail and supermarkets of Sri Lanka were examined. Fresh fish samples (n = 155) of yellowfin tuna (Thunnus albacares), sailfish (Istiophorus platypterus), salaya/ sardine (Sardinella gibbosa, shrimp (Fenneropenaeus indicus) and squids sp (Loligo duvaucelii) were collected from 19 places around the country and evaluated in the laboratory. Samples were analysed for several chemical and microbial quality including total volatile base nitrogen, histamine, total mercury and total plate count. Furthermore, the presence of selected pathogens such as Escherichia coli and Salmonella spp. were detected. In microbiological analysis of samples total plate counts were obtained in the range of 7 x 10³-1.2 x 10⁸cfu/g and 28% of the samples had < 5 x 10⁵ cfu/g. Eight percent of the samples contained > 10³ MPN/g of E. coli and 1 sample contained 500 MPN/g and rest of the samples had < 200 MPN/g with 33% of the samples without E. coli. Twelve percent of samples were positive for Salmonella spp. The range of total volatile base nitrogen (TVB-N) was 15-4883 mgN/100 g and 33% samples were exceeded the maximum acceptable levels. Further considering histamine and mercury level of yellowfin tuna and sailfish, 7% and 4% of samples exceeded the maximum acceptable levels respectively. When considering both microbiological and chemical results it can be seen that majority of the samples are not fit for the human consumption and that counted as; 35% of yellowfin tuna, 47% of sailfish, 35% of sardine, 100% of squids and 53% shrimp.

American Journal of Food Science and Technology. 2014, 2(1), 21-27. DOI: 10.12691/ajfst-2-1-4
Pub. Date: January 29, 2014

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Effect of Thermal Process and Drying Principle on Color Loss of Pineapple Slices

by Edoun Marcel, Kuitche Alexis and Giroux François

Original Research

This study is a contribution to knowledge the color loss of pineapple slices during hot air drying process. The kinetics of color degradation of pineapple (Ananas cosmosus) slices were investigated at 40-60°C and at two drying principles: parallel airflow and traversing airflow. Those temperatures are in the range used to dry the commercial pineapple in tropical humid zone. Color changes associated with heat-treated slice were monitored using Hunter colorimeter (L, a, b, total color difference ΔE). The results showed that temperature had a signiﬁcant eﬀect on the color loss of pineapple slice during the process. At 60°C the color loss is less perceptible. The parallel flow drying process permits us to obtain high color quality during thermal process.

American Journal of Food Science and Technology. 2014, 2(1), 17-20. DOI: 10.12691/ajfst-2-1-3
Pub. Date: January 20, 2014

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Using of Combined Treatment between Edible Coatings Containing Ethanolic Extract of Papaya (Carica Papaya L.) Leaves and Gamma Irradiation for Extending Shelf-Life of Minced Chicken Meat

by Abdeldaiem M. H.

Original Research

The objective of this work was to study the combined effect of edible coating containing ethanolic extract of papaya (Carica papaya L.) leaves at ratio 2% and gamma irradiation at dose levels of 0, 2, 4 and 6 kGy on the chemical, microbiological and sensorial qualities of minced chicken thighs meat during cold storage (4 ± 1°C). Samples of minced chicken thighs meat were divided into three groups; uncoated (control), coated with edible coating (without any additives), and irradiated coated with edible coating samples at 0, 2, 4 and 6 kGy. The obtained results showed that gamma irradiation at 2, 4 and 6 kGy with edible coating reduced the initial total bacterial count, psychrophilic bacteria and lactic acid bacteria and prolonged shelf-life of the samples under investigation. Coated samples and irradiated at 2 kGy reduced the counts of Enterobacteriaceae, Staphylococcus aureus and Bacillus cereus as well as eliminating Salmonella spp, while coated samples irradiated at 4 and 6 kGy completely eliminated these bacteria. On the other hand, combination treatments of minced chicken thighs meat samples showed slight increase in thiobarbituric acid reactive substances (TBARS) post irradiation and during cold storage, but had no effects on their total volatile nitrogen (TVN) contents, while a gradual increase in these chemical quality indexes was observed during cold storage. Finally, combination treatment had no adverse effects on the sensory properties of minced chicken thighs meat samples. Therefore the incorporation of ethanolic extract of papaya leaves in edible coating materials increases the bacterial inhibitory effect of gamma irradiation and is suitable for preservation of minced chicken thighs meat or meat and chicken products.

American Journal of Food Science and Technology. 2014, 2(1), 6-16. DOI: 10.12691/ajfst-2-1-2
Pub. Date: January 19, 2014

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Effect of Natural Aloe Vera Gel Coating Combined with Calcium Chloride and Citric Acid Treatments on Ggrape (Vitis vinifera L. Cv. Askari) Quality during Storage

by Shirin Shahkoomahally and Asghar Ramezanian

Original Research

A novel edible coating based on natural Aloe vera gel in combination with calcium chloride (2%) and citric acid (1%) was used as a mean of preservation to maintain the quality and safety in table grape (Vitis vinifera L. cv. Askari) during cold storage at 4°C temperature and 85 ± 5 % relative humidity for 35 days. Coated clusters delayed the increase in weight loss and soluble solids content, retained greater ascorbic acid and titratable acidity contents than control. Moreover, the sensory analyses revealed beneficial effects in terms of delaying rachis browning and dehydration, which was significantly lower in treated than control fruit.

American Journal of Food Science and Technology. 2014, 2(1), 1-5. DOI: 10.12691/ajfst-2-1-1
Pub. Date: January 10, 2014

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24138 Views9943 Downloads39 Likes6 Citations