Open Access Short Research Article

Study of the Light Influence on the Walnuts Oil Quality

Elisavetra Sandulachi, Viorica Bulgaru, Pavel Tatarov

Asian Food Science Journal, Page 1-10
DOI: 10.9734/afsj/2019/v10i130024

This paper represents a statistical processing of experimental studies on the influence of light on the quality of nut oil (Juglans regia L). The conformity of nut oil Calaras and Kogalniceanu, harvested in 2013 and 2015, was analyzed in the Republic of Moldova. The objective of this study was to determine effect of storage conditions (stored at light and dark) on the stability of walnut oil during storage by measuring the Peroxide Values (PV), Acid values (AV), Kinetic Study of Lypid Peroxidation A (PV), Reichert Meissl Number, Polenske Number, Specific Gravity and Refractive Index. The nut oil was obtained by cold pressing in the Department of Food Technology, TUM scientific laboratory, the storage time of nut oil samples in the dark and the light was 6 months, tempering 20-22ºC. The monitoring of the physicochemical indicators was carried out for 2 years in the Institutional project no. 11.817.04.40 Elaboration of methods for the walnut lipids protection (Juglans regia L.) of oxidative degradation, 2012-2014 and project no. 15.817.02.30A Methodological and technical elaboration for the modernization of the walnut processing technology (Juglans regia L.) with the use of biologically active components in functional food «NUCALIM-PROBIO» 2015-2018. It has been established that light is a determining factor in the quality of walnut oil at storage.

Open Access Original Research Article

Production and Quality Evaluation of Yoghurt Enriched with Two Accessions of Passion Fruits (Passiflora edulis f. flavicarpa)

I. E. Mbaeyi-Nwaoha, A. M. Ezeoke

Asian Food Science Journal, Page 1-24
DOI: 10.9734/afsj/2019/v10i130023

Aims: The broad objective of the research produce acceptable yoghurt flavoured with two accessions of passion fruit (pulp and skin) and evaluate its quality (physicochemical, phytochemical, microbiological, selected mineral and vitamin content).

Study Design: The experimental design that was used is Completely Randomized Design.

Place and Duration of Study: The study took place at the Department of Food Science and Technology, University of Nigeria, Nsukka between August 2016 and September 2017.

Methodology: Yoghurt is a diary product obtained from lactic acid fermentation of milk. Yoghurt and two accessions of passion fruit juices (Passiflora edulis f. flavicarpa O. Deg) were processed to formulate enriched yoghurt in the following ratios 90:10, 80:20, 70:30, 60:40 and 50:50. Yoghurt without the passion fruit juice (100:0) served as the control. Based on sensory evaluation, the best samples were subjected to physicochemical, phytochemical, microbiological, selected mineral and vitamin content evaluation using standard methods. The best enriched yoghurt samples were those in the ratio 90:10 and 80:20. Proximate composition of the enriched yoghurt samples significantly (p<0.05) differed with the controls.

Results: Enriched yoghurt showed an increase in the protein content (3.70, 3.52, 3.86, 3.93, 3.94, 3.52%) than control (2.81%). The control had higher fat content (3.43%) than enriched yoghurt (2.93, 3.12, 3.14, 2.78, 3.03 and 2.90%). The ash content ranges from 0.59 - 0.82% while addition of passion fruit juice caused pH to drop from 4.24 in the plain yoghurt to 4.18, 4.20 and 4.23 in the enriched yoghurt. The titratable acidity of yoghurt samples increased from 0.18 in the control to 0.72, 0.54, 0.52, 0.50 and 0.45 in enriched yoghurt. No direct relationship was observed between the pH and the titratable acidity. The total solid content ranges from 4.57-30.03. The phytochemicals were in trace amount. There was no significant (p>0.05) difference in the tannin content. The titratable acidity of yoghurt samples increased from 0.013 µg in the control to 0.015, 0.027, 0.028, 0.016, 0.020 and 0.024 in enriched yoghurt. Significant (p<0.05) difference in the phenolic content value was observed among all the samples. The phenolic content in the yoghurt samples ranges from 0.06 to 0.10 mg/g. The mineral content and vitamin content of the flavoured yoghurt samples significantly (p<0.05) differed with that of the control. An increase in the sodium content was observed in the samples from the control (168.24 mg/100 g) to the enriched sample (209.31, 202.66, 169.48 and 192.82 mg/100 g). Similar increases were  observed for potassium, calcium, magnesium and phosphorus content of the samples. Enriched yoghurt showed an increase in the vitamin C content (6.40, 7.53, 7.29, 7.15 and 7.13 mg/g) than in the control (5.10 mg/g). Vitamin A content ranged from 14.96 µg/100g - 20.67 µg/100 g. The total viable count was higher in the control (5.67 × 105 cfu/ml) than in enriched yoghurt. The mould count of the yoghurt samples varied from 0.33 × 101 cfu/ml - 1.58 × 103 cfu/ml. All the sensory attributes tested in the flavoured yoghurt samples significantly (p<0.05) differed.

Conclusion: Yoghurt enriched with local specie passion fruit juice from pulp, was the most accepted.

Open Access Original Research Article

Antibiotic Sensitivity Profiles of Salmonella typhimurium and E. coli O157: H7 Isolates from Ready to Eat Chicken Meat in Ibadan-Nigeria

Oluwatoyin Hephzibah Ajulo, Olusola Victoria Adetunji, Olugbenga Matthew Ajulo

Asian Food Science Journal, Page 1-17
DOI: 10.9734/afsj/2019/v10i130025

Background: The global increase in the use of antibiotics in poultry and livestock production has significantly resulted in the emergence of antibiotic resistant bacteria. There is a growing global concern of the effect of antibiotic resistance on both animals and humans. The aim of this study was to determine the antibiotic resistance profile of Salmonella typhimurium and E. coli 0157:H7 in ready to eat chicken meat in Ibadan, Nigeria.

Method: A set of 500 pieces of chicken parts were purchased from sampled eateries in Ibadan, Nigeria. Standard microbiological techniques were used to isolate Salmonella and E. coli biochemically and serologically. All confirmed isolates were subjected to in vitro antibiotic susceptibility testing against 8 antibiotics of different classes of Gram negative antimicrobial-impregnated multidisks (ABTEK)

Result: The resistance pattern revealed E. coli 0157:H7 and Salmonella isolates were resistant to 5 drugs namely; Ceftazidime, Cefuroxime, Augmentin, Nitrofurantoin and Ampicillin. Highest resistance of E. coli isolates to Augmentin and Ampicillin were indicated both having a frequency of 11 (84.6%) and least resistance to Gentamicin, Ciprofloxacin and Ofloxacin 0 (0.00%) were indicated. Three antibiotics that showed 100% sensitivity by all the isolates were Gentamicin, Ciprofloxacin and Ofloxacin.

Conclusion: The study revealed that Isolated E. coli and Salmonella strains from ready to eat chicken parts were resistant to five antibiotics; Ceftazidime, Cefuroxime, Augmentin, Nitrofurantoin and Ampicillin and very susceptible to three antibiotics namely; Gentamicin, Ciprofloxacin and Ofloxacin.

Open Access Original Research Article

Characterization of Bacteriophage against Enterococcus faecium Resistant to Vancomycin Isolated from Chicken Skin

Hazzierah Syaffieqah An Nadiah Azlan, Muhajir Hamid, Adelene Ai-Lian Song

Asian Food Science Journal, Page 1-14
DOI: 10.9734/afsj/2019/v10i130026

Aims: To characterize bacteriophages with strong in vitro lytic activity against vancomycin resistant Enterococcus faecium before testing on the chicken skin for their efficacy.

Study Design: An experimental was carried out to characterize two isolated bacteriophages against Enterococcus faecium and test for their efficacy on chicken skin.

Study Place: The study was carried out in Laboratory of Vaccine and Immunotherapeutics, Institue of Bioscience, Universiti Putra Malaysia in Selangor, which is the most populous state in Malaysia.

Methodology: Two host specific lytic phages against vancomycin resistant Enterococcus faecium strain FM8, designated as FM8-P1 and FM8-P2 were physiological characterized. This includes determination of their adsorption rate, multiplicity of infection, and single step growth kinetics. The optimum pH and temperature for both bacteriophages activity were also determined before tested on chicken skin at 4°C and 25°C, which represent chiller and room temperature in poultry production line.

Results: Based on the result of single-step growth kinetics, the latent period of FM8-P1 was 35 min with a burst size of 460 particles per infected cells, while FM8-P2 has a shorter latent period (20 min) but a smaller burst size of 60 particles. The highest adsorption rate for FM8-P1 was 83% and FM8-P2 was 90% at 2 min and 4 min respectively. Both bacteriophages also exihibited a wide range of pH and temperature for their activity.

Conclusion: The specificity, lytic activity and stability of FM8-P1 and FM8-P2 emphasized their potential in effectively eliminating the vancomycin resistant Enterococcus faecium strain FM8. However, further works are required to validate their in situ reliability.

Open Access Original Research Article

Level of Heavy Metals in Selected Vegetables Collected from Ijagun Dumpsite in Ogun State, Nigeria

Damilola Alex Omoboyowa, Clement Olomola Akinnubi, Taiwo Christiana Ajueyisi

Asian Food Science Journal, Page 1-8
DOI: 10.9734/afsj/2019/v10i130027

Wastes from dumpsites constitute a major challenge for plants, human and environmental health. This study investigated the levels of heavy metals in stems and leaves of three (3) Vegetables and soil samples obtained from Ijagun dumpsite, located in Ijebu Ode, Ogun state. The samples were digested with mixed acids and aliquots of the extracts were analyzed for Zinc (Zn), lead (Pb), Cobalt (Co) and Copper (Cu) using the Atomic Absorption Spectrometry (Perkin Elmer A Analyst 700 model). The results obtained showed that there was an increase in the level of selected heavy metals observed in the topsoil compared with the underground soil collected from the dumpsite. The level of the metals present in the topsoil was in the order Zn > Pb >Cu > Co. The stem of Celosia argentea and Cochorus olitorius accumulate more heavy metals compared with the leaf. The level of these selected heavy metals were observed to be far above the WHO/FAO and NAFDAC permissible values in plant except Co in the stem and leaf of Celosia argentea and Talinum triangulae, indicating that the leaf and stem of vegetables from Ijagun dumpsite pose serious health threat to human. However, C. olitorius and C. argentea with high absorption ability for Zn, Pb and Cu could serve as a phytoremediator for soils contaminated with these metals.