Journal of Chemistry and Nutritional Biochemistry

Comparative Studies on the Effect of Boiling and Sprouting on Antioxidant Potential of Onion (Allium cepa) and Garlic (Allium sativum)

2024-05-04T21:34:45+00:00

The sprouted bulbs of Allium plants have been considered to be a waste in many kitchens and these discarded bulbs may contain improved antioxidant potentials as a result of sprouting. The study aimed to investigate how sprouting and boiling affect the antioxidant properties of garlic (Allium sativum) and onions (Allium cepa).

Garlic and onion bulbs were either sprouted for 0–10 days or boiled for 0–8 minutes. The aqueous, methanol, and chloroform of the bulb extracts were then prepared, screened phytochemically, and their ability to scavenge 2, 2-diphenyl-1–picril–hydrazil (DPPH) radicals was employed to evaluate their antioxidant potentials using conventional techniques.

The results show that boiling reduced the samples' total phenol, flavonoid, and ascorbic concentrations significantly (p<0.05) regardless of the kind of solvent utilized. The sprouted methanol extract of onions (7.84 mg/g RE) at day 8 and sprouted methanol extract of garlic (20.16 mg/g RE) at day 10 showed a considerably (p<0.05) higher total flavonoid content. All extracts expressed higher phenolic content at day 8 of sprouting onion and there was a significant increase till day 10 of sprouting garlic. The DPPH Scavenging activity of sprouted garlic and onions has the minimum activity on the 8^th day. However, the comparative measure of ascorbic acid content in sprouted garlic and onions increases but differs slightly, Garlic has its maximum ascorbic content at the 10^th day (8.820mg/g), while Onions has its maximum ascorbic content at 6^th day (6.29mg/g). Generally, the antioxidant potentials of boiled extracts of onion and garlic decreased significantly.

The study revealed that sprouting of onions and garlic could increase their antioxidant capacity while boiling reduces their antioxidant capacity in both samples.

The Concentration and Health Risk Assessment of Selected Heavy Metals (HMs) in African spinach (Amaranthus hybridus) and Tomato (Solanum lycopersicum) Grown around Ashaka Community, Gombe State, Nigeria

2024-05-20T10:37:23+00:00

Heavy metals are completely redundant in the human body and the ingestion of the metals poses a risk of adverse health effects. The study aimed to assess the heavy metal concentration and evaluation of health risks of selected heavy metals in African spinach (Amaranthus hybridus) and Tomatoes (Solanum lycopersicum) products collected from the Ashaka community in Gombe state, Nigeria. Heavy metal concentration was estimated using the Atomic Absorption Spectrophotometer (AAS, Perkin Elmer model 2130). The result showed that the concentrations of copper (Cu), zinc (Zn), lead (Pb), chromium (Cr) and nickel (Ni) were below the permissible level of FAO and WHO standards and the Chinese Department of Protective Medicines limit respectively except for Cadmium (0.210 mg/kg) in African spinach which exceeds the FAO/WHO limit (0.2 mg/kg). The daily plant metal intake for Cd (0.018 - 0.007 mg/kg) and Pb (0.024 - 0.014 mg/kg) were higher than the recommended daily intake of metals but within the tolerable limit. Health risk indices showed high values for Cd, Pb, and Ni, except for Cr, Cu and Zn. The IRS evaluated for all the studied HMs were greater than one (IRS > 1). This implies that exposed populations are susceptible to developing diseases associated with Cd, Pb, and Ni.

Rheological properties and FTIR spectra of olive, chia and garden cress oils exposed to high temperatures for different times

2024-06-30T14:23:54+00:00

Rheological properties, peroxide value, and FTIR spectra of olive, chia, and garden cress oils exposed to high temperatures (150, 175, and 200 ºC) for different times (30, 60, and 120 minutes) were assayed. The shear stress versus shear rate data (at 25 ºC) was fitted to Newtonian, Bingham, and power law rheological mathematical models. Fresh tested oils showed Newtonian flow behavior with correlation coefficients higher than 0.99 and slight non-Newtonian behavior after heat treatment at different temperatures and times. The peroxide values of the tested oils were significantly increased with increasing the temperature and time, excepting the garden cress oil treated at 200 °C. The viscosity is more related to the peroxide value of olive and chia oils (R²= 0.8844 and 0.9768, respectively) than that of garden cress oil (R²= 0.7325). The FTIR spectra showed little decrease in absorption at 2924 and 2855 cm^-1 in olive and garden cress oils, and at 1744 cm^-1 in chia oil after thermal treatment. The vibrations appear at 3200 – 3500 cm^-1 in chia and garden cress oils indicating the presence of peroxides produced during thermal treatment, while it disappeared in olive oil. A peak at 1672 cm^-1 was noticed in olive oil indicating the presence of free fatty acids. A slight difference was observed at 962 cm^-1 between spectra for chia and garden cress oils, indicating the formation of trans fatty acids. In conclusion, the rheological properties and FTIR spectra can be used as good tools to estimate the quality of heated oils.

Analysis of Food Safety Programs in Three University Restaurants at Some Central-Delta Region Universities, Egypt Based on HACCP Principles

2024-08-19T17:26:42+00:00

HACCP programs have been designed to ensure food safety. The concept of food safety knowledge refers to the education and expertise acquired, whereas food safety practices involve the practical application of this knowledge. This research aims to evaluate how university restaurants apply HACCP principles for their food safety programs. Most of the standard operating procedures for HACCP were followed, but only a few records of corrective actions were found. A university restaurant health inspection scores (UNR-1) was high, suggesting that food safety practices were generally well-implemented. Observations of restaurant facilities were positive overall. However, approximately 53.91% of the employees did not adhere to proper handwashing protocols, as outlined in the 2022 Food Code. While most employees washed their hands before handling food, many did not adhere to the proper handwashing procedure. Despite the strong performance of a university restaurant employees of UNR-1, there are still possible risks of food contamination. Restaurant directors and managers can use this information to evaluate their food safety programs and practices, ensuring they effectively provide safe and healthy food to their university students.

Microbial Status and Sanitation level of Food Contact Surfaces (FCSs) of Three University Restaurant Kitchens for Three Public Universities at Central-Delta Region in Egypt

2024-11-05T07:20:24+00:00

The microbiological safety of food is primarily influenced by hygienic practices during food handling and the sanitation of food contact surfaces (FCSs). Consequently, the safety of foods served in university restaurants can be assessed by evaluating the microbiological quality of FCSs. This research aims to evaluate the microbial quality (MQ) and sanitation level of FCSs in the kitchens of three university restaurant kitchens for three public universities in the Central-Delta region of Egypt. A total of 108 swabs were collected from surfaces related to food (preparation tables, dining tables, cutting boards), cooking utensils (pots, knives, trolley tanks, mobile tanks, scoops, colanders), and kitchen equipment (peeling machine, steam pots, bain-maries). The samples were examined for total aerobic colony count (TACC), total Coliform count (TCC), yeast and mold count, Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), Bacillus cereus (B. cereus), Salmonella and Shigella spp. The microbiological analysis revealed that the greatest compliance rates with good hygienic conditions were observed in the FCSs of the UNK-1 university restaurant kitchen. In contrast, the sanitation levels of FCSs in the UNK-2 and NUK-3 university restaurant kitchens were classified as “unsatisfactory.” These findings highlight the need for improvements to enhance the sanitation levels of these university restaurants. Adopting and implementing effective sanitation programs, Good Manufacturing Practices (GMPs), and Hazard Analysis and Critical Control Points (HACCP) is essential to ensuring the safety of food served to students.

Effects of Chitosan-based Coating Enriched with Peanut (Arachis hypogaea) Skin Extract on Physicochemical, Microbiological and Sensory Characteristics of Beef Burger During Cold Storage

2024-11-08T15:41:47+00:00

The current study aimed to create a chitosan-based coating enriched with peanut skin extract (PSE) at a concentration of 0.5, 1 and 1.5%, and evaluate its impact on the physicochemical, microbiological and sensory characteristics of fresh beef burger stored at 4±1°C for 15 days. All coated burgers had significantly higher L*, a* and b* values than the uncoated control during storage. Also, the results showed that application of chitosan coating enriched with 0.5, 1 and 1.5% PSE significantly increased total phenolic content (TPC) and antioxidant activity (AA), inhibited lipid oxidation as evaluated by thiobarbituric acid reactive substances (TBARS) and peroxide value (PV), retarded microbial growth and enhanced sensory characteristics of burger samples. Moreover, the positive effects of PSE on all investigated quality characteristics were proportional with the extract concentration. Therefore, using chitosan-based coating enriched with PSE enhances the stability of beef burger during cold storage and can be utilized in the meat industry.