Effect of incorporating food-grade lactic acid in minced beef on storage stability and sensory evaluation of the produced patties

The objective of this research is to evaluate quality properties and storage stability of beef patties formulated from fresh beef incorporated with food-grade lactic acid (LA). Fresh beef was purchased from the local market immediately after slaughter, minced and formulated using water incorporated with food-grade lactic acid in concentrations of 0.0% (control); 0.5%; 0.75% and 1.00%. The LA-incorporated formulations were used in the preparation of the patties. The prepared patties were stored at a refrigeration temperature of 5 ºC for 12 days. pH, instrumental color, texture profile analysis (TPA), water activity and total viable count (TVC) were investigated. At the end of the storage period, the patties were cooked and sensory evaluated. The results revealed a significant (p ≤ 0.05) decrease in pH of the control patties from 6.2 ± 0.1 to 5.1 ± 0.2–5.4 ± 0.2 from day 8 to day 12 of the storage time. The same trend was observed in the LA-incorporated patties. The LA-incorporated patties did not show any significant differences (p ≥ 0.05) in the water activity values through all storage time. At the end of the storage time, the control had the TVC value of almost near the spoilage limit, while all LA-incorporated patties had significantly (p ≤ 0.05) lower TVC compared with the control. The results revealed high stability in the physicochemical properties as well as total microbial growth during the storage period. The hardness of the LA-incorporated patties was significantly (p ≤ 0.05) lower than that of the control sample. There was no significant (p ≥ 0.05) difference in overall sensory acceptability of the patties made from beef incorporated with food-grade lactic acid compared to the control. This study suggests that incorporating fresh beef with food-grade lactic acid in the mentioned concentrations could result in great benefits of increasing the storage life of fresh beef products with no effect on sensory quality attributes.The objective of this research is to evaluate quality properties and storage stability of beef patties formulated from fresh beef incorporated with food-grade lactic acid (LA). Fresh beef was purchased from the local market immediately after slaughter, minced and formulated using water incorporated with food-grade lactic acid in concentrations of 0.0% (control); 0.5%; 0.75% and 1.00%. The LA-incorporated formulations were used in the preparation of the patties. The prepared patties were stored at a refrigeration temperature of 5 ºC for 12 days. pH, instrumental color, texture profile analysis (TPA), water activity and total viable count (TVC) were investigated. At the end of the storage period, the patties were cooked and sensory evaluated. The results revealed a significant (p ≤ 0.05) decrease in pH of the control patties from 6.2 ± 0.1 to 5.1 ± 0.2–5.4 ± 0.2 from day 8 to day 12 of the storage time. The same trend was observed in the LA-incorporated patties. The LA-incorporated patties did not show any significant differences (p ≥ 0.05) in the water activity values through all storage time. At the end of the storage time, the control had the TVC value of almost near the spoilage limit, while all LA-incorporated patties had significantly (p ≤ 0.05) lower TVC compared with the control. The results revealed high stability in the physicochemical properties as well as total microbial growth during the storage period. The hardness of the LA-incorporated patties was significantly (p ≤ 0.05) lower than that of the control sample. There was no significant (p ≥ 0.05) difference in overall sensory acceptability of the patties made from beef incorporated with food-grade lactic acid compared to the control. This study suggests that incorporating fresh beef with food-grade lactic acid in the mentioned concentrations could result in great benefits of increasing the storage life of fresh beef products with no effect on sensory quality attributes

Item Analysis of Multiple-choice Questions (MCQs): Assessment Tool For Quality Assurance Measures

Background: Integration of assessment with education is vital and ought to be performed regularly to enhance learning. There are many assessment methods like Multiple-choice Questions, Objective Structured Clinical Examination, Objective Structured Practical Examination, etc. The selection of the appropriate method is based on the curricula blueprint and the target competencies. Although MCQs has the capacity to test students’ higher cognition, critical appraising, problem-solving, data interpretation, and testing curricular contents in a short time, there are constraints in its analysis. The authors aim to accentuate some consequential points about psychometric analysis displaying its roles, assessing its validity and reliability in discriminating the examinee’s performance, and impart some guide to the faculty members when constructing their exam questions bank. Methods: Databases such as Google Scholar and PubMed were searched for freely accessible English articles published since 2010. Synonyms and keywords were used in the search. First, the abstracts of the articles were viewed and read to select suitable match, then full articles were perused and summarized. Finally, recapitulation of the relevant data was done to the best of the authors’ knowledge. Results: The searched articles showed the capacity of MCQs item analysis in assessing questions’ validity, reliability, its capacity in discriminating against the examinee’s performance and correct technical flaws for question bank construction. Conclusion: Item analysis is a statistical tool used to assess students’ performance on a test, identify underperformed items, and determine the root causes of this underperformance for improvement to ensure effective and accurate students’ competency judgment. Keywords: assessment, difficulty index, discrimination index, distractors, MCQ item analysi

Comparison of supercritical fluid and hexane extraction methods in extracting kenaf (hibiscus cannabinus) seed oil lipids.

The objective of this study was to investigate and compare fatty acids, tocopherols and sterols of kenaf seed oil extracted by supercritical carbon dioxide and traditional solvent methods. Fatty acids, tocopherols and sterols were determined in the extracted oils as functions of the pressure (400 bar, 600 bar), temperature (40 °C, 80 °C) and CO2 flow rate (25 g/min) using a 1-L extraction vessel. Gas chromatography was used to characterize fatty acids and sterols of the obtained oils while tocopherols were quantified by HPLC. No differences were found in the fatty acid compositions of the various oil extracts and the main components were found to be linoleic (38%), oleic (35%), palmitic (20%) and stearic acid (3%). Extraction of tocopherols using high pressure (600 bar/40 °C, 600 bar/80 °C) gave higher total tocopherols (88.20 and 85.57 mg/100 g oil, respectively) when compared with hexane extraction which gave yield of 62.38 mg/100 g oil. Extraction of kenaf seed oil using supercritical fluid extraction at high temperature (80 °C) gave higher amounts of sterols when compared with hexane extraction

Monechma ciliatum methanolic extract regulates low density lipoprotein receptor and 3-hydroxy-3- methylglutaryl coenzyme A reductase genes expression in HepG2 cells

Monechma ciliatum methanolic extract (MCME) obtained from Monechma ciliatum seedcake showed high total phenolic compounds with high antioxidant activity. The regulatory effects of MCME at 10, 20 and 50 μg/ml on low density lipoprotein receptor (LDLR) and 3-hydroxy-3-methylglutaryl-coenzyme A reductase (HMGCR) were investigated in human HepG2 cell line using quantitative real-time polymerase chain reaction. LDLR mRNA level was increased significantly by 1.4, 2.6 and 4.3 fold in MCME treated cells at 10, 20 and 50, respectively, compared to untreated cells. Whereas, HMGCR mRNA level was decreased significantly by 38, 63 and 80% in MCME treated cells at 10, 20 and 50, respectively, compared to untreated cells. The effect of MCME was concentration dependent, and different doses showed significant differences in regulation of both LDLR and HMGCR genes. The present study showed that MCME effectively regulated the expression of LDLR and HMGCR genes influencing the cholesterol metabolism in HepG2 cells.Keywords: Antioxidant activity, ß-carotene-linoleic acid assay, 1,1-diphenyl-2-picrylhydrazyl (DPPH), gene expression, low density lipoprotein receptor, 3-hydroxy-3-methylglutaryl-coenzyme A reductase, Monechma ciliatum.African Journal of Biotechnology Vol. 9(36), pp. 5813-5819, 6 September, 201

Preparation and characterisation of protein concentrates from defatted kenaf seed.

Two kenaf varieties QP3 and V36 were used to obtain protein concentrates. Proximate analysis, foaming, water and oil absorption properties were studied. Significant (P<0.05) differences were observed among the two varieties only in their content in oil and carbohydrates. The protein concentrate yield was 13.04% and 10.56%, respectively. The two varieties showed significantly different (P<0.05) water and oil absorption capacities. QP3 showed higher foaming capacity than did V38, and it was increased with increasing salt and sugar concentration. Albumin was the main fraction representing 59.6% and 66.1% in QP3 and V36 varieties, respectively, followed by globulin, which represented 22.6% and 19.1%, respectively. The ratios of albumin, globulin, glutelin and prolamin were significantly different. Based on the data obtained from sodium dodecyl sulphate polyacrylamide gel electrophoresis, the main kenaf seed proteins present in the concentrates were five proteins with molecular weights ranging from 10 to 66. kDa. From differential scanning calorimetry data, QP3 and V36 protein concentrates had similar denaturation temperatures (82.6 and 81.8°C, respectively)

Effect of pretreatment on the proximate composition, physicochemical characteristics and stability of <em>Moringa peregrina</em> oil

The present research work was intended to study the influence of roasting and germination of the kernel seeds of Sudanese Moringa peregrina on the physicochemical characteristics and the oxidative stability of the extracted oil. Roasting was carried out at 180 ˚C for 25 minutes, whereas germination was done at ambient conditions in a wet jute bag for 5–7 days. The oil was extracted using n-hexane in a Soxhlet extraction apparatus. The results show that the oil contains α-tocopherols (152mg/kg) and oleic acid (above 70%) as the major tocols and fatty acids, respectively. Germination reduced the peroxide value and increased the acid value in a significant way (p < 0.05) whereas the opposite trend was noticed in the case of roasting. It is crucial to note that, with the exception of the acid value of the germinated sample, peroxide and acid values remained below one meq O2/Kg of oil and one mg KOH/g of oil, respectively. The oxidative stability of the oil from the roasted sample was increased almost by 80% compared to the raw one. Roasting of the kernels prior to oil extraction is imperative for improving its oxidation resistance and the physicochemical characteristics

Antioxidant activities of phenolic rich fractions (PRFs) obtained from black mahlab (Monechma ciliatum) and white mahlab (Prunus mahaleb) seedcakes

The antioxidant activities of phenolic rich fractions (PRFs) from crude methanolic extract (CME), and its fractions using ethyl acetate (EAF), hexane (HF) and water (WF) of black mahlab (Monechma ciliatum) and white mahlab (Prunus mahaleb) seedcakes were investigated. The total phenolic compounds were found to be higher in white mahlab than black mahlab seedcakes. The antioxidant activity determined by the DPPH method revealed that black mahlab PRFs had the highest antioxidant activity, compared to white mahlab fractions. The presence of antioxidants in the two mahlab PRFs reduced the oxidation of β-carotene by hydroperoxides from these extracts/fractions. The effect of the two mahlab PRFs on the oxidative stability of corn oil at 70 °C was tested in the dark and compared with butylated hydroxyanisole (BHA). The CME performed better antioxidant activity in inhibiting the formation of both primary and secondary oxidation products. The qualitative and quantitative characterisation of phenolic compounds was carried out by HPLC/DAD

Antioxidant activity and phenolic content of phenolic rich fractions obtained from black cumin (Nigella sativa) seedcake.

The antioxidant activities of crude methanolic extract (CME) and its fractions using ethyl acetate (EAF), hexane (HF) and water (WF) of black cumin seedcake were investigated. DPPH radical scavenging activity, β-carotene-linoleate bleaching, and inhibition of corn oil oxidation were used to evaluate the antioxidant capacity. The total phenolics were found to be 78.8, 27.8, 32.1 and 12.1 mg gallic acid equivalents (GAE)/g in EAF, CME, WF and HF, respectively. The CME and EAF exhibited the highest DPPH followed by WF and HF. The extract/fractions showed high effect on reducing the oxidation of β-carotene. The effect of extract/fractions on the oxidative stability of corn oil at 70 °C was tested in the dark and compared with butylated hydroxyanisole (BHA). The oil peroxide and anisidine values were generally lower with addition of PRFs in comparison to a control. The predominant phenolic compounds identified by HPLC-DAD in CME and WF of black cumin seedcake were hydroxybenzoic, syringic and p-cumaric acids

Actividad antioxidante de extractos de torta de aceite de semilla de Sclerocarya birrea

The antioxidant activity of methanolic extracts from Sclerocarya birrea kernel oil meal, extracted using two different methods was evaluated. The extraction was carried out using magnetic stirring of the material in methanol/water (80:20 v/v) overnight followed by two ultra-sonic treatments for 45 min. (Overnight extract, ONEXT) and three ultra-sonic treatments for 45 min. only (Ultra-sonic extract, USEXT), respectively. Three fractions were obtained from each extract and the contents of total phenolic compounds were determined in each fraction according to the Folin-Ciocalteau method as 34.6, 54.8, and 58.6 mg/g of dry product in ONEXT and 29.6, 84.8, 143.9 mg/g in USEXT, respectively. The antioxidant activity of the extracts was evaluated according to the β-carotene-linoleic acid assay, where the extracts and their fractions showed significant effect (pSe ha evaluado la actividad antioxidante de extractos metanólicos de torta de aceite de semilla de Sclerocarya birrea extraídos usando dos métodos diferentes. La extracción se llevó a cabo mediante agitación magnética del material en metanol/agua (80:20 v/v) durante toda la noche seguida de dos tratamientos con ultrasonidos durante 45 min. (extracto ONEXT) y solo tres tratamientos con ultrasonidos durante 45 min. (extracto USEXT), respectivamente. Se obtuvieron tres fracciones de cada extracto y el contenido total de compuestos fenólicos se determinó en cada fracción según el método de Folin-Ciocalteau como 34.6, 54.8 y 58.6 mg/g de producto seco en ONEXT y 29.6, 84.8 y 143.9 mg/g en USEXT, respectivamente. La actividad antioxidante de los extractos fue evaluada mediante el ensayo del β-carotenoácido linoleico donde los extractos y sus fracciones mostraron efectos significativos (

Fatty acid composition and antioxidant activity of oils from two cultivars of Cantaloupe extracted by supercritical fluid extraction

The effect of supercritical fluid extraction (SFE) fractionation of three oil fractions (1st, 2nd, 3rd fraction) on the fatty acid composition and antioxidant activity of oils from two cultivars of cantaloupe were investigated. Rock melon oil (RMO) and Golden Langkawi oil (GLO) were extracted using SFE and the major fatty acids for both cultivars were linoleic, oleic, palmitic, and stearic acid. The SFA decreased from 15.78 to 14.14% in RMO 1st fraction, and MUFA decreased from 18.30 to 16.56% in RMO 2nd fraction, while PUFA increased from 65.9 to 69.30% in RMO 3rd fraction. On the other hand SFA decreased from 16.35 to 13.91% in GLO 1st fraction, and MUFA decreased from 17.50 to 15.57% in GLO 2nd fraction, while PUFA increased from 66.15 to 70.52% in GLO 3rd fraction. The different fractions of the two oils showed high antioxidant activity in reducing the oxidation of pi-carotene in beta-carotene bleaching assay (BCB) and the quenching of 1,1-diphenyl-2-picrylhydrazyl (DPPH)