Simultaneous HPLC-DAD quantification of vitamins A and E content in raw, pasteurized, and UHT cow’s milk and their changes during storage
نویسندگان
چکیده
An improved extraction and HPLC method for the simultaneous extraction and quantitation of retinol, α-tocopherol, α-tocotrienol and β-carotene was developed to analyze commercial whole/semi-skim/skim samples of raw/pasteurized/UHT milk in transparent plastic/glass bottles and Tetra Brik containers. The sample preparation method required prior saponification at 40oC for 15 min followed by n-hexane extraction. An isocratic acetonitrile:methanol (65:35 v/v) mobile phase and UV detection were chosen for HPLC quantification. The liposoluble vitamin content in raw, pasteurized conventional/organic, and UHT milk ranged 0.055-5.540 (retinol), 0.1351.410 (α-tocopherol), and 0.040-0.850 mg/L (β-carotene). No significant differences (p>0.05) were observed on losses of retinol, α-tocopherol, and β-carotene content in UHT whole milk after 5 days at 4oC in the dark. After 14 days at 4oC in the dark the contents of retinol, α-tocopherol, and β-carotene remained higher in milk with higher fat content and were higher in unopened containers. In UHT whole milk samples containing 0.02% NaN3, retinol (33%) and α-tocopherol (11%) but not β-carotene (2%) decreased significantly (p<0.05).
منابع مشابه
Effect of Technological Treatments on Human-Like Leptin Level in Bovine Milk for Human Consumption
In this experiment, raw milk and commercially available full-cream UHT milk, semi-skimmed UHT milk, skimmed UHT milk, full-cream pasteurized milk, semi-skimmed pasteurized milk and infant formulas for babies between 6 and 12 months of age were analyzed by RIA, with a method using an antibody directed against human leptin and human leptin as reference standard. Raw milk and full-cream UHT milk d...
متن کاملPhysicochemical characteristics and storage stability of clarified butter fat « smen » produced from pasteurized and non-pasteurized milk
Smen is a milk fat isolated by ‘boiling-off’ water. Milk fat was first converted into butter and then into smen. Smen product is utilized for culinary cooking and frying of different food. Smen has better shelf-life than other indigenous dairy products due to its lower moisture content. However, it undergoes deterioration (lipolysis and oxidation of milk fat) causes flavor impairment, lowers nu...
متن کاملDetecting a Rapid Method for Measuring the Proteolytic Activity of Raw and Uht Milk
The relation between age gelation and proteolytic activity was investigated in this study, as proteolysis is considered to be one of the principal factors that cause gelation. Two different methods for measuring the proteolytic activity of milk samples were applied; the measurement of absorbance at 280 nm and the trinitrobenzene sulfonic acid (TNBS) method. The milk samples used were raw and UH...
متن کاملQuantitative determination of thermally derived off-flavor compounds in milk using solid-phase microextraction and gas chromatography.
Many volatile compounds generated during the thermal processing of milk have been associated with cooked, stale, and sulfurous notes in milk and are considered as off-flavor by most consumers. A headspace solid-phase microextraction (HS-SPME)/gas chromatographic technique for the quantitative analysis of thermally derived off-flavor compounds was developed in this study. The extraction temperat...
متن کاملDetermination of Aflatoxin M1 in Pasteurized and UHT Milk in West-Azerbaijan Province of Iran
Background: Aflatoxin M1 (AFM1) as a carcinogenic and toxic compound has considerable significance from public health viewpoint. The aim of this study was to determine the level of AFM1 in pasteurized and UHT milk in West-Azerbaijan province of Iran. Methods: A total of 360 commercial milk samples including 220 pasteurized milk and 140 ultra-high-temperature (UHT) milk were purchased randoml...
متن کامل