Response of natural colorants in paprika from conventional, organic and frostdamaged spice peppers to illumination of 2,000, 4,000 and 6,000 lux was studied. The impact of antioxidant supplementation on color retention in such products was also aimed. During 12 months of storage in the dark, the paprika from conventional, organic and frost-damaged peppers lost 60.2, 99.7 and 79.3 ASTA units, respectively. The tocopherol supplementation retarded carotenoid degradation by 28, 32 and 40% in paprika from conventional, organic and frost-damaged peppers, respectively, when stored in the dark. The color retained after 1 month of storage with 2,000 lux illumination was 1.14, 1.33 and 1.56 times higher in supplemented than in nonsupplemented paprika from conventional, organic and frostdamaged peppers, respectively. The magnitude of prevention by antioxidant supplementation increased to 48, 47 and 56%, respectively, when the paprika samples were stored under 6,000 lux illumination. The kinetics study on the effect of fluorescent light on ASTA color loss estimated the apparent zero-order reaction, rate constants and predicted half-life times. PRACTICAL APPLICATIONSSpice paprika is widely used as a source of intensive natural colorants including bioactive compounds that make the product of nutritional importance too. So, it is of special interest from the production, processing and marketing points of view to minimize the loss of carotenoids during storage at ambient conditions. Supplementation with additional antioxidants can increase, to a high extent, the stability of carotenoids toward light-induced degradation and, thereby, can assist in keeping the high quality of stored spice paprika in the markets. Also, improving the storage stability of colorants in organic and frost-damaged paprika is of great economic benefit for producers and technologist.

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A thermostable lactate oxidase (from Aerococcus viridans) based bioreactor was elaborated for l-lactate determination in dairy products. The enzyme was immobilised in a thin-layer enzyme cell connected into a flow injection system with an amperometric detector. The linear measuring range was 0.1-1 mmol/L l-lactate (R 2 = 0.99; linear regression equation: y = 81.2x + 3.3). The detection limit was 0.05 mmol/L. 40 Samples were analyzed per hour. Considering reproducibility: the signals measured were very stable for over 800 injections, after this period the activity of the cell decreased slowly. The method was used for the control of dairy products and for monitoring milk freshness.

Infrared technology has brought a quantum leap in the specialization of non-destructive systems for internal quality inspection of agricultural and food products. Applying near-infrared spectroscopy technique (NIRs) for tracking and estimating some antioxidants such as (Lycopene, β-carotene, Phytoene and Phytofluenxe) in tomato fruit fractions (Exocarp, Mesocarp, Endocarp and Tomato pomace) with prediction model. High-performance liquid chromatography (HPLC) device showed the antioxidant concentrations values within tomato fractions. Where, the maximum and minimum values observed in the mesocarp and exocarp fractions. Also, tomato fractions color analysis confirmed these results. Meanwhile, mesocarp fraction within range dark red color with h°≈ 31.7°, due to increased lycopene concentration, whereas, exocarp fraction was 77.29° for h°, within yellow range. In addition to HPLC and color reference methods were consensus significantly with the different of spectral transformations by the regression of partial least square (PLS). NIR spectra and antioxidant in tomato fractions were taken to establish calibration models for tracking and estimating antioxidant in tomato fractions by using partial least squares (PLS) model. The obtained Coefficients of prediction model (R2p) were 0.95, 0.91, 0.93 and 0.94 for Lycopene, β-Carotene, Phytoene and Phytofluenxe respectively. The values of (RPD) ratio obtained from the standard deviation to the standard error of prediction and also (RER) obtained from the standard error range of prediction model were varied for different tomato fractions and antioxidant content, and found that the NIR model suitable not only for screening the different concentrations values of antioxidants for tomato fractions, but also suitable for most applications including quality assurance.