جستجوی مقالات مرتبط با کلیدواژه « natural additive » در نشریات گروه « صنایع غذایی »

The aim of this study was to prepare an active film based on polyethylene containing thymol and linalool (%0, 1, 1.5, 2) and use it as packaging in mozzarella cheese. For this purpose, the mechanical and barrier properties of the polyethylene films containing thymol and linalool were analyzed. The results showed that the use of thymol and linalool did not significantly reduce the oxygen permeability of the polyethylene film(p < 0.05). Water vapour permeability was significantly decreased by incorporating linalool and thymol ( 1.5, 2%). Tensile strength and elongation at break were significantly lower (p < 0.05) in polyethylene films containing thymol and linalool than in the control sample. Results show that mozzarella packed with polyethylene films containing thymol and linalool had higher pH and lower acidity than the control sample. The sensory analysis results revealed that coated cheese with polyethylene composed of linalool(1.5%) and thymol 2% was the most attention by panellists compared with others. Based on the results,  films containing thymol and linalool improved the chemical and sensory properties of mozzarella cheese. Therefore, films treated with thymol and linalool can act as active packaging.

Nowadays, the use of tissue culture technique in the production of plant secondary metabolites, such as phenolic compounds, as a natural food additive has become very widespread in the food industry. The aim of this study was to investigate and compare the content of phenolic compounds and antioxidant activity of grapevine Rasha and Qzel Ozum cultivars that were produced by tissue culture under in vitro condition. For this purpose, the terminal buds of grape cultivars were cultured in Murashige - Skoog Medium to produce complete seedlings. Then the methanolic extract was prepared from healthy grapevine leaves and to perform polyphenol composition tests using high performance liquid chromatography with ultraviolet detector, functional groups using Fourier-transform infrared spectroscopy, total phenol content, total flavonoids, total anthocyanins, total carotenoids, acid content, ascorbic acid, free radical scavenging 2,2-diphenyl-1-picrylhydrazyl (DPPH), and hydroxyl  (OH−). The results showed that the amount of total phenolic compounds, total flavonoids, total anthocyanin and total carotenoids of methanolic extracts of Rasha cultivar were 50.35±0.10, 29.72±0.05, 10.41±0.20, and 1.82±0.50 mg/g, respectively, and in Qzel Ozum cultivar were 23.06±0.31, 20.76±0.15, 7.28±0.15, and 94.94±0.42 mg/g, respectively. Ascorbic acid, DPPH and OH− free radicals scavenging activity in methanolic extracts of Rasha leaves were 1.83±0.04, 25.38±1.52, and 75.04±2.74 %, respectively, and in Qzel Ozum leaves were 0.85±0.01, 18.71±2.05 and 68.96±3.61 %, respectively. As a general result, the results showed that the grape leaves of the Rasha cultivar were more than the grapevine leaves of Qzel Ozum cultivar in terms of all studied characteristics (p <0.05). This study also showed that grape leaves are rich in phenolic compounds and natural antioxidants and have the potential to be used in the food and pharmaceutical industries.

Iranian tea industry problems caused to related section damage. Low quality of Iranian black tea and change in sense of consumers taste is one of the reasons. It is produced various teas to attract of consumer opinion. Permissible additives using is not usual in Iranian tea industry (before packaging). One of the natural additives of black tea (i. e. Qare-Qat) evaluated in this experiment. The experiment carried out by using a Split-Plot with two factors in three replications. Storage period was distributed in four levels (0، 2، 4 and 6 months) in main plots and added Qare-Qat fruit amount in subplots in four levels (0، 5%، 10% and 15%). Qualitative traits of tea including organoleptical tests (as made tea apparent، color، perfume، and flavor of tea beverage) and chemical tests (as measuring of theaflavin (TF)، thearubigin (TR)، total color (TC) and brightness (B) of tea) studied. Chemical tests results showed that «Tea + 5 and 10 percent Qare-Qat fruits» treatment has more TF، B and TF/TR ratio than control (pure tea) and this difference was significance in 1% level. However، taste tests did not revealed significance difference between control and tea + Qare-Qat blends.