scholarly journals Antioxidant effects of green tea extracts on lipid oxidation of half-dried eels

Food Research ◽  
2021 ◽  
Vol 5 (2) ◽  
pp. 62-66
Author(s):  
H.S. Song
Keyword(s):  
Lipid Oxidation ◽  
Green Tea ◽  
Early Stage ◽  
Frozen Storage ◽  
Secondary Oxidation ◽  
Hot Air ◽  
Peroxide Values ◽  
Plastic Bag ◽  
Air Blower ◽  
Antioxidant Effects

In order to explore the change of lipid oxidation of half-dried eels treated with green tea extracts and stored frozen, acid values, peroxide values, carbonyl values, and TBA values were measured. The eels were placed into the plastic bag and soaked for 1 hr in the solution mixed with distilled water and green tea extracts, and also vacuumed and stored frozen at –18 ∼ –20°C for 9 months after being dried with a hot-air blower for 15 hrs at 35°C (Aw 90-91). The control consisted of eels prepared in the same way without any pretreatment. At the end of the 1st month, 3rd month, 6th month, and 9th month, eel oil obtained from the samples were tested for its lipid oxidation. The activity of green tea extracts 1 mL was very similar to Vitamin C 500 μM 0.8 mL. The acid values, peroxide values, carbonyl values, and TBA values of eels treated with green tea extracts were lower than those of the control during 9 months of frozen storage (p<0.05). While the acid values and peroxide values of the control and eels treated with green tea extracts highly increased after the first month of frozen storage, the TBA values increased greatly on the third month of frozen storage. Compared to the control, the pre-application of green tea extracts to half-dried eels meaningfully prevented the generation of TBA compound during the frozen storage (p<0.01). In conclusion, pre-application of green tea extracts was effective in delaying early-stage peracid inducement and preventing the generation of secondary oxidation compounds, such as carbonyl compound and TBA compound, in the course of the drying and frozen storage

scholarly journals Ingredient-Dependent Extent of Lipid Oxidation in Margarine

Antioxidants ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 105
Author(s):  
Sarah Fruehwirth ◽  
Sandra Egger ◽  
Dennis Kurzbach ◽  
Jakob Windisch ◽  
Franz Jirsa ◽  
...  
Keyword(s):  
Citric Acid ◽  
Lipid Oxidation ◽  
Oxidative Stability ◽  
Green Tea ◽  
Acyl Chain ◽  
Green Tea Extract ◽  
Tocopheryl Acetate ◽  
Tea Extract ◽  
The Impact ◽  
Β Carotene

This study reports the impact of margarine-representative ingredients on its oxidative stability and green tea extract as a promising antioxidant in margarine. Oil-in-water emulsions received much attention regarding factors that influence their oxidative stability, however, water-in-oil emulsions have only been scarcely investigated. Margarine, a widely consumed water-in-oil emulsion, consists of 80–90% fat and is thermally treated when used for baking. As different types of margarine contain varying additives, their impact on the oxidative stability of margarine during processing is of pressing importance. Thus, the influence of different ingredients, such as emulsifiers, antioxidants, citric acid, β-carotene and NaCl on the oxidative stability of margarine, heated at 80 °C for 1 h to accelerate lipid oxidation, was analyzed by the peroxide value and oxidation induction time. We found that monoglycerides influenced lipid oxidation depending on their fatty acyl chain. α-Tocopheryl acetate promoted lipid oxidation, while rosemary and green tea extract led to the opposite. Whereas green tea extract alone showed the most prominent antioxidant effect, combinations of green tea extract with citric acid, β-carotene or NaCl increased lipid oxidation in margarine. Complementary, NMR data suggested that polyphenols in green tea extracts might decrease lipid mobility at the surface of the water droplets, which might lead to chelating of transition metals at the interface and decreasing lipid oxidation.

scholarly journals The Effect of Carnosol, Carnosic Acid and Rosmarinic Acid on the Oxidative Stability of Fat-Filled Milk Powders throughout Accelerated Oxidation Storage

Antioxidants ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 762
Author(s):  
Katerina Tzima ◽  
Nigel P. Brunton ◽  
Noel A. McCarthy ◽  
Kieran N. Kilcawley ◽  
David T. Mannion ◽  
...  
Keyword(s):  
Rosmarinic Acid ◽  
Solid Phase ◽  
Thiobarbituric Acid ◽  
Butylated Hydroxytoluene ◽  
Carnosic Acid ◽  
Gas Chromatography Mass Spectrometry ◽  
Peroxide Values ◽  
Antioxidant Potency ◽  
Antioxidant Effects

The in vitro antioxidant effects of the most potent antioxidants of rosemary, namely carnosol, carnosic acid and rosmarinic acid (c: ca: ra) were assessed in fat-filled milk powders (FFMPs) under accelerated conditions (40 °C and relative humidity (RH) 23%) over 90 days. Lipid oxidation was assessed in FFMPs by measuring peroxide values (PVs), thiobarbituric acid reactive substances (TBARS) and aroma volatiles using headspace (HS) solid-phase microextraction (SPME) coupled to gas-chromatography-mass spectrometry (GC-MS). The antioxidant potency of c: ca: ra exhibited a concentration-related effect (308 ppm > 200 ppm > 77 ppm), with the highest concentration being the most effective at controlling the formation of TBARS and PVs. At a concentration of 308 ppm c: ca: ra were particularly effective (p < 0.05) in inhibiting all the evaluated oxidation indices (primary and secondary) compared to the control samples, but in some cases less effectively (p < 0.05) than butylated hydroxyanisole: butylated hydroxytoluene (BHA: BHT) (200 ppm).

scholarly journals Oxidative stability during frozen storage of fillets from silver catfish (Rhamdia quelen ) sedated with the essential oil of Aloysia triphylla during transport

2016 ◽  
Vol 46 (3) ◽  
pp. 560-566 ◽  
Author(s):  
Ana Paula Daniel ◽  
Lauren Fresinghelli Ferreira ◽  
Bruna Klein ◽  
Amanda Roggia Ruviaro ◽  
Andréia Quatrin ◽  
...  
Keyword(s):  
Essential Oil ◽  
Lipid Oxidation ◽  
Oxidative Stability ◽  
Frozen Storage ◽  
Storage Period ◽  
Oxidation Products ◽  
Secondary Products ◽  
Silver Catfish ◽  
Rhamdia Quelen ◽  
Aloysia Triphylla

ABSTRACT: This research aimed to evaluate whether the essential oil of Aloysia triphylla (EOAT) used in vivo as a sedative in the water for transporting fish could increase the oxidative stability of silver catfish (Rhamdia quelen) fillets during frozen storage. The chemical composition of EOAT and of fillets from fish exposed to EOAT (0, 30 or 40µL L-1) were assessed. The pH and lipid oxidation parameters (conjugated dienes, CD; thiobarbituric acid-reactive-substances, TBARS) were evaluated in the fillets throughout the storage period (-18±2oC/17 months). The main compounds found in EOAT were α- and β-citral. Treatment with EOAT did not modify the proximate composition of the fillets, but 40µL L-1 EOAT reduced pH levels when compared to the control fillets (P<0.05). Compared to the control fillets, the fillets from fish treated with 30 and 40µL L-1 EOAT had higher initial CD values (P<0.05), whereas fillets from fish treated with 40µL L-1 EOAT had lower TBARS levels after 6, 9 and 17 months of storage (P<0.05). Results indicated that use of EOAT as a sedative in silver catfish transport water delays the degradation of primary oxidation products (CD) into secondary products (TBARS) in the frozen fillets. This delay in the lipid oxidation rate may increase the shelf life of frozen fillets.

scholarly journals Changes in Aroma Profile of Shiitake Mushroom (Lentinus edodes) during Different Stages of Hot Air Drying

Foods ◽  
2020 ◽  
Vol 9 (4) ◽  
pp. 444 ◽  
Author(s):  
Lei Qin ◽  
Jing-Xuan Gao ◽  
Jia Xue ◽  
Dong Chen ◽  
Song-Yi Lin ◽  
...  
Keyword(s):  
Volatile Compounds ◽  
Sensory Evaluation ◽  
Early Stage ◽  
Organosulfur Compounds ◽  
Lentinus Edodes ◽  
Drying Process ◽  
Shiitake Mushroom ◽  
Hot Air Drying ◽  
Air Drying ◽  
Hot Air

To clarify the changes in the aroma characteristics of shiitake mushrooms (Lentinus edodes) during hot-air drying, volatile compounds of L. edodes were analyzed using sensory evaluation, electronic nose, and purge and trap combined with gas chromatography-mass spectrometry (PT-GC-MS) at different timepoints of the drying process. Results showed that the sensory and volatile profile changed significantly during the drying process at 60 °C for up to 12 h and the drying process could be divided into three stages: early stage (<2 h), middle stage (2–3.5 h) and late stage (>3.5 h). Volatile compounds in fresh L. edodes consisted mainly of ketones and alcohols. The early stage of drying decreased the concentration of ketone and alcohol compounds and promoted the generation of cyclic organosulfur compounds through a series of enzymatic and non-enzymatic reactions, which mainly contribute to the characteristic odor of shiitake mushroom. Partial least squares-discriminant analysis (PLS-DA) showed that the volatile compounds released after different drying times could be divided into four groups, which have been confirmed by sensory evaluation results. The results suggested that the unique flavor of dried mushrooms is mainly due to the activation of enzymes during the drying process, which act on lentinic acid to produce sulfur-containing heterocyclic compounds. We believe that our study makes a potential contribution to the mushroom cultivation and processing industry to achieve an improvement in sensory quality.

scholarly journals Fatty acid composition and influence of temperature on the lipid stability of Arapaima gigas meat

2019 ◽  
Vol 22 ◽  
Author(s):  
Nathália Miranda Coutinho ◽  
Anna Carolina Vilhena da Cruz Silva Canto ◽  
Eliane Teixeira Mársico ◽  
Flávio Alves da Silva ◽  
Luiz Antônio Moura Keller ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Lipid Oxidation ◽  
Nutritional Quality ◽  
Frozen Storage ◽  
Lipid Stability ◽  
Acid Ratio ◽  
Arapaima Gigas ◽  
Malondialdehyde Content ◽  
Atherogenicity Index ◽  
Influence Of Temperature On

Abstract The nutritional quality and lipid stability of Arapaima gigas fillets were investigated. A total of 27.32 kg of A. gigas fillets were obtained and the proximate composition and fatty acid profile immediately determined. In addition, the lipid oxidation parameters were analyzed during 15 and 90 days at 4 °C and –20 °C, respectively. The A. gigas fillets presented high protein (> 15%) and low lipid (< 2%) contents with elevated polyunsaturated fatty acid (PUFAs) contents (43.97%). The nutritional quality indices were the atherogenicity index (0.35), thrombogenicity index (0.28) and the hypocholesterolemic acid/ hypercholesterolemic acid ratio (2.37). Overall, an increase followed by a decrease was observed in the peroxide index (PI) and malondialdehyde content (MDA) results at both storage temperatures ( p < 0.05). The lipid profile exhibited great nutritional quality, however new conservation methods should be investigated for this matrix due to increased lipid oxidation during refrigerated and frozen storage.

Regulatory T-Cell Modulation by Green Tea in Chronic Lymphocytic Leukemia

2013 ◽  
Vol 26 (1) ◽  
pp. 117-125 ◽  
Author(s):  
G. D'arena ◽  
V. Simeon ◽  
L. De Martino ◽  
T. Statuto ◽  
F. D'auria ◽  
...  
Keyword(s):  
Chronic Lymphocytic Leukemia ◽  
Green Tea ◽  
Early Stage ◽  
Epigallocatechin Gallate ◽  
Serum Levels ◽  
Hematologic Malignancies ◽  
Absolute Number ◽  
Lymphocytic Leukemia ◽  
Antitumor Effects ◽  
Report Data

Regulatory T cells (Tregs) are considered to be key immunomodulatory cells of the immune system and are increased in chronic lymphocytic leukemia (CLL). Rai stage 0 identifies patients with early stage CLL for which there is no effective intervention at the present time and a “wait and see” policy is usually adopted. Some biological and clinical studies have reported that green tea constituents, such as epigallocatechin-gallate (EGCG), have antitumor effects on hematologic malignancies including CLL. We report data on a clinical trial in which green tea extracts were given orally to 12 patients with stage 0 CLL and 12 healthy subjects. Ten patients and 10 controls completed the 6-month scheduled therapy. Two patients and 2 controls stopped therapy within 1 month because of tachycardia and epigastralgia. Eight out 10 evaluable patients (80%) showed a reduction of lymphocytosis and absolute number of circulating Tregs, as well. One patient (10%) had a stabilization of lymphocytosis and a reduction of Tregs, and 1 patient (10%) showed an increase of both lymphocytosis and Tregs. Only the non-responding patient progressed after 5 months from the end of green tea administration and chemotherapy was given. Interestingly, both IL-10 and TGF-β serum levels declined throughout the green tea intake period, in both patients and controls. These data seem to indicate that green tea is able to modulate circulating Tregs in CLL patients with early stage of the disease. This can result in the control of lymphocytosis as well as in the prevention of disease progression.

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