Nong Lam University
Faculty of Food Science and Technology
FOOD SCIENCE SEMINAR
Subject: Effects of Catechin in Meat and Meat Product:
Chelating Activity and Free Radical Scaveging
Instructor: Student’s name – ID:
Vũ Thị Lâm An Đoàn Thị Ngọc Bích – 019125014
Tưởng Thị Hồng Hạnh – 09125042 Đỗ Thị Thu Trang – 09125258
Nguyễn Phương Trúc – 09125193
Ho Chi Minh City
Academic year: 2012 – 2013
EFFECTS OF CATECHIN IN MEAT AND MEAT PRODUCT: CHELATING ACTIVITY AND FREE RADICAL SCAVEGING
Đoàn Thị Ngọc Bích, Tưởng Thị Hồng Hạnh, Đỗ Thị Thu Trang, Nguyễn Phương Trúc
Department of Food Science and Technology, Nong Lam University, Room 200B, Cam Tu Building, Vietnam
Tea catechins (TC) not only have many functions on human health but also have functions in food preservation and food industry. Tea catechins have many effects on food, especially preventing lipid oxidation by its antioxidant ability. In this report, chelating activity of catechins on Fe2+ ions and free radical scavenging ability on chicken meat to prevent rancidity by lipid oxidation at different concentrations and with different types of TC were studied. Keywords: Tea catechin (TC), lipid oxidation, antioxidants.
Catechins are a type of antioxidant found in the greatest abundance in the leaves of the green tea. In smaller amounts, they are found in other foods such as red wine, chocolate, berries, and apples. Polyphenols are the main compounds of green tea and there is a class of polyphenolic flavonoids known as catechins. It means that the catechins found in the leaves of the tea plant are also known as catechin polyphenols. Catechins are the main bioactive constituents of green tea leaves. In dried green tea, there are 30 - 42% of polyphenols, 25 - 35% of catechins and 0.1 - 0.3% of caffeine (Figure 1).
Figure 1: Components of green tea extract
The catechins’s free radical scavenging abilities relates directly to the chemical structure of each compound (Figure 2), namely, gallate group at the 3 position of the C ring, the catechol group (3,4-dihydroxyl groups) on the B ring and the hydroxyl groups at the 5 and 7 positions on the A ring.
Figure 2: Basic structure of catechin gallate
The main catechin group consists of eight polyphenolic flavonoid-type compounds: catechin (C), epicatechin (EC), gallocatechin (GC), epigallocatechin (EGC), catechin gallate (CG), epicatechin gallate (ECG), gallocatechin gallate (GCG), and epigallocatechin gallate (EGCG, Figure 3). Epigallocatechin gallate is the most abundant of the tea catechins and thought to be responsible for the majority of biological activity of green tea extract.
Figure 3: Chemical structures of tea catechins
Catechins have a wide variety of beneficial health effects in vitro, in vivo and clinically: anticarcinogenic, antitumorigenic, antimutagenic, chemopreventative, antiproliferative, anti-inflammatory, antioxidant, antidiabetic, antiallergic, antihypertensive, antiplatelet, antiobesity, hypocholesterolemic, protects against ulcerative colitis, and neurotective. The objective of this study was to investigate the effects of tea catechins on chelating activity and free radical scavenging ability to prevent lipid oxidation in meat and meat products, especially chicken meat. 2. Common Features for Utilisation of Catechins in Foods
2.1.Utilisation of Tea Catechins in the Food Industry
In the food industry, lipid oxidation is a major problem because it causes the development of undesirable rancidity...