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The purpose of this paper was to determine total polyphenols (TP), total flavonoids (TF) and (-)-epigallocatechin gallate (EGCG) in five commercial tea extracts and in their infusions at various temperatures (95-60°C) and brewing times (5-30 min).

TP was determined by the Folin–Ciocalteu method, TF by the aluminium chloride colorimetric method and EGCG by HPLC method.

The results showed that White tea – Silver needle had the highest content of TP and EGCG when extracted, but its infusions had very poor concentrations of these compounds. Green tea infusion was better source of TP and EGCG than white or black tea, although its extract did not contain a very high amount of TP compared to the latter two types. Black tea extract had a relatively high content of TP and TF in its extract. Its infusions as well contained higher concentrations of TP than white tea, but lower concentrations of EGCG than all studied teas.

Increasing infusion time and temperature does not necessarily increase the concentration, according to the results. To the authors’ knowledge, this is the first report on comparing these types of tea, especially the white tea, with other well-known teas under various infusion conditions. The extraction of the white tea leaves was also not found in previous works.

Increasingly, interest in and the uptake of herbal infusions has advanced, namely, owing to their bioactive properties and potential links to health. Given this, the purpose of the present review was to collate evidence from human trials for five popular herbal infusions.

The systematic review comprised ten human trials (560 participants), investigating inter-relationships between herbal infusions consumption and health. Only human studies involving German chamomile (Matricaria chamomilla L. Asteraceae), ginger (Zingiber officinale Roscoe Zingiberaceae), lemon balm (Melissa officinalis L. Lamiaceae), peppermint (Mentha x spicata L. Lamiaceae)/spearmint (Mentha spicata L. Lamiaceae) and rosehip (Rosa canina L. Rosaceae) teas were included in the present paper.

Most herbal infusions serve as a good source of flavonoids and other polyphenols in the human diet. Studies included in this paper indicate that herbal infusions (1-3 cups tended to be drank daily; infusion rates up to 15 min) could benefit certain aspects of health. In particular, this includes aspects of sleep quality and glycaemic control (German chamomile), osteoarthritic stiffness and hormone control (spearmint), oxidative stress (lemon balm) and primary dysmenorrhea (rosehip).

Ongoing research is needed using homogenous herbal infusion forms, brewing rates and volumes of water to further reinforce these findings. In the meantime, herbal infusions could provide a useful supplementary approach to improving certain aspects of well-being.

The present paper collates evidence from human trials for five popular herbal infusions.

Tea contains high content of phenolics which are well-known to act as antioxidants. As such, there are claims that the consumption of infusion of tea could help ameliorate free radical-induced diseases; this therapeutic activity would depend on the amount of phenolics that is soluble and the amount that is absorbed and available for metabolic activity when consumed. The purpose of this study is to analyze the content of phenolics and antioxidant activity of some health tea and also to study the effect of addition of sugar and milk on in-vitro availability of phenolics in tea, cocoa and coffee drinks.

Seven brands of health tea, two brands of cocoa drink, one brand each of coffee, powdered milk and sugar were selected. The tea samples were analyzed for pH, titratable acidity, total phenol and antioxidant activity using Folin–Ciocalteau and 202-diphenyl-1-picryl-hydrazil 28DPPH-29-20 reagents. In-vitro simulated digestion modeling stomach and small intestine were carried out on tea infusion, coffee and cocoa drinks with or without sugar, and phenolic availability was analyzed.

The result indicated that pH, titratable acidity and total phenolics ranged from 4.5 to 5.6, 0.167 to 0.837 (as maleic acid) and 1.15 to 1.17 mg/g gallic acid equivalent, respectively. Black tea recorded the highest phenolic content, in-vitro phenolic availability and antioxidant activity. Addition of sugar to black tea and chocolate drink caused a significant decrease in the in-vitro available phenolics, while the addition of milk leads to a significant enhancement.

The data obtained in this study can be used nutritionally and commercially to show the impact of adding sugar or milk on the content of phenolics and their bioavailability in-vitro. The study justifies the claim that tea could help ameliorate free radical-induced health defects.

Assessment of antioxidant activity of food should not be based only on the content of total phenolics but on the amount that is bioavailable in the body system when the food is consumed.

Consumption of tea, cocoa and coffee drinks with milk and sugar have been found to enhance or inhibit phenolics. Therefore, the optimum level of these additives should be determined if the drinks were meant for therapeutic purposes.

Results obtained may provide some useful information for considering the bioavailability of phenolics present in tea and beverages in view of consumption/digestion in our body as well as interference of sugar and milk as the additives.

Although black tea is commonly consumed in Iran, within the last years the popularity of green tea, especially green tea bags, has dramatically increased due to all scientific papers reporting that green tea has benefit impacts on human health. Considering the postulated role of increased dietary oxalate intake on calcium oxalate stone formation, this paper aimed to study the oxalate content of most popular green and black tea bags consumed in Iran.

Five green tea samples and ten black tea samples were purchased from various markets in Tabriz, Iran. The oxalate content of each sample after infusion for five minutes was measured in triplicate using an enzymatic assay. Statistical analysis used: the ANOVA with Tukey's post‐hoc test, and also an independent t‐test were used for statistical analysis.

The oxalate concentration in different brands of green tea bags ranged from 0.73 to 1.75 and from 3.69 to 6.31 mg/240 ml for black tea bags. There were significant differences in oxalate content of different brands, both in green and black tea bags (P<0.001). The mean oxalate content of green and black tea samples also differed significantly from each other (P<0.001).

From the oxalate point of view, consumption of green and black tea bags infusions several times per day may not pose significant health risks in kidney stone patients and susceptible individuals.

The present study was carried out to determine (1) essential minerals, total polyphenols, total flavonoids, moisture and ash of four selected South African herbal teas and (2) the effect of blending bush tea with other known commercial herbal teas.

The method used to determine moisture and ash contents followed that of the Association of Official Analytical Chemists (AOAC). Nine minerals were analyzed using inductively coupled plasma optical emission spectrometry (ICP-OES). The total phenolic and flavonoid contents were determined by Folin–Ciocalteu assay and aluminum chloride colorimetric assay, respectively.

The results of the study demonstrated that bush tea had a high ash content of 8.01% and special tea (9.23%), while honeybush (1.96%) and rooibos tea (2.17%) exhibited a low ash percentage. The mineral content was higher in bush tea and special tea than in rooibos tea and honeybush tea except for sodium, which was higher in rooibos tea. The blending of bush tea with special tea improved its potassium content from 22,937.00 mg/kg to 23,379.20 mg/kg. Blending bush tea with rooibos tea at a ratio of 25:75 increased the flavonoid content to 12.21 µg/mL.

The results of the nutrients composition cannot be generalized as it is influenced by other factors such as soil type and seasons.

Increasing the commercialization of indigenous teas.

The results of the study suggest that bush tea and special tea are nutritionally comparable with South African commercial herbal teas. Thus, the consideration for commercialization of these teas is crucial.

The purpose of this study was to evaluate in vivo the bioavailability of the Ilex paraguariensis polyphenols due to total polyphenols and changes in antioxidant capacity (AOC) in human plasma after an acute intake of 300 ml of an infusion of yerba maté (YM) for 120 minutes. Also, we evaluated the variation of plasma protein or plasma uric acid after the acute intake of YM infusion.

Seventeen healthy young volunteers participated in the determining plasma of total polyphenols concentration (TPC, Folin-Ciocalteu method), plasma AOC for ferric reducing antioxidant power (FRAP) and 2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonic acid diammonium salt [ABTS] methods), plasmatic uric acid and plasma total protein over the 120 minutes test.

It was found that the bioavailability of YM polyphenols during 120 minutes was 49.3 ± 11.9 per cent, the TPC was increased to 6.0 ± 1.5 per cent, the plasma AOC was increased by FRAP 8.3 ± 3.3 per cent and by ABTS 6.0 ± 2.0 per cent and no significant variation of plasma protein or plasma uric acid was found.

Maté polyphenols has a thrifty effect on the natural antioxidant defenses of the body, which are beneficial to human health.

There was no information on the bioavailability of polyphenols in YM infusions prepared in its traditional form as “hot mate”.

A circular letter addressed by the Local Government Board on the 27th October, 1913, to Authorities administering the Sale of Food and Drugs Acts, is printed as an Addendum to a recently issued Report by DR. MACFADDEN, on the work of the Board's Inspectors of Foods during the year 1913–14. This letter relates to the administration of the “Public Health (Milk and Cream) Regulations, 1912,” and points out that by these Regulations “ a definite restriction ” has been placed on the use of preservatives by producers, retailers and others concerned in the milk and cream trade, that no preservative is to be added to milk in‐any case, that no preservative is to be added to cream which is sold as cream, and that the Regulations do not prohibit the sale of cream containing boric acid, borax, or a mixture of these preservative substances, or hydrogen peroxide, provided (1) that it is sold not as cream, but as preserved cream, and (2) that the vessel in which it is sold bears a declaration in the prescribed form, showing the amount and nature of the particular preservative added, the addition to cream of any other preservative substances than those mentioned being prohibited. It is further stated that the object of the Regulations in regard to cream is to secure that preserved cream sold in compliance with the Regulations shall be distinguished at all stages of sale from cream to which no preservative has been added, and that this distinction is important in the interests of the public generally, and particularly in the interests of children and invalids. The italics are ours. In view of this pronouncement by the Board it is pertinent to enquire as to the fate of the extraordinary recommendation made in one of the Board's recent official reports to the effect that a much larger maximum amount of preservative should be allowed in cream during the six warmer months of the year than during the other six months. If a maximum limit is fixed for any period it is plain that the presence of an amount of preservative in excess of that limit is regarded by the Board as capable of rendering the cream injurious to health—at any rate in so far as children and invalids are concerned. It follows, therefore, that the adoption of the recommendation referred to would result in the sale of cream which, on the Board's own showing, must be injurious to health, during the warmer months of the year. The recommendation in question has been put forward as an argument for the defence in cases of prosecution for the adulteration of cream with preservatives, and in view of its official or semi‐official nature, has created unnecessary difficulties for the prosecuting Authorities. It is true that in the Sessions Appeal case of Whale v. Bennett, the character of this recommendation was thoroughly exposed and that the proposal was effectively disposed of, but it is none the less serious and inconvenient that such a suggestion should have been allowed to appear in a Government Report. We hope that we may now be permitted to congratulate the Board on the fact that they have officially repudiated the recommendation in question. The circular letter urges Local Authorities administering the Food and Drugs Acts to see that the “Milk and Cream Regulations, 1912,” are enforced in their districts “by the administrative procedure authorised under the Regulations, and, should necessity arise, by the institution of proceedings under the public health enactments referred to in the note appended to the Regulations.” It is, however, admitted by the Board in this letter that the action taken under the Regulations is independent of the Sale of Food and Drugs Acts and does not affect the action which may be taken under those Acts and that it is open to the Authority “ on consideration of the report of a Public Analyst on a sample of milk or cream to take action either under the Sale of Food and Drugs Acts or under the Regulations,” but the Board considers that “it is generally desirable that in cases in which it appears that the Regulations have been infringed, such action as may be necessary should be taken under the Regulations rather than under the Sale of Food and Drugs Acts.” We are unable to agree with this view. The appeal cases of Cullen v. McNair and Whale v. Bennett have resulted in the decisive establishment of the fact that the presence of boric preservatives in cream to the extent mentioned in those cases renders the adulterated cream injurious to health, and, in all cases where samples of cream are found to contain such amounts of this adulterant, Local Authorities will be well advised to institute proceedings under the Third Section of the Sale of Food and Drugs Act, 1875. The Sixth Section of the Act of 1875 has been shown to be useless by the decision in the Sessions appeal case of Williams v. Friend, whereas under the Third Section notification of the presence of the amount of the adulterant affords no protection to the adulterator, and the law in this respect is not and cannot be over‐ridden by the “ Milk and Cream Regulations, 1912.” The principal blot on the Milk and Cream Regulations, 1912, is that under these Regulations any amount of an injurious preservative may be added with impunity to cream so long as the cream is sold as “ preserved cream ” and the amount of the preservative present is stated on the label—provisions which are perfectly worthless so far as the protection of the ordinary purchaser is concerned.

The London County Council has now passed into history. Often accused of being an overloaded bureaucracy, which it probably was, and a stage for demagogues, of political bias and Socialist waste, it may go unmourned by many, but because of its great influence on local government development in this country and its achievements, it should not be allowed to go unsung. When created by the Local Government Act, 1888, from parts of the counties of Middlesex, Surrey and Kent, it must have seemed at the time something of an administrative anachronism, just as the welding of the remnants of power of the Council with that of Middlesex into a Greater London Council seems so now. Its powers were much greater than those of other county councils and its relations with metropolitan borough councils, constituted by the Local Government Act, 1899, more powerful, the division of functions and authority strongly favouring the L.C.C., especially since 1948 when the National Health Service Act, 1946, transferred the personal health services from the Boroughs. Decentralisation was practised, the area of the L.C.C. being divided into nine divisions, but Greater London long ago outgrew its administrative boundaries, outside which were densely populated areas indistinguishable from London itself, so that re‐organisation was inevitable.

The factors which influence costs of production of food and the prices to the consumer have changed dramatically during this century, but especially since the establishment of trading systems all over the world. Gone are the days when the simple expedients of supply and demand alone governed the situation. The erosion of these principles began at the turn of the century, mainly as a result of the introduction by the rapidly developing industrial power of the USA to protect her own industries against the cheaper products of European countries. They introduced the system of tariffs on imported manufactured goods; it grew and eventually was made to apply to wide sectors of industry. European countries retaliated but the free trade policy of Britain's Liberal government was making the country a dumping ground for all other country's cheap products and surpluses.

With a modest selection of reagents, equipment and test foods — some of which will be normally stocked in the kitchen — students can carry out these practical tests. Most of them will be aware that certain foods develop a brown pigmentation during processing, preparation and cooking. A number of different reactions can cause this browning; reactions between amino‐acids and sugars are responsible for the surface colour of baked bread, caramelisation of sugars produces the colour of toffee and oxidation of some food components can produce discolouration in orange juice. Another familiar browning reaction is that which produces rapid discolouration in cut or bruised fruits and vegetables such as potato, mushroom and apples. These reactions — known as ‘enzymic browning’ because they are catalised by an enzyme present in the food — are the subject of this article.