BetyMefi

13/01/2022

Якщо у тебе вийшло обдурити людину, це не означає, що вона дурень, це означає, що тобі довіряли більше, ніж ти цього заслуговуєш.

13/01/2022

Kitchen Science: from sizzling brisket to fresh baked bread, the chemical reaction that makes our favourite foods taste so good
Have you ever wondered how freshly baked bread gets its a golden brown crust and why it smells so good? Or how nondescript green berries turn into beautiful brown coffee beans with a rich alluring aroma?

The answers to these questions lie in a series of complex of chemical reactions, known as Maillard reactions, which give many foods their familiar flavours and colours. These sensory properties even guide us in how we choose foods and help create our initial perceptions of their quality.

As the name suggests, Maillard reactions were first described by a French physician and biochemist, Louis-Camille Maillard, in 1912. These reactions produce hundreds of chemical compounds that give colour and aroma to some of our favourite foods such as roast meat, potato chips, bread and other bakery products, coffee, chocolate and confectionery.

Maillard reactions occur between amine groups of amino acids or proteins and “reducing” sugars, such as glucose and fructose. These sugars are so named because they act as chemical reducing agents.

These reactions occur most rapidly under conditions of low moisture and at temperatures above about 130℃. Hence, they tend to kick in when we fry, bake, grill or roast.

Maillard reactions are also referred to as browning reactions because of the colour they impart to foods cooked in this way. When meat is grilled or roasted, only the surface is usually hot enough to cause browning. The interior can retain a pinkish colour because the cooking temperature stays below that required for Maillard reactions to occur rapidly.

Foods cooked by boiling or steaming do not turn brown or acquire the complexity of flavours because the temperature only reaches about 100℃. Likewise with cooking in a microwave oven.

The colour of chocolates, fudges and toffees are produced by the reaction of sugars with milk proteins.

The initial products of Maillard reactions are small volatile molecules, which are responsible for the aromas we get from freshly baked bread and coffee. More complex reactions then take place to form larger molecules responsible for the golden to brown colours. This is why the aroma of baking bread is sensed before the crust browns.

The later Maillard reactions are not well understood. We do know that some of the molecules they form have unpleasant flavours and may even be toxic, or the source of carcinogens that occur in charred meat.

The Maillard reaction not only turns it golden brown, but also releases mouth watering aromas. Shutterstock
The colour of flavour
A common misconception is that Maillard reactions are the same as caramelisation. Although both are favoured by conditions of low moisture, caramelisation occurs when sugars are heated to high temperatures in the absence of proteins. The common food flavour and caramel colour is produced by heating a mixture of glucose and sucrose to 160℃.

Maillard reactions don’t only take place in a hot oven though. They can also occur slowly at ambient temperature, resulting in gradual changes to aroma, flavour, colour, appearance, texture, shelf-life and nutritional value of stored foods.

In this way, Maillard reactions are responsible for the colour of honey, as well as deterioration during storage of dry goods such as flour and powdered milk. Maillard reactions are also implicated in the gradual loss of viability of seeds.

Maillard reactions can also have detrimental consequences. Unsightly blemishes may appear on chips after frying if their reducing sugar content exceeds 0.03% of dry matter. Potatoes destined for commercial chip production are carefully monitored to ensure reducing sugars are below this level.

An undesirable product of Maillard chemistry is acrylamide. This is a chemical that can be detected in tiny amounts in a range of fried or roasted foods, including potato chips, coffee, cocoa, chocolate and cereal-based bakery products, sweet biscuits and toasted bread (but not in steamed buns).

Acrylamide has been mentioned as a possible carcinogen, although according to Food Standards of Australia and New Zealand, the body that oversees the safety of our food, there is no direct evidence it causes cancer in humans. Acrylamide does not occur in raw foods or foods cooked by boiling or steaming.

You can almost smell it from here. THINK Global School, CC BY-NC-ND
Beyond the kitchen
Some aspects of the Maillard reaction have long been implicated in human ageing and health conditions.

Examples include loss of elasticity of connective tissue and the appearance dark spots on skin due to effects on collagen, cataract formation due to reactions with the lens protein crystallin, changes in neural proteins contributing to neuropathology and dementia, and glycation of haemoglobin due to elevated blood glucose levels in diabetes.

The importance of Maillard reactions in the kitchen and beyond is well established, even though these reactions are still not well understood more than a century after they were first described.

Nevertheless, we can take advantage of their benefits while continuing to learn about this fascinating area of chemistry.

13/01/2022

Why iron is such an important part of your diet
According to the World Health Organisation, iron deficiency – a condition where your body doesn’t have enough of the mineral iron – is a global public health problem of “epidemic proportions”. It is the single most prevalent nutrient deficiency in developing and industrialised countries, and the most common cause of anaemia.

Anaemia occurs when our red blood cell count and/or haemoglobin levels are too low, resulting in an inability to transport sufficient oxygen throughout the body. Iron is required in order for haemoglobin to transport oxygen.

This week Australian Prescriber published an update on the problem of iron deficiency in Australia. Young women, children and disadvantaged groups are at highest risk. Around 12-15% of women who are pregnant or of reproductive age and 8% of preschool children in Australia are estimated to have iron deficiency anaemia. Iron deficiency without clinical anaemia is even more widespread.

Although vegetarians and vegans are broadly thought of as being at high risk of iron deficiency due to an absence of red meat in the diet, there is little evidence to support this. However restricted diets can confer higher risk if not well balanced, for instance in young overweight women who are trying to lose weight.

Why is iron important?
Iron has an essential role in numerous metabolic pathways in the body, including transport of oxygen in the blood, DNA synthesis, breathing, immune function and energy production.

Symptoms of iron deficiency include tiredness, neurobehavioural disorders like attention deficit hyperactivity disorder and restless leg syndrome (a nervous system disorder that creates an irresistible and sometimes unbearable urge to move the legs), and cognitive impairment in children. Iron deficiency can have a serious impact on health and productivity.

Iron is essential for the developing brain. Iron deficiency with and without anaemia in infancy can have long term negative impacts on brain function and behaviour, and even when levels are corrected, those effects may not be completely reversed.

Maternal anaemia can result in preterm birth, and along with high blood pressure or diabetes can compromise fetal iron levels in pre-term or term infants.

Breastfeeding provides adequate iron to meet infant needs up to the age of six months. However from seven to 12 months the requirement for iron increases significantly (up to 11 milligrams per day), and must be provided via solid food in addition to breast milk.

It’s important to understand problems can be caused by both too little as well as too much iron. Hence iron concentrations in the body are carefully regulated and professional advice must be sought before supplementing with iron.

Causes of iron deficiency
There are lots of complex causes of iron deficiency and anaemia, and they should be carefully investigated before being addressed.

Poor dietary intake is an important cause of iron deficiency, particularly when requirements are increased during infancy, menstruation and pregnancy.

Iron is one of a number of essential nutrients we need to get through our diet. Iron deficiency is therefore one of several casualties of poor dietary patterns in Australia and other westernised countries, characterised by excessive intake of highly processed foods and inadequate intake of nutritious whole foods.

Iron requirements
Dietary iron requirements vary by age and gender. The recommended daily intake (average daily intake that is sufficient to meet the needs of the majority of people) for males varies from eight to 11 milligrams a day for ages one to 18 years, and eight milligrams for all other ages.

Women have higher requirements. For ages 14-50 years, recommended daily intakes range from 15 milligrams (14-18 years) to 18 milligrams a day. Needs are higher during pregnancy, jumping to 27 milligrams per day. However during lactation they are slightly less, at nine to ten milligrams a day.

Iron requirements for vegetarians have been estimated as 1.8 times more than non-vegetarians, however this conclusion was based on limited research.

Dietary sources of iron
Dietary iron is obtained in the form of haem iron or non-haem iron. Haem iron sources include red meat, poultry and fish, while non-haem iron comes from a variety of plant foods such as legumes, wholegrains, green leafy vegetables, nuts, seeds, fresh and dried fruit. These plant sources are core components of both vegetarian and vegan diets.

Non-haem iron is believed to be less available than haem iron. This is because plant foods contain substances that can inhibit absorption of iron.

However, vitamin C can enhance non-haem iron absorption thereby counteracting these inhibitory effects. To address this in your diet, you might like to try:

eating hummus that contains chickpeas and lemon juice
lemon juice drizzled over Indian dal or lentil soup
salads containing high vitamin C sources such as red capsicum or tomato as a side dish
kiwi fruit, strawberries, papaya or a glass of freshly squeezed orange juice with muesli
a side dish of lightly steamed broccoli, cauliflower and/or brussel sprouts - good sources of vitamin C – which can be boosted with lemon juice (plus extra virgin olive oil, garlic and salt for ultimate flavour and nutrition)
mixing baby spinach in salads - green leafy vegetables contain iron and vitamin C, a complete package.
Soaking and sprouting legumes, wholegrains and seeds makes the iron more available from these foods.

It is important to note the absorption of non-haem iron varies considerably, and has been shown to be higher in people who have greater iron requirements. This suggests the body adapts to low iron by increasing its absorption.

Vegetarians who follow a balanced diet have been shown to have higher iron intake than that of non-vegetarians and there is little evidence of lower iron status.

Foods such as red meat, spinach, nuts, seeds and legumes are good sources of dietary iron. Shutterstock
A table of the iron content of foods commonly available in Australia is provided here.

Iron is an essential nutrient with a range of critically important functions in the body and brain. Assessing iron stores and causes of anaemia is complex and should be performed by a professional.

We can ensure adequate intake of iron by eating a healthy balanced diet with a variety of whole foods including (but not limited to) meat as well as plant sources.

13/01/2022

A competitive cooking show puts a humble fermented rice dish on the global stage
It was Kishwar Chowdhury, a competitor and second runner-up on the 13th season of MasterChef Australia, who made a dish called panta bhat internationally famous. A rather humble dish from eastern India (Assam, Odisha and West Bengal) and Bangladesh, one could never have imagined it achieving such a level of critical acclaim.

Panta bhat is cooked parboiled rice that is soaked in cold water and left to ferment. Very often it’s left overnight, although some may even ferment it longer. The rice is then eaten with accompaniments that can vary depending on the economic condition of the family or the individual — ranging from basics like mustard oil, raw onion and green chillies to more elaborate sides like fried fish, batter-fried veggies and potatoes.

How to make panta bhat.
Fermenting in pond water
Ten years ago, panta bhat was associated with several cases of cholera. The dish is a rural staple and popular breakfast in eastern India and Bangladesh, but the use of contaminated water in the preparation of the rice created the perfect conditions for the development of disease.

Using pond water in making panta bhat had been a major cause of the disease. There were several public health campaigns that were specifically designed to prevent the villagers from using pond water, but they were often ineffective.

Despite its role in causing cholera, the popularity of the dish never declined. It’s a cheap meal that needs no refrigeration. Further, one can cook the rice in a pot and soak the leftovers in the same pot. Finally, it is not only cheap and convenient, but also needs very little time to make.

The role of panta bhat is so central to Bengal that there is a popular folkloric figure called Panta Buri — “old woman who eats panta” — who has many adventures after a thief steals her panta bhat. In order to seek justice for the theft, she goes on a long journey to meet the king. On her way, she meets many eclectic characters like a talking knife, a catfish, a bael (a native fruit species) and an alligator. While the characters change in different versions, the context of her journey remains the same.

Panta bhat is a dish that reflects the soul of rural Bengal. Yet the dish has now made it to a very popular television show, and feeds into the growing interest in fermented foods.

Panta bhat is an acquired taste — a penchant for fermented rice is certainly not as widespread as, say, fried potatoes. Immigrant chefs are now pushing us towards bolder taste, a taste that is defiant, and not overshadowed by past colonial ambivalence.

Acceptance through food
Increasingly, immigrants have become unapologetic about their culinary roots. For example, British-Ghanaian chef Zoe Adjonyoh actively discusses issues like colonialism and racism that influence how traditional cuisines are perceived and accepted. Nadiya Hussein became popular after winning the 2015 season of The Great British Bake Off, and helped popularize unique fusion foods through her writing and a series of television cooking shows.

This interest in ethnic cuisines can also be seen in the growing number of food shows and documentaries like Ugly Delicious, High on the Hog, Flavorful Origins and many others that show a growing interest in the subject and a curiosity about authentic culinary storytelling.

We have a very long way to go when it comes to embracing versatile tastes from non-western cultures. In 2019, American national security affairs professor Tom Nichols felt the need to openly disparage Indian food on Twitter.

While it sparked a major controversy, Nichols’ tweet exposed the fault lines of racism that so frequently get expressed in belittling immigrant tastes.

But there is hope, and a lot of curiosity. Instead of trying to alter and adjust their cuisine to existing western standards, young immigrant chefs are learning about their culinary past, and slowly trying to integrate their unique flavours into the growing world of global cuisine in very honest, authentic ways.

Let’s face it, fermented rice with strong mustard oil and spicy green chillies is like a bold, raw taste of defiance.

13/01/2022

13/01/2022