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Grains and Binding agents
grains

Introduction

Function of grains and binding agents

The various grain types are the basis for many derivative (or secondary) products used in the kitchen.  These products will be discussed more fully in section 3 and section 6 following. The uses of the derivative products, that can be prepared and eaten in a great many ways, include the following:

  1. Basic products

Meal and flour are the main components for the preparation of various types of bread, cakes, biscuits, pancakes, porridge and pasta.
Binding agents with a starch base, are used for soup, sauces, puddings and custards in order to thicken them.

  1. Half products

Pasta can be served as an individual dish or accompanying dish.  It can also be used in consommé’s and soups.  There are a great many half products including a great variety of sauces.

fussili ravioli

 

  1. End products

Bread, which is initially an individual product, can also be used in different ways in the kitchen for example as croutons, crostinis, breadcrumbs or bread ‘soldiers’ (fried strips of bread often served with boiled eggs to children).

wholegrain bread  

The nutritional value of grains and binding agents

Grain is extremely nutritious.  It is not only rich in carbohydrate, but also contains fibres, vitamins, minerals and proteins.

The composition of the grain kernel is almost identical in all types of grain and consists of three sections.  First the course outer bran layer.  Inside the bran layer the grain is made up of two main parts.  The smaller part is called the germ, (or seed) from which the new plant will grown.  The larger part, the Endosperm is the starchy store of food from which the germ will feed on while growing.

Grains are rich in starch and contain, among other things, gluten protein.  This endosperm is roughly 80 % of the grain.
The aleuronic layer is a thin, protein rich wall, which separates the endosperm and the bran layer.  This aleuronic layer contains B-vitamins and minerals.
The bran layer, together with the aleuronic layer, is around 15 - 18% of the grain.  The bran layer consists mainly of cellulose and minerals.
The germ is rich in fat, contains the vitamins E and B, also minerals.  The seed is ± 2% of the grain
.

cross section

The nutritional value of meal is dependent on the amount of meal produced after milling 100 kilo of grain: the so-called extraction percentage. Wholemeal is made from the whole kernel, including germ and bran.  It has a high extraction percentage and contains more nutrients than flour.  Flour is meal with a low extraction percentage.  Due to a sieving process, the bran and germ particles are partly or wholly removed.

The nutritional value of binding agents from a starch base, consist of the carbohydrates present. Since binding agents are used in such small proportions, the nutritional value is less important.

Good pastas’ are made from high quality wheat, which contains digestible carbohydrates, proteins, vitamins and minerals.

The nutritional value of bread is dependent on the types of grain used, the milling technique, the preparation technique and the mixture of grain types.   Good quality bread is nutritionally very valuable.

Purchasing grains and binding agentss

When purchasing grain and binding agents, the following points are important to take into consideration:

  1. The various types of grain and binding agents
  2. The physical condition
  3. The quality hallmarks

Normally whole kernels or grain are not purchased, just the products that have been made from them.

  1. The various types of grain and binding agents
    1. The types of grain
    2. The types of basic products: meal and flour
    3. The types of basic products: binding agents
    4. The types of half products: pastas
    5. The types of end products: bread

a. The types of grain

Wheat

Wheat is the most commonly used grain type and eaten mostly in the form of meal or flour.  Groats are broken and sliced or ‘kibbled’ wheat grains. Other groats on the market include oats, rye, barley and buckwheat.  Bulghar wheat is cracked wheat that has been steamed and dried again. Semolina is the name of roughly milled grain and is made from wheat or corn.  Couscous from the North African kitchen is made from (hard) wheat meal. Grain flakes are steeped, steamed (or not) and flattened grain kernels. Roasted flakes are grain that have been flattened then roasted.

wheat

Rye

Rye meal is used to make rye bread and mixed grain varieties of bread.  Rye flour is used in the Dutch breakfast bread – ‘ontbijkoek” and other less common biscuits.  Cracked rye kernels are also called groats.

rye

Oats

Oats are sold in the form of flakes or oatmeal: both are flattened oat kernels.  They are used most commonly in porridge and muesli but also for biscuits.

oats

Barley

Processed barley or pealed barley kernels are called barley.  A further processing of the kernel will produce pearl barley.  Barley flakes are used in porridge.

barley

Corn

Sweet corn is eaten as a vegetable.  Popcorn is made from a special type of sweet corn and cornflakes from flattened corn kernels.  Industrial corn (used also for animal feeding) is a raw material for corn semolina, corn meal and the binding agent cornstarch.  Custard powder is cornstarch to which colouring and flavouring have been added.

corn

Millet

Millet is only available peeled.  The kernels are cooked to a paste or soup and mixed with other grain for the preparation of bread.

Buckwheat

Buckwheat is available in its cracked form (groats) or as meal.  Buckwheat meal contains no gluten and is therefore unsuitable for bread but excellent for pancakes or blini’s. Kasha is roasted, roughly milled or cracked buckwheat that can be used as a side dish or in fillings.

buckwheat

Type of grain

Milled grain kernels

End product

Barley

Pearl barley

Beer

Oats

Oat flakes

Porridge, Muesli

Corn

Corn flour

Oil, Binding agents,
Cattle feed

Rye

Rye meal

Rye bread

Wheat

Wheat flour
Wheat meal
Wheat semolina

Bread/cakes
Starch (binding agents)
Pastries
Flour products

               Table 7-1     various products made from grain kernels

b. The types of basis products: meal and flour

For thousands of years, flour was milled by grinding kernels of grain between stones.  Although stone-ground flour is still found today, most flour is milled by the roller process, in which seeds are alternately put through a series of high- steel rollers and mesh sifters.  The rollers crack the grain, allowing the endosperm (the largest part of the seed) to be separated from the bran and germ.  The endosperm is then ground to the desired consistency.  For whole-grain flours, the bran and germ are returned to the flour at the end of the process.
Although rye, oats, buckwheat, millet and corn are all milled, wheat is by far the most commonly used grain and will be discussed in greater detail.

Varieties

Refined flour
More than 90% of the wheat flour we eat is white, or refined, flour, which consists of only the ground endosperm of the wheat kernel.  White flour is popular because it produces lighter baked goods that whole-wheat flour and has an unequalled ability to produce gluten.

When the bran and germ are removed from the wheat kernel, 22 vitamins and minerals are decreased, along with dietary fibre.  Therefore, many countries require that white flour be enriched with iron and the B vitamins thiamine, riboflavin and niacin.  Some manufacturers add calcium and vitamin D as well.   If the flour has been enriched, it will be made clear on the label.

There are many types of white flour:
All-purpose flour: Also knows a family, plain, white or general-purpose flour.  This is made from a blend of hard and soft wheat.  It has a medium protein and starch content that makes it suitable for either breads or cakes and pastries.  It can be either bleached or unbleached. All-purpose flour is available presifted – that is milled to a finer texture.  This aerates the flour to make it lighter than standard all-purpose flour.  However, all flour, whether labelled presifted or not, has a tendency to settle and become compact in storage and so the benefit of presifting is not always apparent.

Bleached flour: When freshly milled, flour is slightly yellow.  To whiten it, manufacturers either let the flour age naturally or speed up the process by adding chemicals (such as benzyl peroxide or acetone peroxide) that bleach it.  This process gives the flour more gluten-producing potential, but naturally aged flours develop more gluten as well.

Patent flour or bread flour:  is made entirely from hard wheat and is the purest and highest quality commercial wheat flour. High gluten content helps bread rise quickly (it is also available in whole wheat form). It is made from the centre portion of the endosperm. 

Bromated flour: Some manufacturers add a maturing agent such as bromate to flour in order to further develop the gluten and to make the kneading of dough’s easier.  Other maturing agents include phosphate, ascorbic acid and malted barley.

Cake flour:  Finer than all-purpose flour, cake flour is made entirely of soft wheat.  Because of its low gluten content, it is especially well suited for soft-textured cakes and cookies.

Durum flour: Since it has the highest protein content of any flour, durum flour is the basis of nearly all noodles and pastas.

Farina: This granular product, milled from the endosperm of any wheat but durum wheat, is primarily used in breakfast cereals and pastas.

Whole-wheat flour:  Since roller milling separates the bran and the germ from the endosperm, the three components actually have to be reconstituted to produce whole-wheat flour.  The germ and the bran are visible in the flour as minute brown specks.  Whole-wheat flour is higher in fibre, vitamin E, some B vitamins and trace minerals, and protein than enriched white flour.  It is sometimes known as Graham flour in the supermarkets.

Because of the presence of bran, which reduces gluten development, baked goods made from whole-wheat flour are naturally heavier and denser than those made with white flour.  Many bakers combine whole wheat and white flour in order to gain the attributes of both.  Whole-wheat pastry flour is also available.
Stone-milled flour is more susceptible to rancidity than roller-milled flour.  Nutritionally there is no difference.

High-gluten flour: This has about twice the gluten strength of regular bread flour and is used as a strengthening agent with other flours that are low in gluten-producing potential.

Instant flour:  Also called instant blending, quick-mixing or granulated flour, this type of flour pours easily and mixes with liquids more quickly than other flours.  It is used to thicken sauces and gravies, but is not appropriate for most baking because of its very fine, powdery texture and high starch content.

Pastry flour (biscuit or cracker flour): This flour has gluten content slightly higher than cake flour but lower than all-purpose flour.  It is well suited for fine, light textured pastries.

Self-raising flour:  Soft wheat is used to make this flour, which contains salt, a leavening agent such as baking soda or baking powder and an acid-releasing substance.  However, the strength of the leavener in some flours deteriorates within two months, so it’s important to purchase only as much as you need during that period.  Self-rising flour should never be used in yeast-leavened baked goods.

Cake mix (or meal): is a mixture of patent flour, baking powder and flavouring such as vanilla.

c. Types of basis products: binding agents

Within the group of binding agents, products are included from a basis of:

  • Carbohydrates or starch
  • Fats
  • Proteins
  • Pudding powders

Binding agents from a starch basis
Starch is collected from parts of plants such as seeds, roots and bulbs.  These plant parts are first milled and then the starch is extracted by washing then drying.   The starch is a white colour and in powder form.  Sometimes a modifier is added to make the starch more soluble in water.
Examples of binding agents from a starch basis and their uses:

  • Potato starch – produced from peat/moor potatoes. Used to thicken fruit juices or soups
  • Corn flour or cornstarch is made from corn. It is used to thicken milk products, soups and sauces
  • Wheat-starch is made from wheat flour.  It is used as potato starch
  • Sago is extracted from the sago palm tree.  This is used to thicken milk pudding, soups and fruit juices
  • Tapioca is a root starch extracted from the yucca or cassava plants.  It is used to thicken porridges/puddings and soups
  • Arrowroot is root starch extracted from the West Indian Marantha plant.  It is used to thicken soups and fruit juices.

arrowroot

Binding agents from the basis of other carbohydrates.

Some plants do not build up their reserves in starch but in the form of carbohydrates.
Examples of these binding agents (or stabilisers) and their uses are as follows:

  • Agar-agar is extracted from red seaweed.  It is used in the vegetarian kitchen instead of gelatine.
  • Carrageen (a dark purple edible seaweed from the Atlantic coast of Europe and North America – when bleached is known as Irish moss).  This extract is used for puddings and sauces.
  • Carob flour is an extract from the seeds of the Carob tree.  It is used to thicken or stabilise ice.   It can be found in a reform shop in the form of meal.
  • Guar flour is extracted from the seeds of the pods of the Guar plant.  It is used as a stabiliser in ice.
  • Tragacanth is a gum, found in shrubs primarily from the desert highlands of northern and western Iran.
  • Arabic gum is an extraction from a group of Acacia’s plants – tiny shrubs and small trees from Asia.  It is used in the production of sweets and ice.
  • Xanthaangom is produced from various types of carbohydrates produced by a complex bacterial fermentation process. It is used for salad sauces, lemonade syrups and half-margarine products.
  • Pectin is a natural carbohydrate, present in all plants.  In combination with sugar it is marketed as jam sugar.  It is used in the production of jams, marmalade and jelly.

agar agar

Binding agents from a basis of fat:

Fat types of binding agents work only as emulsions.  The most commonly used types are:

  1. Eggs in mayonnaise and salad sauces
  2. Natural lecithin, extracted from soja and used for margarine

Binding agents from a basis of proteins:

  1. Gelatine from bones of slaughtered animals.  This solution is made into gelatine leaves or powdered gelatine.  It is used for aspics, jellies and puddings.
  2. Milk proteins, also known as casein or curd proteins.  Casein is used in prepared sausages, melted cheese, ice, bakers’ products, toppings and sour sauces.

gelatiner

Pudding powders:

Various types of starch can be processed to make pudding powders.  Other ingredients and additives are added to make custards, flan powders and puddings

d. Types of half-products: pastas

Pastas are made in many shapes and forms.  They are natural products made from wheat flour, water and eggs (though sometimes without eggs).  They are nutritional and easily digested, easy to prepare and easily stored for longer periods.
Artificial additives are prohibited, however natural additives such as vegetables or herbs are allowed and used very creatively.  Historically pastas were always made by hand, however nowadays most pasta is made to a high standard industrially.

For industrial processing of pasta, the extraction percentage of the wheat is important.  The grain may not be so finely milled as for ordinary meal, it must be only be milled to fine grains of semolina.  Water is added to the semolina, which encourages it to rise to a dough.  This dough must be soft and easily managed (kneaded) but not so supple that it breaks.  After kneading it is shaped and carefully dried.  If the drying process is too fast, the pasta will fall apart during cooking.  If on the other hand it dries too slowly, it will impair the flavour and can encourage bacterial decay.

Pasta types fall into four main groups:

  1. Dried pasta / Pasta secca

This is the largest category and it is made industrially from hard wheat flour and water. This group includes no end of shapes, sizes and flavours.

  1. Egg pasta / Pasta all’uovo

This, the second largest group, is made from flour and eggs.  This type is either hand made or bought ready made (freshly dried).  This can include industrial production and is used to prepare filled pasta.

  1. Semolina pasta

This type is made from flour (strong), semolina and water.  It is dried to a very hard consistency and is available industrial made.  It can also be hand made.  This type is easy to recognise as it has a different colour than other pastas and has a thin layer of flour on the outside.

  1. Wholemeal pasta

This type is less common (but more nutritional) and is normally made industrially.  It is found in health food shops rather than supermarkets.

fresh pasta dried pasta
    1. Types of end products: bread

In the last twenty years the variety of bread on the market has drastically changed.  There are more than three hundred different types of bread available nowadays.  There are many local and regional varieties as well as many international specialities.  The quality is generally high.  The number of possibilities for making bread is almost unlimited due to the variety of grain types, the extraction percentage, various mixture combinations, different recipes, dough preparations, decorations, fillings, additional ingredients and shapes.

The basic ingredients for bread are divided into main and secondary ingredients.  The main ingredients are essential; the secondary ingredients can be added to improve the quality of the bread.

The main ingredients are: flour and/or meal, moisture, milk and/or water, yeast and/or leavener (leavening or rising agent) and salt or bread salt.

The secondary ingredients are: sugar or honey, bread improvers such as creams and cream powders, margarine, butter or other fat, milk derivatives, gluten, almond paste, fruits such as currants, raisins, ginger and sugared fruit such as orange or lemon peel, olives, herbs, sun-dried tomatoes, cheese and so on.

  1. The physical condition of grain and binding agents

Regarding the physical condition of grain, the following can be noted:

  1. Grains are available in the form of kernels or in flakes – cracked or uncracked, flattened, steamed or roasted
  2. Meal or flour is available fine or rougher milled from various different grains
  3. Binding agents are generally bought in powder form
  4. Pastas are available fresh (not dried) or dried
  5. Bread either baked or ready to “bake off”
  1. The quality hallmarks of grain and binding agents

Basis products: meal, flour and binding agents
Grain, meal, flour and binding agents can decay or rot due to the following:

  • Lactic acid bacteria that for example will turn damp flour rancid
  • Decomposition reactions of fats that especially in wholemeal products, results in them becoming rancid
  • Moulds in and on grains that grow due to a damp and warm store
  • Insects such as flour mites, flour moths, granary weevils or beetles.  If the atmosphere is damp, the flour moth, a grey butterfly, can develop from an egg via caterpillar to a fully developed moth.  The presence of moths can be found in flour in the form of small lumps, usually in the corners of the packaging.

Half products: pasta
Quality pastas’ are only made from ingredients of high quality.  The choice of the extraction percentage of the wheat is particularly important.  There are three quality classes of pasta:

  • Semolina pastas, made from wheat/semolina or rough wheat meal
  • Hard semolina pastas, made from hard wheat semolina
  • Egg dough pastas made from a regulated (legal) amount of eggs, egg yolks or egg yolk powder

End products: bread
Depending on the type of grain used, the type of meal, the baking method and the amount of fat added, can bread keep its specific quality hallmark.  Prepacked bread should have the ‘eat by date’ clearly marked on the label.  Till this date the product should taste good and be edible.   Old bread can be recognised by the reduction in freshness, the decrease in flavour and aroma and by the crust being less crispy and dry.

The handling of grains and binding agents in the kitchen

This section will be discussed in three phases:

  1. The delivery
  2. The preparation
  3. The storage
  1. The delivery

When grain and binding agents are delivered to the kitchen, attention should be paid to the packaging.  The packaging itself must be in tact and undamaged and the sell by/use by dates clearly visible.  Further, the amount ordered should be the amount supplied and the quality norms match the order.

Meal and flour is packed in special paper packaging that varies from 1 kilo to bales of 25 kilos.  Pastas and binding agents are packed in carton or plastic.  Bread is normally pre-packed.

  1. The preparation

Meal and flour are essential for dough and batters and form the basis of bread, pizza, cakes, tarts, biscuits, pancakes, beignets and a whole range of other products.  These products differ in the basic proportions of the ingredients used.  The additional ingredients are variable: milk or water, butter or oil, salt, eggs, yeast or baking powder and in sweet dough, - sugar. The same thing applies to the way the various ingredients are incorporated.   Bread, pizza and pasta dough must be kneaded for a long time whereas short-crust must pastry must be quickly made for best results. Choux pastry is stirred and batters are whipped and stirred.

pasta machine

Binding agents are divided according to their cooking properties:

  • Cold binding agents.  These are binding agents that bind at low temperatures.  An example is agar-agar.
  • Warm binding agents. These are binding agents that bind liquids at high temperatures. An example of this is a roux in a cream soup
  • Clear binding agents.  These are binding agents that keep the product clear or transparent.  An example of this is gelatine in an aspic.
  • Blind binding agents.  These are binding agents that make the product opaque or blind such as flour in a roux.

In the following chart some examples of binding agents and gelatinous binding agents are shown with their specific uses.  Gelatinous agents are not made from grain but they do have the same function.

 

Cold binding

Warm binding

Clear binding

Blind binding

Binding agent

 

 

 

 

1. Potato sago

 

Warm

Clear

 

2. Potato tapioca

 

Warm

Clear

 

3. Potato starch

 

Warm

Clear

 

4. Arabian gum

 

Warm

Clear

 

5. Arrowroot

 

Warm

Clear

 

6. Custard powder

 

Warm

 

Blind

7. Semolina

 

Warm

 

Blind

8. Corn flour

 

Warm

 

Blind

9. Sago

 

Warm

 

Blind

10. Tapioca

 

Warm

Clear

 

Gelatinous binding agents

 

 

 

 

1. Agar agar

Cold

 

Clear

 

2. Gelatine

Cold

 

Clear

 

3. Pectin

 

Warm

Clear

 

The preparation of half products

As stated earlier, pasta is available in many shapes and forms and is often used for particular recipes.  The cylinder shaped ‘maccheroni’ for example is particularly suitable for oven dishes whereas the serrated types are often used to hold a thin sauce around the pasta.  The following are general rules:

  • Thick pastas are served with a relatively piquant sauce
  • Thinner pastas are served with a finer sauce

The preparation of end products
For example: Bread.  Wheat flour or meal contains sugars, starch and proteins.  Enzymes break a small part of the starch to sugars. The yeast in the dough uses this as food. Starch is damaged during the milling process of the grain and can therefore absorb moisture.  At a certain temperature during the baking process the starch stiffens and retains the moisture. The product becomes cooked.
The proteins can be separated into two groups:

  1. The soluble proteins
  2. The insoluble proteins

The soluble proteins stiffen at a temperature above 100ºC, they solidify: they give colour to the bread crust.  The insoluble proteins are called gliadine and glutenine.  They form the gluten in the dough together with the moisture. It is a sticky material that is elastic and stretchy. Use is made of this distinguishing feature during the preparation of bread as they can retain the gasses that the yeast produces.  This enables the dough to rise.

  1. The storage
  • Whole kernels can retain their quality for years if they are stored dry, airy and cool.  Grain which contains a lot of fat such as oats can be stored for at least a year as long as they germ has been removed (this is the case for all grain types).  Roughly milled or processed grains such as flakes, cracked barley and semolina remain good for half a year. Roughly milled whole meal grain which contains the fat-rich germ, can become rancid within a few weeks.
  • Flour and meal must be also be stored dry, cool and airy.  They will retain their quality for two months.  Wholemeal flour or meal cannot be stored for longer than four weeks. Meal and binding agents loose some of their binding properties as they become older.
  • Pay special attention to the sell and use-by dates on the packaging of binding agents.
  • Packaged dried pastas are able to be stored for two years and easy to store.  Fresh or undried pasta should be used quickly.
  • Bread is as its best the day it is baked. Bread must be well packed and stored in a dry area.  Do not store in the fridge.  It can be frozen as long as it is fresh when frozen and stored for a few weeks (properly packaged) at a temperature around ± - 20º C.

Cultivation of grains and binding agents

Grain is produced throughout the whole world.  Each type demands a certain climate and type of soil.  Wheat grows best for example on clay soil and in an average or land climate.  The grain is grown in various ways: wheat, rye and barley grow in sheaf’s, millet kernels grow in plumes or cobs, oats in plumes, corn in cobs and buckwheat in a fruit which is used as a grain.  Much attention is paid to upgrading the seed quality to increase the harvest quantity of grain.

Depending on the climate, grain can be harvested twice a year with the assistance of combine harvesters, which removes the grain.  The remaining straw is pressed into bales or used to improve the soil structure.  The chaff is removed from the grain kernels, it is washed and dried and ready for further processing.