Cap 1 From Milk By‐Products to Milk Ingredients

1
Ingredients
An ingredient is a part of a recipe that gives valuable properties to the nal product.
Food ingredients are used, for instance, to enhance avour, nutrition and texture.
Thousands of recipes can be found in a wide variety of cookbooks. Some of them
have a long history. Cookbooks have the great advantage that the information is prop-
erly recorded and is not dependent on oral transmission. In antiquity, milk or a part of
it, such as cheese, was already applied in various recipes. Ingredients from milk were
born. In the course of time food habits were developed; for instance, a combination
of cheese and sh was already disliked in Italy in the fth century . The origin of
this lies in the difference in diet between the farmers who prepared the cheese, and
the shermen, who were active on the coast (Sancisi-Weerdenburg, 1995).
Preparation of food is a time-consuming activity. Nowadays, processed foods are
commonly used and the time spent in the kitchen is reduced considerably. A lot
of work in the kitchen has been moved from home to process plants. For example,
sauces and dressings containing various ingredients are sold in huge variety in super-
markets and are rarely prepared at home today. Advantages are that the outcome in
the meal is predictable and its quality is meticulously controlled. The reproducibility
of the processed food relies on the properties of the individual ingredients. They
are produced in specialized ingredient plants. Large-scale manufacture is not only
responsible for a consistent quality, but also the shelf life is improved and the cost
of the ingredients is reduced. Consistency is crucial in processing. Deviations in
quality result in defective products, which is expensive due to loss of raw materials,
energy and process time.
Food labels in today’s supermarkets are an interesting source of information. The
ingredient list reects the choice of ingredients of the manufacturer. Sometimes up
to 50 ingredients are mentioned on the label of the package, drawn from a family
of tens of thousands of food ingredients. Important categories of food ingredients,
including additives, are carbohydrates and sweeteners, oil and fats, vegetable and
animal proteins, water, spices, fruits and avours, stabilizers, emulsiers, vitamins,
From Milk By-Products to Milk Ingredients: Upgrading the Cycle, First Edition. Ruud de Boer.
C⃝2014 John Wiley & Sons, Ltd. Published 2014 by John Wiley & Sons, Ltd.

2CH 1 INGREDIENTS
minerals, colours and preservatives. The numbers are still growing over time. Milk
ingredients represent approximately 5% of the total number of ingredients, based
on the author’s own estimation and various buyers’ guides (Food Product Design,
2007–2008).
The proportion of ingredients from milk used in any given product will depend on
the type of industry considered. In case of one of the largest dairy companies, Fries-
landCampina, the average proportion of milk ingredients in the overall ingredients
list is about 25% (GRA van der Werff, 2010, personal communication). However,
there can be big differences between the various segments of the dairy industry
itself. Large users of all kinds of ingredients are processed cheese, imitation cheese
and liquid milk products. The latter can be complex products, which include, for
instance, fruit yoghurts, drinks and desserts. In summary it can be concluded that
the dairy industry is an important customer of its own ingredients.
Since the publication of the well-known book entitled Byproducts from Milk
(Whittier & Webb, 1950), enormous development has taken place in the dairy
industry. At that time the basis of this industry was dominated by butter, cheese,
liquid milk and cream. The remaining by-products were used as liquid animal feed
or applied as fertilizer. The farmers’ milk price was based on milk fat only; the
value of milk protein was underestimated, while lactose was totally out of the
picture. Changes in consumer preference took place particularly after World War
II. The gradual switch from traditional products to convenience foods posed a new
challenge for the food industry. The dairy industry also took part in this development,
for instance by the introduction of coffee whiteners and desserts. Milk proteins in the
form of caseinates were developed and introduced in all kinds of food products such
as sausages. After 1970 new technologies emerged, of which various membrane
processes were a major breakthrough. Separation of undenatured whey proteins
became a reality. The foaming, gelling and emulsifying properties of undenatured
whey proteins were favourable for new applications. The end uses of this type of
ingredient increased substantially. In selecting an ingredient, adding value became
an important topic for both end users and suppliers. Addition of value can be related
to several properties of the nished product such as texture, avour, nutritional value
and colour, and also to yield.
At the same time the cooling of raw milk on the farm became more common.
The scientic knowledge that cooling of milk (<4◦C) retarded bacterial growth
considerably was translated into the design and adoption of bulk storage tanks. The
prolonged storage of milk made the distance of the farm to the process plant less
critical. It favoured the development of larger plants and kept costs at a reasonable
level. In areas with a large dairy industry, for instance in The Netherlands, ingredient
plants with an enormous capacity could be constructed.
After 1970 environmental issues became more critical than ever as the industry
had to pay for its own pollution. This forced the dairy industry to use all of the milk
constituents and close the cycle as much as feasible. All these developments helped
to create a situation in which by-products such as whey became actual ingredients.

1.1 INGREDIENT LIST 3
An ingredient is a word that can be applied in various ways. In case of ingredients
from milk their application is not limited to food. As will be shown in this chapter
and in Chapter 7 (‘End User’), these include applications in feed, pharmaceuticals
and personal care products. The following denition will be used in this book:
An ingredient is a substance of dairy origin, which is used in the manufacture or
preparation of a variety of food and non-food nished products.
Ingredient is the key concept. A food ingredient distinguishes itself from a food
additive. Milk and milk derivatives are normally considered characteristic ingredi-
ents of a food (EU, 2008). Dairy ingredients are safe to use and in general do not
require extensive permission procedures. The description is simpler than the statu-
tory denition of a food ingredient (EU, 2011) because of the limitation to dairy
origin. Milk powder, which is applied in nished products such as reconstituted
liquid milk and yoghurts, is also included in the denition. Besides food ingredients
the eld of application is much wider as non-food nished products are included too.
Manufacture as well as preparation is mentioned, which reects the possible scale
of operation of the end user. Indeed, it may take some years before an application
reaches maturity.
In the following sections the focus will be on ingredient list, ingredient and cycle,
and ingredient and adding value.
1.1 Ingredient list
Based on various food laws, for instance in the USA and the European Union
(EU), food labels have to contain information about ingredients in order to allow
customers to make more informed purchasing decisions. In most countries it is a
meticulously regulated area. The food label includes a list of ingredients, nutrition
information and shelf life, but it should also hold warnings against allergens. In
this chapter we will restrict ourselves to the list of ingredients as it ts best in the
context of this book. The list of ingredients mostly includes also small percentages
of additives, which are applied for purposes such as texture, avour, colour and
shelf life. Additives, being approved substances, are not considered to have nutritive
value. This is in contrast to natural products like milk, eggs and honey. In the Middle
Ages the whey/serum part of the milk was even believed to have value as a medicine.
It was considered benecial for purication of the human body. Nowadays, a variety
of substances with biological activity have been discovered that have more specic
properties (Hettinga et al., 2011).
Table 1.1 lists the ingredients of a butter pastry with almond paste, apple and
cinnamon. The list includes all the ingredients in descending order of weight. In
Europe food additives are in the vast majority not indicated by their names but with
an E-number. E-numbers are codes for food additives that have been assessed for
use in the EU. Dry milk solids (whey powder and milk protein) and butter fat / oil are

4CH 1 INGREDIENTS
Table 1.1 Ingredient list of butter pastry with apple and cinnamon.
Wheat our (contains gluten)
Raisins
Almond paste (15%)
[almonds, sugar, free range eggs, stabilizer (E420), water, thickening agent (E407)]
Water
Dried apples (9%)
Bread improver
[dextrose, wheat gluten, whey powder (contains milk) butterfat (contains milk) emulsiers
(vegetable origin: E471, E481, E472e), salt with iodine, rye our (puffed, contains gluten),
pea our, glucose syrup, butter oil (contains milk), milk protein, colour agent (E100)]
Baker’s yeast
Cinnamon (0.3%)
Powdered sugar
[dextrose, wheat starch, vegetable fat (palm)]
Vegetable oil (palm)
Preservative (E220)
Source: Courtesy of ‘Lekker Vers Bakkerij’, Obdam (The Netherlands).
included as ingredients from milk. ‘Contains milk’ is added for allergy reasons. The
milk constituents are incorporated in butter pastry at a modest level. Traditionally
they provide avour, texture, structure and colour to bakery products. Although
butterfat is an expensive ingredient it is well-liked by bakers particularly due to its
avour. To comply with European food laws, labels should list the percentage of
ingredients that appear in the name under which the foodstuff is sold (almond paste,
apple, cinnamon). More details regarding legislation are provided in the ‘European
Food Law’ (O’Rourke, 2005).
As was shown by the butter pastry example, long lists of ingredients are not
unusual nowadays. Such complex recipes sometimes have a long history. Ice cream
is given as an example in Figure 1.1. Cold desserts – a mixture of snow and fruit
Cream
Fruit
Sugar
Hand freezer
(1850)
Direct expansion
batch freezer
(1920)
Automation
(1970)
Dairy
ingredients
Sugars and
sweeteners
Flavours
Colours
Vegetable
fats
Stabilizers
Emulsifiers
NUMEROUS VARIETIESTECHNICAL DEVELOPMENTSFIRST PUBLISHED RECIPE
Elizabeth Raffald
(1769)
Pasteurizer
homogenizer
cone (1900)
Continuous
freezer (1930)
Ice cream
home made
Ice cream
industrial
production
Figure 1.1 Ice cream – from simple to complex: recipes and numerous varieties.

1.1 INGREDIENT LIST 5
juices – were already known in China thousands of years ago (Blomdahl, 1982).
The art of ice cream making was brought by Marco Polo from China to Italy in the
14th century. From there it spread to other parts of the world. However, it was not
until 1769 that the rst recipe was published (Raffald, 1769). This ice cream was
homemade and contained three ingredients: dairy cream, fruit and sugar. Nowadays,
most ice creams are made in industrial plants. The USA in particular became the
pioneer country for industrial ice cream manufacturing. In the mid-1800s a hand-
operated freezer was invented (Johnson, 1843). The ingredients were poured into a
container with a stirrer and freezing took place by using a mixture of ice and salt.
In subsequent developments the pasteurizer, homogenizer and the ice cream cone
were introduced. Around 1920 it became possible to replace the ice-salt mixture by a
direct expansion batch freezer. However, the batches varied in quality and the process
was expensive and time consuming. A major step forward in technical development
was the introduction of a continuous freezer (Marshall & Arbuckle, 1995). It took
many efforts, but nally resulted in a simplied production and allowed for the mass
production of ice cream. The process consists of continuously feeding a metered
amount of an ingredient mix and air into one end of the freezing chamber. The
mix is agitated and partially frozen while it passes through the chamber. At the
other end of the freezing chamber it is discharged in a continuous stream. Due to
the incorporation of air the volume of the mix is, for instance, doubled (overrun of
100%); it is dispensed into packages and then placed in a hardening unit to complete
the freezing process. The rst plant was opened in Detroit around 1930 and was
based on a cluster of patents (Vogt, 1930). We shall see the importance of patents
in Chapter 3 (‘Patents’). Automation completed the technical development. In the
meantime product development was more focused on increasing the popularity of
ice cream. Important drivers for improving the recipes were consumer preferences
(diversication in avour, structure and appearance, reduction in calories), cost
(various vegetable fats, whey ingredients) and stability against temperature changes
during storage (heat shock resistance). This resulted in numerous varieties and
complex recipes. Ingredients from milk have an important contribution to the texture
and avour of this complex product, which consists of ice crystals, air bubbles and
unfrozen liquid (Udabage & Augustin, 2003). New developments have come forward
such as an ice-structuring peptide derived from milk protein. This peptide improves
heat shock resistance (Nestec, 2008).
In contrast to the label for butter pastry the list of an infant formula is led by
ingredients from milk. In the early months of life, milk is the only food that infants
can easily digest, so it is critical for survival. As an example the ingredient list of the
infant formula produced by the US company Abbott is included in Table 1.2. The
list of this powder is far more complicated than Nestl´ e’s infant formula that went
on sale in 1868. The latter contained two main components: sweetened condensed
cow’s milk and a specially prepared wheat our. Nowadays the ingredient list is full
of technical feats. Of course, the ‘gold standard’ for infant food is human breast
milk. Because cow’s milk – the basis of most infant formulas – is quite different in
composition, numerous efforts have been made to mimic human milk. The list in