Module 7. Butter-making process

Lesson 24

24.1 Introduction

The primary purpose of packaging is to offer butter to the trade and to the consumer in packages of such size, material, form and appearance, as will best meet the requirements and satisfy the preferences of the buyer. In addition, packaging also prevents butter from contamination, weight loss and flavor deterioration. Butter may be packed for wholesale or for consumer packages. Type of packaging, form and material differ for wholesale and retail packaging.

24.2 Packaging of Butter

Objectives of packaging are:

i) To protect butter against contamination.

ii) To prevent loss of weight during storage. (due to evaporation)

iii) To prevent degradation of butter (resulting in off-flavour development)

iv) To increase sales appeal and identification of the content.

The ideal system is to pack the butter as soon as possible after churning otherwise a colour defect known as ‘Primrose’ appear on the surface of butter due to evaporation of moisture. If butter is to be held before packaging, it should be kept covered with a wet muslin cloth and transferred to a tempering room at 5°C.

24.2.1 Packaging material

Packaging material for butter should have excellent barrier properties such as

· It should be moisture proof

· It should be grease proof

· It should be impervious to light

· It should have good strength (to prevent tempering during transportation etc.).

Some of the packaging materials used for butter packaging are

i) Parchment paper – also known as butter paper.

ii) wax coated paper

iii) cellophane

iv) cardboard boxes and teak wood drums lined with food grade plastic

v) Aluminium foil laminates

vi) Lacquered tin cans (it is costly but is advantageous in tropical countries and prevents de-shaping during storage and transportation.)

24.2.2 Techniques of packaging

1. Manual moulding and wrapping

2. Mechanical moulding and hand wrapping

3. Fully automatic units which mechanically moulds, patts and wraps. It reduces labour cost, handling losses and is suitable for large scale operation. The machine can be reset for different size viz. 10, 15, 100, 250 and 500g. Some of the well-known brands of fully automatic butter packaging machines are Kustner, Benhill (both are German) and SIG (Swiss). In these machines, after wrapping, the pat go to carton machine for packing in card boxes and transferred to cold storages (5°C) for 24-48 h and then shifted to low temperature storage (-23 to -29°C).

24.3 Storage of Butter

For the sake of consistency and appearance, butter should be placed in cold store as soon as possible after wrapping and should be chilled to 4°C for 24 to 48 h. Unless this is done, fat crystallization is very gradual and the butter retains its freshly churned consistency and appearance for several days. However, once it has been sufficiently chilled, a subsequent rise in temperature will not make it as soft as it would have been at the same temperature prior to its chilling. The initial freshly churned, somewhat ointment like consistency is transformed to that typical for butter. This change is known as setting of butter. The butter cannot be considered finished until it has been chilled or set. A low storage temperature also improves its keeping quality and reduces the risk of the package being deformed.

As butter is essentially a perishable product it should not be stored longer than necessary. However, when production exceeds demand and also quite often to level out the fluctuation between high flush season production and low summer production, storage of butter becomes unavoidable. For short period butter can be stored at about 4°C but if longer storage is involved it must be deep frozen at -23°C and only best quality butter should be selected for deep freezing. Since solubility of salt is low (35.7% at 0°C), some salt crystallization may occur during storage but the crystals re-dissolve on thawing.

24.3.1 Shrinkage of stored butter

This refers to the loss in weight of butter packs mainly due to evaporation of moisture during storage. The causes of moisture evaporation are:

i. Condition of moisture in butter: incomplete incorporation of moisture in butter due to incomplete working

ii. Size of pat: the smaller the butter pat, greater the surface area/unit volume, which results in greater shrinkage and vice-versa.

iii. Temperature of storage: the higher the temperature, greater the shrinkage and vice-versa.

iv. Relative humidity of storage room: the higher the humidity, lower the shrinkage and vice-versa. However, high humidity favors mold growth and hence it is avoided.

24.4 Transportation of Butter

Quality of butter is largely dependent on temperature. It affects mainly firmness and standing up properties of butter. For transportation of butter from factory to distributors and from distributors to retailers, cold chain is essential to maintain.

Butter may be transported either frozen or chilled. For frozen transportation of butter, temperature range is -16 to -18°C while for chilled transport; temperature range is 1-4°C. Temperatures may deviate from these values, depending on the particular transport conditions.
Butter must be flash-frozen to protect it from losses in quality. The rapid cooling results in the formation of small ice crystals which has no negative effect. If, however, the temperature is reduced very slowly, relatively large ice crystals are formed which can result in losses of quality (crumbly texture).

Last modified: Friday, 5 October 2012, 9:44 AM