Food Processing

____________ shall be the liquid product prepared by the addition of water to full cream milk powder and shall be subjected to pasteurisation, sterilisation or UHT.

• Premixed milk

• Recombined milk

• Reconstituted milk

• Diluted milk

• Filled milk

is usually added into milk powder to secure the desired emulsion stability, mouthfeel, and particle suspension upon reconstitution.

• Sodium chloride

• Lecithin

• Gellan

• Sodium metabsulphite

• Enzyme

The process of raising or lowering the percent of fat in milk or cream to the desired standard is called ______________.

• enrichment

• fortification

• standardisation

• addition

• thermisation

Disruption of fat globules into much smaller fat globules is defined as ____________.

• standardisation

• centrifugation

• homogenisation

• mixing

• thermisation

Which of the following packaging material should be used in order to avoid off-flavour formation in homogenized milk?

• Transparent glass bottles

• Transparent plastic bottles

• Transparent pouches

• Opaque containers

• Laminated packaging without aluminium layer

Answer explanation

Opaque containers should be used to avoid off-flavor formation in homogenized milk. Light can cause the breakdown of riboflavin in milk, which can lead to the development of a characteristic "sunlight flavor" or "oxidized flavor" in the milk. Opaque containers prevent light from reaching the milk and help to maintain the quality of the product.

Storage of homogenised milk may lead to which of the following development?

• Sediment development

• Protein development

• Fat development

• Cream layer development

• Browning

Answer explanation

Homogenized milk may develop dark sediment at the bottom of the container after standing for 24 h. Sedimentation in homogenized milk is due to the settling of cells, foreign matter and casein particles. In unhomogenized milk, these particles are usually held by the fat globules.

In order to prevent sedimentation in homogenised milk which of the following measure prove effective?

• Heating of milk

• Pasteurisation of milk

• Concentration of milk

• Filtration or clarification of milk prior to homogenisation

• Sterilisation/UHT of milk

Answer explanation

Filtration/clarification of milk prior to homogenisation can remove particles that can contribute to sedimentation in homogenized milk. Homogenization breaks down fat globules into smaller particles, but if there are other particles present in the milk (such as protein aggregates or casein micelles), they can still settle out and contribute to sedimentation. By removing these particles before homogenization, the likelihood of sedimentation is reduced.

The main function of the first stage of homogenisation is _______.

• fat globule reduction

• oxidation

• separation of clusters of fat into individual fat molecules

• off-flavour development

• breakdown protein structure

Answer explanation

The main function of the first stage of homogenization is fat globule reduction. During this stage, the milk is forced through a small orifice or valve under high pressure, causing the fat globules to break up into smaller droplets. This reduces the size of the fat globules and distributes them more evenly throughout the milk, creating a smoother texture and preventing cream separation.

The main function of the second stage of homogenisation is _______.

• fat globule reduction

• oxidation

• separation of clusters of fat into individual fat molecules

• off-flavour development

• breakdown protein structure

Answer explanation

The second stage of homogenization involves subjecting the milk to higher pressure to further break down the fat globules into smaller droplets, allowing for better dispersion and suspension in the milk. This helps to prevent creaming or separation of the fat from the milk, resulting in a more uniform product.

Destruction of which enzyme is used as an index of HTST pasteurization?

• Catalase

• Lipase

• Amylase

• Chymosin

• Alkaline phosphatase