Food Processing and Storage

It acts as a solidifying agent in culture media and does not serve as a source of nutrients.

It is the correct answer because both deep-freezing and lyophilsation are methods for storing bacterial cultures for long-periods.

This is the correct option. Acids are stored in containers made of glass and ceramics because containers made of glass and ceramics are not attacked by acids.

Placing the freezer at the top facilitates convection currents. Cold air from the freezer sinks, displacing warmer air which rises and gets cooled. This natural convection cycle helps distribute cold air throughout the refrigerator compartment.

An anticaking agent is an additive placed in powdered or granulated materials, such as table salt, to prevent the formation of lumps, easing packaging, transport, and consumption.

A humectant is a hygroscopic substance. When used as a food additive, the humectant has the effect of keeping the foodstuff moist. Humectants are sometimes used as a component of antistatic coatings for plastics. 

A classic molecular solid consists of small, non-polar covalent molecules, and is held together by London dispersion forces (van der Waals forces); a classic example is paraffin wax. These forces are weak, resulting in pairwise interatomic binding energies on the order of 1/100 those of covalent, ionic, and metallic bonds. Binding energies tend to increase with increasing molecular size and polarity.

Sentences 1 and D, both give list of different ingredients used to make ice cream. Therefore, logic allows us to use the two as a pair. This helps to mark D as first sentence in the sequence. Only option (2) fits this prediction, hence, it is the correct answer.

The most preferred method for enumeration of bacteria in milk and food cultures is viable plate count. This gives correct estimate of live bacteria in milk and food samples.

Benzoic acid and its salts (sodium benzoate) are widely used preservatives in acidic foods, beverages, and processed items. They inhibit microbial growth effectively. Acetic acid (vinegar) also preserves but is more commonly used directly in pickling.

To prevent them from spoilage, they are stored at low temperature in a refrigerator where microbes are unable to survive. Lowest level of the refrigerator will prevent them from contaminating other foods.

Chemicals and pickles need to be stored in such vessels, which are non-reactive. If they react, the chemical nature of chemicals and taste of pickles would be spoilt. Plastics are non reactive and thus are used for the same.

Food products are refrigerated because very low temperatures drastically reduce respiration rates in plant tissues, slowing down metabolic processes that cause spoilage. This preservation method maintains flavor, texture, and freshness by preventing the breakdown of sugars, starches, and other compounds that would otherwise occur through respiration and microbial growth at higher temperatures.

The freezer is placed at the top because cold air is denser than warm air and naturally sinks. This placement facilitates convection currents throughout the refrigerator compartment - cold air sinks from the freezer, cooling the food below, while warmer air rises to be cooled again. This natural circulation helps maintain even temperature distribution.

Honey with high sugar concentration does not decay because it creates a hypertonic environment with very high osmotic pressure. When bacteria come into contact with honey, water is drawn out of the bacterial cells through osmosis into the concentrated sugar solution, causing the bacteria to dehydrate and become inactive or die. This is why pure honey can last indefinitely without spoiling.