Sensory Evaluation of Khoa

i. Desirable Attributes of Khoa

a) Colour and Appearance: A good quality khoa, in general, should have uniform whitish colour with perhaps a tinge of brown colour. Khoa made from cow milk, however, has light yellow to deep yellow colour. The surface should be slightly oily/greasy i.e., showing the signs of little free fat. It should not have any foreign matter.

b) Flavour: A typical mildly cooked flavour, similar to that perceived from boiled milk, is most acceptable. The taste should be pleasantly sweet. Good quality product shall not have any abnormal or objectionable flavour.

c) Body and Texture: The texture of khoa depends on its variety. In general a uniform and slightly granular (equal to pinhead size) texture is most desirable. Pindi khoa is required for making burfi and peda in which homogenous texture with very fine grains is required. Pindi khoa has smooth, compact and homogenous texture. Dhap khoa has slightly loose texture with grains of bigger size than that of Pindi khoa. Danedar khoa is used for making kalakand and milk cake in which presence of big grains with brown colour are considered desirable attributes.

ii. Score Card of Khoa

A 100-point score card is more purposeful and objective, hence it is recommended for judging of khoa (Table )

Score card for khoa

iii. Scoring Technique of Khoa

i) Tempering: Khoa should be kept at room temperature for judging purpose. It is, however, desirable to have a constant temperature of about 30oC for consistency in judging throughout the year.

ii) Sampling: A uniform sample weighing about 50 g for each judge is collected from the bulk khoa. Alternatively, the judges may also use a cheese trier to withdraw the khoa sample.

iii) Sequence of observations:

a) The first step in judging khoa is the examination of packaging material, which should be neat and clean. The product should be properly protected.

b) Immediately after collecting a representative sample of khoa either by a knife or cheese trier, bring it under the nose and inhale the odour of khoa and make a mental memory of the same. Then observe the colour and appearance.Special attention should be paid to the detection of burnt particles, if any.

c) The texture of khoa is evaluated by observing the nature of plug for smoothness, cohesiveness and whether it sticks to the trier. Pressing and rolling a small piece of khoa in between the fore fingers and the thumb, note the hardness, presence of free fat, etc. Spread a small mass of khoa on the palm of your hand with the thumb and examine the uniformity, size and toughness of the grains.

d) Take a sufficient quantity of khoa in the mouth. While rolling it about in the mouth and chewing it in between the teeth, note the tactual and taste sensations.Expectorate the sample and note if any after-taste persists.

iv. Undesirable Attributes of Khoa

a) Colour and appearance defects: Too brown/dark, lack of uniformity, moist/ dry/ mouldy, surface, visible burnt/foreign particles.

b) Body and texture defects: Hard/dry, weak/loose, lack cohesiveness, grainy/ gritty and sandy texture.

c) Flavour defects: Flat, smoky, burnt, sour/acidic, metallic, rancid, oxidized, stale, salty and neutralizer.