Preparation of Rabri

i.Traditional Method

Traditionally rabri is prepared from milk by private traders (Halwais) at a very small scale by simmering whole milk for a prolonged period and adding sugar after achieving the desired concentration. The manufacture of rabri, in fact, started by halwais (tea walla) who sit in small localities and sell milk in small lots to the nearby residents. They keep the milk in hot condition (near to boiling temperature) in a shallow karahi with heavy bottom to avoid spoilage. The formation of a thin skin(malai) on the hot milk and air interface repeatedly takes place in this undisturbed condition. When a customer comes to buy milk, halwai removes malai from the surface with a ladle to the cooler side of the karahi and sell the bottom portion of milk. This practice is continued for a long time (several hours). When the amount of milk is considerably reduced, it is boiled and concentrated to about 3-4 folds. Then sugar is added and finally the malai, which was collected on cooler side of the karahi is remixed with concentrated sweetened milk. This product is sold at an exorbitant price. Since the process is time consuming and labour and energy intensive,a very few halwais prefer to prepare rabri. Rabri prepared in this way is stored in open and shallow type of container, which leads to enormous contamination from surroundings. Because of lack of refrigeration facilities and very high cost of raw milk during summer months, many halwais refrain from preparing rabri during this season resulting in very high cost.

  

ii.Improved Method of Rabri Making

The consumers are increasingly becoming conscious about the quality and safety of milk based sweets. This awareness is influencing the consumer to purchase the products from the organized establishments even at higher price. These facts underline the need for standardization and mechanization of rabri to produce high and uniform quality product at large scale and to reduce the post manufacturing contamination(Fig).

Flow diagram of a improved method of rabri making

Buffalo milk is preferred for preparation of rabri because it contains higher fat content that is responsible for the formation of a thick layer of malai. Steam heating of milk is recommended because it will enable better control of temperature and prevent development of flavour defects, like smoky and burnt. After adding malai to sweetened concentrated milk, the flavouring ingredients (cardamom) and dry fruits(almond, cashew nut etc.) can be added. Rabri prepared by this method should be immediately chilled and packaged under hygienic conditions to prevent post- manufacturing contamination.

 

iii. Large Scale method of rabri making

Scraped surface heat exchangers (SSHE) are presently used for the continuous manufacture of khoa. Since rabri is also a heat-desiccated product like khoa, though to lesser extent, SSHE can be used for pre-concentration of milk to the solids level as of rabri. The flaky texture, which is an integral and desirable attribute of rabri and produced by adding malai, can be simulated by incorporating similar fibrous and flaky material in from of shredded chhana/paneer to this concentrated milk. The method developed on this concept has been shown in flow diagram (Fig).

Flow diagram of a large-scale method for preparation of rabri