Chemical analysis includes following tests:
i). Moisture: normally flour should have 14% moisture. Excessive moisture adversely affects the keeping quality of flour and is undesirable from an economic standpoint also.
ii.) Ash: It determines mineral matter in flour and therefore is considered as a measure of the degree of separation of the flour from a particular wheat blend but cannot be considered a reliable index of baking quality.
iii.) Proteins: this will give the quantity of proteins but for baking purpose both quantity and quality are required.
iv). Maltose and gassing power: this will indicate activities of beta and alpha amylase.
Physical Methods are those where sophisticated equipment is used for determining quality of flour. These include:
i.) Amylograph which measures alpha-amylase activity
ii). Farinograph measures strength of flour for commercial mixing operation.
iii). Extensograph indicates the loaf volume potentialities.
iv). MacMicheal viscosimeter indicates the amount of bleaching that flour has undergone. Bleaching incidentally weakens proteins.
v). PH value indicates the acidity or alkalinity.
Physical Examination will include following:
i). Pekar colour test indicates the separation.
Baking test: A standard lab-scale baking test will indicate in general way the baking qualities of a given flour, although slight difference may by noted when large commercial batches are made up in the machine-equipped bakery. Some bakers, inspite of the shortcomings in this methods, are of the opinion that actual baking test gives the best overall evaluation of the flour quality.
Water
Sources, types, Functions and Usages of water