460 Chapter 17
given in Table 17.20. Figure 17.9 shows the
general steps for the manufacture of shelf -
stable and extended shelf - life refrigerated
pudding.
The sterilized pudding process requires
more rigorous heat treatment (Chambers and
Nelson, 1993 ). Direct heating systems use
live stem injection or infusion into the
product. The ultra - high temperature (UHT)
processing is conducted in appropriate equip-
ment to accommodate increases in viscosity
during heat treatment of the mix. It is common
to subject the mix to a preheating tempera-
ture range of approximately 49 ° C (120 ° F). In
the subsequent step, the preheated mix enters
the UHT system where the temperature is
raised to 135 ° C to 148.9 ° C (275 ° F to 300 ° F).
The mix then enters a holding tube where it
is held for the appropriate time (2 to 3
seconds) to ensure cooking of the pudding
and effective microbial kill to achieve steril-
ity of the product. Thereafter, the cooked
pudding is cooled to a temperature range of
26 ° C to 30 ° C (79 ° F to 86 ° F) and stored in an
aseptic vessel followed by packaging in an
aseptic environment.
Pudding may be processed without the
use of a scraped surface heat exchanger if
the viscosity remains relatively low after
aseptic heat treatment (Joseph et al., 1988 ).
Such a product is formulated by using 73.2%
skim milk, 17.43% sucrose, a low starch
level (2.8% modifi ed waxy maize starch),
5.62% vegetable fat containing hydrogenatedscraped - surface heat exchanger (SSHE). A
converted ice cream freezer (without the
cooling system) also has been used by con-
necting a steam supply in the jacket. The
temperature of the product is raised to 90.6 ° C
to 93.3 ° C (195 ° F to 200 ° F) with steam
pressure.
The product is then run from the SSHE to
the hopper of the packaging assembly via a
holding tube so that temperature of the pack-
aged product in the cup is 73.9 ° C (165 ° F).
The lids are applied and the cups are inverted
in the wire cases. Adequate interspaces are
allowed for proper cooling and the cups are
held at room temperature for 10 to 15 minutes
for pasteurization of the interior of the cup
and lid before cooling. They are then trans-
ferred to a freezer at − 22 ° C ( − 8 ° F) to cool
the product to 10 ° C (50 ° F). To facilitate
cooling within an hour, it is essential to blow
cold air onto the cases. After the product is
at 10 ° C (50 ° F), the wire cases are held at a
temperature below 7 ° C (below 45 ° F) over-
night before the cups are transferred to ship-
ping cases. The product is released for
shipment if it meets the standards. The shelf
life of this pudding is 45 to 60 days at 5 ° C to
7 ° C (41 ° F to 45 ° F).
Sterilized and Aseptically Packaged
Starch - based Milk Pudding
A suggested formula for sterilized and asepti-
cally packaged starch - based milk pudding is
Table 17.19. Formulation for 1,000 - pound batch of refrigerated
dairy pudding.
Ingredient Pounds
Vanilla Light
chocolateDark
chocolate
Whole milk 750 732 726
Cream, 40% fat 25 25 25
Nonfat dry milk, low heat 18 13 13
Sucrose 148 160 160
Modifi ed starches 58 57 51
Flavor and color As needed 0 0
Cocoa 0 14 25
Adapted from Chandan (1997)