Kl. Wiese et Er. Jackson, CHANGES IN THERMAL-PROCESS TIMES (B(B)) FOR BAKED BEANS BASED ON WATER HARDNESS AND FILL TEMPERATURE, Journal of food protection, 56(7), 1993, pp. 608-611
To compare the consequences of water hardness on canning of dry beans,
baked beans were prepared using water that contained 70 or 260 ppm ca
lcium for soaking/blanching of navy beans and in the preparation of a
tomato sauce for brine. Another factor examined for this project invol
ved increasing the initial temperature of the canned beans prior to th
ermal processing by eliminating the cooling step after blanching. In g
eneral, if the initial temperature prior to thermal processing can be
increased, the process time (B(b)) is generally decreased. However, wh
en the initial temperature of these baked beans was increased by this
method, the process time increased in comparison to the time for beans
that were cooled after blanching. In examining the water hardness, th
e beans, which had been cooled after blanching, processed with an incr
eased CaCO3 demonstrated a decreased process time (F(o) = 5.3) in comp
arison to those beans processed with a lower CaCO3. In one instance, t
he process time was decreased by 12% due to the presence of calcium po
ssibly due to decreased gelatinization, physical restriction of swelli
ng, reduced solubility of pectin, starch, and protein in the brine sol
ution; consequently, these actions would increase the heat transfer in
the food during thermal processing. Based on these investigations, wa
ter hardness should be considered an important parameter when performi
ng heat-processing determinations and in the transference of heating d
ata from one site to another.