Food & Process Engineering Technology
ERRATA (March 2006)
L.R. Wilhelm, D.A. Suter, G.H. Brusewitz
ISBN: 1-892769-43-3
Page 14. The second equation is repeated. Delete repeated equation.
Page 15. The fifth equation from the bottom should be: 0.27 S = 16.
The remaining equations then become:
S = 59.26
C = 0.5 S = 0.5 (59.26) = 29.63
P = 100 – 1.5 S = 100 – 1.5 (59.26) = 11.11
S + C + P = 59.26 + 29.63 + 11.11 = 100
Page 19, Problem 1.1. Item j should be 9.008 × 104.
Page 27, Figure 2.01. The title under the upper left image should be Roundness = Ap/Ac
and the title under the lower left image should be Roundness Ratio = r/R.
Page 41, Figure 2.07. The legend on the Y axis should show units of kJ/(kg K).
Page 51. Suggested alternate or additional problems:
2.4. Name two fruit/vegetables that are good examples of:
(a) having nearly round shape and (b) having elliptical shape.
2.5. Compute the roundness of a square object having sides 1.0 cm long.
2.7. Compute the sphericity of a cube having 1.0 cm sides.
Page 52, Problem 2.30.b. The temperature should be 70°C (not 20°C).
Page 55, Figure 3.01, Torsion. Clarification: the arrows show the ends of the rod being
twisted in opposite directions.
2
Page 97. Equation 4.27 should be:
2
Pt1  N1   D1  ρ1

 
=
Pt 2  N 2   D2  ρ 2
(rho instead of P)
Page 108, Problem 4.1. Units for the velocity squared term should be ft2/s2.
Page 117. In Equation 5.07, a plus sign is missing between the terms LinsRins and Lp2Rp2.
The equation should be: Rt = Ri + L p1R p1 + Lins Rins + L p 2 R p 2 + Ro .
Page 139, Problem 5.9. The sheathing is medium density particleboard.
Page 145. In the second equation from the bottom, a minus sign is missing from the second
and third terms of the equation. It should be:
 − 10 × 0.007854 × 600 
 − 47.12 
 = exp
= exp
 = exp(− 0.2099) = 0.8107
8954
×
0
.
00006545
×
383
.
1
 224.5 


Page 152. In line 4, Lo = 0.0555 m. This requires correction of the first and third equations on
that page. This correction results in the following changes in calculated parameters on that
page: Fop = 0.2024; Bip = 43.4; Tp = 0.785; T = 0.156; tc =112.2°C.
Page 152. In the third line from the bottom, the reference should be to Example 6.3 (not 6.1).
Page 153. In the second equation, the value of ro in the equation should be 0.05 m (not 10 m)
giving a value of Bi = 1.17.
The next sentence should then be: Using Figure 6.07 at T = 0.2 and Bi = 1.17, we find Fo =
0.72. (Delete the note that follows.)
The equation for θ should be corrected for Fo and ro and the final result is:
Thus, θ = 10 500 s = 175 min = 2.92 hours
Page 158, Figure 6.07. Vertical grid lines for 0.7 and 5 are missing. Corrected figure is below.
Page 159, Figure 6.08. Vertical grid lines for 0.04, 0.1, 0.2, 0.3 and 80 are missing. Corrected
figure is below.
Page 161, Problem 6.1. Units for k should be W/m K (not W/m k).
Page 161, Problem 6.3. Time should be in minutes (not seconds).
Page 191, Problem 7.4. Assume a come-up-time of 10 minutes for all four processes.
Page 204, Line 4. The equation should show units of m3 (not m3). Thus it should be:
FT = 262 500 kJ/m3 [0.000 100 m3 K/W + 0.000 008 9 m3 K/W]/20 K.
Page 235, Figure 9.05: hsf = 335 kJ/kg (not 3.35).
Page 263, Table 10.01. Pumpkin seed data are for pumpkin seed kernels.
Page 264, Example 10.2. Remove the extra right parenthesis following ERH in the first term.
ln (1 − ERH )
It should be: M e = N
− K (t + C )
Page 301, Table A.8. Units for Heat of Respiration are mW/kg.
1.0
Each curve represents
the Biot num ber
Dimensionless Temperature (T)
0.9
0.8
4.0
0.7
1 000 000
0.6
2.0
0.5
100
0.4
20
0.3
0.2
1.0
6.0
0.1
0.2
0.8
0.7
0.3
1.0
0.6
0.5
0.6
0.4
0.4
0.3
0.06
0.2
0.1
Sphere
Sphere
0.0
0.01
Each curve represents
the Biot number shown
0.9
Dimensionless Temperature (T)
1.0
0.1
1
10
Fourier Modulus (Fo)
Figure 6.07. Dimensionless center temperature
for a sphere (high Biot number).
0.0
0.01
0.1
1
10
Fourier Modulus (Fo)
Figure 6.08. Dimensionless center temperature
for a sphere (medium Biot number).
100