I believe that Number of Track refers to the Number of Tracks in an Album - not the type of audio track (MP3, Digital 2.1, PCM, etc.)
Not sure of a way to do what you want to do, but I would be interested if there was a way!
It can be done if the mediainfo output of each file is parsed for the number of occurences of word "Audio #" using a script.
An example mediaInfo output of a file from my library :
General
ID : 0 (0x0)
Complete name : G:\Blu-ray Songs\Baaghi.1-Cham.Cham.m2ts
Format : BDAV
Format/Info : Blu-ray Video
File size : 1.06 GiB
Duration : 3 min 54 s
Overall bit rate mode : Variable
Overall bit rate : 38.9 Mb/s
Maximum Overall bit rate : 48.0 Mb/s
Video
ID : 4113 (0x1011)
Menu ID : 1 (0x1)
Format : AVC
Format/Info : Advanced Video Codec
Format profile : High@L4.1
Format settings : CABAC / 4 Ref Frames
Format settings, CABAC : Yes
Format settings, Reference frames : 4 frames
Codec ID : 27
Duration : 3 min 54 s
Bit rate mode : Constant
Bit rate : 35.5 Mb/s
Nominal bit rate : 28.0 Mb/s
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate : 24.000 FPS
Color space : YUV
Chroma subsampling : 4:2:0
Bit depth : 8 bits
Scan type : Progressive
Bits/(Pixel*Frame) : 0.712
Stream size : 992 MiB (91%)
Audio #1
ID : 4352 (0x1100)
Menu ID : 1 (0x1)
Format : MLP FBA AC-3 16-ch
Format/Info : Meridian Lossless Packing FBA with 16-channel presentation
Commercial name : Dolby TrueHD with Dolby Atmos
Format settings : Dolby Surround EX
Muxing mode : Stream extension
Codec ID : 131
Duration : 3 min 53 s
Bit rate mode : Variable
Bit rate : 640 kb/s
Maximum bit rate : 7 701 kb/s
Channel(s) : 8 channels
Channel layout : L R C LFE Ls Rs Lb Rb
Sampling rate : 48.0 kHz
Frame rate : 31.250 FPS (1536 SPF)
Compression mode : Lossless
Delay relative to video : 14 ms
Stream size : 17.9 MiB (2%)
Service kind : Complete Main
Number of dynamic objects : 11
Bed channel count : 1 channel
Bed channel configuration : LFE
Audio #2
ID : 4353 (0x1101)
Menu ID : 1 (0x1)
Format : AC-3
Format/Info : Audio Coding 3
Commercial name : Dolby Digital
Format settings : Dolby Surround EX
Codec ID : 129
Duration : 3 min 54 s
Bit rate mode : Constant
Bit rate : 640 kb/s
Channel(s) : 6 channels
Channel layout : L R C LFE Ls Rs
Sampling rate : 48.0 kHz
Frame rate : 31.250 FPS (1536 SPF)
Compression mode : Lossy
Delay relative to video : 14 ms
Stream size : 17.9 MiB (2%)
Service kind : Complete Main
Audio #3
ID : 4354 (0x1102)
Menu ID : 1 (0x1)
Format : AC-3
Format/Info : Audio Coding 3
Commercial name : Dolby Digital
Format settings : Dolby Surround EX
Codec ID : 129
Duration : 3 min 54 s
Bit rate mode : Constant
Bit rate : 640 kb/s
Channel(s) : 6 channels
Channel layout : L R C LFE Ls Rs
Sampling rate : 48.0 kHz
Frame rate : 31.250 FPS (1536 SPF)
Compression mode : Lossy
Delay relative to video : 14 ms
Stream size : 17.9 MiB (2%)
Service kind : Complete Main
Text
ID : 4608 (0x1200)
Menu ID : 1 (0x1)
Format : PGS
Codec ID : 144