VITAMIN A FORTIFIed PEANUT BUTTER - The Official Website of ...

On the other hand, fortified peanut butter in the 80 Kg production batch showed acceptable
vitamin A recoveries of 95.8 and 79.9% for the 1 st and 2 nd production batches, respectively. For the 100
Kg production batch, the fortified peanut butter had a slightly lower vitamin A recovery of 73.8% as
compared to the 79.9 – 95.8% recovery obtained in the 80 Kg production batch but the recovery was still
considered acceptable.
Considering the relatively high vitamin A recovery and uniform dispersion of the premix in the
final product in the 80 Kg production batch, this was recommended as the appropriate fill-volume of the
horizontal mixer of the industry collaborator, for the commercial production of fortified peanut butter.
Experiment 5: Determination of the effect on vitamin A recovery using premix prepared from
two different types of mixers for the commercial production of fortified peanut butter
Tables 2.8 and 2.9 show the effect of using premix prepared from the horizontal mixer and
Hobart planetary mixer of the industry collaborator on vitamin A recovery in the final fortified product.
Fortified peanut butter prepared using premix from the horizontal mixer showed acceptable vitamin A
recoveries ranging from an average of 80.7% to 85.0% with low percentage variability that ranged from
1.83 – 9.95%. Above data indicates uniform dispersion of the premix in the final fortified product. Above
data confirms suitability of the horizontal mixer of the industry collaborator for the preparation of
fortified peanut butter.
On the other hand, vitamin A recovery in the final fortified product using premix prepared from
the Hobart planetary mixer showed low vitamin A recoveries (39.1, 35.3 and 35.6%). This was the case
even if vitamin A recovery in the premix using the Hobart planetary mixer was good (Table 2.6). The
low vitamin A recoveries in the final fortified product using premix prepared from the Hobart planetary
mixer of the collaborator was attributed to the possible incorporation of too much air in the premix
causing the vitamin A to oxidize when subjected to further mixing during the final fortification step. A
comparison of the mixing action of the industry collaborator’s horizontal mixer and Hobart planetary
mixer showed that the two equipment exhibited a different manner of mixing the product. In the Hobart
planetary mixer, mixing of the product was accomplished by an agitator that was mounted on top of the
mixing vessel in a vertical off center position. This was observed to move in a planetary motion, i.e. as
the agitator rotates on its axis in circular strokes, it repeatedly moves around the mixing vessel at a fast
speed. This type of mixing creates a vortex owing to the centrifugal force acting on the product. As there
is a limit to the rotational speed of an equipment, there is a tendency for a severe entrapment of air to
occur once the vortex reaches the agitator (Perry and Chilton, 1973). With the horizontal mixer, the
agitator was mounted horizontally near the bottom of the mixing vessel. Mixing was accomplished as the
stationary blade rotated on its axis providing large circular strokes at a relatively low to medium rate. The
circulatory strokes cause the product to flow in the direction of motion of the agitator causing the relative
velocity between the blades and the product to be reduced.
Reducing the mixing time of premix production to five minutes with the Hobart planetary mixer
of the industry collaborator increased vitamin A recovery to 57% (from a low of 35.3%, see Trial Batch
2). This data supports the above hypothesis that the low vitamin A recovery in fortified peanut butter
using premix prepared from the industry collaborators’ Hobart planetary mixer, was due to the
incorporation of too much air in the premix. It will be noted that low vitamin A recoveries in premix
preparation was not experienced in the use of the Hobart vertical mixer Model HCM 300 as the said
mixer, unlike that of the industry collaborator did not rotate in a planetary motion. Based on the above
findings, it was found that the type of mixer used for premix preparation affected vitamin A recovery in
the final fortified product.
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