Influence of Nut Cracking Methods on Kernel Quality and Separability of Product
Abstract
In order to provide rational basis for design considerations to reduce kernel breakage in palm nut cracking using the conventional centrifugal nutcracker and enhance subsequent kernel and shell separation, comparison was made between the qualities of products from manually and mechanically cracked nuts. Furthermore, a 23 factorial experiment was conducted to determine the effects of the machine operational parameters and size of nut on nut cracking efficiency, quality of recovered kernels, and fragmentation of the nutshell. The nutcracker with a throughput capacity of 250 kg/h and a rotational of 1100 rpm gave a cracking efficiency of 97.2%, but kernel breakage was up to 9.7%; however, kernel breakage was 5.5% when the nutcracker was driven at a lower speed of 800 rpm and unbroken nuts were recycled. In contrast, cracking the nuts manually yielded 100% cracking efficiency and 2.0% kernel breakage, but the process was cumbersome and time consuming. In relation to the separation of the product, shell particles passing through a sieve with 10 mm aperture were 71.3% of the total shell produced using the nutcracker; compared with 58.3% from nuts broken manually.
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