Conditioning reduces kernel damage when impact shelling almonds
-
Maryam Shirmohammadi
and
John Fielke
Abstract
Almonds can be classified based on their shell characteristics from soft to hard shell varieties. The majority of Australian and Californian varieties have soft shell properties. Most Spanish almond varieties have hard shells. Although having a hard sealed shell protects the kernel from insect damage it affects their processability. Common commercial almond processing equipment simultaneously compresses and shears the almonds and this creates a high percentage of damaged kernels from the broken shell being forced into the kernel, particularly for hard shell varieties. This paper shows that for the soft shell variety ‘Nonpareil’ and the three hard shell varieties of ‘Marcona’, ‘Tarraco’ and ‘Vyro’ that conditioning by soaking in water and resting before processing improves the recovery of undamaged kernel when shelling using impact. The impacts were applied by feeding the almonds into a rotating impellor and throwing them onto a stationary outer wall. An effective conditioning process resulted in the kernel moisture content increasing from 6% to 14% for hard shell and to 11% for ‘Nonpareil’ varieties. The conditioning process was measured to reduce the amount of scratched, chipped and broken kernel, and hence increased the recovery of undamaged kernel. After shelling, the conditioned kernel needed to be dried back to a 6% moisture content to be suitable for storage. Hence, the industry would be able to increase its recovery of undamaged kernel by changing to an impact shelling process using suitably conditioned almonds.
Funding statement: This project (AL12003) has been funded by HIA using the Almond levy, voluntary contributions from industry and matched funds from the Australian Government.
Acknowledgement
Thanks to Omega Orchard, Select Harvests, Walker Flat Almonds and Almond Board of Australia for supplying almonds for testing.
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Articles in the same Issue
- Research Articles
- Effect of Cooking Conditions on Quality Characteristics of Confit Cod: Prediction by MRI
- Conditioning reduces kernel damage when impact shelling almonds
- Quality Enhancement of Tapioca Starch Gel using Sucrose and Xanthan Gum
- Characteristics of Pores as Measured by Porosimetry and Microscopy Considering Spaghetti as a Model System
- Improvement of Gel Properties of Fish Gelatin Using Gellan
- Drying Characteristics and Quality of Kiwifruit Slices with/without Osmotic Dehydration under Short- and Medium-Wave Infrared Radiation Drying
- Optimization of the Spray Drying Operating Conditions for Producing the Powder Mixture of Gum Arabic and Maltodextrin
- Modification of Konjac Glucomannan by Reduced-Pressure Radio-Frequency Air Plasma
- The Controllable Preparation, Properties and Structural Characteristics of Xylitol/Menthol Co-crystals
- Short Communications
- Effect of Maltodextrin on Physical Properties of Granulated Xanthan Gum Prepared by Fluidized-Bed Granulator
