**2. Postharvest handling practices**

#### **2.1 Harvest operations**

The yield of pods stabilizes about 15 years and can last up to 50 or 60 years. When tamarind fruits are finger pressed, a hollow and loose sound is generated, indicating that the pulp has shrunk with maturity and the fruit is ready for harvesting. Brittleness develops in the shell. Additionally, a change in testa color could signify matured fruit of the tree [3]. Individual fruits on the same tree mature at different periods, making it difficult to select the right one for which harvesting is required. Pods are picked at various stages of ripeness, depending on their intended purpose. The sour tamarind mature fruits are commonly sold in most nations. It can be obtained by shaking trees and gathering up fallen fruits. The fruits are usually allowed to ripe on the tree before being harvested, reducing the moisture content to around 20% [4]. If left unharvested, the pods can stay on the tree for over a year after flowering, and will inevitably descend. Fruits for immediate processing are frequently harvested by separating the pod from the stalk, leaving longitudinal fibers connected. Fungi and beetles in humid conditions, ripe fruit is more easily attacked, thus they should be harvested before they have reached full ripeness.

Trunk shakers and branch shakers are the few mechanical advancements in harvesting fruit bunches. Trunk shakers are best suited for trees that have soft trunks and branch shakers are best suited for trees that have hard trunks like tamarind. Nowadays, branch shakers are available at a 2.5 kW power level. A twostroke petrol engine drives the shaker. This commercial branch shaker is similar to a brush cutter with a 2 m long hooked pipe at the end to hold the branches intact and the reciprocal action of the engine imitates the shaking action [5].

### **3. Engineering properties of tamarind**

The understanding of physical and mechanical qualities aids in the analysis of its behavior during handling and the design of process equipment. The average value of properties such as moisture content, size, shape, bulk density, true density,

porosity, angle of repose, surface area, and coefficient of friction was determined for whole and dehulled tamarind (**Table 1**) [6].
