For industrial buyers, the single most important metric dictating the commercial value of a rice lot is the Head Rice Yield (HRY). HRY, along with the Milling Degree, determines how much usable, whole grain product can be extracted from the purchased paddy (rough rice) or how much premium is justified for already-milled white rice.
Head Rice Yield (HRY)
HRY is the percentage, by weight, of whole kernels (Head Rice) obtained after the milling process. The higher the HRY, the lower the percentage of broken kernels, and the higher the value of the lot.
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Factors Influencing HRY: HRY is highly sensitive to the initial moisture content (MC) of the paddy, the variety of rice, and the efficiency and quality of the milling equipment used by the supplier.
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Contractual Use: Contracts for rough rice (paddy) should always specify a minimum guaranteed HRY, allowing for a price adjustment mechanism if the final yield falls below the agreed-upon threshold.
Milling Degree (The Polish Factor)
Milling is the process of removing the bran layer from the brown rice kernel. The Milling Degree refers to the extent of this removal (the whiteness or polish of the rice).
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Under-milled (Lightly Milled): Retains some bran, offering higher nutritional value (fiber) but a shorter shelf life and a chewier texture.
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Well-milled (Standard): Most of the bran is removed, resulting in the typical white rice texture and appearance. This is the global standard.
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Extra Well-Milled (Highly Polished): Used for specialty rice (like high-grade Sushi rice) where maximal whiteness and smoothness are desired, but this often leads to a higher percentage of broken kernels.
Buyer Specification: The required Milling Degree must be clearly specified, often by comparing the sample rice to standardized reference plates, as it affects both the appearance (color/whiteness) and the cooking performance of the final product.
Conclusion: Buyers need to balance the desired Milling Degree (for aesthetic and culinary reasons) with the crucial HRY metric (for economic yield). These specifications are foundational to any quality-driven procurement strategy.