Why is oven drying of samples generally discouraged?

Oven drying of samples is generally discouraged primarily because it affects nutrient analytical results. This method of drying can lead to the degradation or alteration of certain nutrients within the sample, potentially skewing the analytical data obtained from subsequent tests. For example, high temperatures can cause the volatility of some minerals or the destruction of organic compounds, which are crucial for accurate nutrient analysis. Therefore, using methods that preserve the integrity of the nutrients is preferable when preparing samples for analysis.

The other considerations surrounding oven drying—such as increased moisture content, damage to the physical structure of the sample, and reduction in sample size—are relevant but secondary to the impact that oven drying has on nutrient stability and availability for analysis. Thus, the primary concern remains the accuracy of nutrient analytical results, making this consideration paramount in decision-making for sample preparation.