Apple snack enriched with L-arginine using vacuum impregnation/ohmic heating technology

Functional food development has gained attention due to increasing consumer demand for health-promoting products. Prior research has shown that vacuum impregnation can enhance nutrient content in fruits. However, no prior work had resolved the most effective method to enrich amino acids in dried apple snacks. This gap motivated the investigation of vacuum impregnation combined with ohmic heating. Established knowledge includes the role of L-arginine in cardiovascular health. This paper's contribution is evaluating thermal treatments for L-arginine enrichment. It was already known that vacuum impregnation increases water absorption. That uncertainty drove the study of temperature effects on impregnation efficiency. No prior work had resolved the optimal drying temperature for preserving L-arginine content.

The aim was to evaluate methods for enriching L-arginine in apple snacks. This paper addresses the challenge of functional food production using emerging technologies. The specific problem is how to maximize L-arginine retention during processing. Motivation comes from the need for semi-essential amino acid enrichment in fruit-based snacks. The study compares vacuum impregnation with and without ohmic heating. It also examines the impact of temperature on impregnation kinetics. The goal is to identify a process that preserves L-arginine content. The study focuses on vacuum impregnation/ohmic heating at 50 ℃ as a key treatment. This approach allows for controlled nutrient delivery into fruit matrices.

The study used vacuum impregnation to introduce L-arginine into apple cubes. Conventional heating and ohmic heating were tested at 30, 40, and 50 ℃. Vacuum impregnation was combined with both heating methods. Impregnation kinetics were measured to assess L-arginine uptake. Sample color was evaluated as a quality indicator. Air-drying at 40 ℃ followed impregnation treatments. The study compared impregnation efficiency across temperature levels. Electropermeabilization effects were considered in ohmic heating treatments. The process involved sequential vacuum and thermal steps to maximize nutrient retention.

Vacuum impregnation/ohmic heating at 50 ℃ achieved the highest L-arginine content. This treatment resulted in 2.5-fold higher enrichment than conventional methods. Electropermeabilization was identified as a key mechanism in this process. Color changes were minimal in samples processed at 50 ℃. Drying at 40 ℃ preserved L-arginine content without significant degradation. Impregnation kinetics showed faster uptake at higher temperatures. The study found no significant difference in L-arginine content at 30 ℃. Vacuum impregnation alone did not match the efficiency of combined treatments.

The authors propose that vacuum impregnation/ohmic heating at 50 ℃ is optimal for L-arginine enrichment. This treatment maximizes nutrient content while preserving snack quality. The study suggests electropermeabilization enhances impregnation efficiency. Drying at 40 ℃ was found to maintain L-arginine levels effectively. The authors state that this process is preferable to conventional heating methods. They propose that higher temperatures improve impregnation kinetics. The findings suggest that combined treatments outperform single-step approaches. The authors conclude that this method can be applied to functional food production.