IMPACT OF DIFFERENT OHMIC HEATING PROCESSING PARAMETERS ON THE FATTY ACID PROFILE AND VOLATILE COMPOUNDS OF BLUEBERRY (VACCINIUM MYRTILLUS) ADDED DAIRY DESSERTS

Dairy desserts, besides being a highly nutritious food, has great acceptance and the incorporation of fruits, such as blueberry, can add both sensory and functional value to the product. However, pasteurization can cause deleterious effects on thermosensitive compounds causing undesired changes. In this context, the present work evaluated the effects of alternative thermal processing by Ohmic Heating (OH) under different electric fields (9.1, 7.30, 5.45, 3.64 and 1.82 V/cm) on the fatty acid profile (FAs) and volatiles compounds (VCs) of blueberry added dairy desserts, submitted to the same time-temperature profile (90ºC/3min) as conventional treatment (CT). The identification and quantification of FAs were performed in GC-MS (Agilient Technologies, 7890A-5975C), with CTC PAL sampler (SPME 120, Agilient Technologies). Retention times of chromatographic peaks compared to reference standards (Sigma FAME 37 18919-1AMP) and mass spectra with the NIST 11 library. Atherogenic and thrombogenic indices were calculated. VCs were obtained by solid phase microextraction (SPME), identified by gas chromatography (Agilent Technologies® 7890A GC) coupled to a mass spectrometer (Agilent Technologies® 5975C). The analyzes were performed in triplicate and submitted to ANOVA and Tukey's test (p≤0.05) using XLSTAT. No significant differences between samples were observed on the FAs profiles. For VCs, samples submitted to 3.64 and 5.64 V/cm presented smaller and similar values (04 compounds), while sample 7.30 V/cm presented 10, followed by sample 1.82 V/cm (8) and the CT with 7 compounds. The 9.10 V/cm sample presented the widest volatile profile with 11 compounds. Aldehyde (E)-2-hexenal, responsible for the blueberry flavor, was not identified in the sample at 1.82 V/cm, while the samples 3.64 and 5.45 V/cm were the ones with the highest area percentage of it. The results indicate that OH did not cause negative sensory impacts, when related to the fatty acids profile, formation and preservation of volatiles compounds.