| Congresso Brasileiro de Microbiologia 2023 | Resumo: 1112-2 | ||||
Resumo:The search for functional foods has expanded studies on probiotics, which can be defined as live microorganisms that confer benefits to human health when administered in adequate daily amounts. One of the limitations of the widespread use of probiotics in food is their viability at different storage temperatures throughout their shelf life, especially at room temperature. Thus, strategies for maintaining the viability of probiotics have been developed, including microencapsulation. This work aimed to evaluate the viability of microencapsulated Lactobacillus acidophilus by spray drying using pectin (high methoxy - HMP or low methoxy - LMP) and whey protein concentrate (WPC) during storage at room temperature (25 °C ± 1) and refrigeration (4 °C ± 1). For this purpose, microcapsules were produced with different concentrations of pectin and whey protein concentrate: F1 = 0.5:7.5 (w/w) HMP: WPC; F2 = 1:7 (w/w) LMP: WPC and F3= 0.5:7.5 (w/w) LMP: WPC by spray drying using laboratory scale equipment (SDi 1.0, Labmaq do Brasil, São José do Rio Preto, SP, Brazil), where the suspensions added with the probiotic were kept under constant agitation at room temperature and fed to the drying chamber using a peristaltic pump, under constant conditions of compressor pressure 2-4 kgf/cm-2, inlet air temperature 110 °C; flow rate: 0.40 L/min; supply flow: 0.45 L/h and air outlet diameter in the system (1 mm) with double fluid nozzle. The evaluation of the survival of the microencapsulated and free probiotic was carried out shortly after obtaining (0 days) and after 15, 30, 45, 60, and 90 days of storage in a BOD incubator with room temperature and refrigeration control, in a closed amber flask, in the presence of oxygen and absence of light, by enumeration of viable cells of L. acidophilus expressed as Log CFU/g. The results obtained were subjected to analysis of variance and, when a significant difference was detected, Tukey's test (p<0.05). When stored at refrigerated temperature, F1 preserved probiotic viability (6,70 ± 0,54 Log CFU/g) for a longer time (90 days), whereas F2 and F3 maintained viability for 60 days and the free form for 30 days. At room temperature, F2 and F3 maintained bacterial viability for 45 days (6,25 ±0,80 Log CFU/g and 6,57 ± 0,47 Log CFU/g, respectively); F1 kept viability for 30 days, while the free form had viability for less than 15 days. Regardless of the evaluated storage temperature, microencapsulation promoted increased probiotic viability compared to free cells. However, the viability of the microencapsulated probiotic was affected by the wall material: for refrigeration temperature, the best material was the one that used pectin HMP and WPC; in turn, for room temperature, it was pectin LMP and WPC. Microencapsulation by spray drying with the encapsulating agents increased the L. acidophilus viability at different storage temperatures. Palavras-chave: probiotic, shelf life, spray drying Agência de fomento:Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brazil (CAPES) - Finance Code 001; CNPq (Scientific Initiation Scholarship) | |||||