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Acrylamide is a chemical naturally formed in certain foods during processing and/or cooking at high temperatures. Scientific studies have indicated that significant dietary exposure to acrylamide poses a risk for several types of cancer and may have harmful effects to the nervous system in humans. Hence, methods that can contribute to reduce acrylamide exposure in foods are needed. Considering that specific lactic acid bacteria are able to remove a variety of foodborne mutagens, namely heterocyclic amines, lead, cadmium and aflatoxin B1 by a binding mechanism, the aim of the present study was to assess the ability of fourteen lactic acid strains to remove acrylamide in vitro. Acrylamide binding ability ranged from 11.89 to 29.12%, and it was found to be both concentration‐ and strain‐dependent. Lactobacillus reuteri Northern Regional Research Laboratory 14171 (USDA‐ARS) and Lactobacillus casei Shirota were the most efficient binders (24.01 and 24.95%, respectively) after 12 h of incubation using an acrylamide concentration of 5 μg/mL. Acrylamide binding was also pH‐dependent, and the bacterial–toxin complex exhibited high stability assessed by repeated washings. The results of this work proposes for the first time the acrylamide binding ability in vitro of selected lactic acid bacteria, which suggest their potential for detoxification of the food contaminant acrylamide. Practical Applications All bacteria tested proved capable to bind acrylamide efficiently and rapidly in phosphate buffer saline; hence, these bacteria could be an effective decontamination mechanism against foodborne acrylamide along the gastrointestinal tract. It is reasonable to believe that during the first contact of acrylamide‐contaminated food with lactic acid bacteria in the mouth, the place where digestion starts and the pH is favorable for the toxin–bacteria interaction, a portion of acrylamide may be bound by the bacteria. Moreover, as both toxin and bacteria navigate through the digestive tract, the variations in pH may cause mutagen binding at different extents until it reaches the small intestine (alkaline pH), the site where absorption of food components is the highest, and the pH value is favorable. Therefore, this kind of bacteria could play a protective role by reducing the bioavailability of foodborne acrylamide.

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Phospholipids are a biologically and industrially important class of compounds whose physical properties can be improved for diverse applications by substitution of medium-chain fatty acids for their native fatty acid chains. In this study, phosphatidylcholine (PC) was enriched with medium-chain fatty acids (MCFAs) by acidolysis with phospholipase A(1) (PLA(1) ) immobilized on Duolite A568. Response surface methodology was employed to evaluate the effects of the molar ratio of substrates (PC to free MCFAs), enzyme loading, and reaction temperature on the incorporation of free MCFAs into PC and on PC recovery. Enzyme loading and molar ratio of substrates contributed positively, but temperature negatively, to the incorporation of free MCFAs into PC. Increases in enzyme loading and the molar ratio of PC to free MCFAs led to increased incorporation of the latter into the former, but increased temperature had the opposite effect. By contrast, an increase in enzyme loading led to decreased PC recovery. Increased temperature had also a negative effect on PC recovery. Optimal conditions for maximum incorporation and PC recovery were molar ratio of PC to free MCFAs of 1:16, enzyme loading of 16%, and 50°C. Under these conditions, the incorporation of free MCFAs was 41% and the PC recovery was 53%.

Bioactive compounds such as ω-3 fatty acids and terpenes, have been associated with beneficial health effects; however, their solubility in the gastrointestinal tract and its bioavailability in the body are low. Nanoemulsions offer a viable alternative to disperse lipophilic compounds and improve their dissolution, permeation, absorption and bioavailability. Enzyme modified phosphatidylcholine (PC) with ω-3 fatty acids was used as emulsifier to stabilize oil-in-water nanoemulsions generated using ultrasound device. These systems were used as carriers of betulinic acid, which has reported anti-carcinogenic activity. Phospholipase-catalyzed modification of PC allowed the incorporation of 50 mol% of ω-3 fatty acids. Formation variables such as oil type and ultrasound amplitude had effects on nanoemulsion characteristics. Incorporation of betulinic acid affected globule size; however, betulinic acid nanoemulsions below 200 nm could be prepared. The conditions under which betulinic acid nanoemulsions were obtained using the modified phosphatidylcholine with the smaller globule size (91 nm) were 10% PC, 25% glycerol, medium chain oil and 30% amplitude for 12 min in the sonicator. Storage temperature had an effect on the stability of the nanoemulsions, at 5°C we observed the smallest growth in globule size. The use of olive oil decreased the globule size growth during storage of the nanoemulsion stabilized with modified phosphatidylcholine, although globule size obtained was greater than 200 nm. Medium pH had a significant effect on the nanoemulsions; alkaline pH values improved storage stability. These results provide useful information for using this type of carrier system on the formulation of products in the pharmaceutical or food industry.