PurposeThe purpose of this paper is to evaluate the chemical and functional composition of acerola, guava and cashew freeze-dried pomaces.Design/methodology/approachFruit pomaces were obtained from the pulp juice industrial sector and submitted to freeze-drying. Samples were analysed for composition (macronutrients, micronutrients, moisture and ash), technological attributes (morphological, hygroscopicity, retention of oil and water and solubility), bioactive compounds (total phenolics, flavonoids, proanthocyanins, anthocyanins, carotenoids and ascorbic acid), antioxidant and antimicrobial properties. Total phenolics, brown pigments and antioxidant activity of thermally treated samples were evaluated. Results were presented as mean and standard deviation, and submitted to Shapiro–Wilk normality test, and ANOVA statistical significance follows by Tukey’s post hoc test (p<0.05). Also, Pearson correlation coefficients were used to test the relationship between selected parameters.FindingsGuava pomace had the highest insoluble fibre (40.6 per cent), protein (13.8 per cent) and lipid (9.3 per cent) contents and acerola higher soluble fibre (14.2 per cent) and water and oil holding capacity (12 and 5.4 g/g, respectively). Cashew pomace had higher solubility (45.3 per cent) and hygroscopicity (11.2 per cent). Acerola pomace had the highest phenolic content (5,331.7 mg AGE/100 g), DPPH and oxygen radical absorbance capacity antioxidant activity (63.3 and 756.6 µmol TE/g). Despite of that none of extracts showed antibacterial activity. All pomaces presented good antioxidant activity retention after thermal treatments (> 70 per cent), which might be correlated to thermally induced brown pigments.Originality/valueThis investigation was motivated by the large amounts of pomaces produced by the fruit pulp and juice processing industries, which represents a waste of residual phytochemicals and cause potential environmental problems. Overall, it was demonstrated that freeze-dried acerola, guava and cashew pomaces are promising ingredients for multiple food applications.

Fruits agro-industrial by-products may have a great variety of bioactive compounds that promote health. Thus, the effects of supplementation with acerola, cashew and guava processing by-products for 28 days on retinol level, lipid profile and on some aspects related to intestinal function in rats were investigated. The animals supplemented with different fruit by-products presented similar weight gain, faecal pH values and intestinal epithelial structures; however, they showed higher moisture and Lactobacillus spp. and Bifidobacterium spp. counts in faeces compared to the control group. Supplementation with the cashew by-product decreased the blood glucose, acerola and guava by-products reduced serum lipid levels and all fruit by-products tested increased serum and hepatic retinol. The results indicated that acerola and guava byproducts possess a potential hypolipidemic effect. The three fruit by-products increase the hepatic retinol deposition and the faecal populations of beneficial bacterial groups and modulated aspects of intestinal function. The findings of this study can contribute to sustainable fruticulture and support future clinical studies with the supplementation of by-products.