A low-fat synbiotic cream cheese containing herbal gums, Bifidobacterium adolescentis and Lactobacillus rhamnosus: Physicochemical, rheological, sensory, and microstructural characterization during storage.

This study aimed to use natural herbal gums, as fat replacers, for preparing a low-fat synbiotic cream cheese; for this purpose, the effects of Lepidium perfoliatum seed gum (LPSG) (1% w/w) and flaxseed gum (FG) (1% w/w) on physicochemical, rheological, organoleptic, and microstructural properties of low-fat cream cheese containing B. adolescentis and L. rhamnosus were analyzed over a 45-day storage period. The results indicated that adding LPSG and FG had no significant effects on acidity and pH (p > .05). The results also showed that full-fat (FF) cheese samples had the highest textural (hardness (1.099-0.88), cohesiveness (0.72-0.67), springiness (1.95-1.64), adhesiveness (1.01-0.69), and spreadability (1.53-1.17)), viscosity and sensory scores (color (4.22-4.18), odor (4.13-4.09), taste (4.19-3.89), texture (4.08-3.81), and overall acceptability (4.01-3.72)) during 45-day storage. Based on the probiotic count test, only the treated samples with LPSG + FG had a probiotic count in the standard range (6.23 cfu/g) at the end of the storage time. The outcomes of the present study indicated that the incorporation of LPSG and FG into the formulation of low-fat synbiotic cream cheese could be an effective strategy to overcome the problems associated with fat reduction.

Combined effects of ε-polylysine and ε-polylysine nanoparticles with plant extracts on the shelf life and quality characteristics of nitrite-free frankfurter-type sausages.

In this study, ɛ-polylysine (ɛ-PL) or ɛ-polylysine nanoparticle (ɛ-PLN) combined with plants extracts (including green tea, olive leaves and stinging nettle extracts) were used as nitrite replacers in frankfurter-type sausages. The sausage samples were wrapped in polyethylene bags (in vacuum conditions) and their physicochemical, microbiological and sensory properties were evaluated during 45 days of refrigerated storage. The results showed that the incorporation of ɛ-polylysine had no significant effects on proximate composition of sausages. However, ɛ-PL and ɛ-PLN sausages had significantly (P < 0.05) lower lightness, redness and higher yellowness compared to control samples. At the end of storage, sausages formulated with ɛ-PLN had significantly (P < 0.05) higher contents of phenolic compounds and lowest TBARS values. Microbiological counts also indicated that ɛ-PLN displayed significantly higher inhibitory effects. Higher sensory indices were obtained in ɛ-PLN sausages. Based on the obtained results, ɛ-PLN was effective to improve frankfurter-type sausages shelf life. Therefore, these ingredients could be useful for frankfurter-type sausages production as nitrite replacers.

Effects of osmotic dehydration (with and without sonication) and pectin-based coating pretreatments on functional properties and color of hot-air dried apricot cubes.

The objective of this study was to investigate the effect of osmotic dehydration (with and without sonication) and the use of different types of edible coating on functional and color parameters of dried apricot. Osmotic pretreatment was carried out in sorbitol solution of 35 °Brix at 55 °C for 30 and 45 min. Two levels of ultrasound frequency (25 and 35 kHz) were tested. Samples were coated using pectin + citric acid (CA), pectin + ascorbic acid (AA) and pectin alone after osmotic treatment and were dried at 60 °C. The results revealed that ultrasound assisted osmotic dehydration (UOD) led to the loss of total phenolic compounds (TPC) and vitamin C compared to osmotic dehydration (OD). TPC and ß-carotene contents decreased with the increase in sonication frequency from 25 to 35 kHz. However, UOD pretreated samples showed higher antioxidant capacity and ß-carotene content than OD apricots. OD improved color of hot-air dried apricot compared to UOD pretreatment. The use of pectin + AA coating increased TPC and vitamin C retention and total antioxidant activity of OD or UOD pretreated samples compared to pectin or pectin + CA coatings. UOD and pectin + AA coated samples showed lower L* and b*, and higher a* values, whereas coating with CA improved color of dried apricot cubes. Coatings containing CA or AA promoted ß-carotene retention in dried apricot pretreated by OD and UOD.

Combined effect of natural antioxidants and antimicrobial compounds during refrigerated storage of nitrite-free frankfurter-type sausage.

The effects of nisin (200 and 400 ppm), ε-polylysine (0.1 and 0.2%) and chitosan (0.5 and 1%) in combination with a Mixed Extract (green tea, stinging nettle and olive leaves extracts) on the physicochemical, microbiological characteristics, fatty acid composition and sensory attributes of the nitrite-free frankfurter-type sausages were assessed during 45 days of storage. The results revealed no significant differences on moisture, fat, protein, ash, salt and water activity (aw) among treatments. 1% Chitosan + Mixed Extract sausages displayed the lowest thiobarbituric acid reactive substances (TBARS) and total volatile nitrogen (TVN) values compared to Control after 45 days of refrigerated storage. Combinations of 0.2% ε-Polylysine or 1% Chitosan with Mixed Extract were effective to inhibit total viable count (TVC), yeasts and molds growth. 1% Chitosan preserved the luminosity of sausages during refrigerated storage. However, redness values of 1% Chitosan treatment was lower than those obtained from Control sausages and a significant increase was observed between days 30-45. Total amounts of saturated, monounsaturated and polyunsaturated fatty acids (SFA, MUFA, and PUFA) of frankfurter-type sausages were not largely influenced by the combination of natural antioxidants and antimicrobial compounds. Combinations of 0.2% ε-Polylysine and 1% Chitosan with Mixed Extract were effective to improve the shelf life of nitrite-free frankfurter-type sausages. Therefore, these combinations could be considered as promising nitrite replacer in frankfurter-type sausages.

Use of gelatin and gum Arabic for encapsulation of black raspberry anthocyanins by complex coacervation.

Protein-polysaccharide interactions offer opportunities for designing the new functional foods with applications in the food and pharmaceutical industries. In this work, we microencapsulated black raspberry water extracts by double emulsion technique prior to complex coacervation using gelatin and gum Arabic to diminish the instability of their anthocyanins (ANCs) as water soluble compounds, particularly under harsh processing and storage conditions. Subsequently, optical microscopy, moisture, hygroscopicity, solubility, particle size, loading capacity, zeta potential, color parameters (L*, a*, b*, C, H° and TCD), stability, Fourier transform infrared spectroscopy (FTIR), and thermal behavior were evaluated. The microcapsules presented the lower moisture, hygroscopicity and solubility values as comparing the free form of ANCs. They showed the average sizes ranging from 35.34±3.21 to 80.22±5.21µm and high loading capacity (29.67±0.66-38.54±0.08%). According to the HPLC results, the selected method significantly increased the stability of ANCs up to 23.66% after 2 months of storage at 37±2°C. FT-IR spectra confirmed the negative zeta potential values of microcapsules and the occurrence of coacervation process. DSC results evidenced the thermostability of microcapsules. Furthermore, the selected optimal microcapsules revealed intense red color over the time of storage, implying the effectiveness of the method chosen to preserve anthocyanins.