Influence of stingless bee genus (Scaptotrigona and Melipona) on the mineral content, physicochemical and microbiological properties of honey.

Stingless bees, important pollinating insects in the tropics, produce honey whose unique quality features differentiate their origin. The feasibility of multivariate data analysis for quality discrimination of stingless bee honey from different genera (Melipona bicolor, quadrifasciata, marginata and Scaptotrigona bipunctata) by mineral content, physicochemical and microbiological properties were investigated. The principal component analysis explained 72.12% of the total variance of the data, and the separation into two main groups in a scatter plot was observed. Group 2 was formed by Scaptotrigona genus, that showed the highest values of pH, ash, and soluble solids. Potassium was the most abundant mineral followed by calcium and sodium for both groups quantified by inductively coupled plasma optical emission spectrometry. This honey has higher acidity and moisture than Apis mellifera honey. Microbiological analyses showed that total aerobic mesophiles ranged between 2.00 and 4.77 log CFU/g. Salmonella spp. was not detected, while the mould and yeast content was above the maximum allowed under the Apis mellifera honey legislation. The evaluated honey samples presented the lactic acid bacteria, which are considered a benefit. The multivariate statistical analysis was efficient in discriminate stingless bee honey, contributing to approaches that can be used for standardization and regulation.

Gluten-free baked foods with extended shelf-life.

The objective of this study was to develop a formulation that can retard staling/retrogradation of cheese breads without compromising their texture and expansion properties. During baking the dough expands and becomes soft, with lower density. Binary mixtures of cassava starch (Native + Oxidized) and with guar gum (Oxidized + Guar Gum) as well as a ternary mixture (Native + Oxidized + Guar Gum) were prepared. The mixtures were analyzed for freeze-thaw stability, expansion, pasting, thermal structural and retrogradation properties. The results were compared with those of sour cassava starch (polvilho azedo-PA), native cassava starch (N) and oxidized cassava starch (O). Moreover, cheese breads were prepared with these mixtures and evaluated during storage. The ternary mixture N + O + GG showed superior freeze-thaw stability (syneresis of 4.9, 7.8 and 11.0% in 1st, 2nd and 3rd cycles, respectively); the low retrogradation of this sample was confirmed both by DSC and FTIR analyses. The sample N + O + GG had a high expansion (> 10 mL/g) and the cheese breads developed with this mixture had a slower staling. Our results confirmed that the mixture N + O + GG can improve formulations of gluten-free baked foods.

The physicochemical and structural properties and in vitro digestibility of pea starch isolated from flour ground by milling and air classification.

The fine, coarse and parent starches were isolated from pea flour by milling and air-classification. Their structural, thermal, physicochemical properties and in vitro digestibility were investigated. Particle Size Distribution showed the fine starch with the smallest unimodal distribution (18.33 and 19.02 µm) displayed higher degree of short-range molecular order and lower number of double helix structure. Scanning Electron Microscopy showed the morphology of the coarse starch granules as uniform in size and lacking protein particles on its smooth surface. Differential Scanning Calorimetry revealed the coarse starch had higher enthalpy changes while Rapid Visco Analysis showed higher peak, trough, and breakdown viscosities for the fine starch. In vitro digestibility featured the fine starch containing lower fast digesting starch contents, but with higher resistant starch content, indicating its resistance to enzymatic hydrolysis. The results could provide theoretical support for application of pea starch in functional foods and the manufacture of emerging starch products.

Bioactive compounds and biological properties of Brazilian stingless bee honey have a strong relationship with the pollen floral origin.

Multivariate data analysis feasibility for the evaluation of Brazilian stingless bee honey (SBH) by pollen spectrum, bioactive compounds content, physicochemical, antioxidant and antimicrobial analysis was investigated. Levels of total and individual phenolics content were analyzed by HPLC-PDA. The antioxidant capacity was performed by 2,2-diphenyl-1-picrylhydrazyl free radical (DPPH), oxygen radical absorption capacity (ORAC) and ferric reducing antioxidant power (FRAP) assays. The total phenolic compounds from the thirty-two SBH was positively correlated with the antioxidant capacity. Bioactive compounds such as p-coumaric acid, quercetin, and hesperetin were identified in all the samples. Brazilian SBH shows more effective antibacterial activity against Gram-negative bacteria (E. coli and S. Typhimurium) compared to Gram-positive ones. Results also revealed that SBH could reach up to 45% higher antioxidant and biological activities than the traditional Apis mellifera honey. Chemometrics shows that chemical and biological properties of SBH have a strong relationship with the pollen botanical origin. Principal component analysis (PCA) grouped the honey into three categories with predominant pollen from Verbenaceae, Asteraceae and Sapindaceae families, confirming that SBH belonging to the same floral origin present similar characteristics.

Factors affecting mushroom Pleurotus spp.

Pleurotus genus is one of most extensively studied white-rot fungi due to its exceptional ligninolytic properties. It is an edible mushroom and it also has several biological effects, as it contains important bioactive molecules. In basidiomycete fungi, lignocellulolytic enzymes are affected by many typical fermentation factors, such as medium composition, ratio of carbon to nitrogen, pH, temperature, air composition, etc. The survival and multiplication of mushrooms is related to a number of factors, which may act separately or have interactive effects among them. Out that understanding challenges in handling Pleurotus species mushroom requires a fundamental understanding of their physical, chemical, biological and enzymatic properties. This review presents a practical checklist of available intrinsic and extrinsic factors, providing useful synthetic information that may help different users. An in-depth understanding of the technical features is needed for an appropriate and efficient production of Pleurotus spp.

Sapucaia nut (Lecythis pisonis Cambess.) flour as a new industrial ingredient: Physicochemical, thermal, and functional properties.

The aim of this work was to investigate the physicochemical, thermal, and functional properties of partially defatted sapucaia nut (Lecythis pisonis Cambess.) flours (PDSF) degreased by subcritical propane (20-60 °C; 20-100 bar) and supercritical CO2 + ethanol (1:1 w/w) as co-solvent (60 °C; 200 bar) in comparison to the PDSF obtained through Soxhlet extraction with petroleum ether. Under the conditions studied herein, compressed propane has a minor effect on the granules' morphology (average particle size between 22 and 32 µm) or in the physicochemical characteristics of the PDSF. It caused a minimum impact on the nutritional profile of the samples; unlike, the thermogravimetric analysis revealed that there is an influence on the thermal stability of the PDSF. Functional characteristics, such as emulsifying (8-20 m2/g), foam (6-12%), and high water (0.35-1.38 g/g flour) and oil (0.72-1.57 g/g flour) absorption capacity, were observed in PDSF. Defatted flours were found to be effective in the production of emulsions with structures that showed micrometric-sized droplets (up to 85% droplet size <15.0 µm) with alleged stability. PDSF is a source of proteins (31-49%) and carbohydrates (17-31%), thus it can be used as an ingredient to produce foodstuff in bakery and confectionery aiming to increase their nutritional value and functional properties.