Mango peel flour and potato peel flour as bioactive ingredients in the formulation of functional yogurt

Reutilization of Fruit Waste as Potential Prebiotic for Probiotic or Food-grade Microorganisms in Food Applications: A Review

Food waste has been a global issue with 2.5 billion tons generated globally in 2021. Approximately 46% of the food waste is contributed by fruit and vegetable waste. Due to improper waste handling, these fruit by-products have a negative impact on the environment through soil and water pollution, the greenhouse effect, global warming, and eutrophication. However, research has shown the potential to reuse fruit waste in various applications for sustainability owing to their high source of valuable components and potential health benefits. In recent years, researchers have also explored the potential of reutilizing fruit waste as a prebiotic. Hence, literatures from the past 10 years has been critically analyzed and presented in this review. This review focused on the potential of fruit waste as a prebiotic for probiotic and gastrointestinal microorganisms and its food applications. The nutritional composition and bioactive compounds of the fruit wastes had been introduced to reflect their potential as prebiotics. Moreover, the increase in bioactive compounds and bioactivities in probiotics with the presence of fruit wastes has been reviewed. The impact of fruit by-products on the growth of the probiotic and its survivability in food matrices as compared to established prebiotic and the absence of prebiotics have also been extensively discussed in this review. This review also highlighted some of the factors that might contribute to the negative effect of fruit waste on probiotics. The safety concerns and future prospects of reutilizing fruit wastes for food applications have been emphasized. The review article is beneficial for researchers exploring fruit wastes as prebiotics and industrialists who are interested in incorporating fruit wastes as an added-value ingredient for food applications.

Physicochemical characterization of pectin and mango peel (Mangifera indica L.) from Mexican cultivars

In Mexico, about 40 % of the mango harvest is lost due to marketing problems. Moreover, the mango industry generates peel and seed waste that ranges from 35 to 60 % of the total weight of processed fruits. This unexploited mango biomass represents a potential resource for producing value-added by-products. A market alternative is exploiting the mango peel as a source of biofunctional compounds, such as pectin. This hydrocolloid has applications in the pharmaceutical, cosmetic, and food industries. This study quantified the peel components of the Ataulfo, Panameño, Manila, and Haden cultivars. The mango peel showed a considerable input of dietary fiber (37-45 % DM), minerals (1018-2156 mg/100 g DM), phenols (2123-4851 mg gallic acid equivalent/100 g DM), flavonoids (0.74-2.7 mg quercetin equivalent/g DM) and antioxidant capacity (375-937 μM Trolox equivalent/g DM). The four cultivars presented high methoxyl pectins (66-71 %). The molecular weight of the pectins analyzed was from 957 to 4859 kDa. The Panameño cultivar showed the highest amount of pectin and viscosity concerning the peel of the other cultivars and a higher content of glucomannans (≈28.21 %). The pectin of the Haden cultivar was the only one with arabinoxylans since xylose was not detected in the pectin of the other cultivars. The chemical characteristics of the studied mango peels are promising for their industrialization.

Sensory, textural, physico-chemical and enzymatic characterization of melted cheese with added potato and carrot peels

Food waste is one of the biggest societal problems in the globe due to its detrimental consequences on the environment. According to estimates from the Food and Agriculture Organization, this comes to about 1.3 billion tonnes per year. The current study aims to produce sustainable food products with high nutritional value by incorporating food waste. For the extraction of economically relevant products such as dietary fibers, biopolymers, natural antioxidants, and food additives, potato and carrot peel represent an inexpensive, valuable, and conveniently available resource. Cheese is a functional dairy product that people eat for its high nutritional content, which aids in the treatment of conditions including diabetes, obesity, hypertension, and digestive problems in addition to giving them energy. Thus a control sample and 10 samples of melted cheese with various amounts of potato and carrot peelings were prepared. To explore the nutritional value of potato and carrot peels in melted cheese, an analysis was conducted on the fluctuation of physicochemical (acidity, pH, dry matter, water activity, and salt content) and enzymatic (L-lactic acid, lactose, D-glucose, and D-galactose) parameters. Consumer acceptability of the products was assessed by textural and sensory analysis. During the whole storage period, the samples of melted cheese with potato and carrot peels recorded higher values than the control sample, the results obtained for them being better. Samples with added potato or carrot wastes were more stable over time, as compared to control samples.

Experimental Investigation and Modeling for the Influence of Adding Date Press Cake on Drinkable Yogurt Quality

The extraction of date syrup produces a large quantity of by-product known as date press cake (DPC). This study aimed to utilize valuable ingredients of the DPC by adding 0 (Control), 2, 4, and 6% (g/100 g) of its powder to drinkable yogurt before fermentation. The physicochemical properties, texture profile, and sensory evaluation of the treated DPC-based drinkable yogurt (DPC drinkable yogurt) were measured after fermentation and 5, 10, and 15 days of storage at 4 °C. The modeling of the most critical quality attributes, i.e., pH, acidity, syneresis, water holding capacity (WHC), viscosity, and color difference (ΔE), was conducted to predict their values based on the DPC percentage and storage period. The DPC drinkable yogurt’s total solids, protein, and fat ranged between 11.19–11.83, 3.10–3.42, and 2.26–2.34%, respectively. Adding 2–6% DPC slightly increased the pH of DPC drinkable yogurt and decreased its acidity (p > 0.05) during storage. Increasing the DPC percent in DPC drinkable yogurt decreased the syneresis value, and WHC increased during storage. The color parameters and viscosity of DPC drinkable yogurt recorded the highest value at the end of the storage period for all treatments and increased steadily with the increase in DPC. The evaluation of the prediction models indicated that the predicted values were close to the actual experimental values for pH (R2 = 0.779), acidity (R2 = 0.973), syneresis (R2 = 0.961), WHC (R2 = 0.989), viscosity (R2 = 0.99), L* (R2 = 0.919), a* (R2 = 0.995), b* (R2 = 0.922), and ΔE (R2 = 0.921). The textural analysis indicated that increasing the concentration of DPC in the DPC drinkable yogurt increased hardness (g), springiness, cohesiveness, and gumminess and decreased adhesiveness and resilience during cold storage. The evaluation of sensory acceptance during the cold storage of the DPC drinkable yogurt was conducted by 30 expert panelists. Each panelist received four cups of 10 mL drinkable yogurt treatments at 5–10 °C. The evaluation results indicated that adding 2% of DPC was closest in overall sensory acceptability to the control sample (p < 0.05). This study revealed the potential use of DPC in drinkable yogurt as a natural, functional, and low-cost ingredient to improve the fiber content, physicochemical properties, and overall acceptability. Therefore, the fermented DPC-based yogurt drink has the potency to be a practical, value-added, and novel alternative to dairy-based yogurt.