Influence of °Brix/Acid, and flow rate of pineapple juice and electric field strength on the performance of continuous ohmic heating system

A lab-scale continuous ohmic heating (COH) system was developed, and its performance was studied for pineapple juice heating as a model sample. The effect of independent parameters [°Brix/Acid (unstandardized, 18, 22, 26) and flow rate (80-120 mL/min) of juice and electric field strength (EFS: 25-45 V/cm)] were analysed for responses viz. come-up-time, heating rate (HR) and system performance coefficient (SPC). The full factorial experimental design was used for this study. The results showed that with an increase in °Brix/Acid, the % acidity and electrical conductivity decreased significantly (p < 0.05); thus, the come-up-time to reach 90 °C increased significantly. The HR was significantly (p < 0.05) influenced by °Brix/Acid and EFS but less so by flow rates at higher EFS. The SPC was more than 0.90 and reduced significantly (p < 0.05) with an increase in °Brix/Acid and flow rate. The HR was modeled using a feed-forward back-propagation artificial neural network (ANN) with the best topology of 3, 5, and 1 neurons in the input (independent), hidden, and output (response) layers, respectively. The model performed efficiently, which is evident from the high R2 (0.998) and low RMSE (1.255). Thus, the COH, with its high efficiency and HR, can effectively be used to process fruit juice.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-024-05961-x.

Valorization of Cashew Apple Waste into a Low-Alcohol, Healthy Drink Using a Co-Culture of Cyberlindnera rhodanensis DK and Lactobacillus pentosus A14-6

This study investigated the potential of microbial fermentative transforming processes in valorizing the cashew apple by-product into a low-alcohol, health-benefiting beverage. We particularly investigated the use of a non-Saccharomyces yeast, Cyberlindnera rhodanensis DK, as the main targeted microbe. At 30 °C without agitation, C. rhodanensis DK caused changes in key parameters during the fermentation of cashew apple juice (CAJ) in terms of varied pH values and initial sugar concentrations. This result indicated that pure CAJ, with pH adjusted to 6 and with the original 6.85% (w/v) total sugar content, was the most feasible condition, as glucose and fructose were mostly consumed at 12 days of fermentation. A co-culture approach with either Saccharomyces cerevisiae TISTR 5088 or Lactobacillus pentosus A14-6 was investigated to improve both physicochemical and fermentation characteristics. Co-fermentation with S. cerevisiae TISTR 5088 resulted in significantly increased ethanol accumulation to 33.61 ± 0.11 g/L, but diminished bioactive compounds, antioxidant activity, and antidiabetic potential. In contrast, co-fermentation with L. pentosus A14-6 demonstrated excellent outcomes, as it significantly increased sugar consumption and finally remained at only 4.95 g/L compared to C. rhodanensis DK alone, produced lower levels of ethanol at only 19.47 ± 0.06 g/L, and higher total titratable acid (TTA), resulting in a final pH of 3.6. In addition, co-fermentation with this lactic acid bacterium significantly enhanced bioactive compounds and antioxidant activity and also retained potential antidiabetic properties. These findings highlight the feasibility of using tailored microbial fermentation strategies to produce low-alcohol beverages with enhanced health-promoting properties from CAJ; however, product-development processes following health food regulations and sensory evaluation are necessary.

Predicting the optimum harvesting dates for different exotic apple varieties grown under North Western Himalayan regions through acoustic and machine vision techniques

Acoustic system and machine vision were used to evaluate the effects of different harvest dates on the quality and sensory attributes of exotic apple varieties of North Western Himalayan. Gala Redlum (V1) was harvested at 110 (H1), 120 (H2) and 130 (H3) Days from Full Bloom (DFFB); Red Velox (V2) and Super Chief (V3) were harvested at 130 (H1), 140 (H2) and 150 (H3) DFFB. Highest acoustic coefficient (21.13) and firmness (20.72 lbs) recorded at first harvest date (H1) decreased significantly (p ≤ 0.05 ) (19.86 to 17.90 lbs) at second harvest (H2) and (17.77 to 16.80 lbs) at third harvest date. Highest starch iodine rating (3.72); anthocyanin content (24.81 mg/100 g); total soluble solids (12.10 %); total sugars (8.75 %) were recorded at H3 in all the varieties. For Gala Redlum (V1) 130 DFFB and for Red Velox (V2) and Super Chief (V3) 150 DFFB were predicted as suitable harvesting dates for table consumption.

Non-Lactic Probiotic Beverage Enriched with Microencapsulated Red Propolis: Microorganism Viability, Physicochemical Characteristics, and Sensory Perception

This work aimed to develop a non-dairy functional beverage fermented with probiotic strains and fortified with Brazilian red propolis (microencapsulated and extracted). The non-dairy matrix consisted of oats (75 g), sunflower seeds (175 g), and almonds (75 g). It was fermented by a starter co-culture composed of Lactiplantibacillus plantarum CCMA 0743 and Debaryomyces hansenii CCMA 176. Scanning electron microscopy analysis was initially performed to verify the integrity of the microcapsules. The viability of the microorganisms after fermentation and storage, chemical composition (high performance liquid chromatography (HPLC) and gas chromatography coupled to mass spectrometry (GC-MS) analyses), rheology, antioxidant activity, and sensory profile of the beverages were determined. After fermentation and storage, the starter cultures were well adapted to the substrate, reducing the pH (6.50 to 4) and cell count above 7.0 log CFU/mL. Lactic acid was the main organic acid produced during fermentation and storage. In addition, 39 volatile compounds were detected by gas chromatography coupled to mass spectrometry (GC-MS), including acids, alcohols, aldehydes, alkanes, alkenes, esters, ethers, phenols, terpenes, and others. The addition of propolis extract increased the antioxidant and phenolic activity and the presence of volatile esters but reduced the beverage’s acceptability. The addition of microencapsulated propolis was more associated with the presence of higher alcohols and had similar acceptance to the control beverage. The combination of a non-dairy substrate, a starter co-culture, and the addition of propolis led to the development of a probiotic beverage with great potential for health benefits.

From food waste to functional component: Cashew apple pomace

Globally, large numbers of people suffer from undernourishment and food insecurity, while a third of food produced is lost or wasted. The widely cultivated cashew nut produces large quantities of waste in early processing. It grows on an edible peduncle called the cashew apple which contains many essential nutrients. An estimated 36.9 million tons of cashew apples are produced annually, but only small amounts are used to make juice. The remainder is considered production waste. This review presents the potential of cashew apple pomace as a food ingredient and examines the effects of incorporation on chemical composition, physical properties and sensory evaluation. Inclusion in optimized amounts into food products is a strategy proven to produce palatable results with high acceptability. Transforming this manufacturing by-product into a functional food component will have economic benefits, improve resource-utilization, promote sustainability and potentially increase the nutritional value of foods.

Development of a new bio-microscope for 3D geometry characterization of fruit single cells

Fruit cells are living irregular three-dimensional (3D) transparent objects which makes them challenging to determine their real 3D size and shape through only two-dimensional (2D) images using the existing biological microscope. This study deals with a newly self-developed biological microscope including a microscope imaging system, a light source system, a stage and a support base for the 3D size characterization of fruit single cells. The main design concept is based on two optical path systems set up at the front (x-axis) and bottom (z-axis) directions of a transparent chamber containing single cells that allow the front view and bottom view of the single cell to be observed. Performance indicators such as mass, size, observation range, objective magnification, total magnification, focal range, focal accuracy, and resolution of the developed biological microscope were estimated. Finally, the 3D geometry size of single tomato cells was measured by the new biological microscope to demonstrate the relative ease at which accurate real 3D geometry information of single fruit cells could be obtained, which echoes its scientific value.

Correlating the morphology of Anacardium occidentale L. fruits from 30 orchards with their physicochemical and nutritional properties

Cashew (Anacardium occidentale L.) is a cross-pollinating plant whose fruit consists of two parts, the nut, and the apple. This study aimed to carry out agro-morphological characteristics of cashew fruits to establish relationships with their physicochemical and nutritional properties. Thirty (30) cashew accessions fruits were sampled in different regions of Burkina Faso. The length, width, thickness, weight, yield, kernel output ratio (KOR), proximate composition, specific minerals, phenolic compounds, and anti-nutritional factors were assessed. Evaluations were made using standard methods. The results showed significant variations in agro-morphological, physicochemical and nutritional traits depending on the accessions and the organ. Also, the ratio of apple mass versus nut one was about 12.24 ± 1.24. Kernels are an important source of proteins, fat, total phenolic compounds, and flavonoids, with average contents of 22.84 ± 1.25 g/100 g, 51.65 ± 2.54 g/100 g, 9.78 ± 2.15 mg GAE/g, and 6.24 ± 12.15 mg QE/g, respectively. As for the apples, they contained substantial quantities of Potassium, Phosphorus, Chlorine, and Magnesium with contents of 611.24 ± 14.5 mg/100 g, 418.24 ± 16.47 mg/100 g, 332.24 ± 10.54 mg/100 g, and 224.95 ± 13.15 mg/100 g, respectively. Statistical analyses showed that mineral and phytate contents were positively correlated to cashew apples while phenolic compounds and tannins were strongly correlated with walnuts. Principal component analyses showed three groups of accessions based on apples and kernels characteristics. These data showed a direct relationship between cashew physicochemical, nutritional potentials, kernels, and apples' agro-morphological characteristics. These data constitute an important basis for the identification of cashew accessions with high nutritional and economic potential.

Cellulase production by Aspergillus niger using urban lignocellulosic waste as substrate: Evaluation of different cultivation strategies

Cellulases are used in various industries, acting efficiently and sustainably in the degradation of cellulose contained in different raw materials and recovering high value products. It is the third largest group of enzymes consumed industrially, as they are required in processes linked to the food, biofuel, textile, cleaning products, among others. However, the main disadvantage in the use of commercial cellulases is the high cost. In this context, the objective of this work was to determine conditions for obtaining more efficient and economical cellulases. For this, the efficiency in obtaining the extracellular cellulases endoglucanase (CMCase) and exoglucanase (FPase) by a fungus Aspergillus niger was investigated using an urban lignocellulosic waste as substrate characterized by tree leaves collected from squares and avenues in urban areas. As urban lignocellulosic waste is an innovative raw material, its chemical composition was determined. This substrate contains 20.36% cellulose and induced the production of cellulases in all fermentation methods, proving to be a promising and sustainable source. The influence of the nutrient medium on CMCase and FPase activities was evaluated for three different sequential fermentation (SF) configurations. Medium 2 provided an increase of up to 100 U/L of CMCase and FPase in relation to medium 1. The interactive effect of pH and moisture content on CMCase e FPase production under SF was studied in a central composite design (CCD). Also, different fermentation methods (solid state, submerged and sequential) were evaluated. The use of SF increased the enzymatic activities of both cellulases by 140% compared to other conventional methods and also stood out in the production of proteins (270.05 μg/mL) and reducing sugars (1.19 mg/mL). The desirability function determined the optimal activities of CMCase and FPase as 413.49 U/L and 230.68 U/L, respectively, obtained from the optimal variables of pH 5.5 and 75% moisture content under SF. The effect of pH and moisture content on the activity of each cellulase was analyzed using the Pareto chart and response surface methodology (RSM). These results revealed favorable strategies for cellulase production, such as the use of urban lignocellulosic waste, SF and ideal operational conditions.

Chironji (Buchanania lanzan) fruit juice extraction using cellulase enzyme: modelling and optimization of process by artificial neural network and response surface methodology

Chironji fruit juice extraction using cellulase enzyme was performed at various concentrations of cellulase, incubation temperature, and time. Artificial neural network (ANN) conjugated with genetic algorithm (GA), and response surface methodology (RSM) were used for attaining the process conditions where the highest juice yield can be achieved. The recommended values of process parameters obtained using ANN-GA method were cellulase concentration of 0.093% (w/w), incubation temperature of 45.7 °C, and incubation time of 116 min. Using RSM method, the recommended values were cellulase concentration of 0.081% (w/w), incubation temperature of 39.6 °C, and incubation time of 99 min. However, the incubation time was found to be the most significant independent process parameter followed by cellulase concentration that affect the juice yield. The juice yield determined experimentally at RSM and ANN-GA recommended conditions was 69.77 ± 0.16% and 70.15 ± 0.12%, respectively. These values indicated that both RSM and ANN-GA methods have comparable accuracies. However, juice extracted using ANN-GA recommended conditions had better physicochemical properties than the juice extracted using RSM recommended conditions.

Physicochemical, nutritional, bioactive compounds and fatty acid profiling of Pumpkin flower (Cucurbita maxima), as a potential functional food

The edible flowers and its several products gaining its importance as functional food. Pumpkin flower mainly consumed in India and Mexico but due to lack of scientific research there is a neophobia among people. The objective of the paper is to analyse the physicochemical, biochemical properties, proximate analysis, antioxidant activities, anthocyanin content and fatty acid profiling. The fresh pumpkin flower was having an average moisture content of 85% (wb) with a dimension of 90 × 51 x 22 mm (l x w x t). The (L, a*, b*) value signifies the bright yellow color having gumminess (26 g) and chewiness (4.70 mJ). In this study the nutritional properties of the pumpkin flower were also determined and significant amount of Sodium (11.5 mg/100 g), Potassium (18.2 mg/100 g), Calcium (17.6 mg/100 g), phenol (17.39 µg/ml), flavonoid (17.13 µg/ml), antioxidant (51.65%DPPH) and anthocyanin (10.3 mg/100 g) was present. Among several fatty acids’ oleic acid (21%), myristic acid (15.99%) and stearic acid (15.19%) was maximum. The presence of several phytonutrients and fatty acids makes pumpkin flower a potential source of functional food in near future.

Graphical abstract

Modeling and optimization of pectinase-assisted low-temperature extraction of cashew apple juice using artificial neural network coupled with genetic algorithm

In this study, pectinase-assisted extraction of cashew apple juice was modeled and optimized using a multi-layer artificial neural network (ANN) coupled with genetic algorithm (GA). The effect of incubation time, incubation temperature, and enzyme concentration on different responses such as yield, turbidity, ascorbic acid content, polyphenol content, total soluble solids, and pH was also determined. The developed ANN has minimum mean squared error values of 0.83, 40.92, 29.01, and 8.95 and maximum R values of 0.9999, 0.9972, 0.9995, and 0.9996 for training, testing, validation, and all data sets, respectively, which shows good agreement between the actual and predicted values. The optimum extraction parameters obtained using the developed ANN-GA were as follows: an incubation time of 64 min, incubation temperature of 32 °C, and enzyme concentration of 0.078%. The measured value of responses at the optimized process conditions were in accordance with the predicted values obtained using the developed ANN model.