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The fermentation process of plant-based yoghurt (PBY)-like products must be followed for consistency by monitoring, e.g., the pH, temperature, and lactic acid concentration. Spectroscopy provides an efficient multivariate in situ quality monitoring method for tracking the process. Therefore, quality monitoring methods for pea- and oat-based yoghurt-like products using Fourier transform infrared (FT-IR) spectroscopy and high-performance liquid chromatography (HPLC) were developed and modeled. Plant-based yoghurt (PBY) was formulated by fermenting pea and oat plant drinks with a commercial starter culture based on Lactobacillus and Streptococcus strains. The main variance during fermentation was explained by spectral carbohydrate and protein bands with a notable shift in protein band peaks for the amide II band at 1548 cm−1 to 1576 cm−1. In addition to the identification of changed spectral bands during fermentation, FT-IR efficiently tracked the variation in oat and pea fermentation using pH as the main indicator. Prediction models with an R2 for the predicted value of pH as a fermentation indicator (R2 = 0.941) with a corresponding root-mean-squared error of prediction (RMSEP) of 0.247 was obtained when compared to the traditional pH method.

The growing interest in fermented plant-based milks and the availability of starter bacterial cultures, as well as equipment (devices that maintain the temperature at the appropriate level for fermentation, dedicated to use at home) have a resulted in many consumers not only producing plant-based milks at home, but also fermenting them. Moreover, the importance of homemade plant-based foods and beverages (including fermented products) significantly increased in recent years. The fermentation of commercial and homemade almond, oat and soy milks to obtain plant-based yogurt alternatives for fresh consumption was compared regarding microorganisms viability, physicochemical characteristics (pH, viscosity, stability), bioactive compounds changes (proteins, free amino acids, total carbohydrates, reducing sugars, polyphenolics and flavonoids) as well as antioxidant activity (DPPH, ABTS, O2− radicals scavenging activities and reducing power). The results showed that both commercial and homemade plant-based milks can be successfully fermented, ensuring high number of Lactic Acid Bacteria, high content of bioactive ingredients and antioxidant activity. Homemade plant-based milks are an attractive alternative to their commercial counterparts, moreover, considering the content of bioactive ingredients (such as polyphenols and flavonoids) and antioxidant activity, homemade almond, oat and soy milks showed a more favorable profile.

In recent years, the different dietary needs of consumers due to their health problems, such as food allergies and lactose intolerance, or lifestyle changes, well-being trends, and increasing awareness about environmental concerns, causes an increment in consumers’ demand to have more plant-based foods in the diet. In this regard, more sustainable alternatives for different food systems come into prominence, and the market size for new plant-based alternatives, especially for dairy products, is ever-increasing. Ice cream is a complex colloidal structure and is defined as a frozen foam that is considered a suitable matrix for plant-based milk substitutes. Although it is hard to obtain a stable colloidal ice cream structure when replacing cow’s milk with plant-based alternatives, the coconut-based, soy-based, and almond-based milk alternatives are regarded as some of the most suitable choices for ice cream production. According to studies, coconut milk’s fat and protein content helps the formation of emulsion and stabilization of the foam system. Also, it is indicated that soy-based ice cream is a good carrier for probiotics, has a better melting resistance, and has comparable sensorial properties with dairy ice cream when used together with milk alternative combinations. However, some technological, microbiological, and sensorial properties of plant-based ice creams were not similar to ice cream made with cow’s milk. Eventually, innovative approaches to producing ice cream with different milk alternatives could be promising and beneficial for the sustainable food industry and should continue to be developed to meet the current needs and interests.

Due to a growing challenge to feed the world’s population and an increased awareness to minimize the impact of our food choices on climate change, a more plant-based diet has gained popularity with a growing number of plant-based products on the market. To stimulate a plant-based diet that also improves long-term health, data are needed to monitor whether these products are healthy alternatives to animal-based foods. Therefore, this study inventoried 916 plant-based meat, fish, and dairy alternatives from eight Dutch supermarkets. The nutritional quality of each product was assessed by (1) the Dutch food-based dietary guidelines and (2) the Nutri-Score. The results show that over 70% of meat, fish, and dairy alternatives have an A/B Nutri-Score (indicating high nutritional quality), but do not comply with the Dutch dietary guidelines. This is mainly due to high salt and low vitamin B12 and iron content (meat and fish alternatives) or low protein and calcium levels (dairy alternatives). In conclusion, the majority of plant-based products are nutritionally not full alternatives of the animal-based equivalents; however, there are still opportunities for reformulation. To aid the consumer in making healthy plant-based food choices, a better alignment between the Nutri-Score and the recommended dietary guidelines is needed.

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.

Cannabis sativa (hemp) is a plant considered to be abundant in bioactive compounds. The increasing production of hemp oil is leaving considerable amounts of hemp press cakes (HPC), which have not been sufficiently managed so far. One of the directions of development of plant-based food is the use of by-products of the agri-food industry in accordance with the idea of zero waste and the circular economy, so the purpose of this study was to determine the possibility of HPC fermentation using yogurt and kefir cultures and to determine the effect of the type of starter on the properties of the products. In the present study, starter cultures of yogurt (YO 122) and kefir (commercial grains) were used for HPC fermentation. Changes in lactic acid bacteria (LAB) and yeast population, pH, acidity, the content of bioactive compounds by spectrophotometric methods (proteins, amino acids, polyphenols, flavonoids, reducing sugars) and antioxidant activity (DDPH, ABTS, FRAP and reducing power) were determined. The results showed that it was possible to develop high-value beverages based on HPC with high fermentation efficiency: survivability of LAB and yeast (>106 CFU/g) and acidification (pH in a range of 4.82–6.36 and 5.34–6.49 for yogurt and kefir culture, respectively). Moreover, the stability of hemp protein, with its variable free amino acid composition, antioxidant potential and presented changes in polyphenolic content, was observed during storage. The presented results show a new way to manage HPC as an oil industry residue by using it as a raw material for the development of a bioactive food product and illustrate the relationship between applied starter culture, the direction of fermentation and changes in the content of bioactive compounds.

Within the present study, the effects of fermentation on the anti-inflammatory and anti-platelet properties of both homemade and commercially purchased bovine dairy and almond, coconut, and rice-based dairy alternatives were evaluated. The extracted total lipids (TL) from homemade and commercially purchased fermented and unfermented bovine, almond, coconut, and rice-based products were further separated into their neutral lipids (NL) and polar lipids (PL) fractions by counter current distribution. The TL, PL, and NL of each sample were assessed in human platelets against the inflammatory and thrombotic mediator, platelet-activating factor (PAF), and the well-established platelet agonist, adenosine 5′ diphosphate (ADP). In all samples, the PL fractions showed significantly stronger inhibitory effects against human platelet aggregation induced by PAF or ADP, in comparison to the TL and NL, with higher specificity against PAF. PL of all fermented products (bovine yogurt and fermented dairy alternatives from almond, rice, and coconut), exhibited the strongest anti-inflammatory and anti-platelet potency, in comparison to PL from their initial pasteurized materials (bovine milk and rice, almond, and coconut-based dairy alternative drinks). PL of the pasteurized rice-based drink and, especially PL from the novel homemade rice-based fermented product (HMFRD), showed the strongest anti-PAF and anti-ADP potency compared to all samples, with anti-PAF activity being most potent overall. The unfermented pasteurized coconut-based drink showed the lowest anti-inflammatory and anti-platelet potency, and the bovine and almond-based fermented products showed an intermediate effect. Further lipidomics with LC-MS analysis of all these PL fractions revealed that fermentation altered their fatty acid content in a way that decreased their degree of saturation and increased the content of unsaturated fatty acids, thus providing a rationale for the stronger anti-inflammatory and anti-platelet potency of the more unsaturated PL fractions of the fermented products. This study has shown that fermentation alters the fatty acid content and the bio-functionality of the PL bioactives in both fermented bovine dairy and plant-based dairy alternatives, and subsequently improved their anti-inflammatory and anti-platelet functional properties.

Plant-based fermented beverages are growing in popularity due to the rise in vegetarianism, health trends and ethical concerns. In this study, camelina (Camelina sativa L.) seed press cake (CPC, 15% and 20% w/w) was fermented using yogurt starter culture. The physicochemical properties of the samples, including pH, total acidity, color, viscosity, texture and rheological properties were investigated. Moreover, the lactic acid bacteria (LAB) viability, bioactive compounds and antioxidant activity were determined. During fermentation and 28-day refrigerated storage, the samples achieved a mean viable bacterial count of at least 1010 CFU/g, which is higher than the recommended bacteria level for traditional dairy yogurt (106 CFU/g). A significant acidification, consumption of reducing sugars, increase in free amino acids and polyphenolics was observed. In addition, CPC-based fermented samples showed good antioxidant potential. Textural and rheological characteristics were similar to dairy yogurt. Moreover, fermentation improved the sensory attributes of CPC, meeting consumers’ acceptance criteria. Thus, the study indicated that fermentation had a marked effect on the physicochemical, microbiological and functional properties of CPC. Therefore, the fermented CPC-based beverage has the potential to be a valid, value-added and novel alternative to dairy-based yogurt.

In recent years, there has been a growing interest from the food industry in new products that are increasingly desired by consumers because of the functional ingredients they contain. This category certainly includes fermented plant-based beverages, which combine the properties of plant substrates with the beneficial effects of fermentation on human health. In our study, two trial variants containing 20% and 30% black cumin (Nigella sativa L.) seed press cake (BCPC) were inoculated with kefir grain cultures and then incubated at 25 °C for 24 h. The resulting beverages were stored under refrigeration (6 °C) for 28 days. During storage, pH, total free amino acids, reducing sugars, changes in the microbial population, viscosity, textural parameters, and color were measured on days 1, 5, 7, 14, 21, and 28. Throughout the storage period, the number of lactic acid bacteria, as well as yeasts, exceeded the recommended minimum level. Numerous changes in product parameters were observed in the tested beverages as a result of fermentation compared to non-fermented products. This study indicates the possibility of using BCPC as a valuable matrix for the production of a functional kefir-like beverage.