Comprehensive analysis of integrated processing approaches for chickpeas: enhancing nutritional, functional and bioactive attributes for novel plant-based beverage base

Abstract

The increasing demand for plant-based beverages requires exploring different sources and processing strategies for developing nutritional and functional products. The present dissertation comprises four manuscripts focused on the effect of processing strategies on chickpeas and chickpea ingredients to produce plant-based beverages or powder beverage bases. Processing strategies assessed herein included the combination of extrusion with enzymatic hydrolysis to obtain a chickpea beverage base. This beverage base was further processed by either drying it for convenient handling or fermenting it to develop potential probiotic products. The first manuscript, titled Effect of thermal, nonthermal, and combined treatments on functional and nutritional properties of chickpeas comprises a critical literature review that synthetizes the effects of thermal, non-thermal, and combined processing strategies on chickpea functional and nutritional properties. This provides a wide understanding of the modifications induced and highlights the necessity of carefully selecting processing methods to achieve desired end-product attributes. Further experimental studies are necessary to comprehensively assess the effect of spry drying and fermentation on the novel chickpea hydrolysate and its suitability for beverage formulations. The research presented in the second manuscript, Effect of spray-drying or fermentation on the solubility and carbohydrate profile of chickpea hydrolysates for beverage formulation, demonstrated that spray-drying induced a more amorphous structure with reduced particle sizes, and improved suspension stability compared to freeze-drying, conferring attributes beneficial for plant-based beverages. Meanwhile, lactic acid fermentation prior to freeze-drying promotes higher crystallinity, larger particle sizes, and less stable suspensions in contrast with the freeze-dried beverage base. Solids separation, a previous step included in the processing strategy, made soluble dietary fraction predominant in all cases, contributing to the overall high solubility. Spray-drying with adjuvants and fermentation induced reductions in starch and raffinose family oligosaccharides contents. Processing strategies could also induce different modifications on the antinutrients and phenolic compounds of the beverage, which were evaluated in the third manuscript, Effects of spray-drying and uses of inulin and maltodextrin as adjuvants on phenolics, bioaccessibility, and in vitro glucose consumption modulation in HepG2 cells of extrudate chickpea hydrolysate powderized. Findings indicated differences in the antinutrients concentration, phenolic compounds profile and concentrations, along with the effect in glucose consumption in an insulin resistant model of HepG2 cells related to spray-drying without adjuvants or in addition of inulin and maltodextrin, with spray-drying with inulin showing overall best performance. Furthermore, the effect of extrusion in reducing tannins and trypsin inhibitor activity was also mentioned. A different approach was evaluated in the fourth manuscript, Development of chickpea beverages through enzymatic treatments: from rapid visco analyser to pilot plant production, which focused on a practical pathway for scalable chickpea beverage production. This work demonstrated the potential of Rapid Visco Analyzer as an efficient laboratory-scale tool for optimizing enzymatic hydrolysis aimed at viscosity reduction of starch-containing ingredients like chickpeas, for plant-based beverages. This work demonstrated the direct translatability of lab-scale RVA findings to pilot plant production, achieving consistent physicochemical properties comparable to those observed in previous laboratory trials. This dissertation demonstrated the importance of tailored processing in enhancing the value of chickpeas. It provides valuable information on various processing methods for chickpea-based beverages and powdered beverage bases, which are helpful for the food industry in developing novel, nutritious, and potentially beneficial chickpea-based products for the plant-based beverage market.