New Alternatives to Milk From Pulses: Chickpea and Lupin Beverages With Improved Digestibility and Potential Bioactivities for Human Health

Abstract

There is a strong demand for plant-based milk substitutes, often low in protein content (<1.5% w/v). Protein-rich pulse seeds and the right processing technologies make it possible to make relevant choices. The major objective of this study was to assess the impact of processing on the nutritional characteristics of beverages with a high impact on health, in particular on digestibility and specific bioactivities. The results suggest that pulse beverages are as high in protein content (3.24% w/v for chickpea and 4.05% w/v for lupin) as cow's milk. The anti-nutrient level characteristics of pulses have been considerably reduced by strategic processing. However, when present in small quantities, some of these anti-nutritional factors may have health benefits. Controlling processing conditions play a crucial role in this fine balance as a tool to take advantage of their health benefits. There is evidence of protein hydrolysis by in vitro digestion and limited bioaccessibility of minerals. In addition to being highly digestible, lupin and chickpea beverages have anti-inflammatory and anti-carcinogenic potential evaluated through the inhibition of metalloproteinase MMP-9.

Keywords: bioaccessibility; bioactivity; chickpea; digestibility; lupin; non-dairy beverages; pulses.

FIGURE 1

Hemagglutination activity (A,B): serial dilutions (1:2) of the beverage and digesta extracts (50 or 100 μg of protein; L, lupin; dL, lupin digesta; Cp, chickpea; dCp, chickpea digesta) and negative (C–; saline) and positive (C+; 35 μg Con-A) controls. (C) Hemagglutination activity H.U. (μg) of assayed samples.

FIGURE 2

Protein hydrolysis after in vitro digestion. Silver-stained SDS-PAGE gel (17.5% w/v polyacrylamide) ran under reducing conditions. Expected molecular weights are indicated for the molecular weight standards. The quantity of protein loaded in each lane is 15 μg for chickpea and lupin beverages, and 7 μg for both digesta and enzyme-blank control. M, protein molecular weight markers; C, chickpea beverage polypeptides; dC, chickpea whole digesta polypeptides; L, lupin beverage polypeptides; dL, lupin whole digesta polypeptides; B, enzyme-blank control.

FIGURE 3

The effect of the beverages and digesta extracts (L, lupin; dL, lupin digesta; C, chickpea; dC, chickpea digesta) on MMP-9 gelatinolytic activity was measured by the DQ-gelatin assay. MMP-9 activity is expressed as relative fluorescence as a % of control and corresponds to the means of at least three replicate assays (n = 3) ± SD. *p < 0.05.