Like other plant-based (PB) product categories, PB milk alternatives (PBMA) are in ascendency as part of the green consumer transition and a greater focus on personal health. However, consumption remains far below that for cow\'s milk, and among multiple barriers to uptake, inferior sensory properties is one problem, nutritional inadequacies another. While exceptions exist in both instances, a general need for improved products remains. The present research is situated in this nexus, and its primary aim was to contribute new consumer-centric insight regarding the sensory drivers of liking/disliking in the PBMA category. This was achieved through a central location study with adult New Zealanders (n = 143, not regular PBMA consumers) who tasted 18 different PBMA samples spanning a broad range of PB ingredients (soy, oat, coconut, almond, rice, cashew, peanut, macadamia, lentil, hemp, sesame) in different product types (single PB source, blends, barista style) with varying nutritional profiles. The most liked sample (6.5/9), which was made from soy, had the nutritional profile that most approximated cow\'s milk (3 g/100 mL protein), as well as a milky appearance and taste. Its mouthfeel was smooth, and this sensory characteristic was also paramount for barista-style PBMAs being well-liked (>5.9/9) regardless of their constituent PB ingredient (oat, almond, coconut). Opportunities for product innovation within this type of PBMA was identified including for using barista-style beyond hot beverages, as these samples received positive liking scores on average. The same applied to blends as multiple-source PBMAs can facilitate improved nutritional composition, and significant scope seemed to exist to identify more liked vs less liked PB ingredient combinations (e.g., almond/rice vs coconut/sesame). By identifying, through penalty/lift analysis that positive sensory drivers of PBMA liking span all sensory modalities (appearance, taste, flavour, texture and mouthfeel), it becomes easier to appreciate that products in this category are complex and challenging to optimise. A second minor research aim was focused on the modulating influence of PBMA consumption frequency on product liking and the sensory drivers of liking. The key result was a positive association between liking and higher consumption frequency, and greater appreciation of sweet, coconut, nutty and cereal/oaty characteristics of PBMAs.

Rice beverages are commonly fortified with minerals to improve their nutritional value. However, the effect of fortification on mineral bioaccessibility is poorly understood. Thus, the effects of fortification of a rice beverage on mineral concentration and bioaccessibility using calcium carbonate (CaCO3), tricalcium phosphate (Ca3(PO4)2), sodium iron EDTA (NaFeEDTA) and ferric pyrophosphate (Fe4(P2O7)3) individually and in combination were studied. Recovery of the added minerals in the rice beverage ranged from 71.4 % to 92.0 % and 61.0 % to 93.3 % for Ca and Fe, respectively. Mineral bioacessibility was shown to be higher for CaCO3(≤39.0 %) compared to Ca3(PO4)2 (≤14.4 %) and for NaFeEDTA (≤50.7 %) compared to Fe4(P2O7)3 (≤3.9 %). No interaction of the different Ca sources was identified; the addition of iron sources did not have a significant effect on Ca bioaccessibility. The addition of NaFeEDTA to the rice beverage was found to be better than the addition of iron pyrophosphate and the simultaneous addition of this iron sources did not result in an additive effect on Fe bioaccessibility. These results may be used to develop plant-based beverages with an improved mineral bioaccessibility.

BACKGROUND: Plant-based milk alternatives are more popular than ever, and chickpea-based milks are among the most commercially relevant products. Unfortunately, limited nutritional value because of low levels of the essential amino acid L-lysine, low digestibility and unpleasant taste are challenges that must be addressed to improve product quality and meet consumer expectations.
RESULTS: Using in-silico screening and food safety classifications, 31 strains were selected as potential L-lysine producers from approximately 2,500 potential candidates. Beneficially, 30% of the isolates significantly accumulated amino acids (up to 1.4 mM) during chickpea milk fermentation, increasing the natural level by up to 43%. The best-performing strains, B. amyloliquefaciens NCC 156 and L. paracasei subsp. paracasei NCC 2511, were tested further. De novo lysine biosynthesis was demonstrated in both strains by 13C metabolic pathway analysis. Spiking small amounts of citrate into the fermentation significantly activated L-lysine biosynthesis in NCC 156 and stimulated growth. Both microbes revealed additional benefits in eliminating indigestible sugars such as stachyose and raffinose and converting off-flavour aldehydes into the corresponding alcohols and acids with fruity and sweet notes.
CONCLUSIONS: B. amyloliquefaciens NCC 156 and L. paracasei subsp. paracasei NCC 2511 emerged as multi-benefit microbes for chickpea milk fermentation with strong potential for industrial processing of the plant material. Given the high number of L-lysine-producing isolates identified in silico, this concept appears promising to support strain selection for food fermentation.